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  • 1.
    Andersson, Henny
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jansson, Joakim
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Suhonen, Anssi
    Savonia University of Applied Sciences.
    Jääskeläinen, Ari
    Savonia University of Applied Sciences.
    Reijonen, Tero
    Savonia University of Applied Sciences.
    Laatikainen, Reino
    University of Eastern Finland.
    Heitto, Anneli
    Finnoflag.
    Hakalehto, Elias
    Finnoflag.
    Technical Output Report – Pilot A in Sweden2014Report (Other academic)
  • 2. Andersson, Henny
    et al.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jansson, Joakim
    Mälardalen University, School of Business, Society and Engineering.
    Suhonen, Anssi
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Jääskeläinen, Ari
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Reijonen, Tero
    Laatikainen, Reino
    Heitto, Anneli
    Hakalehto, Elias
    TECHNICAL REPORT ON PILOT A TESTS IN SWEDEN2015Report (Refereed)
  • 3.
    Ericson, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology. KTH.
    A simplified model for anaerobic digestion of solid waste using real data from a full-scale biogas plant2010Conference paper (Refereed)
  • 4.
    Freidank, Tim
    et al.
    Ostfalia University of Applied Sciences, Germany.
    Drescher-Hartung, Silvia
    Ostfalia University of Applied Sciences, Germany.
    Behnsen, Andreas
    Ostfalia University of Applied Sciences, Germany.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Klintenberg, Patrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ahrens, Thorsten
    Ostfalia University of Applied Sciences, Germany.
    MIDTERM OUTPUT REPORT – PILOT B IN SWEDEN2014Report (Other academic)
  • 5.
    Guziana, Bozena
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Belous, Olga
    Klaipeda University.
    den Boer, Emilia
    Institute of Environment Protection Engineering, Wrocław University of Technology.
    MANUAL FOR SORTING OF WASTE FOR WASTE-TO-ENERGY SYSTEMS2011Report (Other (popular science, discussion, etc.))
  • 6.
    Hakalehto, E.
    et al.
    University of Helsinki, Helsinki, Finland.
    Heitto, A.
    University of Helsinki, Helsinki, Finland.
    Andersson, Henny
    Mälardalen University, School of Business, Society and Engineering.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jansson, Joakim
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Reijonen, T.
    Savonia University of Applied Sciences, Kuopio, Finland.
    Suhonen, A.
    Savonia University of Applied Sciences, Kuopio, Finland.
    Jääskeläinen, A.
    Savonia University of Applied Sciences, Kuopio, Finland.
    Laatikainen, R.
    University of Eastern Finland, Kuopio, Finland.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Klintenberg, Patrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Some remarks on processing of slaughterhouse wastes from ecological chicken abattoir and farm2016In: Microbiological Industrial Hygiene, Nova Science Publishers, Inc. , 2016, p. 271-293Chapter in book (Other academic)
    Abstract [en]

    In the meat industries, it is always of high importance to follow up the zoonotic and other hazardous micro-organisms, and to prevent their risky distribution, emission and dissemination. Besides proper hygiene control, as well as organized exploitation of the side streams and slaughterhouse wastes helps in the hygienization of the biomasses, processes, and the entire industry. During this experimentation it turned out that it was possible to produce gases and chemical goods, not only from the carboxylates, but also from the more tedious protein and lipid containing wastes. Moreover, these promising results were obtained from a substrate mix with manure and wood chips. These results implied to the high versatility and flexibility of the bioprocess during Pilot A tests within the European Union Baltic Sea region project ABOWE. In Sweden these tests were carried out using the combined wastes from the ecological chicken farm and abattoir as the raw materials. This is a report of the practical set up during intensive experimentation conducted jointly by the Swedish and Finnish personnel. The report of the runs in Sweden is presented also in the public report of the European Union funded project (www.abowe.eu).

  • 7.
    Klintenberg, Patrik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Eskelinen, Tuomo
    Huopana, Tuomas
    Jääskeläinen, Ari
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    INVESTMENT MEMO ABOWE PILOT B SWEDEN2014Report (Refereed)
    Abstract [en]

    This report is one output of ABOWE project (Implementing Advanced Concepts for Biological Utilization of Waste), which belongs to EU Baltic Sea Region Programme 2007-2013. ABOWE works with two promising technologies to unlock investments. Two mobile pilot plants have been built and will be tested in several Baltic Sea regions. These pilots are based on a novel biorefinery concept from Finnoflag Oy, Finland, known as Pilot A as well as a German dry fermentation process, known as Pilot B. The pilots form the basis for compilation of Investment Memos and organizing Investor Events. Also a regional model is used to evaluate the new processes’ economic and climatic impacts in each region. The desired outcome from ABOWE is implementer/investor driven continuation projects targeting full-scaleplant investments of the two technologies.

