Change search
Link to record
Permanent link

Direct link
BETA
Aslanzadeh, Solmaz
Alternative names
Publications (10 of 16) Show all publications
Aslanzadeh, S., Rajendran, K. & Taherzadeh, M. (2014). A comparative study between single- and two-stage anaerobic digestion processes: Effects of organic loading rate and hydraulic retention time. International Biodeterioration & Biodegradation, 95, 181-188
Open this publication in new window or tab >>A comparative study between single- and two-stage anaerobic digestion processes: Effects of organic loading rate and hydraulic retention time
2014 (English)In: International Biodeterioration & Biodegradation, ISSN 0964-8305, E-ISSN 1879-0208, Vol. 95, p. 181-188Article in journal (Refereed) Published
Abstract [en]

The effect of an organic loading rate (OLR) and a hydraulic retention time (HRT) was evaluated by comparing the single-stage and two-stage anaerobic digestion processes. Wastes from the food processing industry (FPW) and the organic fraction of the municipal solid waste (OFMSW) were used as substrates. The OLR was increased at each step from 2 gVS/l/d to 14 gVS/l/d, and the HRT was decreased from 10 days to 3 days. The highest theoretical methane yield achieved in the single-stage process was about 84% for the FPW during an OLR of 3 gVS/l/d at a HRT of 7 days and 67% for the OFMSW at an OLR of 2 gVS/l/d and a HRT of 10 days. The single-stage process could not handle a further increase in the OLR and a decrease in the HRT; thus, the process was stopped. A more stable operation was observed at higher OLRs and lower HRTs in the two-stage system. The OLR could be increased to 8 gVS/l/d for the FPW and to 12 gVS/l/d for the OFMSW, operating at a HRT of 3 days. The results show a conclusion of 26% and 65% less reactor volume for the two-stage process compared to the single-stage process for the FPW and the OFMSW, respectively.

Place, publisher, year, edition, pages
Elsevier, 2014
Keywords
Resource Recovery
National Category
Industrial Biotechnology
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-1890 (URN)10.1016/j.ibiod.2014.06.008 (DOI)2320/14033 (Local ID)2320/14033 (Archive number)2320/14033 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Aslanzadeh, S., Ishola, M. M., Richards, T. & Taherzadeh, M. J. (2014). An Overview of Existing Individual Unit Operations. In: Biorefineries: Integrated Biochemical Processes for Liquid Biofuels. Elsevier Inc.
Open this publication in new window or tab >>An Overview of Existing Individual Unit Operations
2014 (English)In: Biorefineries: Integrated Biochemical Processes for Liquid Biofuels, Elsevier Inc. , 2014Chapter in book (Refereed)
Abstract [en]

BACKGROUND: Because of its extreme toxicity for microorganisms, the limonene content of citrus wastes (CWs) has been a major obstacle to the conversion of CWs to biofuels. The main objective of this study was to develop a new process for the utilization of CWs that can be economically feasible when the supply of CW is low.

RESULTS: Steam explosion pre-treatment was applied to improve the anaerobic digestibility of CWs, resulting in a decrease of initial limonene concentration by 94.3%. A methane potential of 0.537 ± 0.001 m 3 kg -1 VS (volatile solids) was obtained during the following batch digestion of treated CWs, corresponding to an increase of 426% compared with that of the untreated samples. Long-term effects of the treatment were further investigated by a semi-continuous co-digestion process. A methane production of 0.555 ± 0.0159 m 3 CH 4 kg -1 VS day -1 was achieved when treated CWs (corresponding to 30% of the VS load) were co-digested with municipal solid waste.

CONCLUSION: The process developed can easily be applied to an existing biogas plant. The equipment cost for this process is estimated to be one million USD when utilizing 10 000 tons CWs year -1. 8.4 L limonene and 107.4 m 3 methane can be produced per ton of fresh citrus wastes in this manner. 

