Utilization of Biodiesel By-Products for Biogas Production

This contribution reviews the possibility of using the by-products from biodiesel production as substrates for anaerobic digestion and production of biogas. The process of biodiesel production is predominantly carried out by catalyzed transesterification. Besides desired methylesters, this reaction provides also few other products, including crude glycerol, oil-pressed cakes, and washing water. Crude glycerol or g-phase is heavier separate liquid phase, composed mainly by glycerol. A couple of studies have demonstrated the possibility of biogas production, using g-phase as a single substrate, and it has also shown a great potential as a cosubstrate by anaerobic treatment of different types of organic waste or energy crops. Oil cakes or oil meals are solid residues obtained after oil extraction from the seeds. Another possible by-product is the washing water from raw biodiesel purification, which is an oily and soapy liquid. All of these materials have been suggested as feasible substrates for anaerobic degradation, although some issues and inhibitory factors have to be considered.

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Anaerobic treatment of biodiesel by-products in a pilot scale reactor

Chemical Papers ◽

10.2478/s11696-011-0035-0 ◽

2011 ◽

Vol 65 (4) ◽

Cited By ~ 7

Author(s):

Nina Kolesárová ◽

Miroslav Hutňan ◽

Viera Špalková ◽

Rastislav Kuffa ◽

Igor Bodík

Keyword(s):

Crude Glycerol ◽

Biogas Production ◽

Rapeseed Meal ◽

Pilot Scale ◽

Anaerobic Treatment ◽

Biodiesel Production ◽

Term Operation ◽

Volumetric Loading ◽

By Products

AbstractIn this work, long-term operation of a pilot scale mixed anaerobic reactor processing crude glycerol and rapeseed meal is discussed. These materials are generated as by-products of biodiesel production. Mixed reactor was operated under mesophilic conditions for the period of 654 days. Total cumulative production of biogas reached 379 m3 (at atmospheric pressure and ambient temperature). Maximum volumetric loading achieved during the operation was 2.17 kg m−3 d−1 for the crude glycerol dose of 2 L. When dosing crude glycerol as a single substrate, average specific production of biogas of 0.76 m3 per L of the g-phase was achieved. The lack of nutrients in the g-phase had to be compensated by an addition of ammonium nitrogen in the form of urea into the reactor. Long term processing of crude glycerol demonstrated that accumulation of dissolved inorganic salts in the reactor can lead to inhibition of the methanogenic activity of microorganisms, causing breakdown of the system. Co-fermentation of crude glycerol with rapeseed meal provided stable biogas production and it was shown to be a feasible way of anaerobic degradation of these substrates. At the maximum volumetric load of 1.33 kg m−3 d−1 (500 mL of g-phase and 500 g of rapeseed meal), the average biogas production reached 0.58 m3 d−1.

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Anaerobic treatment of crude glycerol from biodiesel production

Water Science & Technology ◽

10.2166/wst.2015.345 ◽

2015 ◽

Vol 72 (8) ◽

pp. 1383-1389 ◽

Cited By ~ 4

Author(s):

M. M. Nakazawa ◽

W. R. S. Silva Júnior ◽

M. T. Kato ◽

S. Gavazza ◽

L. Florencio

Keyword(s):

Crude Glycerol ◽

Denaturing Gradient Gel Electrophoresis ◽

Biogas Production ◽

Oxygen Demand ◽

Experimental Period ◽

Anaerobic Treatment ◽

Biodiesel Production ◽

Uasb Reactor ◽

Anaerobic Sludge ◽

Reactor Performance

In this study, we evaluated the use of an up-flow anaerobic sludge blanket (UASB) reactor to treat crude glycerol obtained from cottonseed biodiesel production. The laboratory-scale UASB reactor (7.0 L) was operated at ambient temperature of 26.5°C with chemical oxygen demand (COD) concentrations between 0.5 and 8.0 g/L. The volatile fatty acid contents, pH, inorganic salt contents and biogas production were monitored during a 280-day experimental period. Molecular biology techniques were used to assess the microbial diversity in the bioreactor. The reactor achieved COD removal efficiencies of up to 92% except during one phase when the efficiency decreased to 81%. Biogas production remained stable throughout the experimental period, when the fraction converted to methane reached values as high as 68%. The profile of the denaturing gradient gel electrophoresis (DGGE) bands suggested slight changes in the microbial community during reactor operation. The overall results indicated that the crude glycerol from biodiesel production can serve as a suitable substrate for anaerobic degradation with a stable reactor performance and biogas production as long as the applied organic loads are up to 8.06 kg COD/m3·d.