    The purpose of ABOWE Work Package 2 is to gather and communicate information from many aspects of technologies which are piloted with Pilot A and Pilot B to support investment decisions for full scale plants. In practice, a demo full scaleplant would be needed in order to convince the commercial investors and implementers to full scale plants. This means that ABOWE provides with profound information and a step forward regarding the two technologies. After ABOWE, the technology will need development for full-scale, and the feasibility will need further analysis. An implementer and investor should be found to conduct development further towards full-scale demo plant.

  • 8.
    Klintenberg, Patrik
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Eskelinen, Tuomo
    Lappi, Mervi
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Kauppinen, Marja
    Huopana, Tuomas
    Jääskeläinen, Ari
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Hakalehto, Elias
    INVESTMENT MEMO ABOWE PILOT A SWEDEN2015Report (Refereed)
    Abstract [en]

    This report was compiled by the ABOWE project (Implementing Advanced Concepts for Biological Utilization of Waste) funded by the EU Baltic Sea Region Programme 2007-2013. This report presentsresults and information of relevance for the up-scaling of the Finnoflag biorefinery technology, piloted in Finland, Poland and Sweden, to support investment decisions towards full-scale implementation.

    The piloting of the technology done by the ABOWE project provides valuable information and a step forward regarding the technology. The next step, after the pilot phase, would be to construct a full-scalede monstration plant to showcase the potential of the technology to potential commercial investorsor implementers. The bioprocess will need to be further designedand optimized through longer testing with selected waste materials to produce targeted products. This will all0w for full-scaleoperationsand further feasibility analysis. This falls beyond the scope of the ABOWE project. This report forms the basis of an investment memo that provides decision support topossible implementers and investors that are interested in taking the lead in the development of the technology further to a full-scale demo plant.

  • 9.
    Li, Hailong
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Nordlander, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    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.
    Zhao, Li
    Tianjin University, China.
    Using the solid digestate from a wet anaerobic digestion process as an energy resource2013In: Energy technology, ISSN 2194-4296, Vol. 1, no 1, p. 94-101Article in journal (Refereed)
    Abstract [en]

    The wet anaerobic digestion process is a widely used method to produce biogas from biomass. To avoid the risks involved with using the digestion waste as a fertilizer, this work investigates the possibilities to use the solid digestate as an energy resource to produce heat and electricity, which could save some energy currently consumed by the plant and, therefore, may increase the overall efficiency of a biogas plant. Simulations were conducted based on real data from the Växtkraft biogas plant in Västerås, Sweden as a case study. Results show that it is necessary to dry the solid digestate before combustion and include flue-gas condensation to recover enough heat for the drying process. When a steam turbine cycle is integrated, the generated electricity could cover 13–18 % of the total electricity consumption of the plant, depending on the degree of dryness. In addition, reducing the digestion period can increase the carbon content (ultimate analysis), the heating value, and the mass flow of the solid digestate. As a result, the production of electricity and heat is augmented in the steam turbine cycle. However, the production of biogas is reduced. Therefore, a comprehensive economic evaluation is suggested to optimize a biogas plant that uses the solid digestate from a wet anaerobic digestion process as an energy resource.

  • 10.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering. Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Developing the anaerobic digestion process through technology integration2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Process optimization is needed for the development and expansion of the biogas industry and to meet the ever growing demand for methane. This thesis explores process technologies for the development of the anaerobic digestion process and includes pre-treatments, studies on the effects of different mixing modes and evaluation of a water treatment technology.

    Two pre-treatments were evaluated, mechanical and electroporation, for treatment of ley crop silage. Mechanical treatment included two milling machines designed for recycling of paper, Grubben deflaker and Krima disperser, and showed an increased biogas production of 59 % and 43 % respectively as well as a positive energy balance and economic results.. Electroporation increased the biogas production with 16 %, however, development is needed to increase its energy efficiency.

    Digester mixing has an effect on the digestion result. The performed review and experiments show that the mixing demand increases with organic loading. Excessive mixing during process start up, instabilities and shock loads leads to increased volatile fatty acid concentrations and process inhibition. Reduction of mixing reduces the effects of process instabilities and periodical mixing with mixing breaks has been shown to be beneficial for biogas production.

    A high temperature membrane filtration unit was evaluated at 70 °C, 90 °C and 110 °C to determine separation efficiencies, permeation speed when treating process water at a biogas plant.  Improved separation can increase the capacity of the substrate pre-processing and reduce process related problems. The results show a total solids separation of 60 %, and an increasing filtration speed with temperature with fluxes of between 113 and 464 L/ h m2. The substrate pre-processing could theoretically handle up to 29 % more substrate as a result.

