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Salman, C. A., Dahlquist, E., Thorin, E., Kyprianidis, K. & Avelin, A. (2019). Future directions for CHP plants using biomass and waste - Adding production of vehicle fuels. In: E3S Web of Conferences: . Paper presented at 2019 SUstainable PolyEnergy Generation and HaRvesting, SUPEHR 2019, 4 September 2019 through 6 September 2019. EDP Sciences, Article ID 01006.
Open this publication in new window or tab >>Future directions for CHP plants using biomass and waste - Adding production of vehicle fuels
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2019 (English)In: E3S Web of Conferences, EDP Sciences , 2019, article id 01006Conference paper, Published paper (Refereed)
Abstract [en]

In Northern Europe, the production of many biobased CHP plants is getting affected due to the enormous expansion of wind and solar power. In addition, heat demand varies throughout the year, and existing CHP plants show less technical performance and suffer economically. By integrating the existing CHP plants with other processes for the production of chemicals, they can be operated more hours, provide operational and production flexibility and thus increase efficiency and profitability. In this paper, we look at a possible solution by converting an existing CHP plant into integrated biorefinery by retrofitting pyrolysis and gasification process. Pyrolysis is retrofitted in an existed CHP plant. Bio-oil obtained from pyrolysis is upgraded to vehicle grade biofuels. Gasification process located upfront of CHP plant provides the hydrogen required for upgradation of biofuel. The results show that a pyrolysis plant with 18 ton/h feed handling capacity (90 MWth), when integrated with gasification for hydrogen requirement and CHP plant for heat can produce 5.2 ton/h of gasoline/diesel grade biofuels. The system integration gives positive economic benefits too but the annual operating hours can impact economic performance. 

Place, publisher, year, edition, pages
EDP Sciences, 2019
National Category
Energy Systems
Identifiers
urn:nbn:se:mdh:diva-45259 (URN)10.1051/e3sconf/201911301006 (DOI)2-s2.0-85071879296 (Scopus ID)
Conference
2019 SUstainable PolyEnergy Generation and HaRvesting, SUPEHR 2019, 4 September 2019 through 6 September 2019
Available from: 2019-09-19 Created: 2019-09-19 Last updated: 2019-09-19Bibliographically approved
Hakalehto, E. & Dahlquist, E. (2018). A microbiological approach to the ecosystem services. In: Microbiological Environmental Hygiene: (pp. 433-474). Nova Science Publisher Inc.
Open this publication in new window or tab >>A microbiological approach to the ecosystem services
2018 (English)In: Microbiological Environmental Hygiene, Nova Science Publisher Inc. , 2018, p. 433-474Chapter in book (Other academic)
Abstract [en]

Man has always exploited the environment for securing human life and culture. This “tradition” is both embedded into our instincts as well as a mode of behavior and a learnt method of survival in our societies. However, alongside with the globalization of the economy, internationalization, industrialization and population growth, the consequences of the one-sided approach of the past have become unbearable for the environment. Consequently, in order to maintain life on earth in its current form, we should establish new thinking and modes of action. Therefore, the survival strategies for Mankind should inherently contain the strive for sustainability, as well as the tendency to avoid past mistakes, and to repair them instantaneously whenever possible. The agricultural tradition of different nations leans on the centuries old wisdom of human civilization in a good sense. For example, the East Asian agricultural societies have learnt to handle each piece of land in their possession in an individual manner, taking into account the local environmental conditions. These principles are now more and more unanimously accepted, at least in theory. Also, the industrial ecosystem needs to be functioning in the natural way, and in balance with the environment. This is a necessity in the reversion or prevention of any developing environmental catastrophes that could wait behind the corner. As the major vehicles for the circulation of matter, microbes are in a key position and provide means for finding the solutions to serve the global ecosystems. In the aftermath of a vast environmental crisis, namely the oil leakage from the “Deepwater Horizon” oil platform well in the Mexican Gulf in the year 2010, it was noticed that the dramatic consequences of the spill were mitigated and the worst scenario of destruction avoided thanks to the cleaning actions of the marine micro-organisms. This was a positive result both ecologically and in economic sense. It further encouraged the scientists to find and isolate microbial strains which could be used for such operations. Although the natural microflora compensated and mitigated the effects of the Deepwater Horizon accident surprisingly well in 2010, there have been observations and concerns about the long term effects of this ecocatastroph (Geggel, 2015).