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Anaerobic treatment of rapeseed meal

Chemical Papers ◽

10.2478/s11696-013-0318-8 ◽

2013 ◽

Vol 67 (12) ◽

Cited By ~ 4

Author(s):

Nina Kolesárová ◽

Miroslav Hutňan ◽

Viera Špalková ◽

Michal Lazor

Keyword(s):

Biogas Production ◽

Rapeseed Meal ◽

Anaerobic Treatment ◽

Biodiesel Production ◽

Organic Loading Rate ◽

Laboratory Model ◽

Continuous Stirred Tank Reactor ◽

Methanogenic Activity ◽

Term Operation

AbstractRapeseed meal is a solid by-product obtained from rapeseed after oil extraction. This contribution summarises experiences from batch experiments as well as the long-term processing of this substrate in a laboratory stirred anaerobic reactor (continuous stirred-tank reactor). On the basis of the batch tests of hydrolysis, acidogenesis, and methanogenic activity, it was concluded that the anaerobic degradation of rapeseed meal can be performed using a one-step system and it is not necessary to include a hydrolytic-acidogenic step prior to the methanogenic step. Although the methanogenic potential of rapeseed meal appears to be very promising, the long-term processing as a single substrate led to serious problems arising from the inhibitory effects. It was, therefore, co-fermented with crude glycerol from biodiesel production. From the long-term operation of the laboratory model, it may be stated that, due to the co-fermentation of by-products from biodiesel production, the individual inhibition effects can be suppressed to a large extent and biogas production can be stabilised. The maximum organic loading rate in the continuous stirred reactor achieved 2.42 kg m−3 d−1 of volatile solids (15 g of rapeseed meal and 20 mL of gas-phase), which was 3.13 kg m−3 d−1 of chemical oxygen demand.

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Archaeal Production of Polyhydroxyalkanoate (PHA) Co- and Terpolyesters from Biodiesel Industry-Derived By-Products

Archaea ◽

10.1155/2013/129268 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 88

Author(s):

Carmen Hermann-Krauss ◽

Martin Koller ◽

Alexander Muhr ◽

Hubert Fasl ◽

Franz Stelzer ◽

...

Keyword(s):

Crude Glycerol ◽

Molar Mass ◽

Molar Fraction ◽

Volumetric Productivity ◽

Biodiesel Production ◽

Haloferax Mediterranei ◽

Average Molar Mass ◽

Melting Temperatures ◽

Pure Glycerol ◽

By Products

The archaeonHaloferax mediterraneiwas selected for production of PHA co- and terpolyesters using inexpensive crude glycerol phase (CGP) from biodiesel production as carbon source. CGP was assessed by comparison with the application of pure glycerol. Applying pure glycerol, a copolyester with a molar fraction of 3-hydroxybutyrate (3HB) of 0.90 mol/mol and 3-hydroxyvalerate (3HV) of 0.10 mol/mol, was produced at a volumetric productivity of 0.12 g/Lh and an intracellular PHA content of 75.4 wt.-% in the sum of biomass protein plus PHA. Application of CGP resulted in the same polyester composition and volumetric productivity, indicating the feasibility of applying CGP as feedstock. Analysis of molar mass distribution revealed a weight average molar massMwof 150 kDa and polydispersityPiof 2.1 for pure glycerol and 253 kDa and 2.7 for CGP, respectively; melting temperatures ranged between 130 and 140°C in both setups. Supplyingγ-butyrolactone as 4-hydroxybutyrate (4HB) precursor resulted in a poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyvalerate-co-4-hydroxybutyrate] (PHBHV4HB) terpolyester containing 3HV (0.12 mol/mol) and 4HB (0.05 mol/mol) in the poly[(R)-3-hydroxybutyrate] (PHB) matrix; in addition, this process runs without sterilization of the bioreactor. The terpolyester displayed reduced melting (melting endotherms at 122 and 137°C) and glass transition temperature (2.5°C), increased molar mass (391 kDa), and a polydispersity similar to the copolyesters.