    Integration of these technologies in a biogas plant show that the pre-treatments studied exhibits a good performance when integrated and that mixing reduction has the potential to lower the process electricity demand by 23 % in the performed case study. However, even though the membrane filtration unit shows promising results it would demand a relatively high energy consumption and lead to limited benefits to a process already at it maximum organic loading.

  • 11.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    The wet fermentation biogas process: Limitations and possibilities for efficiency improvements2010Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    The biogas process is known as an environmental friendly and sustainable way of producing energy and fuel but to be fully commercially competitive with other types of processes, efficiency improvements are needed. By doing a case study at the Växtkraft biogas plant in Västerås, Sweden, three specific limitations were identified and studied. Firstly, to improve the capacity of the plant, pre-treatments of the different substrates are needed to disintegrate the substrate and by doing so increasing the gas yield and the speed in which it is produced. Secondly, to improve the fermentation process itself more knowledge is needed around the mixing inside the digester. To be able to create an optimal and stable environment for the microorganisms the mixing is the key, because the mixing affects the mass transfer of all solids, nutrients, gases and other substances in the digester. Thirdly, the water treatment of the recirculated process water cannot reach the desired separation of dry matter (DM) and this is affecting the capacity of the plant negatively. The feed for the digester is produced by mixing the process water and the substrate to get a pumpable slurry with a DM content of 8-10 %. When there is too much DM in the process water to begin with, the mixing ratio between the substrate and the liquid changes, decreasing the amount of substrate that can be added to the mixture and later on fed to the digester.

     

    The full biogas potential of most organic materials cannot be extracted during the relatively short retention time of most digesters because of their complex structures. The organic materials are broken down too slowly and the nutrients cannot become biologically available in that time span. This means that a lot of the bound energy in the organic material leaves the biogas plant with the liquid digestate. The efficiency of the process can be improved by pre-treating the material before digestion. Pre-treatment experiments to disintegrate ley crop silage using electroporation, a treatment using electrical fields, were conducted to study its effect on the biogas yield. The experiments resulted in up to twice the amount of biogas being produced from the pre-treated material compared to untreated material.

     

    Numerical simulations of the mixing inside a digester were carried out to understand the effect that a gas lift mixing configuration has on the mass transfer in the system. The mixing dynamics were evaluated by testing five different flow rates of the injected gas and the effect that the liquid recirculation system has. The results indicate that there are large unmixed zones and that changing the gas flow rate only has a marginal effect on these areas. The simulation also suggests that the outlet of the liquid recirculation system is situated too close to the gas injectors, resulting in energy losses in form of diminished mixing of the digester.

     

    Experiments to reduce the DM content of the recirculated process water were carried out using a ceramic ultrafiltration membrane. The flux through the membrane and the separation efficiency were investigated at different operation temperatures, 70°C, 90°C and 110°C. The results show that 59-63 % of the DM was separated in this temperature interval and that the flux/flow through the membrane increased with the temperature. These results correspond to a 29 % increase in the capacity to add new substrate. The energy required to heat the membrane, if heat recovery is used, is small in comparison to the increased methane yield.

     

    In the best case scenario these above identified improvements could increase the methane yield by up to 40%.

  • 12.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Bel Fdhila, Rebei
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    ON MODELLING THE MIXING IN A DIGESTER FOR BIOGAS PRODUCTION2009In: / [ed] I. Troch, F. Breitenecker, 2009Conference paper (Other academic)
    Abstract [en]

    At the Vaxtkraft biogas plant the mixing is produced by pumping in biogas and releasing it at the bottom. The mixing inside the digester of a biogas plant is important for good biogas production and since it is complicated to study the mixing inside the digester while it is in operation, this study is based on numerical simulations using a computational fluid dynamic finite volume code. To study the mixing dynamics, five different flow rates of gas (air) injections ranging from 0.1 to 0.6kg/s were simulated. These gas flow rates produced an average liquid speed in the digester between 0.10 and 0.22 m/s. The liquid recirculation impact on the mixing was investigated through the simulation of a case where it is combined with the lowest gas injection flow rate. The results from the simulation suggest that the liquid outlet is situated too close to the gas injection, resulting in energy losses in form of diminished mixing of the digester. A complete redesign of the digester is needed to seriously overcome the mixing limitation.