Place, publisher, year, edition, pages
Nova Science Publisher Inc., 2018
National Category
Environmental Sciences related to Agriculture and Land-use
Identifiers
urn:nbn:se:mdh:diva-39982 (URN)2-s2.0-85048411356 (Scopus ID)9781536131796 (ISBN)9781536131789 (ISBN)
Available from: 2018-06-21 Created: 2018-06-21 Last updated: 2018-06-21Bibliographically approved
Wang, C., Yan, J., Marnay, C., Djilali, N., Dahlquist, E., Wu, J. & Jia, H. (2018). Distributed Energy and Microgrids (DEM). Applied Energy, 210, 685-689
Open this publication in new window or tab >>Distributed Energy and Microgrids (DEM)
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2018 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 210, p. 685-689Article in journal, Editorial material (Refereed) Published
Place, publisher, year, edition, pages
Elsevier Ltd, 2018
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-37598 (URN)10.1016/j.apenergy.2017.11.059 (DOI)000419813100054 ()2-s2.0-85038265408 (Scopus ID)
Available from: 2017-12-28 Created: 2017-12-28 Last updated: 2018-01-26Bibliographically approved
Trosten, T., Moskull, H., Lindahl, M., Dahlquist, E. & Maher, A. (2018). Energy Optimal Switching Frequency for a 750V Metro Traction Drive Using Silicon Carbide MOSFET Inverter. In: Energy Optimal Switching Frequency for a 750V Metro Traction Drive Using Silicon Carbide MOSFET Inverter: . Paper presented at 10th International Conference on Applied Energy (ICAE2018), 22-25 August 2018, Hong Kong, China.
Open this publication in new window or tab >>Energy Optimal Switching Frequency for a 750V Metro Traction Drive Using Silicon Carbide MOSFET Inverter
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2018 (English)In: Energy Optimal Switching Frequency for a 750V Metro Traction Drive Using Silicon Carbide MOSFET Inverter, 2018Conference paper, Poster (with or without abstract) (Refereed)
Abstract [en]

The introduction of Silicon Carbide (SiC) MOSFET based inverters into the traction drive makes it possible to increase the inverter switching frequency and reduce energy consumption. This paper describes how to model switching frequency dependent losses in the traction drive and compares the calculated losses to measurements done on a newly developed SiC MOSFET based traction drive. The results from the developed loss models of motor and inverter agrees well with the results from energy measurements. This paper concludes that the energy use of the traction motor and inverter can be simulated well using simple models where skin-effect losses in the motor are modelled in detailed. This paper also concludes that in terms of energy efficiency, the optimal switching frequency using a SiC MOSFET based inverter, is in the range of 3-6 kHz.

National Category
Control Engineering
Identifiers
urn:nbn:se:mdh:diva-42582 (URN)
Conference
10th International Conference on Applied Energy (ICAE2018), 22-25 August 2018, Hong Kong, China
Available from: 2019-02-06 Created: 2019-02-06 Last updated: 2019-06-03Bibliographically approved
Rahman, M., Avelin, A., Kyprianidis, K., Jansson, J. & Dahlquist, E. (2018). Model based Control and Diagnostics strategies for a Continuous Pulp Digester. In: Paper Conference and Trade Show, PaperCon 2018: . Paper presented at TAPPI Paper Conference and Trade Show, PaperCon 2018; Charlotte; United States; 15 April 2018 through 18 April 2018; Code 143482 (pp. 136-147). , 1
Open this publication in new window or tab >>Model based Control and Diagnostics strategies for a Continuous Pulp Digester
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2018 (English)In: Paper Conference and Trade Show, PaperCon 2018, 2018, Vol. 1, p. 136-147Conference paper, Published paper (Refereed)
Abstract [en]

Kappa number, which essentially indicates the amount of lignin left in the pulp after cooking, is the most important physical quantity linked to the quality and economics of a Kraft-pulp mill. Controlling the Kappa number is a difficult task mainly due to the naturally varying feedstock, significant residence time, insufficient measurements and complex nature of the delignification process. Moreover, faults such as screen clogging, hang-ups and channeling in the process often occur and increase the operational costs considerably. In this work, the possibility of feedforwarding the lignin content of incoming wood chips, by a near-infrared spectroscopic measurement of one of the major process disturbances, to a model predictive controller, is investigated by means of modeling and simulation studies. Additionally, a simple Bayesian network based diagnostics approach is proposed to detect the continuous digester faults.

