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  • 1.
    Dahlquist, Erik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Kyprianidis, Konstantinos
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Comparison of Gas Quality from Black Liquor and Wood Pellet Gasification Using Modelica Simulation and Pilot Plant Results2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, p. 992-998Article in journal (Refereed)
    Abstract [en]

    There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and methanol etc. To perform system analysis of such integration, it is important to gain knowledge of relevant input data on expected synthesis gas composition by gasifying different types of feed stock. In this paper, the synthesis gas quality from wood pellets gasification (WPG) has been compared with black liquor gasification (BLG) through modeling and experimental results at pilot scale. In addition, the study develops regression models like Partial Least Squares (PLS) made from the experimental data. The regression models are then combined with dynamic models developed in Modelica for the investigation of dynamic energy and material balances for integrated plants. The data presented in this study could be used as input to relevant analysis using e.g. ASPEN plus and similar system analysis tools. 

  • 2.
    Dahlquist, Erik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Royal Institute of Technology (KTH), Sweden.
    Kyprianidis, Konstantinos
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Hartwell, Philip
    BioRegional MiniMills Ltd, UK.
    Experimental and numerical investigation of pellet and black liquor gasification for polygeneration plant2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 204, p. 1066-1064Article in journal (Refereed)
    Abstract [en]

    It is vital to perform system analysis on integrated biomass gasification in chemical recovery systems in pulp and paper and heat and power plants for polygeneration applications. The proposed integration complements existing pulp and paper and heat and power production systems with production of chemicals such as methane and hydrogen. The potential to introduce gasification-based combined cycles comprising gas turbines and steam turbines to utilize black liquors and wood pellets also merits investigation. To perform such analysis, it is important to first build knowledge on expected synthesis gas composition by gasifying at smaller scale different types of feed stock. In the present paper, the synthesis gas quality from wood pellets gasification has been compared with black liquor gasification by means of numerical simulation as well as through pilot-scale experimental investigations. The experimental results have been correlated into partial least squares models to predict the composition of the synthesis gas produced under different operating conditions. The gas quality prediction models are combined with physical models using a generic open-source modelling language for investigating the dynamic performance of large-scale integrated polygeneration plants. The analysis is further complemented by considering potential gas separation using modern membrane technology for upgrading the synthesis gas with respect to hydrogen content. The experimental data and statistical models presented in this study form an important literature source for future use by the gasification and polygeneration research community on further integrated system analysis.

  • 3.
    Dahlquist, Erik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Kyprianidis, Konstantinos
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Hartwell, Philip
    BioRegional MiniMills Ltd., United Kingdom.
    Modeling of Black Liquor Gasification2016Conference paper (Refereed)
  • 4.
    Dahlquist, Erik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Kyprianidis, Konstantinos
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Hartwell, Philip
    BioRegional MiniMills Ltd., United Kingdom.
    Modeling of Wood Gasification in an Atmospheric CFB Plant2016Conference paper (Refereed)
  • 5.
    Danish, M.
    et al.
    East China University of Science and Technology, Shanghai, China .
    Gu, X.
    East China University of Science and Technology, Shanghai, China .
    Lu, S.
    East China University of Science and Technology, Shanghai, China .
    Ahmad, A.
    Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Farooq, U.
    East China University of Science and Technology, Shanghai, China .
    Zhang, X.
    East China University of Science and Technology, Shanghai, China .
    Fu, X.
    East China University of Science and Technology, Shanghai, China .
    Miao, Z.
    East China University of Science and Technology, Shanghai, China .
    Xue, Y.
    East China University of Science and Technology, Shanghai, China .
    Efficient transformation of trichloroethylene activated through sodium percarbonate using heterogeneous zeolite supported nano zero valent iron-copper bimetallic composite2017In: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 308, p. 396-407Article in journal (Refereed)
    Abstract [en]

    Zeolite supported nano zero valent iron copper bimetallic composite (Z-nZVFe-Cu) was synthesized using an ion exchange method. The morphology and physico-chemical properties of the Z-nZVFe-Cu composite were determined using transmission electron microscopy (TEM), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET), energy dispersive X-ray spectra (EDS), Fourier transform infrared spectroscopy (FTIR) and X-ray diffractometer (XRD). The results showed that iron and copper nano particles were well dispersed on the zeolite sheet. The degradation efficiency of trichloroethylene (TCE) achieved was more than 95% using Z-nZVFe-Cu as a heterogeneous Fenton like catalyst. An efficient removal of total organic carbon (TOC) was promoted as compared to zeolite supported iron nano composite (Z-nZVFe) and unsupported nano iron (nZVFe). Electron spin resonance (ESR) detection confirmed the intensity of hydroxyl radicals (OH[rad]) in the system. While benzoic acid (BA), a probe indicator for the quantification of OH[rad], demonstrated the higher intensity of hydroxyl radicals in Z-nZVFe-Cu as compared to Z-nZVFe and nZVFe. The less iron and copper leaching of from Z-nZVFe-Cu presented its higher stability and better catalytic activity, displaying its potential long term applications for TCE degradation in groundwater. 

  • 6.
    Danish, M.
    et al.
    East China University of Science and Technology, Shanghai, China .
    Gu, X.
    East China University of Science and Technology, Shanghai, China .
    Lu, S.
    East China University of Science and Technology, Shanghai, China .
    Zhang, X.
    East China University of Science and Technology, Shanghai, China .
    Fu, X.
    East China University of Science and Technology, Shanghai, China .
    Xue, Y.
    East China University of Science and Technology, Shanghai, China .
    Miao, Z.
    East China University of Science and Technology, Shanghai, China .
    Ahmad, A.
    Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Qureshi, A. S.
    University of Sindh, Jamshoro, Pakistan.
    The Effect of Chelating Agents on Enhancement of 1,1,1-Trichloroethane and Trichloroethylene Degradation by Z-nZVI-Catalyzed Percarbonate Process2016In: Water, Air and Soil Pollution, ISSN 0049-6979, E-ISSN 1573-2932, Vol. 227, no 9, article id 301Article in journal (Refereed)
    Abstract [en]

    This study primarily focused on the performance of 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethylene (TCE) degradation involving redox reactions in zeolite-supported nanozerovalent iron composite (Z-nZVI)-catalyzed sodium percarbonate (SPC) system in aqueous solution with five different chelating agents (CAs) including oxalic acid (OA), citric acid monohydrate (CAM), glutamic acid (GA), ethylenediaminetetraacetic acid (EDTA), and L-ascorbic acid (ASC). The experimental results showed that the addition of OA achieved almost 100 % degradation of 1,1,1-TCA and TCE. The addition of CAM and GA also significantly increased the contaminant degradation, while excessive addition of them inhibited the degradation. In contrast, EDTA and ASC showed negative impacts on 1,1,1-TCA and TCE degradation, which might be due to the strong reactivity with iron and OH● scavenging characteristics. The efficiency with CA addition on 1,1,1-TCA and TCE degradation decreased in the order of OA > CAM > GA > no CAs > EDTA > ASC. The extensive investigations using probe compound tests and scavenger tests revealed that both contaminants degraded primarily by OH● and O2 –● in chelated Z-nZVI-catalyzed SPC system. The significant improvement in 1,1,1-TCA and TCE degradation efficiency was accredited due to the (i) increase in concentration of Fe2+ and (ii) continuous generation of OH● radicals and maintenance of its quantity, ensuring more stability in the aqueous solution. Finally, the complete mineralization of 1,1,1-TCA and TCE in the OA-chelated, Z-nZVI-catalyzed SPC system was confirmed without any chlorinated intermediate by-products detected, demonstrating a great potential of this technique in the application of groundwater remediation.

  • 7.
    Danish, M
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Xu, Minhui
    East China University of Science and Technology, Shanghai, China.
    Xiang, Zhang
    East China University of Science and Technology, Shanghai, China.
    Fu, Xiaori
    East China University of Science and Technology, Shanghai, China.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Miao, Zhouwei
    East China University of Science and Technology, Shanghai, China.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Nasir, Muhammad
    IRCBM, COMSATS Institute of Information Technology, Lahore, Pakistan.
    Role of reactive oxygen species and effect of solution matrix in trichloroethylene degradation from aqueous solution by zeolite-supported nano iron as percarbonate activator2016In: Research on chemical intermediates (Print), ISSN 0922-6168, E-ISSN 1568-5675, Vol. 42, no 9, p. 6959-6973Article in journal (Refereed)
    Abstract [en]

    The role of reactive oxygen species (ROSs) and effect of solution matrix have been investigated for the degradation of trichloroethylene (TCE). Zeolite-supported nano iron (Z-nZVI) was synthesized as an activator to catalyze sodium percarbonate (SPC) with or without hydroxylamine, i.e. as reducing agent (RA). The probe tests confirmed the generation of OH·and O2−· in the Z-nZVI activated SPC system in absence of the RA, while the presence of RA significantly increased the generation of OH· and O2−· radicals. Scavenger tests demonstrated that OH· was the main ROS responsible for TCE degradation, whereas O2−· also participated in TCE degradation. From the solution matrix perspective, the experimental results confirmed significant scavenging effects of Cl− (1.0, 10.0, and 100 mmol L−1) and HCO3− (1.0 and 10.0 mmol L−1), whereas the scavenging effects were fairly impeded at 100 mmol L−1concentration of HCO3−. On the other hand, a considerable decline in scavenging effect was observed in the presence of RA in tested Cl− and HCO3− concentration ranges. In addition, negligible scavenging effects of NO3− and SO42− anions were found in all tested concentrations. The effect of initial solution pH on catalytic activity indicated a significant increase in the TCE degradation in the presence of RA even at higher pH value of 9. The results indicated that the Z-nZVI activated SPC system in presence of RA can effectively degrade chlorinated organic solvents, but it is important to consider the intensive existence of anions in groundwater.