  • 13.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Eriksson, Per
    Mälardalen University, School of Business, Society and Engineering.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    The effects of different mixing intensities during anaerobic digestion of the organic fraction of municipal solid waste2014In: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 34, no 8, p. 1391-1397Article in journal (Refereed)
    Abstract [en]

    Mixing inside an anaerobic digester is often continuous and is not actively controlled. The selected mixing regime can however affect both gas production and the energy efficiency of the biogas plant. This study aims to evaluate these effects and compare three different mixing regimes, 150 RPM and 25 RPM continuous mixing and minimally intermittent mixing for both digestion of fresh substrate and post-digestion of the organic fraction of municipal solid waste. The results show that a lower mixing intensity leads to a higher biogas production rate and higher total biogas production in both cases. 25 RPM continuous mixing and minimally intermittent mixing resulted in similar biogas production after process stabilization, while 150 RPM continuous mixing resulted in lower production throughout the experiment. The lower gas production at 150 RPM could not be explained by the inhibition of volatile fatty acids. Cumulative biogas production until day 31 was 295. ±. 2.9, 317. ±. 1.9 and 304. ±. 2.8. N. ml/g VS added during digestion of fresh feed and 113. ±. 1.3, 134. ±. 1.1 and 130. ±. 2.3. N. ml/g VS added during post digestion for the 150 RPM, 25 RPM and minimally mixed intensities respectively. As well as increasing gas production, optimal mixing can improve the energy efficiency of the anaerobic digestion process.

  • 14.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lagerkvist, Anders
    Luleå University of Technology, Division of Waste Science and Technology.
    Nilsson, Erik
    Andreas, Lale
    Luleå University of Technology, Division of Waste Science and Technology.
    Carlsson, My
    Luleå University of Technology, Division of Waste Science and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Pre-treatment of Substrate for Increased Biogas ProductionManuscript (preprint) (Other academic)
    Abstract [en]

    The full biogas potential of most organic material cannot be exploited with today’s technology. The complex structures of the organic materials are broken down too slowly and the nutrients cannot become biologically available during the relatively short retention time of most digesters. This means that a lot of the bound energy in the organic material leaves the biogas plant with the liquid digestate. There is a possibility to increase the efficiency of the process by pre-treating the material before digestion. This paper explores a pre-treatment of ley crop silage using electrical fields, known as electroporation (EP). Different settings of the EP equipment were tested and the results were analysed using a batch digestion setup. The results from the experiments show that there is a possibility to double the biogas production at typical retention times of a CSTR. The energy balance of the EP equipment suggests that the pre-treatment yield is around 2-6 times larger than the energy input to the process, i.e. energy in the form of methane.  

  • 15.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lagerkvist, Anders
    Division of Waste Science and Technology, Luleå University of Technology, Luleå, Sweden.
    Nilsson, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Carlsson, My
    AnoxKaldnes AB, Lund, Sweden.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Evaluating the effects of electroporation pre-treatment on the biogas yield from ley crop silage.2014In: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 174, no 7, p. 2616-2625Article in journal (Refereed)
    Abstract [en]

    Exploiting the full biogas potential of some types of biomass is challenging. The complex structures of lignocellulosic biomass are difficult to break down and thus require longer retention times for the nutrients to become biologically available. It is possible to increase the digestibility of the substrate by pre-treating the material before digestion. This paper explores a pre-treatment of ley crop silage that uses electrical fields, known as electroporation (EP). Different settings of the EP equipment were tested, and the results were analyzed using a batch digestion setup. The results show that it is possible to increase the biogas yield with 16 % by subjecting the substrates to 65 pulses at a field strength of 96 kV/cm corresponding to a total energy input of 259 Wh/kg volatile solid (VS). However, at 100 pulses, a lower field strength of 48 kV/cm and the same total energy input, no effects of the treatment were observed. The energy balance of the EP treatment suggests that the yield, in the form of methane, can be up to double the electrical energy input of the process.

  • 16.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Leksell, Niklas
    Växtkraft.
    Schnürer, Anna
    SLU.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Effects of mechanical pre-treatment on the biogas yield from ley crop silage2012In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 97, p. 498-502Article in journal (Refereed)
    Abstract [en]

    Previous studies on substrates for biogas production have shown that different types of pre-treatments make the material more accessible for microbial degradation by breaking down the complex structure of the organic material, thereby increasing their potential for gas production. In this paper, two different mechanical pre-treatment apparatus, i.e. a Grubben deflaker (Gd) and a Krima disperser (Kd), were tested in a full scale setup to evaluate their effects on ley crop silage. The treatments were investigated with regard to their effects on particle size, methane potential, capacity and energy balance. The results after 115 days of incubation in a batch assay show that methane production increased by 59% and 43% respectively after grinding with Gd and Kd. In both treatments, 90% of the ley crop was ground to particles of less than 2 mm and more than 50% of the sample was reduced to particles smaller than 0.125 mm. The energy balance was positive for Gd and around the break-even point for Kd. Analysis of the setup showed that Kd had almost twice the capacity of the Gd. If installed in the co-digestion biogas plant Vaxtkraft in Vasteras, Sweden, the Gd and Kd could increase annual biogas yields by 790 MW h and 585 MW h respectively. (c) 2012 Elsevier Ltd. All rights reserved.