Place, publisher, year, edition, pages
Elsevier Inc., 2014
Keywords
Citrus waste, Cost estimation, Limonene, Methane, Pre-treatment
National Category
Industrial Biotechnology
Research subject
Resource Recovery; Resource Recovery
Identifiers
urn:nbn:se:hb:diva-14804 (URN)10.1016/B978-0-444-59498-3.00001-4 (DOI)2-s2.0-84942614873 (Scopus ID)978-0-444-59498-3 (ISBN)
Available from: 2018-08-02 Created: 2018-08-02 Last updated: 2018-08-08Bibliographically approved
Kabir, M. M., Aslanzadeh, S., Teghammar, A., del Pilar Castillo, M., Taherzadeh, M. J. & Sárvári Horváth, I. (2014). Biogas production from lignocelluloses by N-methylmorpholine-N-oxide (NMMO) pretreatment: Achievements and Challenges. In: : . Paper presented at Green Gas Research Outlet Sweden, March 24-25. 2014, Gävle, Sweden.
Open this publication in new window or tab >>Biogas production from lignocelluloses by N-methylmorpholine-N-oxide (NMMO) pretreatment: Achievements and Challenges
Show others...
2014 (English)Conference paper, Published paper (Other academic)
Keywords
biogas, resource recovery
National Category
Industrial Biotechnology Chemical Engineering
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-7174 (URN)2320/13639 (Local ID)2320/13639 (Archive number)2320/13639 (OAI)
Conference
Green Gas Research Outlet Sweden, March 24-25. 2014, Gävle, Sweden
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-06-22Bibliographically approved
Aslanzadeh, S., Berg, A., Taherzadeh, M. J. & Sárvári Horváth, I. (2014). Biogas Production from N-Methylmorpholine-N-oxide (NMMO) Pretreated Forest Residues. Applied Biochemistry and Biotechnology, 172(6), 2998-3008
Open this publication in new window or tab >>Biogas Production from N-Methylmorpholine-N-oxide (NMMO) Pretreated Forest Residues
2014 (English)In: Applied Biochemistry and Biotechnology, ISSN 0273-2289, E-ISSN 1559-0291, Vol. 172, no 6, p. 2998-3008Article in journal (Refereed) Published
Abstract [en]

Lignocellulosic biomass represents a great potential for biogas production. However, a suitable pretreatment is needed to improve their digestibility. This study investigates the effects of an organic solvent, N-Methylmorpholine-N-oxide (NMMO) at temperatures of 120 and 90 °C, NMMO concentrations of 75 and 85 % and treatment times of 3 and 15 h on the methane yield. The long-term effects of the treatment were determined by a semicontinuous experiment. The best results were obtained using 75 % NMMO at 120 °C for 15 h, resulting in 141 % increase in the methane production. These conditions led to a decrease by 9 % and an increase by 8 % in the lignin and in the carbohydrate content, respectively. During the continuous digestion experiments, a specific biogas production rate of 92 NmL/gVS/day was achieved while the corresponding rate from the untreated sample was 53 NmL/gVS/day. The operation conditions were set at 4.4 gVS/L/day organic loading rate (OLR) and hydraulic retention time (HRT) of 20 days in both cases. NMMO pretreatment has substantially improved the digestibility of forest residues. The present study shows the possibilities of this pretreatment method; however, an economic and technical assessment of its industrial use needs to be performed in the future.

Place, publisher, year, edition, pages
Humana Press, Inc., 2014
Keywords
Anaerobic digestion, Biotechnology
National Category
Industrial Biotechnology Chemical Engineering
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-1851 (URN)10.1007/s12010-014-0747-z (DOI)000334432400016 ()24474331 (PubMedID)2320/13634 (Local ID)2320/13634 (Archive number)2320/13634 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Aslanzadeh, S. (2014). Pretreatment of cellulosic waste and high rate biogas production. (Doctoral dissertation). University of Borås, School of Engineering
Open this publication in new window or tab >>Pretreatment of cellulosic waste and high rate biogas production
2014 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The application of anaerobic digestion technology is growing worldwide, mainly because of its environmental benefits. Nevertheless, anaerobic degradation is a rather slow and sensitive process. One of the reasons is the recalcitrance nature of certain fractions of the substrate (e.g., lignocelluloses) used for microbial degradation; thus, the hydrolysis becomes the rate-limiting step. The other reason is that the degradation of organic matter is based on a highly dynamic, multi-step process of physicochemical and biochemical reactions. The reactions take place in a sequential and parallel way under symbiotic interrelation of a variety of anaerobic microorganisms, which all together make the process sensitive. The first stage of the decomposition of the organic matter is performed by fast growing (hydrolytic and acid forming) microorganisms, while in the second stage the organic acids produced are metabolized by the slow growing methanogens, which are more sensitive than the acidogens; thus, methanogenesis becomes the rate-limiting step. The first part of this work evaluates the effects of a pretreatment using an organic solvent, N-methylmorpholine-N-oxide (NMMO), on cellulose-based materials in order to overcome the challenge of biomass recalcitrance and to increase the rate of the hydrolysis. NMMO-pretreatment of straw separated from the cattle and horse manure resulted in increased methane yields, by 53% and 51%, respectively, in batch digestion tests. The same kind of pretreatment of the forest residues led to an increase by 141% in the methane production during the following batch digestion assays. The second part of this work evaluates the efficacy of a two-stage process to overcome the second challenge with methanogenesis as the rate-limiting step, by using CSTR (continuous stirred tank reactors) and UASB (up flow anaerobic sludge blanket) on a wide variety of different waste fractions in order to decrease the time needed for the digestion process. In the two-stage semi-continuous process, the NMMO-pretreatment of jeans increased the biogas yield due to a more efficient hydrolysis compared to that of the untreated jeans. The results indicated that a higher organic loading rate (OLR) and a lower retention time could be achieved if the material was easily degradable. Comparing the two-stage and the single-stage process, treating the municipal solid waste (MSW) and waste from several food processing industries (FPW), showed that the OLR could be increased from 2 gVS/l/d to 10 gVS/l /d, and at the same time the HRT could be decreased from 10 to 3 days, which is a significant improvement that could be beneficial from an industrial point of view. The conventional single stage, on the other hand, could only handle an OLR of 3 gVS/l/d and HRT of 7 days.