  • 8.
    Danish, Muhammad
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Farooq, Usman
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Qamar Zaman, Waqas
    East China University of Science and Technology, Shanghai, China.
    Fu, Xiaori
    East China University of Science and Technology, Shanghai, China.
    Miao, Zhouwei
    East China University of Science and Technology, Shanghai, China.
    Brusseau, Mark L.
    The University of Arizona, US.
    Ahmad, Ayyaz
    University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    An efficient catalytic degradation of trichloroethene in a percarbonate system catalyzed by ultra-fine heterogeneous zeolite supported zero valent iron-nickel bimetallic composite2017In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 531, p. 177-186Article in journal (Refereed)
    Abstract [en]

    Zeolite supported nano iron-nickel bimetallic composite (Z-nZVI-Ni) was prepared using a liquid-phase reduction process. The corresponding surface morphologies and physico-chemical properties of the Z-nZVI-Ni composite were determined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy dispersive X-ray spectra (EDS), Brunauer Emmett Teller (BET) adsorption, wide angle X-ray diffractometry (WA-XRD), and Fourier transform infrared spectroscopy (FTIR). The results indicated high dispersion of iron and nickel nano particles on the zeolite sheet with an enhanced surface area. Complete destruction of trichloroethene (TCE) and efficient removal of total organic carbon (TOC) were observed by using Z-nZVI-Ni as a heterogeneous catalyst for a Fenton-like oxidation process employing sodium percarbonate (SPC) as an oxidant. The electron spin resonance (ESR) of Z-nZVI-Ni verified the generation and intensity of hydroxyl radicals (OH). The quantification of OHelucidated by using p-chlorobenzoic acid, a probe indicator, confirmed the higher intensity of OH. The transformation products were identified using GC–MS. The slow iron and nickel leaching offered higher stability and better catalytic activity of Z-nZVI-Ni, demonstrating its prospective long term applications in groundwater for TCE degradation.

  • 9.
    Danish, Muhammad
    et al.
    East China University of Science and Technology, Shanghai, China.
    Gu, Xiaogang
    East China University of Science and Technology, Shanghai, China.
    Lu, Shuguang
    East China University of Science and Technology, Shanghai, China.
    Farooq, Usman
    East China University of Science and Technology, Shanghai, China.
    Ahmad, Ayyaz
    University of Engineering and Technology, Multan, Pakistan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Xue, Yunfei
    East China University of Science and Technology, Shanghai, China.
    Zhang, Xiang
    East China University of Science and Technology, Shanghai, China.
    Effect of solution matrix and pH in Z-nZVI-catalyzed percarbonate system on the generation of reactive oxygen species and degradation of 1, 1, 1-trichloroethane2017In: Water Science and Technology: Water Supply, ISSN 1606-9749, E-ISSN 1607-0798, Vol. 17, no 6, p. 1568-1578Article in journal (Refereed)
    Abstract [en]

    This study primarily focuses on evaluating the effects of solution matrix and pH for the generation of reactive oxygen species (ROSs) in Z-nZVI-catalyzed sodium percarbonate (SPC) system to degrade 1,1,1-trichloroethane (1,1,1-TCA) in the absence and presence of reducing agent (RA) i.e. hydroxylamine. 1,1,1-TCA degradation was 49.5% and 95% in the absence and presence of RA. Probe tests confirmed the generation of major hydroxyl radicals (OH•) and minor superoxide species (O2–•), and scavenger tests verified the key role of OH• and less of O2–• radicals. 1,1,1-TCA degradation decreased significantly in the presence of Cl− and HCO3–, while NO3– and SO42– have negligible effects in absence of RA. Addition of RA significantly enhanced 1,1,1-TCA degradation by generating more OH• and O2–• radicals in presence of anions. 1,1,1-TCA degradation increased in acidic range (1–5) while, an inhibitive trend from neutral to basic (7–9) was observed. On the contrary, a significant increase in 1,1,1-TCA degradation was observed with addition of RA in all pH values (1–9). In conclusion, the anions and pH significantly influenced the generation and intensity of ROSs and 1,1,1-TCA was effectively degraded in Z-nZVI-catalyzed SPC system in the presence of RA.

  • 10.
    Danish, Muhammad
    et al.
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Gu, Xiaogang
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Lu, Shuguang
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China..
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Degradation of chlorinated organic solvents in aqueous percarbonate system using zeolite supported nano zero valent iron (Z-nZVI) composite2016In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 23, no 13, p. 13298-13307Article in journal (Refereed)
    Abstract [en]

    Chlorinated organic solvents (COSs) are extensively detected in contaminated soil and groundwater that pose long-term threats to human life and environment. In order to degrade COSs effectively, a novel catalytic composite of natural zeolite-supported nano zero valent iron (Z-nZVI) was synthesized in this study. The performance of Z-nZVI-catalyzed sodium percarbonate (SPC) in a heterogeneous Fenton-like system was investigated for the degradation of COSs such as 1,1,1-trichloroethane (1,1,1-TCA) and trichloroethylene (TCE). The surface characteristics and morphology of the Z-nZVI composite were tested using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Total pore volume, specific surface area, and pore size of the natural zeolite and the Z-nZVI composite were measured using Brunauer-Emmett-Teller (BET) method. SEM and TEM analysis showed significant elimination of aggregation and well dispersion of iron nano particles on the framework of natural zeolite. The BET N-2 measurement analysis indicated that the surface area of the Z-nZVI composite was 72.3 m(2)/g, much larger than that of the natural zeolite (0.61 m(2)/g). For the contaminant analysis, the samples were extracted with n-hexane and analyzed through gas chromatograph. The degradation of 1,1,1-TCA and TCE in the Z-nZVI-catalyzed percarbonate system were 48 and 39 % respectively, while strong augmentation was observed up to 83 and 99 %, respectively, by adding the reducing agent (RA), hydroxyl amine (NH2OH center dot HCl). Probe tests validated the presence of OH center dot and O-2(center dot-) which were responsible for 1,1,1-TCA and TCE degradation, whereas both free radicals were strengthened with the addition of RA. In conclusion, the Z-nZVI/SPC oxidation with reducing agent shows potential technique for degradation of groundwater contaminated by 1,1,1-TCA and TCE.

  • 11.
    Danish, Muhammad
    et al.
    E China Univ Sci & Technol, Peoples R China.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Farooq, Usman
    Gujarat Univ, Gujrat, Pakistan.
    Naqvi, Salman
    Univ Teknol PETRONAS, Univ Teknol PETRONAS, Malaysia.
    Characterization of South Asian agricultural residues for potential utilization in future 'energy mix'2015In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, p. 2974-2980Article in journal (Refereed)
    Abstract [en]

    This paper characterizes various locally available agricultural residues in South Asian region to evaluate their potential as feedstock for renewable energy production and contributing toward solving energy crisis and environmental issues. The thermo-chemical characterization has been performed in order to determine if the residues have potential to be used in biomass conversion technologies producing combined heat and power. The characterization methods for comparing different agricultural residues include proximate and ultimate analysis, heating value, ash content, thermo gravimetric analysis (TGA) and structural composition analysis (SCA). Widely available agricultural wastes in South Asian region were selected for the characterization i.e. bagasse, almond shell, corn cob, cotton stalks, wheat straw, sawdust, corn leaf, rice husk, rice straw, and corn straw. The analysis showed that the corn cob had the highest moisture content that will result in low energy efficiency of the thermal conversion technology due to energy requirement for drying. Whereas almond shell had the lowest moisture content. Ash and volatile contents were found to be highest in rice straw and almond shell respectively. The thermo gravimetric analysis showed that most of the agricultural residues can be easily decomposed and represent potential feedstock for biomass flexible combined heat and power systems through pyrolysis or gasification. (C) 2015 Published by Elsevier Ltd.