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Assessment of gross calorific value of crop and bio-energy residues

Research in Agricultural Engineering ◽

10.17221/13/2017-rae ◽

2018 ◽

Vol 64 (No. 3) ◽

pp. 121-127

Author(s):

Jóvér János ◽

Antal Károly ◽

Zsembeli József ◽

Blaskó Lajos ◽

Tamás János

Keyword(s):

Crop Residues ◽

Biogas Production ◽

Calorific Value ◽

Nutrient Content ◽

Energy Crop ◽

Alkali Content ◽

Oil Cakes ◽

Significant Difference ◽

Agricultural Use ◽

By Products

This study assessed the gross calorific values (GCV) of crop and bio-energy residues. In addition, it assessed the calorific values of sweet sorghum to clarify its potential as energy crop in the region. Furthermore, it statistically analysed the ash remaining after burning three bio-energy residues, bagasse, oil cakes and fermented sludge of biogas production, to identify their potential for agricultural use. Finally, the study calculated alkali content based on nutrient content and GCVs. Significant differences were found among the GCVs of the investigated materials. Among the crop residues, the least significant difference (LSD) (P ≤ 0.05) of the calorimetric values was 76.26 kJ/kg, and among the by-products of bio-energy production, it was 20.80 kJ/kg. Significant differences were also found in nutrient content. In the case of the alkali content of bio-energy residues, the LSD was 0.04 kJ·kg–1. For the bagasse and compost, the study recommends some technical operations to avoid slagging.

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Conversion of Crude Glycerol from by-Product Biodiesel into Bio-additive of Fuel through Acetylation Reaction based on Modified Zeolite Catalyst

ALCHEMY ◽

10.18860/al.v7i2.8193 ◽

2019 ◽

Vol 7 (2) ◽

pp. 46 ◽

Cited By ~ 1

Author(s):

Heny Dewajani ◽

Windi Zamrudy ◽

Hadi Saroso ◽

Satria Paramarta ◽

Wahyudianto Mulya

Keyword(s):

Acetic Acid ◽

Alternative Fuels ◽

Crude Glycerol ◽

Zeolite Catalyst ◽

Acid Catalyst ◽

Biodiesel Production ◽

Esterification Reaction ◽

Fuel Quality ◽

Nickel Metal ◽

By Products

Biodiesel is one of the alternative fuels produced from the transesterification reaction between triglycerides and alcohols with glycerol by-products. So far, the resulting crude glycerol has not been maximally utilized because of its low purity. So, it is necessary to purify glycerol before turning it into a more useful compound. The purified glycerol can be reacted with acetic acid within esterification reaction (acetylation process) using an acid catalyst to produce glycerol triacetate (triacetin). One of the uses of triacetin as an additive in gasoline and biodiesel. The purpose of this study is to utilize glycerol from by-products from biodiesel production to bio-additive materials that can improve fuel quality and are environmentally friendly. The method used in this study begins with the purification of crude glycerol, modification of zeolite catalyst with impregnated of nickel metal followed by an acetylation reaction which held on temperature of 100°C for 60 min. The experimental results are analyzed using base titration to determine the remaining unreacted acids and are applied as bio-additives by adding them to commercial fuels and measured the increasing octane numbers. The result shows that the reaction conversion increases with increasing mole ratio of reactants and catalysts with the best results in the mole ratio of acetic acid and glycerol is 9:1 and catalyst 5% by weight of acetic acid with a conversion of 66.02%. As bio-additives the reaction product could increase the octane number of commercial fuel by 6.5 up to 8.5%. Keywords: glycerol, acetylation reaction, mofified zeolite, bio-additive

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The impact of crude glycerol from biodiesel production and its trace element content on biomethane production in a batch experiment: modelling as a step towards impartial routine comparison of results

Acta hydrotechnica ◽

10.15292/acta.hydro.2021.02 ◽

2021 ◽

pp. 11-24

Author(s):

Sabina Kolbl Repinc ◽

Leon Deutsch ◽

Dragiša Savić ◽

Franci Steinman ◽

Bojana Danilović ◽

...

Keyword(s):

Trace Element ◽

Crude Glycerol ◽

Biogas Production ◽

Biodiesel Production ◽

Batch Experiment ◽

Inorganic Salts ◽

Lag Phase ◽

Daily Routine ◽

Negative Effects ◽

Biomethane Production

In this study, crude glycerol from the biodiesel industry was tested as a co-substrate in biogas production. To investigate the influence of crude glycerol and the underlying trace element (TE) content on the efficiency of biomethane production, a batch experiment using Automatic Methane Potential Test System (AMPTS II) was carried out. The single addition of crude glycerol significantly contributed only to the total content of K (14.4%), Si (17.3%), and P (11.6%), whereas the contributions of other metals were within the range of other substrates. The addition of crude glycerol increased biomethane production, however, its utilization beyond 1% of total volume resulted in prolonged lag phase and final cessation of biomethane production. The negative effects of inorganic salts present in crude glycerol were reflected in progressively diminishing parts of glycerol and methanol being utilized in its anaerobic digestion, posing serious problems for daily routine use. A nonlinear least square regression analysis was performed to fit the Gompertz, Logistic, Transfer, and Richards models to biomethane production. The most suitable model was the Richards model, exhibiting the best fit to the experimental curves for complex substrates. Glycerol fractions remaining after biodiesel production have to be pre-tested for their negative effects on the content of TEs and inorganic salts, lag phase in biogas production, before they are used as co-substrates in biogas production phase.