  • 17.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Business, Society and Engineering.
    Nilsson, Erik
    Lagerkvist, Anders
    Luleå University of Technology, Division of Waste Science and Technology.
    Andreas, Lale
    Luleå University of Technology, Division of Waste Science and Technology.
    Carlsson, My
    Luleå University of Technology, Division of Waste Science and Technology.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering.
    Pretreatment of Substrate for Increased Biogas Production2010Conference paper (Refereed)
  • 18.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Bel Fdhila, Rebei
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center. ABB AB, Corporate Research, Västerås.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Effects of mixing on the result of anaerobic digestion: Review2014In: Renewable & Sustainable Energy Reviews, ISSN 1364-0321, Vol. 40, p. 1030-1047Article in journal (Refereed)
    Abstract [en]

    Mixing in an anaerobic digester keeps the solids in suspension and homogenizes the incoming feed with the active microbial community of the digester content. Experimental investigations have shown that the mixing mode and mixing intensity have direct effects on the biogas yield even though there are conflicting views on mixing design. This review analyzes and presents different methods to evaluate the mixing in a digester (chemical and radioactive tracers and laboratory analysis), tools for digester design (computational fluid dynamics and kinetic modeling) and current research on the effects of mixing on the anaerobic digestion process. Empirical data on experiments comparing different mixing regimes have been reviewed from both a technical and microbial standpoint with a focus both on full scale digesters and in lab-scale evaluations. Lower mixing intensity or uneven mixing in the anaerobic digestion process can be beneficial during the startup phase to allow for methanogenic biomass growth and alleviate process instability problems. Intermittent mixing has been shown to be able to yield a similar gas production as continuous mixing but with the possibility to reduce the maintenance and energy demands of the process. Problems often experienced with experimental design include the effect of mixing on the solids retention time, and measurement of steady state gas production because of startup instabilities. Further research should be aimed at studying the effects of mixing on a chemical and microbial level and on the different stages of anaerobic digestion (hydrolysis, acidogenesis, acetogenesis and methanogenesis). The focus should be on the effects of mixing on a multiple stage digestion process and also finding new methods to evaluate the effects of mixing in the one stage digestion process rather than evaluating a wider range of mixing modes, intensities and substrates.

  • 19.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Bel Fdhila, Rebei
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    PROBLEMS AND POSSIBILITIES WITH THE IMPLEMENTATION OF SIMULATION AND MODELING AT A BIOGAS PLANT2012Conference paper (Refereed)
    Abstract [en]

    Advanced models are being developed for the anaerobicdigestion (AD) process. These models can be used to control and optimize industrial size biogas plant to reach their full potential. There are many models available for different types of implementations. However, many of the published models demands extensive chemical analysis that might not be practically and economically viable in industry. Sampling routines at six Swedish biogas plants was compiled for comparison with the demand of input in published modeling approaches. The gap between the models and practices in industry has to come together through model simplification and extended sampling routines. Chemical oxygen demand (COD) for example is not a commonly used analysis in Swedish biogas plants but which is regularly used to model the AD. Knowledge of the biochemical processes in AD built in to a model can help operators increase the biogas yield of the plant without jeopardizing the production. There is a lack of robust online measurement equipment today to be able to have reliable online models for operational support but near infrared spectroscopy (NIR) is a promising technology for online measuring of a series of different characteristics that could make modeling more interesting for the AD industry. The mixing has as of yet not been devoted much attention to when modeling the process.

  • 20.
    Lindmark, Johan
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Kastensson, Jan
    Mercatus Engn AB.
    Pettersson, Carl-magnus
    Svensk Växtkraft AB.
    Membrane filtration of process water at elevated temperatures: a way to increase the capacity of a biogas plant2011In: Desalination, ISSN 0011-9164, E-ISSN 1873-4464, Vol. 267, no 2-3, p. 160-169Article in journal (Refereed)
    Abstract [en]

     Waste water from a biogas process is often recirculated and mixed with the incoming organic material to produce a feed for the digester. The dry matter (DM) content of the final mixture should be as high as possible to maximise the capacity of the plant without exceeding the capability of the pumps. This means that the DM content of the recirculated process water has a large impact on the amount of substrate that can be processed. Experiments to reduce the dry matter content of the recirculated process water were carried out using a ceramic ultrafiltration (UF) membrane. The influence on the flux through the membrane and the separation efficiency at different operation temperatures, 70°C, 90°C and 110°C, were investigated. Higher temperatures resulted in increased flux/flow through the membrane. The DM content was reduced from 4% to 1.6%, corresponding to a 29 % increase of new material that could be added to the process. The energy required to heat the membrane when using heat recovery is small compared to the energy of the methane produced from the additional added substrate. The lifespan of the membranes and uncertainties in the substrate DM content are showed to be important for the economic result.