Place, publisher, year, edition, pages
University of Borås, School of Engineering, 2014
Series
Skrifter från Högskolan i Borås, ISSN 0280-381X ; 47
Keywords
Biogas, Two-stage anaerobic digestion, N-methylmorpholine N-oxide (NMMO) pretreatment, Lignocelluloses, Textile waste, Biofuels
National Category
Industrial Biotechnology Chemical Engineering
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-3684 (URN)2320/12853 (Local ID)978-91-87525-10-0 (ISBN)978-91-87525-11-7 (ISBN)2320/12853 (Archive number)2320/12853 (OAI)
Available from: 2015-12-04 Created: 2015-12-04 Last updated: 2016-08-19Bibliographically approved
Aslanzadeh, S., Rajendran, K. & Taherzadeh, M. J. (2014). Pretreatment of Lignocelluloses for Biogas and Ethanol Processes. In: Ram Sarup Singh, Ashok Pandey, Christian Larroche (Ed.), Advances in Industrial Biotechnology: (pp. 125-150). Asiatech Publishers Inc
Open this publication in new window or tab >>Pretreatment of Lignocelluloses for Biogas and Ethanol Processes
2014 (English)In: Advances in Industrial Biotechnology / [ed] Ram Sarup Singh, Ashok Pandey, Christian Larroche, Asiatech Publishers Inc , 2014, p. 125-150Chapter in book (Refereed)
Place, publisher, year, edition, pages
Asiatech Publishers Inc, 2014
Keywords
Resource Recovery
National Category
Industrial Biotechnology
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-5222 (URN)2320/14207 (Local ID)9789382332763 (ISBN)2320/14207 (Archive number)2320/14207 (OAI)
Available from: 2015-12-17 Created: 2015-12-17 Last updated: 2016-06-21Bibliographically approved
Aslanzadeh, S., Rajendran, K. & Taherzadeh, M. J. (2013). A comparative study between conventional and two stage anaerobic process: Effect of organic loading rate and hydraulic retention time. In: Shu Li, Jegatheesan Veeriah, Keir Greg, Kier Merrin, Chang Chia-Yuan (Ed.), : . Paper presented at The Sixth Annual Conference on the Challenges in Environmental Science and Engineering, Daegu, South Korea, 2013 10 29 - 2013 11 2. CESE 2013
Open this publication in new window or tab >>A comparative study between conventional and two stage anaerobic process: Effect of organic loading rate and hydraulic retention time
2013 (English)In: / [ed] Shu Li, Jegatheesan Veeriah, Keir Greg, Kier Merrin, Chang Chia-Yuan, CESE 2013 , 2013Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
CESE 2013, 2013
Keywords
two-stage anaerobic digestion, recirculation, rapid digestion, UASB, Biofuels
National Category
Industrial Biotechnology Chemical Engineering
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-7025 (URN)2320/12717 (Local ID)9780646912479 (ISBN)2320/12717 (Archive number)2320/12717 (OAI)
Conference
The Sixth Annual Conference on the Challenges in Environmental Science and Engineering, Daegu, South Korea, 2013 10 29 - 2013 11 2
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2016-06-28Bibliographically approved
Rajendran, K., Aslanzadeh, S., Johansson, F. & Taherzadeh, M. J. (2013). Experimental and economical evaluation of a novel biogas digester. Energy Conversion and Management, 74, 183-191
Open this publication in new window or tab >>Experimental and economical evaluation of a novel biogas digester
2013 (English)In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 74, p. 183-191Article in journal (Refereed) Published
Abstract [en]