  • 12.
    Farooq, U.
    et al.
    East China University of Science and Technology, Shanghai, China.
    Danish, M.
    East China University of Science and Technology, Shanghai, China.
    Lu, S.
    East China University of Science and Technology, Shanghai, China.
    Brusseau, M. L.
    The University of Arizona,Tucson, AZ, United States.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Fu, X.
    East China University of Science and Technology, Shanghai, China.
    Zhang, X.
    East China University of Science and Technology, Shanghai, China.
    Sui, Q.
    East China University of Science and Technology, Shanghai, China.
    Qiu, Z.
    East China University of Science and Technology, Shanghai, China.
    Efficient transformation in characteristics of cations supported-reduced graphene oxide nanocomposites for the destruction of trichloroethane2017In: Applied Catalysis A: General, ISSN 0926-860X, E-ISSN 1873-3875, Vol. 544, p. 10-20Article in journal (Refereed)
    Abstract [en]

    Experiments were conducted to investigate the use of graphene-oxide supported metallic nanocomposites for improving the degradation of trichloroethane (TCA) by sodium percarbonate (SPC). Two methods of production, chemical reduction (CR) and solvo-thermal (ST), were tested for preparation of single (Fe) and binary (Fe-Cu) nanocomposites supported by reduced graphene oxide (rGO). A variety of analytical techniques including N2 adsorption Brunauer-Emmett-Teller (BET), x-ray diffraction (XRD), fourier-transfrom infrared spectroscopy (FTIR), and transmisison electron microscopy (TEM) were applied to characterize the physicochemical and microstructural properties of the synthesized nanocomposites. The characterization indicated that the CR method produced nanocomposites that comprised only mesoporous structure. Conversely, both micro and mesoporous structures were present for samples produced with the ST method. The synthesized single and bimetallic composites produced from the ST method showed higher surface areas, i.e. 93.6 m2/g and 119.2 m2/g as compared to the ones synthesized via the CR method, i.e. 13.8 m2/g and 38.0 m2/g respectively. The results of FTIR and XRD analyses confirmed that the ST method produced highly crystalline nanocomposites. SEM and TEM analysis validated that metallic particles with definite morphology well distributed on the surface of rGO. X-ray photoelectron spectroscopy (XPS) analysis confirmed the homogeneity nanocomposites and occurrence of variation in copper oxidation states during degradation process. EDS mapping validate the homogeneous distribution of Cu and Fe at reduced graphene oxide surface. The Fe-Cu/rGO (ST) activated SPC system effectively degraded TCA (92%) in 2.5 h at low nanocomposite dose compared to the Fe-Cu/rGO (CR) and only Fe, for which the maximum degradation efficiencies achieved were 81% and 34%. In conclusion, excellent catalytic characteristics were observed for the ST-synthesized single and bimetallic (Fe/rGO, Fe-Cu/rGO) catalysts. These catalysts were successful in improving the degradation of TCA via activated SPC. 

  • 13.
    Farooq, U.
    et al.
    East China University of Science and Technology, Shanghai, China.
    Danish, M.
    University of Engineering and Technology Lahore, Faisalabad Campus, Pakistan.
    Lu, S.
    East China University of Science and Technology, Shanghai, China.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Qiu, Z.
    East China University of Science and Technology, Shanghai, China.
    Sui, Q.
    Shanghai Institute of Pollution Control and Ecological Security, Shanghai, China.
    A step forward towards synthesizing a stable and regeneratable nanocomposite for remediation of trichloroethene2018In: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 347, p. 660-668Article in journal (Refereed)
    Abstract [en]

    Synthesizing supported heterogeneous catalysts is always considered as a persistent approach for degradation of contaminants. However, the stability of these nanocomposites and improvement of process conditions influencing target pollutants degradation are still limited. Herein, on the basis of self-adhesive nature of polydopamine (PDA) and its strong electrostatic interaction with metallic ions, we synthesized a facile, stable, magnetically separable, and environmentally benign PDA decorated, reduced graphene oxide (rGO) supported Fe nanocatalyst (PDA@Fe/rGO). The effects of process variables (pH, PDA@Fe/rGO, and persulphate (PS) dose) on the degradation performance of trichloroethene (TCE), a model chlorinated organic pollutant selected in this study, were investigated. PDA not only encapsulated the host Fe/rGO magnetic particles but also exhibited high magnetization. PDA wrapping tremendously enhanced the thermal stability of nanocatalyst with just 24.1% weight loss at elevated temperature compared to solo Fe/rGO (40.2%). Moreover, TCE degradation mechanism was interpreted by ESR and radical scavenger tests, validating OH[rad], SO4 [rad]− and O2 [rad]− radicals being responsible for TCE degradation. Considering its eminent catalytic activity, simple synthesis approach and excellent kinetics, this recyclable and improved PDA assisted Fe/rGO nanocatalyst further opens a door for practical implementation in the field of contaminated groundwater remediation. 

  • 14.
    Farooq, Usman
    et al.
    East China Univ Sci & Technol, China..
    Danish, Muhammad
    East China Univ Sci & Technol, China..
    Lu, Shuguang
    East China Univ Sci & Technol, China..
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Gu, Xiaogang
    East China Univ Sci & Technol, China..
    Fu, Xiaro
    East China Univ Sci & Technol, China..
    Zhang, Xiang
    East China Univ Sci & Technol, China..
    Nasir, Muhammad
    COMSATS Inst Informat Technol, IRCBM, Lahore, Pakistan..
    Synthesis of nZVI@reduced graphene oxide: an efficient catalyst for degradation of 1,1,1-trichloroethane (TCA) in percarbonate system2017In: Research on chemical intermediates (Print), ISSN 0922-6168, E-ISSN 1568-5675, Vol. 43, no 5, p. 3219-3236Article in journal (Refereed)
    Abstract [en]

    Graphene-oxide-supported nano zero-valent iron (nZVI) composite (nZVI-rGO) was synthesized and tested as an efficient percarbonate activator for degradation of 1,1,1-trichloroethane (TCA). Significant dispersion of nZVI on the surface of reduced graphene oxide (rGO) was observed, with good limitation of nanoparticle agglomeration and aggregation. Good TCA degradation efficiency of 90% was achieved in 2.5 h in presence of 0.8 g/l nZVI-rGO catalyst and 30 mM sodium percarbonate (SPC) oxidant; however, excessive catalyst or oxidant concentration reduced the degradation efficiency. Investigation of reactive oxygen species using radical probe compounds as well as radical scavengers confirmed presence of hydroxyl (OH center dot) and superoxide () radicals that are responsible for the TCA degradation. The morphology and surface characteristics of the heterogeneous catalyst were analyzed by transmission electron microscopy and scanning electron microscopy. Brunauer-Emmett-Teller analysis revealed that the synthesized catalyst had large surface area and small particle size of 299.12 m(2)/g and 20.10 nm, respectively, compared with 5.33 m(2)/g and 1.12 A mu m for bare graphene oxide. X-ray diffraction analysis revealed good dispersion of nZVI on the surface of rGO. Fourier-transform infrared characteristic peaks confirmed strong attachment of Fe onto the rGO surface. Energy-dispersive spectroscopy analysis validated the stoichiometric composition of the prepared Fe/rGO material. In conclusion, use of nZVI-rGO-activated SPC could represent an alternative technique for remediation of TCA-contaminated groundwater.

  • 15.
    Inayat, A.
    et al.
    Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates.
    Ghenai, C.
    Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ammar, M.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Ayoub, M.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Hussin, M. N. B.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Parametric Study for Production of Dimethyl Ether (DME) As a Fuel from Palm Wastes2017In: Energy Procedia, Elsevier Ltd , 2017, p. 1242-1249Conference paper (Refereed)
    Abstract [en]

    Dimethyl Ether (DME) has been getting numerous attention as it's potential as the second generation bio-fuel. Traditionally DME is produced from the petroleum based stock which involves two steps of synthesis (methanol synthesis from the syngas and DME synthesis from methanol). DME synthesis via single step is one of the promising methods that has been developed. In Malaysia, due to the abundance of oil palm waste, it is a good candidate to be used as a feedstock for DME production. In this paper, single step process of DME synthesis was simulated and investigated using the Aspen HYSYS. Empty Fruit Bunch (EFB) from palm wastes has been taken as the main feed stock for DME synthesis. Four parameters (temperature, pressure, steam/biomass ratio and oxygen/biomass ratio) have been studied on the H2/CO ratio and DME yield. The results showed that optimum H2/CO ratio of 1.0 has been obtained when having an oxygen to biomass ratio (O/B) of 0.37 and steam to biomass ratio (S/B) of 0.23. The increment in the steam to biomass ratio increased the production of DME while the increment in oxygen to biomass ratio will cause reduction in DME production. © 2017 The Authors.

  • 16. M, Naqvi
    et al.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Black liquor gasification integrated in pulp and paper mills: A critical review2010In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 101, no 21, p. 8001-8015Article in journal (Other academic)
  • 17.
    Naqvi, M.
    et al.
    KTH.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Energy conversion performance of black liquor gasification to hydrogen production using direct causticization with CO2 capture2012In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 110, p. 637-644Article in journal (Refereed)
    Abstract [en]

    This paper estimates potential hydrogen production via dry black liquor gasification system with direct causticization integrated with a reference pulp mill. The advantage of using direct causticization is elimination of energy intensive lime kiln. Pressure swing adsorption is integrated in the carbon capture process for hydrogen upgrading. The energy conversion performance of the integrated system is compared with other bio-fuel alternatives and evaluated based on system performance indicators. The results indicated a significant hydrogen production potential (about 141 MW) with an energy ratio of about 0.74 from the reference black liquor capacity (about 243.5 MW) and extra biomass import (about 50 MW) to compensate total energy deficit. About 867,000 tonnes of CO2 abatement per year is estimated i.e. combining CO2 capture and CO2 offset from hydrogen replacing motor gasoline. The hydrogen production offers a substantial motor fuel replacement especially in regions with large pulp and paper industry e.g. about 63% of domestic gasoline replacement in Sweden. (C) 2012 Elsevier Ltd. All rights reserved.