National Category
Engineering and Technology Energy Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-41297 (URN)2-s2.0-85060374344 (DOI)2-s2.0-85060374344 (Scopus ID)9781510871892 (ISBN)
Conference
TAPPI Paper Conference and Trade Show, PaperCon 2018; Charlotte; United States; 15 April 2018 through 18 April 2018; Code 143482
Projects
FUDIPO
Available from: 2018-11-07 Created: 2018-11-07 Last updated: 2019-10-01Bibliographically approved
Naqvi, M., Dahlquist, E., Yan, J., Naqvi, S. R., Nizami, A. S., Salman, C. A., . . . Qureshi, A. S. (2018). Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production. Applied Energy, 224, 636-646
Open this publication in new window or tab >>Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production
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2018 (English)In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 224, p. 636-646Article in journal (Refereed) Published
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.

Place, publisher, year, edition, pages
Elsevier Ltd, 2018
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-39297 (URN)10.1016/j.apenergy.2018.05.005 (DOI)000436901400049 ()2-s2.0-85046790342 (Scopus ID)
Available from: 2018-05-24 Created: 2018-05-24 Last updated: 2018-07-19Bibliographically approved
Ghaviha, N., Bohlin, M., Holmberg, C., Dahlquist, E., Skoglund, R. & Jonasson, D. (2017). A driver advisory system with dynamic losses for passenger electric multiple units. Transportation Research Part C: Emerging Technologies, 85, 111-130
Open this publication in new window or tab >>A driver advisory system with dynamic losses for passenger electric multiple units
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2017 (English)In: Transportation Research Part C: Emerging Technologies, ISSN 0968-090X, E-ISSN 1879-2359, Vol. 85, p. 111-130Article in journal (Refereed) Published
Abstract [en]

Driver advisory systems, instructing the driver how to control the train in an energy efficient manner, is one the main tools for minimizing energy consumption in the railway sector. There are many driver advisory systems already available in the market, together with significant literature on the mathematical formulation of the problem. However, much less is published on the development of such mathematical formulations, their implementation in real systems, and on the empirical data from their deployment. Moreover, nearly all the designed driver advisory systems are designed as an additional hardware to be added in drivers’ cabin. This paper discusses the design of a mathematical formulation and optimization approach for such a system, together with its implementation into an Android-based prototype, the results from on-board practical experiments, and experiences from the implementation. The system is based on a more realistic train model where energy calculations take into account dynamic losses in different components of the propulsion system, contrary to previous approaches. The experimental evaluation shows a significant increase in accuracy, as compared to a previous approach. Tests on a double-track section of the Mälaren line in Sweden demonstrates a significant potential for energy saving.

Place, publisher, year, edition, pages
Elsevier Ltd, 2017
Keywords
Driver advisory system, Electric multiple unit, Energy efficiency, Driver training, Electric losses, Electric railroads, Electric traction, Energy conservation, Energy utilization, Propulsion, Railroad transportation, Rapid transit, Advisory systems, Double-track section, Energy calculation, Experimental evaluation, Mathematical formulation, Minimizing energy, Optimization approach, control system, electric vehicle, energy use, optimization, railway transport, train, Sweden
National Category
Energy Engineering
Identifiers
urn:nbn:se:mdh:diva-37410 (URN)10.1016/j.trc.2017.09.010 (DOI)000423006600006 ()2-s2.0-85034098198 (Scopus ID)
Available from: 2017-12-07 Created: 2017-12-07 Last updated: 2018-10-06Bibliographically approved
Rahman, M., Avelin, A., Kyprianidis, K. & Dahlquist, E. (2017). An Approach For Feedforward Model Predictive Control For Pulp and Paper Applications: Challenges And The Way Forward. In: Paper Conference and Trade Show, PaperCon 2017: Renew, Rethink, Redefine the Future, Volume 3. Paper presented at PaperCon 2017, April 23 - 26, 2017 Minneapolis, Minnesota, USA (pp. 1441-1450). TAPPI Press, 10
Open this publication in new window or tab >>An Approach For Feedforward Model Predictive Control For Pulp and Paper Applications: Challenges And The Way Forward
2017 (English)In: Paper Conference and Trade Show, PaperCon 2017: Renew, Rethink, Redefine the Future, Volume 3, TAPPI Press, 2017, Vol. 10, p. 1441-1450Conference paper, Published paper (Refereed)
Abstract [en]