Many developing countries face an energy demand to satisfy the daily needs of the people. Household biogas digesters are among the interesting solutions to meet the energy demands for cooking and lighting, and at the same time taking care of the kitchen wastes. In this study, a novel textile-based biogas digester was developed. The digester was evaluated for biogas production from a synthetic nutrient and an organic fraction of municipal solid waste (OFMSW) as substrates for more than a year. The obtained biogas productivity in both experiments was 570 L/kgVS/day, which indicates that the digester is as efficient in handling of OFMSW as the synthetic nutrients. Based on the obtained biogas production data, the techno-economic evaluation and sensitivity analysis for the process were performed, replacing LPG and kerosene consumption with biogas in households. A 2-m3 digester can supply the fuel needed for cooking for a family of 4–6 people. The sum of investment and 15-years operational costs of this digester was 656 USD, which can be compared with 1455 USD for subsidized-LPG and 975 USD for kerosene, respectively. The results from the sensitivity analysis show that it was a positive investment, unless the price of kerosene goes down to less than 0.18 USD/L.

Place, publisher, year, edition, pages
Elsevier Ltd, 2013
Keywords
Household digesters, Biogas, Cooking fuel, Techno-economic analysis
National Category
Engineering and Technology
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-1584 (URN)10.1016/j.enconman.2013.05.020 (DOI)000325302700020 ()2320/12380 (Local ID)2320/12380 (Archive number)2320/12380 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Jeihanipour, A., Aslanzadeh, S., Rajendran, K., Balasubramanian, G. & Taherzadeh, M. J. (2013). High-rate biogas production from waste textiles using a two-stage process. Renewable energy, 52, 128-135
Open this publication in new window or tab >>High-rate biogas production from waste textiles using a two-stage process
Show others...
2013 (English)In: Renewable energy, ISSN 0960-1481, E-ISSN 1879-0682, Vol. 52, p. 128-135Article in journal (Refereed) Published
Abstract [en]

The efficacy of a two-stage Continuously Stirred Tank Reactor (CSTR), modified as Stirred Batch Reactor (SBR), and Upflow Anaerobic Sludge Blanket Bed (UASB) process in producing biogas from waste textiles was investigated under batch and semi-continuous conditions. Single-stage and two-stage digestions were compared in batch reactors, where 20 g/L cellulose loading, as either viscose/polyester or cotton/polyester textiles, was used. The results disclosed that the total gas production from viscose/polyester in a two-stage process was comparable to the production in a single-stage SBR, and in less than two weeks, more than 80% of the theoretical yield of methane was acquired. However, for cotton/polyester, the two-stage batch process was significantly superior to the single-stage; the maximum rate of methane production was increased to 80%, and the lag phase decreased from 15 days to 4 days. In the two-stage semi-continuous process, where the substrate consisted of jeans textiles, the effect of N-methylmorpholine-N-oxide (NMMO) pretreatment was studied. In this experiment, digestion of untreated and NMMO-treated jeans textiles resulted in 200 and 400 ml (respectively) methane/g volatile solids/day (ml/g VS/day), with an organic loading rate (OLR) of 2 g VS/L reactor volume/day (g VS/L/day); under these conditions, the NMMO pretreatment doubled the biogas yield, a significant improvement. The OLR could successfully be increased to 2.7 g VS/L/day, but at a loading rate of 4 g VS/L/day, the rate of methane production declined. By arranging a serial interconnection of the two reactors and their liquids in the two-stage process, a closed system was obtained that converted waste textiles into biogas.

Place, publisher, year, edition, pages
Pergamon, 2013
Keywords
Rapid digestion, Biogas, NMMO pretreatment, UASB, NMMO, Waste textiles, Resursåtervinning
National Category
Engineering and Technology Bioenergy
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-1391 (URN)10.1016/j.renene.2012.10.042 (DOI)000314079200016 ()2320/11651 (Local ID)2320/11651 (Archive number)2320/11651 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-08-23Bibliographically approved
Aslanzadeh, S., Rajendran, K. & Taherzadeh, M. J. (2013). Pretreatment of lignocelluloses for biogas and ethanol processes. In: Ram Sarup Singh, Ashok Pandey, Christian Larroche (Ed.), Advances in Industrial Biotechnology: (pp. 125-150). I. K. International Publishing House
Open this publication in new window or tab >>Pretreatment of lignocelluloses for biogas and ethanol processes
2013 (English)In: Advances in Industrial Biotechnology / [ed] Ram Sarup Singh, Ashok Pandey, Christian Larroche, I. K. International Publishing House , 2013, p. 125-150Chapter in book (Other academic)
Place, publisher, year, edition, pages
I. K. International Publishing House, 2013
National Category
Industrial Biotechnology
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-5196 (URN)2320/13550 (Local ID)9789382332763 (ISBN)2320/13550 (Archive number)2320/13550 (OAI)
Available from: 2015-12-17 Created: 2015-12-17 Last updated: 2016-06-27Bibliographically approved
Organisations

Search in DiVA

Show all publications