  • 18.
    Naqvi, M.
    et al.
    KTH.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering.
    Synthetic natural gas (SNG) production at pulp mills from a circulating fluidized bed black liquor gasification process with direct causticization2010In: Proceedings of the 23rd International Conference on Efficiency, Cost, Optimization, Simulation, and Environmental Impact of Energy Systems, ECOS 2010, 2010, p. 83-91Conference paper (Refereed)
    Abstract [en]

    Synthetic natural gas (SNG) production from black liquor gasification (BLG) replacing conventional recovery cycle at chemical pulp mills is an attractive option to reduce CO2 emissions and replace fossil natural gas. This paper evaluates the potential of SNG production from a circulating fluidized bed BLG process with direct causticization by investigating synthesis gas composition, purity requirements for SNG and process integration with the reference pulp mill producing 1000 air dried tonnes (ADt) of pulp per day. The objective of this study is to estimate the integrated process efficiency from black liquor (BL) conversion to SNG and to quantify the differences in overall process efficiencies of various bio-refinery options. The models include a BLG Island including BL gasifier, synthesis gas cooling and cleaning unit, methanation with SNG upgrading and a power boiler. The result indicates a large potential of SNG production from BL but at a cost of additional biomass import to compensate energy deficit in terms of BL conversion to SNG. In addition, the study shows a significant CO2 abatement when CO2 capture is carried out in SNG upgrading and also reducing CO2 emissions when SNG potentially replaces fossil natural gas.

  • 19.
    Naqvi, M.
    et al.
    Royal Institute of Technology (KTH).
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    System analysis of dry black liquor gasification based synthetic gas production comparing oxygen and air blown gasification systems2013In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 112, p. 1275-1282Article in journal (Refereed)
    Abstract [en]

    The black liquor gasification based bio-fuel production at chemical pulp mill is an attractive option to replace conventional recovery boilers increasing system energy efficiency. The present paper studies circulating fluidized bed system with direct causticization using TiO2 for the gasification of the black liquor to the synthesis gas. The advantage of using direct causticization is the elimination of energy-intensive lime kiln which is an integral part of the conventional black liquor recovery system. The study evaluates the effects of gasifying medium i.e. oxygen or air, on the fluidized bed gasification system, the synthesis gas composition, and the downstream processes for the synthesis gas conversion to the synthetic natural gas (SNG). The results showed higher synthetic natural gas production potential with about 10% higher energy efficiency using oxygen blown gasification system than the air blown system. From the pulp mill integration perspective, the material and energy balance results in better integration of air blown system than the oxygen blown system, e.g. less steam required to be generated in the power boiler, less electricity import, and less additional biomass requirement. However, the air blown system still requires a significant amount of energy in terms of the synthesis gas handling and gas upgrading using the nitrogen rejection system.

  • 20.
    Naqvi, Muhammad
    KTH, Energiprocesser.
    Bio-refinery system integrated with pulp and paper mills using black liquor gasification2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mitigation of climate change and energy security are major driving forces for increased biomass energy utilization. The pulp and paper industry consumes a large proportion of biomass worldwide that include bark, wood residues, and black liquor. Due to the fact that modern pulp and paper industries have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to co-produce electricity, chemicals or bio-fuels together with pulp and paper products. There is a potential to export electricity or bio-fuels by improving today’s existing chemical pulp and paper mills integrating gasification technology.

    The present study evaluates the energy conversion performance of integrated black liquor gasification (BLG) within the chemical pulp mills in comparison with conventional pulp mill energy system. The objective is to investigate and compare various BLG technologies and bio-fuel production routes. The comparison is performed to identify the advantageous route based on system performance indicators e.g. bio-fuel production potential, fuel to product efficiency (FTPE), biomass import, overall system thermal energy efficiency, on-site CO2 reduction using carbon capture, and potential CO2 offsets from bio-fuel use in transport sector.

    The study on a variety of BLG configurations shows promising results for potential bio-fuel production offering significant contributions toward fossil fuel savings, emission reductions, and improved energy security. Methanol, synthetic natural gas (SNG) and dimethyl ether (DME) show promising features as potential fuel candidates. The comparative results show significantly larger bio-fuel production potential of black liquor conversion to SNG from catalytic hydrothermal gasification than DME, methanol or SNG production from the dry BLG (DBLG) and Chemrec BLG (CBLG) systems. The energy ratio of SNG production from the CHG system is higher than DME and methanol in the CBLG and the DBLG systems. When considering consequences of incremental biomass import, the DBLG system is far better than the CBLG and the CHG systems mainly due to the elimination of the lime kiln. Considerable reduction of on-site CO2 emissions could be achieved using CO2 capture and storage in the pulp mills. The CHG and the CBLG systems shows better performance results than the DBLG system comparing potential CO2 emissions offset from bio-fuels replacing fossil fuels.

  • 21.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Business feasibility of distributed off-grid electricity generation using mixed biomass compost: A scenario-based study2016Conference paper (Refereed)
  • 22.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Nizami, A. -S
    King Abdulaziz University, Saudi Arabia.
    Danish, M.
    State Environ. Protect. Key Lab. of Environmental Risk Assessment and Control on Chemical Process, ECUST, China.
    Naqvi, S.
    School of Chemical and Materials Engineering, NUST, Pakistan.
    Farooq, U.
    State Environ. Protect. Key Lab. of Environmental Risk Assessment and Control on Chemical Process, ECUST, China.
    Qureshi, A. S.
    Institute of Biotechnology and Genetic Engineering, University of Sindh, Pakistan.
    Rehan, M.
    King Abdulaziz University, Saudi Arabia.
    Gasification Integrated with Small Chemical Pulp Mills for Fuel and Energy Production2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 977-983Article in journal (Refereed)
    Abstract [en]

    Pulp mills without black liquor recovery cycle could play a major role in employing black liquor gasification (BLG) to produce transport fuels. In conventional chemical pulp mills, black liquor is burnt in recovery boilers to generate steam and electricity to meet energy demands. The inorganic chemicals are reused for the digestion process. However, the energy content and inorganic chemicals are not recovered in small scale pulp mills especially in the developing countries which do not employ recovery cycle. This study investigates the potential of synthetic natural gas (SNG) production by integrating BLG island with a reference pulp mill without chemical recovery cycle. The improvements in overall energy efficiency are evaluated using performance indicators such as biofuel production potential, integrated system’s efficiency, and energy ratios. The oxygen-blown circulating fluidized bed (CFB) gasification with direct causticization is integrated with reference pulp mill. The results showed considerable SNG production without external biomass import. However to compensate total electricity deficit, the electricity will be imported from the grid. There is a substantial CO2 abatement potential of combining CO2 capture using seloxol absorption, and CO2 mitigation from SNG by replacing gasoline. 

  • 23.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Karlstad University, Sweden.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Royal Institute of Technology (KTH), Sweden.
    Naqvi, S. R.
    NUST, Pakistan.
    Nizami, A. S.
    King Abdulaziz University, Saudi Arabia.
    Salman, Chaudhary Awais
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Danish, M.
    ECUST, China.
    Farooq, U.
    ECUST, China.
    Rehan, M.
    King Abdulaziz University, Saudi Arabia.
    Khan, Z.
    University of Glasgow, United Kingdom.
    Qureshi, A. S.
    University of Sindh, Pakistan.
    Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 224, p. 636-646Article in journal (Refereed)
    Abstract [en]

    This study aims to examine the potential substitute natural gas (SNG) production by integrating black liquor gasification (BLG) island with a small wheat straw-based non-wood pulp mills (NPM), which do not employ the black liquor recovery cycle. For such integration, it is important to first build knowledge on expected improvements in an overall integrated non-wood pulp mill energy system using the key performance indicators. O2-blown circulating fluidized bed (CFB) gasification with direct causticization is integrated with a reference small NPM to evaluate the overall performance. A detailed economic analysis is performed together with a sensitivity analysis based on variations in the rate of return due to varying biomass price, total capital investment, and natural gas prices. The quantitive results showed considerable SNG production but significantly reduced electricity production. There is a substantial CO2 abatement potential combining CO2 capture and CO2 mitigation from SNG use replacing compressed natural gas (CNG) or gasoline. The economic performance through sensitivity analysis reflects significant dependency on both substitute natural gas production and natural gas market price. Furthermore, the solutions to address the challenges and barriers for the successful commercial implementation of BLG based polygeneration system at small NPMs are discussed. The system performance and discussion on the real application of integrated system presented in this article form a vital literature source for future use by large number of small non-wood pulp industries.

  • 24.
    Naqvi, Muhammad Raza
    KTH, Energiprocesser.
    Analysing performance of bio-refinery systems by integrating black liquor gasification with chemical pulp mills2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mitigation of climate change and energy security are major driving forces for increased biomass utilization. The pulp and paper industry consumes a large proportion of the biomass worldwide including bark, wood residues, and black liquor. Due to the fact that modern mills have established infrastructure for handling and processing biomass, it is possible to lay foundation for future gasification based bio-refineries to poly-produce electricity, chemicals or bio-fuels together with pulp and paper products. There is a potential to export electricity or bio-fuels by improving energy systems of existing chemical pulp mills by integrating gasification technology.

    The present study investigates bio-fuel alternatives from the dry black liquor gasification (BLG) system with direct causticization and direct methane production from the catalytic hydrothermal gasification (CHG) system. The studied systems are compared with bio-fuel alternatives from the Chemrec BLG system and the improvements in the energy systems of the pulp mill are analyzed. The results are used to identify the efficient route based on system performance indicators e.g. material and energy balances to compare BLG systems and the conventional recovery boiler system, potential biofuel production together with biomass to biofuel conversion efficiency, energy ratios, potential CO2 mitigation combining on-site CO2 reduction using CO2 capture and potential CO2 offsets from biofuel use, and potential motor fuel replacement.