  • 21.
    Odlare, Monica
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Abubaker, Jamal
    SLU.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Pell, Mikael
    SLU.
    Thorin, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Nehrenheim, Emma
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Emissions of N2O and CH4 from agricultural soils amended with two types of biogas residues2012In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 44, p. 112-116Article in journal (Refereed)
    Abstract [en]

    Biogas residues contain valuable plant nutrients, important to the crops and also to soil microorganisms. However, application of these materials to the soils may contribute to the emission of greenhouse gases (GHG) causing global warming and climate change. In the present study, incubation experiment was carried out, where the emission rates of N2O and CH4 were measured after amending two soils with two types of biogas residues: (1) a regular residue from a large scale biogas plant (BR) and (2) a residue from an ultrafiltration membrane unit connected to a pilot-scale biogas plant (BRMF). The emissions of N2O and CH4 were measured at two occasions: at 24 h and at 7 days after residue amendment, respectively. Amendment with filtered biogas residues (BRMF) led to an increase in N2O emissions with about 6-23 times in organic and clay soil, respectively, in comparison to unfiltered biogas residues (BR). Methane emission was detected in small amounts when filtered biogas residue was added to the soil. Amendment of unfiltered biogas to the organic soil resulted in net consumption. In conclusion, fertilization with BRMF can be combined with risk of an increase N2O emission, especially when applied to organic soils. However, in order to transfer these results to real life agriculture, large scale field studies need to be carried out

  • 22.
    Odlare, Monica
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ericsson, Anders
    Brunnby Farm, HS Konsult, Västerås, Sweden.
    Pell, Mikael
    Swedish Univ Agr Sc, Uppsala, Sweden.
    Use of organic wastes in agriculture2015In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, p. 2472-2476Article in journal (Refereed)
    Abstract [en]

    As the number of biogas plants and wastewater treatment plants continues to grow, there is an urgent need to find sustainable usage of the organic wastes produced in these facilities Recycling of organic wastes within agriculture can reduce the need for mineral fertilizer and restore organic carbon deficiency in the soil. The results from a 16-year long field experiment, where agricultural lands have been amended using sewage sludge and biogas residue is presented in this paper. Plant nutrients, organic contaminants and metals have been analyzed in order to evaluate the impact of the wastes on soil and crop quality. The results show that only small differences in plant uptake of metals and organic pollutants appear after 16 years. In addition, biogas residues performed well as a fertilizers, although not as well as mineral fertilizers.

  • 23.
    Schwede, Sebastian
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Thorin, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Klintenberg, Patrik
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jääskelainen, A
    Savonia Univ Appl Sci, Environm Engn, Kuopio, Finland.
    Suhonen, A.
    Savonia Univ Appl Sci, Environm Engn, Kuopio, Finland.
    Laatikainen, R.
    Univ Eastern Finland, Sch Pharm, Kuopio, Finland.
    Hakalehto, E.
    Univ Eastern Finland, Sch Pharm, Kuopio, Finland.
    Using slaughterhouse waste in a biochemical-based biorefinery – results from pilot scale tests2017In: Environmental technology, ISSN 0959-3330, E-ISSN 1479-487X, p. 1275-1284Article in journal (Refereed)
    Abstract [en]

    A novel biorefinery concept was piloted using protein-rich slaughterhouse waste, chicken manureand straw as feedstocks. The basic idea was to provide a proof of concept for the production ofplatform chemicals and biofuels from organic waste materials at non-septic conditions. Thedesired biochemical routes were 2,3-butanediol and acetone–butanol fermentation. The resultsshowed that hydrolysis resulted only in low amounts of easily degradable carbohydrates.However, amino acids released from the protein-rich slaughterhouse waste were utilized andfermented by the bacteria in the process. Product formation was directed towards acidogeniccompounds rather than solventogenic products due to increasing pH-value affected by ammoniarelease during amino acid fermentation. Hence, the process was not effective for 2,3-butanediolproduction, whereas butyrate, propionate,γ-aminobutyrate and valerate were predominantlyproduced. This offered fast means for converting tedious protein-rich waste mixtures intoutilizable chemical goods. Furthermore, the residual liquid from the bioreactor showedsignificantly higher biogas production potential than the corresponding substrates. Thecombination of the biorefinery approach to produce chemicals and biofuels with anaerobicdigestion of the residues to recover energy in form of methane and nutrients that can beutilized for animal feed production could be a feasible concept for organic waste utilization.