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Biodiesel-Derived Glycerol Obtained from Renewable Biomass—A Suitable Substrate for the Growth of Candida zeylanoides Yeast Strain ATCC 20367

Microorganisms ◽

10.3390/microorganisms7080265 ◽

2019 ◽

Vol 7 (8) ◽

pp. 265 ◽

Cited By ~ 8

Author(s):

Laura Mitrea ◽

Floricuța Ranga ◽

Florinela Fetea ◽

Francisc Vasile Dulf ◽

Alexandru Rusu ◽

...

Keyword(s):

Crude Glycerol ◽

Carbon Sources ◽

Biodiesel Production ◽

Bioreactor Cultivation ◽

Renewable Biomass ◽

Pure Glycerol ◽

Cultivation Process ◽

By Products ◽

Candida Zeylanoides ◽

Main Carbon

Used kitchen oil represents a feasible and renewable biomass to produce green biofuels such as biodiesel. Biodiesel production generates large amounts of by-products such as the crude glycerol fraction, which can be further used biotechnologically as a valuable nutrient for many microorganisms. In this study, we transesterified used kitchen oil with methanol and sodium hydroxide in order to obtain biodiesel and crude glycerol fractions. The crude glycerol fraction consisting of 30% glycerol was integrated into a bioreactor cultivation process as a nutrient source for the growth of Candida zeylanoides ATCC 20367. Cell viability and biomass production were similar to those obtained with batch cultivations on pure glycerol or glucose as the main nutrient substrates. However, the biosynthesis of organic acids (e.g., citric and succinic) was significantly different compared to pure glycerol and glucose used as main carbon sources.

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Digestion of sludge and organic waste in the sustainability concept for Malmö, Sweden

Water Science & Technology ◽

10.2166/wst.2004.0634 ◽

2004 ◽

Vol 49 (10) ◽

pp. 163-169 ◽

Cited By ~ 18

Author(s):

J. la Cour Jansen ◽

C. Gruvberger ◽

N. Hanner ◽

H. Aspegren ◽

Â Svärd

Keyword(s):

Anaerobic Digestion ◽

Organic Waste ◽

Biogas Production ◽

Treatment Plant ◽

Pilot Scale ◽

Anaerobic Treatment ◽

Household Waste ◽

Biogas Yield ◽

Different Types ◽

Pre Treatment

Anaerobic digestion of sludge has been part of the treatment plant in Malmö for many years and several projects on optimisation of the digestion process have been undertaken in full scale as well as in pilot scale. In order to facilitate a more sustainable solution in the future for waste management, solid waste organic waste is sorted out from households for anaerobic treatment in a newly built city district. The system for treatment of the waste is integrated in a centralised solution located at the existing wastewater treatment plant. A new extension of the digester capacity enables separate as well as co-digestion of sludge together with urban organic waste from households, industry, restaurants, big kitchens, food stores, supermarkets, green markets etc. for biogas production and production of fertiliser. Collection and pre-treatment of different types of waste are in progress together with examination of biogas potential for different types of organic waste. Collection of household waste as well as anaerobic digestion in laboratory and pilot scale has been performed during the last year. It is demonstrated that organic household waste can be digested separately or in combination with sludge. In the latter case a higher biogas yield is found than should be expected from digestion of the two materials separately. Household waste from a system based on collection of organic waste from grinders could be digested at mesophilic conditions whereas digestion failed at thermophilic conditions.

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Anaerobic Degradation of Raw Coconut Waste for Biogas Production

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.b3007.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 3130-3131

Keyword(s):

Electrical Conductivity ◽

Anaerobic Degradation ◽

Efficient Solution ◽

Biogas Production ◽

Lignin Content ◽

Solution Treatment ◽

Anaerobic Treatment ◽

High Electrical Conductivity ◽

Coir Pith ◽

High Lignin Content

Disposal of coconut coir waste has been a difficult task for the coir industry. Coir pith is being piled up in the outskirts of the coir industry. A solution to the coir pith disposal is the biogas production from it. Raw coir pith without any treatment was tested for its potential to produce biogas. There was very little biogas generated from raw coir pith. Due to the constraints of high electrical conductivity and high lignin content, direct anaerobic treatment of raw coir pith cannot be an efficient solution. Treatment of coir pith is required for increasing the quantity of biogas produced

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