    The results showed that the dry BLG system for synthetic natural gas (SNG) production offers better integration opportunities with the chemical pulp mill in terms of overall material and energy balances. The biofuel production and conversion efficiency are higher in the CHG system than other studied configurations but at a cost of larger biomass import. The dry BLG system for SNG production achieved high biomass to biofuel efficiency and considerable biofuel production. The energy ratio is significant in the dry BLG (SNG) system with less biomass demand and considerable net steam production in the BLG island. The elimination of the lime kiln in the dry BLG systems resulted in reduced consequences of incremental biomass import and associated CO2 emissions. Hydrogen production in the dry BLG system showed the highest combined CO2 mitigation potential i.e. on-site CO2 capture potential and CO2 offset from biofuel replacing fossil fuel. The results also showed that the motor fuel replacement potential with SNG as compressed natural gas (CNG) replacing gasoline in the transport sector is significantly high in countries with large pulp industry.

  • 25.
    Naqvi, Muhammad Raza
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Complementing existing CHP plants using biomass for production of hydrogen and burning the residual gas in a CHP boiler2017In: Biofuels, ISSN 1759-7269, E-ISSN 1759-7277, no 6, p. 675-683Article in journal (Refereed)
    Abstract [en]

    Biorefinery systems at combined heat and power (CHP) plants represent numerous technical, economic and environmental benefits by utilizing the existing biomass handling infrastructure and producing biofuels together with heat and power. This study evaluates the economic feasibility of integrating biomass gasification to an existing CHP plant. Integration includes biomass gasification with downstream processing of the synthesis gas to remove particles and tars, condense out water, remove CO2 and use membrane filtration (polyamide membrane) to extract hydrogen. The separated residual gas components are utilized as extra fuel to the boiler in the CHP plant. Approximately 58.5 MWth of synthesis gas can be produced from a 90 MWth plant that represents 16.4 MWthof hydrogen. The rest of the heating value of produced synthesis gas (in the form of methane and carbon monoxide) is utilized for heat and power production. From an economic perspective, the production cost of hydrogen is estimated to be 0.125–0.75 €/kg. This can be compared to the US governments goal that H2 produced by wind power plus electrolyzers should have a maximum cost of 2.8–3.4 €/kg. The lower cost is for a unit operating at 3 bar and assuming that the costs are split between H2 and the syngas residue that is combusted, while the higher prices assume an atmospheric gasifier and all costs are put on the H2 produced.

  • 26.
    Naqvi, Muhammad Raza
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Farooq, Usman
    East China University of Science and Technology, China.
    Danish, Muhammad
    East China University of Science and Technology, China.
    Qureshi, Abdul Sattar
    University of Sindh, Pakistan.
    Prediction of oil extraction and yield from pyrolysis of rice bran using Response Surface Methodology (RSM)2016Conference paper (Refereed)
  • 27.
    Naqvi, Muhammad Raza
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jan, Yinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Salman Raza
    National University of Sciences & Technology (NUST), Pakistan.
    Off-grid electricity generation using mixed biomass compost:: A scenario-based study with sensitivity analysis2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 201, p. 363-370Article in journal (Refereed)
    Abstract [en]

    The aim of the study is to investigate the viability of waste gasification based off-grid electricity gener- ation utilizing mixed biomass composts (mixture of rice hulls with cow/poultry manure compost). The economic viability is studied on the different scenarios with considerations of (1) levels of electricity demand and utilization, (2) costs of variable biomass mix, (3) combined domestic and cottage industry business model, and (4) influence of governmental investments. The levelized cost of electricity (LCOE) is used as an indicator to measure the competitiveness of gasification based off-grid electricity genera- tion. The plant loading and the capacity factor have been used to assess the impacts of different scenarios. A sensitivity analysis of key parameters based on variations in annual operational hours, plant efficiency, plant cost and biomass supply cost is conducted. Based on levels of electricity demand and utilization, the LCOE ranged between 40 US cents/kW h and 29 US cents/kW h based on the plant loading and the capac- ity factor. The business revenue would not change considerably despite better plant utilization and reduced levelized cost of electricity if all the consumers, both basic or medium, are charged with the flat tariff. The part load operation will be costly despite considerably low capital investment per kW in com- parison with PV or solar based plants. There is a large potential of off-grid electricity generation but the estimated off-grid electricity price is found to be higher in all scenarios than average grid-based electric- ity tariff. Moreover, the challenges for the implementation of the real off-grid electricity generation plant are discussed. 

  • 28.
    Naqvi, Muhammad Raza
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Biorefinery: Production of Biofuel, Heat, and Power Utilizing Biomass2015In: Handbook of Clean Energy Systems / [ed] Prof. Jinyue Yan, United States: WILEY , 2015Chapter in book (Refereed)
    Abstract [en]

    The world’s energy consumption is projected to increase rapidly that will cause depletion of known fossil fuel resources, global warming and threat to future energy security. Biomass is likely to play a significant role in the future energy systems replacing conventional fuels due to strict regulations for reducing greenhouse gas (GHG) emissions as well as contributing as additional resource in the global energy mix. Biomass is processed in a bio-refinery facility for polygeneration of bio-energy products such as biofuels, heat, and power. Polygeneration system can be categorized based on various process routes producing electricity or biofuels or even providing only heat e.g. biomass gasification system, integrated biogas production with combined heat and power by treating organic waste, tri-generation systems etc. The successful commercialization of bio-refinery systems for polygeneration require pilot plants to demonstrate improvements in energy efficiency,  substantial biofuel, heat and power production potential from biomass together with reduced cost. From the sustainability perspective, bio-refinery systems show numerous economic, social and environmental benefits including diversification in biomass resources and bio-energy products.

  • 29.
    Naqvi, Muhammad Raza
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    First-Generation Biofuels2015In: HANDBOOK OF CLEAN ENERGY SYSTEMS / [ed] Prof. Jinyue Yan, UNITED STATES: John Wiley & Sons, 2015Chapter in book (Refereed)
    Abstract [en]

    Global energy demand is primarily dependent on the fossil fuel resources and the energy consumption is growing significantly that will cause increased concentration of greenhouse gases (GHG) in the atmosphere and depletion of known non-renewable energy resources that will cause threat to future energy security. The fossil resources are regarded as un-sustainable in terms of economy, ecology and environmental perspective. The increased utilization of biomass can play a significant role in replacing conventional fossil-based fuels and reducing emissions due to strict regulations for reducing greenhouse gas (GHG) emissions. Biomass based fuels can contribute as additional energy resource in the global energy mix. This chapter has discussed first generation biofuel, concept of bio-refineries, first generation feedstock derived bio-fuels, global first generation biofuel producing countries/regions and major sustainability challenges. The most common first generation biofuels include bio-ethanol, bio-diesel and bio-gas derived mainly from corn, sugarcane, soybean, vegetable oil, palm oil, wastes etc. From the sustainability perspective, first generation biofuels face numerous sustainability challenges including food and fuel competition, change in land-use, potential increased GHG emissions due to fossil fuel utilization in the upstream processes. First generation biofuels appears unsustainable because of the potential stress that their production places on food commodities. The economic aspects of first generation biofuel largely depend upon the type of feedstock and region where the feedstock have been cultivated and produced. Food prices will be affected due to increased production of energy crops that potentially compete with food crops for land use. In addition, the substantial production of biomass and conversion of biomass feedstock to biofuel may create new jobs and increase revenue from the agricultural sector.

  • 30. Naqvi, Muhammad
    et al.
    Suleman, Tahir M
    Jinyue, Yan
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    POTENTIAL OF SYNTHETIC GASPRODUCTION FROM BLACK LIQUORGASIFICATION BASED BIO-REFINERYSYSTEM INTEGRATED WITH KRAFTPULP MILLS IN PAKISTAN2013Conference paper (Refereed)
  • 31.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Department of Chemical Engineering and Technology, KTH.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Bio-refinery system in a pulp mill for methanol production with comparison of pressurized black liquor gasification and dry gasification using direct causticization2012In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 90, no 1, p. 24-31Article in journal (Other academic)
    Abstract [en]

    Black liquor gasification (BLG) for bio-fuel or electricity production at the modern pulp mills is a field incontinuous evolution and the efforts are considerably driven by the climate change, fuel security, andrenewable energy. This paper evaluates and compares two BLG systems for methanol production: (i) oxygenblown pressurized thermal BLG; and (ii) dry BLG with direct causticization, which have beenregarded as the most potential technology candidates for the future deployment. A key objective is toassess integration possibilities of BLG technologies with the reference Kraft pulp mill producing1000 air dried tonnes (ADt) pulp/day replacing conventional recovery cycle. The study was performedto compare the systems’ performance in terms of potential methanol production, energy efficiency,and potential CO2 reductions. The results indicate larger potential of black liquor conversion to methanolfrom the pressurized BLG system (about 77 million tonnes/year of methanol) than the dry BLG system(about 30 million tonnes/year of methanol) utilizing identical amount of black liquor available worldwide(220 million tDS/year). The potential CO2 emissions reduction from the transport sector is substantiallyhigher in pressurized BLG system (117 million tonnes/year CO2 reductions) as compared to dry BLGsystem (45 million tonnes/year CO2 reductions). However, the dry BLG system with direct causticizationshows better results when considering consequences of additional biomass import. In addition,comparison of methanol production via BLG with other bio-refinery products, e.g. hydrogen, dimethylether (DME) and bio-methane, has also been discussed.

