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Pourbafrani, Mohammad
Alternative names
Publications (6 of 6) Show all publications
Pourbafrani, M., Forgacs, G., Sárvári Horváth, I. & Taherzadeh, M. J. (2011). Framställning av mångahanda biprodukter från fasta citrusrester. se SE 534774.
Open this publication in new window or tab >>Framställning av mångahanda biprodukter från fasta citrusrester
2011 (Swedish)Patent (Other (popular science, discussion, etc.))
Keywords
orange peels, citrus wastes, ethanol, biogas, limonene
National Category
Engineering and Technology Industrial Biotechnology
Research subject
Resource Recovery
Identifiers
urn:nbn:se:hb:diva-3334 (URN)2320/9653 (Local ID)2320/9653 (Archive number)2320/9653 (OAI)
Patent
SE SE 534774 (2011-12-13)
Available from: 2015-11-25 Created: 2015-11-25 Last updated: 2016-07-13Bibliographically approved
Pourbafrani, M. (2010). Citrus Waste Biorefinery: Process Development, Simulation and Economic Analysis. (Doctoral dissertation). Chalmers University of Technology
Open this publication in new window or tab >>Citrus Waste Biorefinery: Process Development, Simulation and Economic Analysis
2010 (English)Doctoral thesis, monograph (Other academic)
Abstract [en]

The production of ethanol and other sustainable products including methane, limonene and pectin from citrus wastes (CWs) was studied in the present thesis. In the first part of the work, the CWs were hydrolyzed using enzymes – pectinase, cellulase and β-glucosidase – and the hydrolyzate was fermented using encapsulated yeasts in the presence of the inhibitor compound ‘limonene’. However, the application of encapsulated cells may be hampered by the high price of encapsulation, enzymes and the low stability of capsules’ membrane at high shear stresses. Therefore, a process based on dilute-acid hydrolysis of CWs was developed. The limonene of the CWs was effectively removed through flashing of the hydrolyzate into an expansion tank. The sugars present in the hydrolyzate were converted to ethanol using a flocculating yeast strain. Then ethanol was distilled and the stillage and the remaining solid materials of the hydrolyzed CWs were anaerobically digested to obtain methane. The soluble pectin content of hydrolyzate can be precipitated using the produced ethanol. One ton of CWs with 20% dry weight resulted in 39.64 l ethanol, 45 m3 methane, 8.9 l limonene, and 38.8 kg pectin. The feasibility of the process depends on the transportation cost and the capacity of CW. For example, the total cost of ethanol with a capacity of 100,000 tons CW/year was 0.91 USD/L, assuming 10 USD/ton handling and transportation cost of CW to the plant. Changing the plant capacity from 25,000 to 400,000 tons CW per year results in reducing ethanol costs from 2.55 to 0.46 USD/L in an economically feasible process. Since this process employs a flocculating yeast strain, the major concern in design of the bioreactor is the sedimentation of yeast flocs. The size of flocs is a function of sugar concentration, time and flow. A CFD model of bioreactor was developed to predict the sedimentation of flocs and the effect of flow on distribution of flocs. The CFD model predicted that the flocs sediment when they are larger than 180 micrometer. The developed CFD model can be used in design and scale-up of the bioreactor. For the plants with low CW capacity, a steam explosion process was employed to eliminate limonene and the treated CW was used in a digestion plant to produce methane. The required cost of this pretreatment was about 0.90 million dollars for 10,000 tons/year of CWs.

Place, publisher, year, edition, pages
Chalmers University of Technology, 2010
Series
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie, ISSN 0346-718X ; 3069
Keywords
citrus waste, biorefinery, ethanol, biogas, Bioteknik
National Category
Chemical Process Engineering Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-3557 (URN)2320/6701 (Local ID)9789173853880 (ISBN)2320/6701 (Archive number)2320/6701 (OAI)
Note

Sponsorship:

Sparbankstiftelsen Sjuhärad, Kommunalförbundet i Sjuhärad, Brämhults juice AB

Available from: 2015-12-04 Created: 2015-12-04 Last updated: 2016-03-14
Pourbafrani, M. & Taherzadeh, M. (2009). Ethanol from Softwood: Process Simulation and Energy Analysis. In: : . Paper presented at The 2nd Nordic Wood Biorefinery Conference, Helsinki, September 2-4, 2009. NWBC 2009, The 2nd Nordic Wood Biorefinery Conference, Helsinki, Finland
Open this publication in new window or tab >>Ethanol from Softwood: Process Simulation and Energy Analysis
2009 (English)Conference paper, Poster (with or without abstract) (Other academic)
Place, publisher, year, edition, pages
NWBC 2009, The 2nd Nordic Wood Biorefinery Conference, Helsinki, Finland, 2009
Keywords
Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-6169 (URN)2320/5353 (Local ID)2320/5353 (Archive number)2320/5353 (OAI)
Conference
The 2nd Nordic Wood Biorefinery Conference, Helsinki, September 2-4, 2009
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2017-01-26Bibliographically approved
Pourbafrani, M., Talebnia, F. & Taherzadeh, M. (2009). Production of Bioethanol from Citrus Wastes by Encapsulated Yeast. In: Proceeding ISWA/APESB 2009 World Congress, Lissabon: . Paper presented at WTERT ISWA/APESB WORLD CONGRESS:Turning Waste into Ideas, Lisbon, October 12-15, 2009.. Proceeding ISWA/APESB 2009 World Congress
Open this publication in new window or tab >>Production of Bioethanol from Citrus Wastes by Encapsulated Yeast
2009 (English)In: Proceeding ISWA/APESB 2009 World Congress, Lissabon, Proceeding ISWA/APESB 2009 World Congress , 2009Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
Proceeding ISWA/APESB 2009 World Congress, 2009
Keywords
ethanol, citrus waste, encapsulation, baker's yeast, saccharomyces cerevisiae, Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-6220 (URN)2320/5591 (Local ID)2320/5591 (Archive number)2320/5591 (OAI)
Conference
WTERT ISWA/APESB WORLD CONGRESS:Turning Waste into Ideas, Lisbon, October 12-15, 2009.
Available from: 2015-12-22 Created: 2015-12-22 Last updated: 2017-01-25Bibliographically approved
Talebnia, F., Pourbafrani, M., Taherzadeh, M. J. & Lundin, M. (2008). Optimization study of citrus wastes Saccharification by dilute acid hydrolysis. BioResources, 3(1), 108-122
Open this publication in new window or tab >>Optimization study of citrus wastes Saccharification by dilute acid hydrolysis
2008 (English)In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 3, no 1, p. 108-122Article in journal (Refereed) Published
Abstract [en]

Optimization study of citrus wastes Saccharification by dilute acid hydrolysis

Abstract [en]

Optimization study of citrus wastes Saccharification by dilute acid hydrolysis

Abstract [en]

The effects of time, acid concentration, temperature and solid concentration on dilute-acid hydrolysis of orange peels were investigated. A central composite rotatable experimental design (CCRD) was applied to study the individual effects of these hydrolysis factors and also their interdependence effects. The enzymatic hydrolysis of the peels by cellulase, beta-glucosidase, and pectinase enzymes resulted in 72% dissolution of the peels, including 18.7% galacturonic acid and 53.3% of a total of glucose, fructose, galactose, and arabinose. Dilute-acid hydrolysis up to 210 C was not able to hydrolyze pectin to galacturonic acid. However, the sugar polymers were hydrolyzed at relatively low temperature. The optimum results were obtained at 116 degrees C, 0.5% sulfuric acid concentration, 6% solid fraction, and 12.9 min retention time. Under these conditions, the total sugars obtained at 41.8% dry peels and 2.6% of total hexose sugars were further degraded to hydroxymethylfurfural (HMF). No furfural was detected through these experiments from decomposition of pentoses.

Place, publisher, year, edition, pages
North Carolina State University, 2008
Keywords
orange peels, dilute-acid hydrolysis, experimental design, suger optimization, Energi och material
National Category
Other Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-2410 (URN)2320/3559 (Local ID)2320/3559 (Archive number)2320/3559 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01Bibliographically approved
Pourbafrani, M., Talebnia, F., Niklasson, C. & Taherzadeh, M. (2007). Protective Effect of Encapsulation in Fermentation of Limonene-contained Media and Orange Peel Hydrolyzate. International Journal of Molecular Sciences, 8(8), 777-787
Open this publication in new window or tab >>Protective Effect of Encapsulation in Fermentation of Limonene-contained Media and Orange Peel Hydrolyzate
2007 (English)In: International Journal of Molecular Sciences, ISSN 1422-0067, E-ISSN 1422-0067, Vol. 8, no 8, p. 777-787Article in journal (Refereed)
Abstract [en]

This work deals with application of encapsulation technology to eliminate inhibition of D-limonene in fermentation of orange wastes to ethanol. Orange peel was enzymatically hydrolyzed with cellulase and pectinase. However fermentation of the released sugars in this hydrolyzate by freely suspended S. cerevisiae failed due to inhibition of limonene. On the other hand, encapsulation of S. cerevisiae in alginate membranes was a powerful tool to eliminate inhibition of limonene. The encapsulated cells were able to ferment the orange peel hydrolyzate in 7 h, and produce ethanol with yield 0.44 g/g fermentable sugars. Cultivation of the encapsulated yeast in defined medium was successful, even in the presence of 1.5% (v/v) limonene. The capsules’ membranes were selectively permeable to the sugars and the other nutrients, but not limonene. While 1% (v/v) limonene was present in the culture, its concentration inside the capsules was not more than 0.054% (v/v).

Place, publisher, year, edition, pages
Molecular Diversity Preservation International (MDPI) AG., 2007
Keywords
orange peels, encapsulated yeast, alginate membrane, ethanol, limonene, enzymatic hydrolysis, Energi och material
National Category
Industrial Biotechnology
Identifiers
urn:nbn:se:hb:diva-2295 (URN)10.3390/i8080777 (DOI)2320/2958 (Local ID)2320/2958 (Archive number)2320/2958 (OAI)
Available from: 2015-11-13 Created: 2015-11-13 Last updated: 2017-12-01
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