Due to the naturally varying feedstock, significant residence time, insufficient measurements and complex nature of the delignification process, producing pulp with consistent quality i.e. stable kappa number with sufficiently high yield is a challenging task that requires multi-variable process control. A wide variety of control structures, ranging from classical concepts like cascade control, feedforward, ratio control, and parallel control to more modern concepts like model-based predictive control, is used in pulp and paper industries all over the world. In this paper, a survey of model-based predictive control will be presented along with the control challenges that lie within the chemical pulping process. The potential of this control concept for overcoming the aforementioned technical challenges will also be discussed in the second part of the paper. Particular focus will be given on the use of near-infrared spectroscopy based soft-sensors coupled with dynamic process models as an enabler for feedforward model-based predictive control. Overall, the proposed control concept is expected to significantly improve process performance, in the presence of measurement noise and various complex chemical process uncertainties common in pulp and paper applications.

Place, publisher, year, edition, pages
TAPPI Press, 2017
Keywords
Pulp and paper, Pump Digester, MPC, Advanced control, Process modelling, NIR
National Category
Mechanical Engineering
Research subject
Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-35839 (URN)2-s2.0-85041499426 (Scopus ID)9781510847286 (ISBN)
Conference
PaperCon 2017, April 23 - 26, 2017 Minneapolis, Minnesota, USA
Projects
FUDIPO
Funder
EU, Horizon 2020
Available from: 2017-06-19 Created: 2017-06-19 Last updated: 2019-09-16Bibliographically approved
Skvaril, J., Kyprianidis, K. & Dahlquist, E. (2017). Applications of near-infrared spectroscopy (NIRS) in biomass energy conversion processes: A review. Applied spectroscopy reviews (Softcover ed.), 52(8), 675-728
Open this publication in new window or tab >>Applications of near-infrared spectroscopy (NIRS) in biomass energy conversion processes: A review
2017 (English)In: Applied spectroscopy reviews (Softcover ed.), ISSN 0570-4928, E-ISSN 1520-569X, Vol. 52, no 8, p. 675-728Article in journal (Refereed) Published
Abstract [en]

Biomass used in energy conversion processes is typically characterized by high variability, making its utilization challenging. Therefore, there is a need for a fast and non-destructive method to determine feedstock/product properties and directly monitor process reactors. The near-infrared spectroscopy (NIRS) technique together with advanced data analysis methods offers a possible solution. This review focuses on the introduction of the NIRS method and its recent applications to physical, thermochemical, biochemical and physiochemical biomass conversion processes represented mainly by pelleting, combustion, gasification, pyrolysis, as well as biogas, bioethanol, and biodiesel production. NIRS has been proven to be a reliable and inexpensive method with a great potential for use in process optimization, advanced control, or product quality assurance.

Keywords
Biodiesel, bioethanol, biogas, biomass, chemometrics, near-infrared spectroscopy, NIRS, near infrared, NIR, instrumentation
National Category
Analytical Chemistry Energy Systems Chemical Process Engineering Bioenergy Bioprocess Technology
Research subject
Biotechnology/Chemical Engineering; Energy- and Environmental Engineering
Identifiers
urn:nbn:se:mdh:diva-34992 (URN)10.1080/05704928.2017.1289471 (DOI)000412218800001 ()2-s2.0-85029956089 (Scopus ID)
Available from: 2017-03-03 Created: 2017-03-03 Last updated: 2018-07-25Bibliographically approved
Hellstrand, S. & Dahlquist, E. (2017). Biologic resources. In: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World: (pp. 93-156). Springer International Publishing
Open this publication in new window or tab >>Biologic resources
2017 (English)In: Natural Resources Available Today and in the Future: How to Perform Change Management for Achieving a Sustainable World, Springer International Publishing , 2017, p. 93-156Chapter in book (Other academic)
Place, publisher, year, edition, pages
Springer International Publishing, 2017
National Category
Economics and Business
Identifiers
urn:nbn:se:mdh:diva-37312 (URN)10.1007/978-3-319-54263-8_4 (DOI)2-s2.0-85033352259 (Scopus ID)9783319542638 (ISBN)9783319542614 (ISBN)
Available from: 2017-11-23 Created: 2017-11-23 Last updated: 2017-11-23Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-7233-6916

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