  • 32.
    Naqvi, Muhammad
    et al.
    KTH, Energiprocesser.
    Yan, Jinyue
    KTH, Energiprocesser.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Integrated Synthetic Natural Gas Production from Oxygen Blown Dry Black Liquor Gasification Process with Direct Causticization2011Conference paper (Refereed)
  • 33.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH, Energiprocesser.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Sustainability Aspects of Transport Bio-fuels from Black liquor gasification – a System AnalysisIn: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777Article in journal (Other academic)
  • 34.
    Naqvi, Muhammad
    et al.
    KTH.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Synthetic gas production from dry black liquor gasification process using direct causticization with CO2 capture2012In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 97, p. 49-55Article in journal (Refereed)
    Abstract [en]

    Synthetic natural gas (SNG) production from dry black liquor gasification (DBLG) system is an attractive option to reduce CO2 emissions replacing natural gas. This article evaluates the energy conversion performance of SNG production from oxygen blown circulating fluidized bed (CFB) black liquor gasification process with direct causticization by investigating system integration with a reference pulp mill producing 1000 air dried tonnes (ADt) of pulp per day. The direct causticization process eliminates use of energy intensive lime kiln that is a main component required in the conventional black liquor recovery cycle with the recovery boiler. The paper has estimated SNG production potential, the process energy ratio of black liquor (BL) conversion to SNG, and quantified the potential CO2 abatement. Based on reference pulp mill capacity, the results indicate a large potential of SNG production (about 162 MW) from black liquor but at a cost of additional biomass import (36.7 MW) to compensate the total energy deficit. The process shows cold gas energy efficiency of about 58% considering black liquor and biomass import as major energy inputs. About 700 ktonnes per year of CO2 abatement i.e. both possible CO2 capture and CO2 offset from bio-fuel use replacing natural gas, is estimated. Moreover, the SNG production offers a significant fuel replacement in transport sector especially in countries with large pulp and paper industry e.g. in Sweden, about 72% of motor gasoline and 40% of total motor fuel could be replaced.

  • 35.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Royal Institute of Technology (KTH), Stockholm, Sweden.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, S. R.
    National University of Sciences and Technology (NUST), Islamabad, Pakistan.
    Waste Biomass Gasification Based off-grid Electricity Generation: A Case Study in Pakistan2016In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 103, p. 406-412Article in journal (Refereed)
    Abstract [en]

    The objective is to investigate the waste gasification based off-grid electricity generation in developing countries like Pakistan utilizing mixed biomass composts (mixture of agricultural wastes including rice hulls and wheat straw with cow/poultry manure compost). Different scenarios are compared; (1) levels of electricity demand and utilization, (2) costs for variable biomass mix, (3) combined domestic and cottage industry business model. The levelized cost of electricity (LCOE) is used as an indicator to measure the competitiveness of off-grid electricity generation. There is a large potential of off-grid electricity generation. However, the estimated off-grid electricity price is found to be higher in all scenarios than average governmental electricity tariff.

  • 36.
    Naqvi, Muhammad
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Danish, Muhammad
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai, Peoples R China..
    Farooq, Usman
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai, Peoples R China..
    Lu, Shuguang
    E China Univ Sci & Technol, State Environm Protect Key Lab Environm Risk Asse, Shanghai, Peoples R China..
    An experimental study on hydrogen enriched gas with reduced tar formation using pre-treated olivine in dual bed steam gasification of mixed biomass compost2016In: International journal of hydrogen energy, ISSN 0360-3199, E-ISSN 1879-3487, Vol. 41, no 25, p. 10608-10618Article in journal (Refereed)
    Abstract [en]

    The study investigated the effects of pre-treated olivine in dual bed steam gasification (DBSG) of biomass compost in order to produce H-2 enriched synthesis gas with significantly reduced tar formation. The DBSG employed circulating fluidized bed (CFB) of silica sand as first stage and fixed catalytic bed of pre-treated olivine as second stage. The mixed biomass compost contained 15-20 wt. % of agri-residues (mainly wheat straw) and 80-85 wt. % of cow manure. The study compared the synthesis gas distribution and tar reductions using pre-treated olivine in the DBSG scheme with Ni-Al based DBSG scheme. The effects of operating condition on the synthesis gas distribution and tar formation are studied such as: (i) effect of steam to biomass ratio, (ii) effects of relative oxidation (relox), (iii) operating temperature of the reactor, (iv) performance and comparison of employed catalysts, and (v) yield of synthesis gas together with carbon conversion efficiency. Experimental analysis showed that H-2 concentration obtained from pre-treated olivine based DBSG is considerably higher than H-2 produced from compared gasification schemes. The H-2 production is favoured at higher temperatures and higher SBR under the influence of pre-treated olivine catalyst. However, the conditions are less advantageous for the production of CO and CH4. Among all experiments, the synthesis gas composition obtained at SBR = 1.40 and at 800 degrees C consisted of highest H-2 concentration (35 vol.% d.n.f) in the pre-treated olivine DBSG. Higher steam to biomass ratio (SBR) resulted in lower cold gas energy efficiency and lower heating value of the synthesis gas mainly due to large steam content in the gas. The tar removal efficiency of 98% is achieved with the pre-treated olivine DBSG system. The total tar content is significantly reduced (approximate to 40%) in the DBSG with pre-treated olivine. Higher relative oxidation resulted in increased concentration of CO2 in the synthesis gas due to increased partial oxidation of organic matter in the gasifier. The pre-treated olivine catalyst in the DBSG consistently promoted the process of steam reforming and tar cracking and thus improved the quality of the syngas by limiting the tar contents.

  • 37.
    Naqvi, Muhammad
    et al.
    Department of Chemical Engineering/Energy Processes, Royal Institute of Technology.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Fröling, M.
    Department of Chemical and Biological Engineering, Chalmers University of Technology.
    Bio-refinery system of DME or CH4 production from black liquor gasification in pulp mills2010In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 101, no 3, p. 937-944Article in journal (Refereed)
    Abstract [en]

    There is great interest in developing black liquor gasification technology over recent years for efficient recovery of bio-based residues in chemical pulp mills. Two potential technologies of producing dimethyl ether (DME) and methane (CH4) as alternative fuels from black liquor gasification integrated with the pulp mill have been studied and compared in this paper. System performance is evaluated based on: (i) comparison with the reference pulp mill, (ii) fuel to product efficiency (FTPE) and (iii) biofuel production potential (BPP). The comparison with the reference mill shows that black liquor to biofuel route will add a highly significant new revenue stream to the pulp industry. The results indicate a large potential of DME and CH4 production globally in terms of black liquor availability. BPP and FTPE of CH4 production is higher than DME due to more optimized integration with the pulping process and elimination of evaporation unit in the pulp mill.

  • 38.
    Naqvi, S. R.
    et al.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Jamshaid, S.
    Yeungnam University, Gyeongsan, South Korea.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Farooq, W.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Niazi, M. B. K.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Aman, Z.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Zubair, M.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Ali, M.
    National University of Sciences&Technology, Islamabad, Pakistan.
    Shahbaz, M.
    Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Inayat, A.
    University of Sharjah, United Arab Emirates.
    Afzal, W.
    University of Aberdeen, Aberdeen, Scotland, United Kingdom.
    Potential of biomass for bioenergy in Pakistan based on present case and future perspectives2018In: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, p. 1247-1258Article in journal (Refereed)
    Abstract [en]

    Future energy security and environmental issues are major driving forces for increased biomass utilization globally and especially in developing countries like Pakistan. For efficient utilization of indigenous biomass resources in the future energy mix, it is important to gain knowledge of current energy system in various sectors. Some of the technologies and initiatives are under development to achieve transition from non-renewable resources to renewable resources, and reducing fossil fuel dependency and greenhouse gas emissions. Recently, number of proposals has been presented for the development of sustainable biofuels production methods for promise for accelerating a shift away from an unsustainable approach to possible sustainable production practices or a sustainable social, economic and environment. This article presents an extensive literature review of the biomass-based renewable energy potential in Pakistan based on current energy scenario and future perspectives. It also highlights the availability of the indigenous and local biomass resources and potential biomass conversion technologies to convert such resources to bioenergy. The drivers for utilization of indigenous biomass resources in future energy mix and challenges regarding awareness among stakeholders and R&D to fill knowledge gaps are economically restraints. The article concludes with suggestions on future directions and policies for effective implementation of biomass based renewable energy production.

  • 39.
    Naqvi, S. R.
    et al.
    School of Chemical and Materials Engineering, National University of Sciences and Technology, Islamabad, Pakistan.
    Uemura, Y.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Malaysia.
    Yusup, S.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Tronoh, Malaysia.
    Nishiyama, N.
    Department of Materials Engineering, Graduate School of Engineering Science, Osaka University, Toyonaka, Japan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Catalytic Consequences of Micropore Topology on Biomass Pyrolysis Vapors over Shape Selective Zeolites2017In: Energy Procedia, Elsevier Ltd , 2017, p. 557-561Conference paper (Refereed)
    Abstract [en]

    Research on utilization of abundant rice residue for valuable bioenergy products is still not explored completely. A simple, robust, cheap and one step fast pyrolysis reactor is still a key demand for production of bioenergy products, i.e. high quality bio-oil and bio char. Bio-oil produced from fast pyrolysis has poor quality (e.g. acidic and highly oxygenated). Catalytic fast pyrolysis using zeolites in the fast pyrolysis process effectively reduce the oxygen content (no H2 required). In this paper, zeolites having a variety of pore size and shape (small pore: SAPO-34 (0.56), Ferriertite (20), medium pore: ZSM-5 (23), MCM-22 (20), ITQ-2 (20) and large pore zeolite Mordenite (20) were tested in a drop type fixed-bed pyrolyzer. The catalytic deoxygenation is conducted at 450°C at the catalyst/biomass ratio of 0.1. Zeolite catalysts, its pore size and shape could influence largely on deoxygenation. Small pore zeolites did not produce aromatics while medium pore zeolites formed higher amount of aromatics. ZSM-5 and ITQ-2 zeolites were especially efficient for the higher deoxygenation of biomass pyrolysis vapors due to better pore dimension and higher acidity. © 2017 The Authors.