  • 24.
    Thorin, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Daianova, Lilia
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Nordlander, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Song, Han
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Jääskeläinen, Ari
    The Municipal Federation of Savonia University of Applied Sciences.
    Malo, Laura
    Centre for Economic Development, Transport and the Environment for North Savo (CNS).
    den Boer, Emilia
    Institute of Environment Protection Engineering, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
    den Boer, Jan
    WAMECO S.C., ul. Malinowa 7, 55-002 Kamieniec Wrocławski, Poland.
    Szpadt, Ryszard
    Institute of Environment Protection Engineering, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
    Belous, Olga
    Klaipeda University (KLU).
    Kaus, Taivo
    Estonian Regional and Local Development Agency (ERKAS).
    Käger, Marja
    Estonian Regional and Local Development Agency (ERKAS).
    State of the art In the Waste to Energy Area: Technology and Systems2011Report (Other academic)
  • 25.
    Thorin, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Kastensson, Jan
    Pettersson, Carl-Magnus
    Persson, Per-Erik
    PERFOMANCE OPTIMIZATION OF THE VÄXTKRAFT BIOGAS PRODUCTION PLANT –THE USE OF MEMBRANE FILTRATION2009In: Proceedings of ICAE'09, 2009, p. 594-602Conference paper (Refereed)
    Abstract [en]

    Today we can see a large potential for biogas production from any kind of organic residue as well as from different crops, farm land residues or graze. However, the technology for biogas production is not optimized and thus not fully cost-effective. To be fully commercially competitive with other types of fuels, efficiency improvements of the process are needed. In the research project BioGasOpt, performed in cooperation between Mälardalen University and industry, performance optimization of the Växtkraft biogas production plant and surrounding systems are studied.  In this paper the project will be presented and the possibility for improvements by using membrane filtration to reduce the dry matter in the recirculated water is addressed.

    In the Växtkraft biogas plant, in Västerås, Sweden, organic wastes from households and restaurants are mixed and fermented with crops from graze land. A lot of water is used in the process and the surplus is filtered off in decanter centrifuges. The decantate from the centrifuges is partly recirculated in the process and the problem is that the content of dry matter in the decantate is increasing and is today around 4 %.  In this paper the potential to use membrane filtration to improve the performance of biogas plants is studied. The consequences concerning production capacity, energy use, and operation of the plant are discussed. The first results from tests on using ceramic membrane filters at the Växtkraft biogas plant show that it possible to decrease the content of dry matter in the process water to 2 % at operation temperatures around 100˚C.   

  • 26.
    Thorin, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Nordlander, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Odlare, Monica
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Kastensson, Jan
    Mercatus Engineering AB.
    Leksell, Niklas
    Svensk Växtkraft AB.
    Pettersson, Carl-Magnus
    Svensk Växtkraft AB.
    Performance Optimization of the Växtkraft Biogas Production Plant2011In: ICAE2011 - International Conference on Applied Energy, 2011, p. 1833-1844Conference paper (Refereed)
    Abstract [en]

    All over the world there is a strong interest and also potential for biogas production fromorganic residues as well as from different crops. However, to be commercially competitive withother types of fuels, efficiency improvements of the biogas production process are needed. In this paper the results of the project BioGasOpt, Performance optimization of the Växtkraft biogas production plant and surrounding system, are summarized. The project is performed in cooperation between Mälardalen University, the biogas plant Svensk Växtkraft AB, the membrane filtration company Mercatus Engineering AB and the farm Nibble Lantbruk AB.

    In the Växtkraft biogas plant organic wastes from households and restaurants are mixed and digested with crops from graze land. Four areas of importance for the performance of the plant are addressed in the BioGasOpt project: treatment of the feed material to enhance the fermentation rate, transport performance of gas and nutrients in the reactor, limitation of the ballast of organics in the water stream recirculated in the process, and use of the biogas plant residues at farms.

    The results indicate a potential to increase the biogas yield from the process with up to 40 % with pre-treatment of the feed and including membrane filtration in the process. The possibilities to improve the mixing in the digester also show a significant potential for even higher biogas yields. Modelling of the biogas process for better process control is also identified as a possible way to further improve the biogas yield. However, model development taking into account what input data is possible to get at a biogas plant in operation is needed.

    Further, the results from the project show that the residues from biogas production can be used as fertilizers but that the emission of N2O from the fertilised soil is dependent on the soil type and spreading technology.