  • 40.
    Naqvi, Salman Raza
    et al.
    Natl Univ Sci & Technol NUST, Sch Chem & Mat Engn, Islamabad, Pakistan..
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Catalytic fast pyrolysis of rice husk: Influence of commercial and synthesized microporous zeolites on deoxygenation of biomass pyrolysis vapors2018In: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 42, no 3, p. 1352-1362Article in journal (Refereed)
    Abstract [en]

    Research on utilization of abundant rice residue for valuable bioenergy products is still not explored completely. A simple, robust, cheap, and one-step fast pyrolysis reactor is still a key demand for production of bioenergy products, ie, high quality bio-oil and biochar. Bio-oil extracted from fast pyrolysis does not have adequate quality (eg, acidic and highly oxygenated). Catalytic fast pyrolysis using zeolites in the fast pyrolysis process effectively reduces the oxygen content (no H-2 required). In this paper, the zeolites with different pore sizes and shapes (small pore, SAPO-34 (0.56) and ferrierite (30); medium pore, ZSM-5 (30), MCM-22 (30), and ITQ-2 (30); and large pore zeolite, mordenite (30)) were tested in a drop-type fixed-bed pyrolyzer. Catalytic deoxygenation is conducted at 450 degrees C at the catalyst/biomass ratio of 0.1. Zeolite catalysts, its pore size and shape, could influence largely on deoxygenation. It was found that the small pore zeolites did not produce aromatics as compared to higher amount of aromatics formed in case of medium pore zeolites. ZSM-5 and ITQ-2 zeolites were especially efficient for the higher deoxygenation of biomass pyrolysis vapors due to better pore dimension and higher acidity.

  • 41.
    Naqvi, Salman Raza
    et al.
    Univ Teknol PETRONAS, Tronoh, Malaysia.
    Uemura, Yoshimitu
    Univ Teknol PETRONAS, Tronoh, Malaysia.
    Yusup, Suzana
    Univ Teknol PETRONAS, Tronoh, Malaysia.
    Sugiur, Y.
    Osaka Univ, Japan.
    Nishiyama, N.
    Osaka Univ, Japan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    The Role of Zeolite Structure and Acidity in Catalytic Deoxygenation of Biomass Pyrolysis Vapors2015In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, p. 793-800Article in journal (Refereed)
    Abstract [en]

    Catalytic upgrading of paddy husk was performed over 10-MR zeolites (MCM-22, ITQ-2 and ZSM-5) in a drop type fixed-bed reactor. This work investigated the role of structure and acidity of zeolites on pyrolysis-oil yield and degree of deoxygenation. Catalytic pyrolysis experiments were carried out at the catalyst/biomass ratio (0.05 -0.5) at temperature of 450 degrees C. The oil yield decreased by using catalyst and this decrease oil yield is attributed to catalytic cracking of bio-oil vapor on the catalyst. The route for deoxygenation of pyrolysis vapors was identified to be dehydration, decarboxylation and decarboxylation. ITQ-2 showed high degree of deoxygenation as compare to MCM-22 which is due to more accessible external active sites of ITQ-2. The organics yield in pyrolysis oil was highest with ZSM-5 in comparison with other zeolites. 

  • 42.
    Nizami, A. -S
    et al.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Rehan, M.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ouda, O.
    Janabadra University, Yogyakarta, Indonesia.
    Shahzad, K.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Syamsiro, M.
    Janabadra University, Yogyakarta, Indonesia.
    Waqas, M.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Miandad, R.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Asam, Z. -U.-Z.
    University of Gujrat, Gujrat, Pakistan.
    Mohammad Ismail, I.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Energy, Economic and Environmental Savings by Waste Recycling: A Case Study of Madinah City2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 910-915Article in journal (Refereed)
    Abstract [en]

    In the Kingdom of Saudi Arabia (KSA), millions of worshippers come from across the globe to perform religious rituals of Pilgrimage (Hajj) and Umrah. Madinah-tul-Munawara is one of the holiest city, where pilgrims come after performing rituals in Makkah. In this city, most of the collected municipal solid waste (MSW) is disposed of in the landfills after a partial recycling of paper, cardboard, and metals (∌10-20% of total MSW). The Saudi’s government has recently launched a new policy of Vision 2030, which outlined the safeguard of local environment through increased efficiency of waste recycling and management, pollution prevention strategies and generating renewable energy from indigenous sources, including the waste. Currently, the recycling practices in KSA are mainly regulated by an informal sector through waste pickers or waste scavengers. This has led to the need of recycling schemes, especially in the holiest cities of Makkah and Madinah through a public-private partnership (PPP). Huge amounts of energy can be conserved, that would otherwise be spent on raw material extraction, transportation, and manufacturing of materials, through recycling into the same materials. Around 10,009 TJ of energy can be saved through recycling of 24.21% of MSW in Madinah city, including glass, metals, aluminum, cardboard, and paper. It is estimated that around 10,200 tons of methane (CH4) emissions and 254,600 Mt.CO2 eq. of global warming potential (GWP) can also be saved. In addition, carbon credit revenue of US $5.92 million, and landfill diversion worth of US $32.78 million can be achieved with a net revenue of US $49.01 million every year only by recycling 24.21% of MSW in Madinah city. The waste recycling doesn’t require high technical skills and labor, and complicated technologies for large-scale implementation, and therefore, can be implemented easily in the holiest cities of Makkah and Madinah to achieve multiple economic and environmental benefits. 

  • 43.
    Nizami, A. S.
    et al.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Rehan, M.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Waqas, M.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ouda, O. K. M.
    Prince Mohamed Bin Fahd Univ, Al Khobar, Saudi Arabia.
    Shahzad, K.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Miandad, R.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Khan, M. Z.
    Aligarh Muslim Univ, Uttar Pradesh, India.
    Syamsiro, M.
    Janabadra Univ, Indonesia.
    Ismail, I. M. I.
    King Abdulaziz Univ, CEES, Jeddah, Saudi Arabia.
    Pant, Deepak
    Flemish Inst Technol Res VITO, Mol, Belgium.
    Waste biorefineries: Enabling circular economies in developing countries2017In: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 241, p. 1101-1117Article in journal (Refereed)
    Abstract [en]

    This paper aims to examine the potential of waste biorefineries in developing countries as a solution to current waste disposal problems and as facilities to produce fuels, power, heat, and value-added products. The waste in developing countries represents a significant source of biomass, recycled materials, chemicals, energy, and revenue if wisely managed and used as a potential feedstock in various biorefinery technologies such as fermentation, anaerobic digestion (AD), pyrolysis, incineration, and gasification. However, the selection or integration of biorefinery technologies in any developing country should be based on its waste characterization. Waste biorefineries if developed in developing countries could provide energy generation, land savings, new businesses and consequent job creation, savings of landfills costs, GHG emissions reduction, and savings of natural resources of land, soil, and groundwater. The challenges in route to successful implementation of biorefinery concept in the developing countries are also presented using life cycle assessment (LCA) studies.

  • 44.
    Qureshi, A. S.
    et al.
    University of Sindh, Jamshoro, Pakistan.
    Khushk, I.
    University of Sindh, Jamshoro, Pakistan.
    Naqvi, S. R.
    National University of Sciences and Technology, Islamabad, Pakistan.
    Simiar, A. A.
    Donghua University, Shanghai, China.
    Ali, C. H.
    University of Engineering and Technology, KSK Campus, Lahore, Pakistan.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Danish, M.
    State Environ. Protect. Key Lab. of Environmental Risk Assessment and Control on Chemical Process, ECUST, Shanghai, China.
    Ahmed, A.
    Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan.
    Majeed, H.
    Jiangnan University, Wuxi, China.
    Mir Jatt, A. N.
    University of Sindh, Jamshoro, Pakistan.
    Rehan, M.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Nizami, A. -S
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Fruit Waste to Energy through Open Fermentation2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 904-909Article in journal (Refereed)
    Abstract [en]

    This study aims to examine the nonsterilized fermentation conditions for coproduction of pectinases and lipase enzymes using several fruit wastes as an energy source. Thermophilic fungal strain, Penicillium expansum CMI 39671 was used as a fermenting strain. The effect of process conditions including; nitrogen sources, pH, temperature, time and moisture contents, on the production of both enzymes were studied. The highest activities of pectinase and lipase (2817, 1870 U/g dry substrate) enzymes were found with orange peel feedstock, whereas the lowest activities of 1662 U/g and 1266 U/g were found with banana peel and papaya peel feedstocks respectively. Overall, pectinase showed higher enzymatic activities than lipase enzymes, both having similar increasing and decreasing trends, at all studied conditions. The optimum process conditions of peptone as a nitrogen source, pH 7, 40°C, 5 days and 70% moisture contents, were found to show highest enzymatic activities for both enzymes. The orange peel feedstock showed no significant difference in both enzymes’ activities at sterilized and nonnotarized process conditions. Pectinase and lipase enzymes showed (13791 U/g) and (8114 U/g) for sterilized and (14091 U/g) and (8324 U/g) for nonnotarized process conditions respectively. In addition, the fungal strains also produce bacteriocin-like compounds that could inhibit microbial growth. These findings will help to design and develop robust, cost-effective and less energy intensive enzyme production processes and consequently an efficient fruit waste to energy system through open fermentation.

  • 45.
    Rehan, M.
    et al.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Nizami, A. -S
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Asam, Z. -U.-Z.
    University of Gujrat, Gujrat, Pakistan.
    Ouda, O. K. M.
    Prince Mohamed Bin Fahd University, Al Khobar, Saudi Arabia.
    Gardy, J.
    University of Leeds, Leeds, United Kingdom.
    Raza, G.
    University of Leeds, Leeds, United Kingdom.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Mohammad Ismail, I.
    King Abdulaziz University, Jeddah, Saudi Arabia.
    Waste to Energy: A Case Study of Madinah City2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 688-693Article in journal (Refereed)
    Abstract [en]

    The concept of energy from waste is getting popular nowadays across the globe, as being capable of producing multi fuels and value-added products from different fractions of municipal solid waste (MSW). The energy recovery technologies under this concept are anaerobic digestion (AD), pyrolysis, transesterification, refuse derived fuel (RDF) and incineration. This concept is very relevant to implementation in countries like Saudi Arabia, who wants to cut their dependence on oil. Moreover, the waste to energy becomes the imperative need of the time because of new governmental policy ’Vision 2030’ that firmly said to produce renewable energy from indigenous sources of waste, wind and solar and due to given situations of Hajj and Umrah with massive amounts of waste generation in a short period. This study focused on two waste to energy technologies, AD and pyrolysis for food (40% of MSW) and plastic (20% of MSW) waste streams respectively. The energy potential of 1409.63 and 5619.80 TJ can be produced if all of the food and plastic waste of the Madinah city are processed through AD and pyrolysis respectively. This is equivalent to 15.64 and 58.81 MW from biogas and pyrolytic oil respectively or total 74.45 MW of continuous electricity supply in Madinah city throughout the whole year. It has been estimated that the development of AD and pyrolysis technologies will also benefit the economy with net savings of around US $63.51 and US $53.45 million respectively, totaling to an annual benefit of US $116.96 million. Therefore, in Saudi Arabia and particularly in Holiest cities of Makkah and Madinah the benefits of waste to energy are several, including the development of renewable-energy, solving MSW problems, new businesses, and job creation and improving environmental and public health.

  • 46.
    Salman, Chaudhary Awais
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Royal Institute of Technology, Stockholm, Sweden.
    A polygeneration process for heat, power and DME production by integrating gasification with CHP plant: Modelling and simulation study2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, p. 1749-1758Article in journal (Refereed)
    Abstract [en]

    Biofuels are a good substitute for the transport sector petroleum fuels to minimize carbon footprint and greenhouse gases emissions. Di-Methyl Ether (DME) is one such alternative with properties similar to liquefied petroleum gas but with lower SOx, NOx, and particulate emissions. In this work, a polygeneration process, integrating an existing combined heat and power (CHP) plant with biomass gasification to synthesize DME, is proposed and modelled. Process integration is based on a hypothesis that the CHP plant provides the necessary heat to run the co-located gasification plant for DME synthesis and the waste heat from the gasification process is recovered and transferred to the CHP plant. The feed for gasification is taken as refuse derived fuel (RDF) instead of conventional wood derived biomass. The process integration leads to higher overall combined efficiency (up to 71%) which is greater than stand-alone efficiencies (up to 63%) but lower than stand-alone CHP plant efficiency (73.2%). The further technical evaluation shows that the efficiency of the polygeneration process is depends heavily on the gasifier capacity integrated with the existing CHP plant and also on the conversion route selected for DME synthesis i.e. recycling of unconverted syngas to the DME reactor or transferring it to the boiler of the CHP plant. The simulation results also indicate that once-through conversion yields less DME than recycling, but at the same time, once-through conversion affects the district heat and electric power production of the CHP plant lesser than by using the recycling route.

  • 47.
    Salman, Chaudhary Awais
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Karlstad University, Sweden.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. Royal Institute of Technology, Stockholm, Sweden.
    Gasification process integration with existing combined heat and power plants for polygeneration of dimethyl ether or methanol: A detailed profitability analysis2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 226, p. 116-128Article in journal (Refereed)
    Abstract [en]

    Combustion of waste for cogeneration of heat and power is the most convenient and practical choice to carry out through combined heat and power (CHP) plants. But, seasonal variation in heat demand throughout the year affects the operation of CHP plants. This fluctuation in the CHP operation cause less annual operating hours for the plant equipment and is also not profitable for stakeholders. This study aims to assess the technical potential of integrated gasification process with existing CHP plants for either dimethyl ether (DME) or methanol production through refuse-derived fuel (RDF). Process integration considers that the CHP plant provides the necessary heat for biofuel synthesis during off-peak hours. Mass and heat integration methods are used to develop and simulate the polygeneration processes for heat, power, and biofuel production. Both technical and economic indicators are reported and compared to assess the potential for both biofuels through process integration. Annual operation data of a real CHP plant has been extracted to evaluate the integrated processes. A flexible gasification configuration is selected for the integrated approach i.e. CHP runs at full load to provide the heat demand and only the excess heat of CHP plant is utilized for biofuel production. The energetic efficiencies of the polygeneration systems are compared with the standalone systems. Technical analysis of process integration shows the enhancement of the operational capacity of CHP during off-peak hours and it can produce biofuels without compromising the annual heat demand. Production of methanol through process integration shows ∼67% energetic efficiency while methanol production gives ∼65%. The efficiencies are higher than standalone DME and methanol processes (51% and 53%, respectively) but lower than standalone CHP plant i.e. 81%, however the process integration increases the operating time of the CHP plant with more economic benefits. Economic analysis coupled with uncertainty analysis through Monte Carlo simulations shows that by integrating CHP with gasifier to produce biofuels is significantly profitable as compared with only heat and electricity production. But, DME as a potential product shows more economic benefits than methanol. The uncertainty analysis through Monte Carlo simulations shows that the profitable probability of DME as a product in future is also greater than methanol due to higher DME selling price. The uncertainty analysis further shows that prices of DME and methanol with waste biomass prices in future will have a greater impact on the economic performance of the proposed polygeneration process. 

  • 48.
    Salman, Chaudhary Awais
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Yan, Jinyue
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Impact of retrofitting existing combined heat and power plant with polygeneration of biomethane: A comparative techno-economic analysis of integrating different gasifiers2017In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 152, p. 250-265Article in journal (Refereed)
    Abstract [en]

    It is vital to identify and evaluate the optimal gasifier configuration that could be integrated with existing or new combined heat and power (CHP) plants to maximize the utilization of boiler operating capacity during off-peak hours with minimal effect on the boiler performance. This study aims to identify technically and economically most suitable gasification configuration and the reasonable operational limits of a CHP plant when integrated with different types of gasifiers. The selected gasifiers for the study are, (i) indirectly heated dual fluidized bed gasifier (DFBG), (ii) directly heated circulating fluidized bed gasifier (CFBG), and (iii) entrained flow gasifier (EFG). The gasifiers are selected on their ability to produce high-quality syngas from waste refused derived fuel (RDF). The syngas from the gasifiers is utilized to produce biomethane, whereas the heat and power from the CHP plant are consumed to run the gasification process. A detailed techno-economic analysis is performed using both flexible capacity and fixed capacity gasifiers and integrated with the CHP plant at full load. The results reveal that the integration leads to increase in operating time of the boiler for all gasifier configurations. The indirectly heated DFBG shows the largest biomethane production with less impact on the district heat and power production. Extra heat is available for biomethane production when the district heat and biomethane are prioritized, and the electric power is considered as a secondary product. Furthermore, the economic indicators reflect considerable dependency of integrated gasification performance on variable prices of waste biomass and biomethane. 

  • 49.
    Yan, Jinyue
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Raza Naqvi, Muhammad
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. KTH.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Bioenergy polygeneration, carbon capture and storage related to the pulp and paper industry and power plants2013In: Biomass as Energy Source: Resources, Systems and Applications / [ed] Erik Dahlquist, Taylor & Francis Group, 2013, 1, p. 163-176Chapter in book (Refereed)
    Abstract [en]

     

    The use of energy is approximately 140 000 TWh per year globally. It is then interesting to note that biomass production is approximately 270 000 TWh/year, or roughly twice as much. This shows that biomass is not a marginal energy resource but more than enough to cover all our needs for both energy and food, if just the biomass is used efficiently. There has been a lot of discussion about using food for energy. This is quite relevant, and if we look at all resources like agricultural and forestry waste, the need to use food for energy is not needed. We can cover all our needs anyhow. The resources we have available and some other aspects like using the energy efficiently is covered in this book. One way of using energy efficiently is to use waste biomass or cellulosic materials in bio refineries, where production of fibers and products from fibers is combined with production of most chemicals we need in our daily life. This includes clothes, soap, perfume, medicines etc. Conventional pulp and paper applications are also covered. But it also includes bio-fuel for vehicles and even fuel for aviation is covered. It also includes production of heat, cool and electricity. That is, biomass can cover all our needs. The difficulty is to use the resources efficiently without harming the productivity long term. This book has the aim to give facts and inspiration to professionals like engineers and researchers, students as well as those working for different type of authorities or societal organizations.

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