  • 27.
    Thorin, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Nordlander, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Odlare, Monica
    Mälardalen University, School of Business, Society and Engineering.
    Dahlquist, Erik
    Mälardalen University, School of Business, Society and Engineering.
    Kastensson, Jan
    Mercatus Engineering AB.
    Leksell, Niklas
    Svensk Växtkraft AB.
    Pettersson, Carl-Magnus
    Svensk Växtkraft AB.
    Performance optimization of the Växtkraft biogas production plant2012In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 97, p. 503-508Article in journal (Refereed)
    Abstract [en]

    All over the world there is a strong interest and also potential for biogas production from organic residues as well as from different crops. However, to be commercially competitive with other types of fuels, efficiency improvements of the biogas production process are needed. In this paper, results of improvements studies done on a full scale co-digestion plant are presented

     

    In the plant organic wastes from households and restaurants are mixed and digested with crops from graze land. The areas for improvements of the plant addressed are treatment of the feed material to enhance the digestion rate, limitation of the ballast of organics in the water stream recirculated in the process, and use of the biogas plant residues at farms. Results from previous studies on pre-treatment and membrane filtration of recirculated process water are combined for estimation of the total improvement potential. Further, the possibility to use neural networks to predict biogas production using historical data from the full-scale biogas plant was investigated. Results from investigation of using the process residues as fertilizer are also presented.

     

    The results indicates a potential to increase the biogas yield from the process with up to over  30 % with pre-treatment of the feed and including membrane filtration in the process. Neural networks have the potential to be used for prediction of biogas production. Further, it is shown that the residues from biogas production can be used as fertilizers but that the emission of N2O from the fertilised soil is dependent on the soil type and spreading technology.

  • 28.
    Thorin, Eva
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Freidank, Tim
    Ostfalia University of Applied Sciences.
    Drescher-Hartung, Silvia
    Ostfalia University of Applied Sciences.
    Daukšys, Vygintas
    Klaipeda University.
    Ahrens, Thorsten
    Ostfalia University of Applied Sciences.
    POSSIBILITES FOR OPTIMIZATION OF THE DRY DIGESTION PROCESS2014Report (Other academic)
  • 29.
    Thorin, Eva
    et al.
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Nordlander, Eva
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Lindmark, Johan
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Dahlquist, Erik
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Yan, Jinyue
    Mälardalen University, School of Sustainable Development of Society and Technology.
    Bel Fdhila, Rebei
    Mälardalen University, School of Sustainable Development of Society and Technology.
    MODELING OF THE BIOGAS PRODUCTION PROCESS- A REVIEW2012Conference paper (Refereed)
    Abstract [en]

    Production of biogas by digestion of organic wastes and other feedstock is one of the important technical solutions that contribute to the transform of the energy system from being fossil fuel dependent to renewable energy originated. To be fully commercial and competitive, the production of biogas needs to be further developed and optimized based on the technical, economic and environmental aspects. Thus, comprehensive understanding of fluid dynamics and microbial reactions in the digestion process is necessary to accurately and robustly model, predict and control the biogas production.

    In this paper possible pathways for modeling the biogas reactor is discussed based on previous work on anaerobic digestion modeling and modeling of the fluid flow in reactors. Important parameters for modeling biogas production, with a focus on processes using waste as feedstock, are considered. Identification of knowledge gaps for the modeling of the biogas process is performed and how to overcome the obstacles is addressed.

  • 30.
    Thorin, Eva
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Nordlander, Eva
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Jansson, Joakim
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Hakalehto, Elias
    Finnoflag.
    Heitto, Anneli
    Finnoflag.
    Jääskeläinen, Ari
    Savonia University of Applied Sciences.
    Suhonen,, Anssi
    Savonia University of Applied Sciences.
    Den Boer, Emilia
    Wrocław University of Technology.
    Possibilites for Optimization of Biorefinery process2014Report (Other academic)
  • 31.
    Thorin, Eva
    et al.
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Schwede, Sebastian
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Lindmark, Johan
    Mälardalen University, School of Business, Society and Engineering, Future Energy Center.
    Ahrens, Torsten
    Ostfalia University of Applied Science, Wolfenbüttel, Germany.
    DRY DIGESTION PILOT TESTS USING RESIDUAL MUNICIPAL WASTE AS SUBSTRATE2015In: Sardinia 2015 / [ed] Raffaello Cossu et al, Padova: CISA publisher , 2015Conference paper (Refereed)
    Abstract [en]

    A pilot plug-flow dry digestion process was tested for production of biogas from the fine fraction of the residual municipal solid waste after source sorting of the organic fraction of the waste. The residual waste is complex, containing a mix of hard and soft plastic, paper, metal, glass, and a varying amount of organic material. The utilization as a substrate for biogas production is therefore challenging. The purpose of the pilot tests was to determine if it is technically feasible to produce biogas from this waste. The plant was operated under thermophilic conditions for almost three months. In parallel also a garage fermentation batch pilot plant was tested with the same substrate. The results from the tests are promising concerning the biogas production even if there are indications that the process in the plug-flow reactor was operated in so called inhibited steady state at the higher loading rates.

1 - 31 of 31
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