Biogas Production Using Slaughterhouse Wastewater Co-digested with Domestic Sludge

The paper investigates producing biogas using Co-digestion of slaughterhouse wastewater (SHW) with primary sludge (PS). Lab experiments were executed at mesophilic condition (35±2°C). Two experiments were performed; the first in a 2000 ml vessel and the second in 600 ml serum bottles, both to mimic batch bioreactors. Among others, acidity (pH), alkalinity (ALK), and volatile fatty acids (VFA) were measured before and after the digestion process. The daily biogas and methane production were also measured. The experiments showed that Co-digestion achieved maximum biogas yield at 499.8 Nml Biogas/g VS fed. The biogas yield for PS and SHW were 411.5 Nml biogas /g VS fed and 433.8 Nml biogas /g VS fed respectively. CH4 yield from the Co-digestion was the highest compared to digest SHW separately. This proves the occurrence of inhibition in methanogenesis activity. The VFA final concentration was higher than the initial concentration for digest SHW.

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Chemically Enhanced Primary Sludge as an Anaerobic Co-Digestion Additive for Biogas Production from Food Waste

Processes ◽

10.3390/pr7100709 ◽

2019 ◽

Vol 7 (10) ◽

pp. 709 ◽

Cited By ~ 2

Author(s):

Xiaorong Kang ◽

Yali Liu

Keyword(s):

Chemical Oxygen Demand ◽

Food Waste ◽

Volatile Fatty Acids ◽

Biogas Production ◽

Oxygen Demand ◽

Mechanism Analysis ◽

Primary Sludge ◽

Biogas Yield ◽

Batch Tests ◽

Solids Removal

In order to overcome process instability and buffer deficiency in the anaerobic digestion of mono food waste (FW), chemically enhanced primary sludge (CEPS) was selected as a co-substrate for FW treatment. In this study, batch tests were conducted to study the effects of CEPS/FW ratios on anaerobic co-digestion (coAD) performances. Both soluble chemical oxygen demand (SCOD) and protease activity were decreased, with the CEPS/FW mass ratio increasing from 0:5 to 5:0. However, it was also found that the accumulation of volatile fatty acids (VFAs) was eliminated by increasing the CEPS/FW ratio, and that corresponding VFAs concentrations decreased from 13,872.97 to 1789.98 mg chemical oxygen demand per L (mg COD/L). In addition, the maximum value of cumulative biogas yield (446.39 mL per g volatile solids removal (mL/g VSsremoval)) was observed at a CEPS/FW ratio of 4:1, and that the tendency of coenzyme F420 activity was similar to biogas production. The mechanism analysis indicated that Fe-based CEPS relived the VFAs accumulation caused by FW, and Fe(III) induced by Fe-based CEPS enhanced the activity of F420. Therefore, the addition of Fe-based CEPS provided an alternative method for FW treatment.

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Co-digestion of concentrated black water and kitchen refuse in an accumulation system within the DESAR (decentralized sanitation and reuse) concept

Water Science & Technology ◽

10.2166/wst.2003.0235 ◽

2003 ◽

Vol 48 (4) ◽

pp. 121-128 ◽

Cited By ~ 20

Author(s):

K. Kujawa-Roeleveld ◽

T. Elmitwalli ◽

A. Gaillard ◽

M. van Leeuwen ◽

G. Zeeman

Keyword(s):

Biogas Production ◽

High Strength ◽

Buffering Capacity ◽

Ammonium Concentration ◽

Equivalent Amount ◽

Process Stability ◽

Primary Sludge ◽

Biogas Yield ◽

Black Water ◽

Accumulation System

Co-digestion of concentrated black water and kitchen refuse within the DESAR concept was the objective of this pilot research. The digestion took place in two, non-mixed accumulation reactors (AC1 and AC2) inoculated with digested primary sludge from a WWTP at a temperature of 20°C for a period of around 150 days. Reactor AC1 was fed with a mixture of faeces, urine and kitchen refuse in the equivalent amount that one individual generates per day. The AC2 was fed with a mixture of faeces and kitchen refuse in the equivalent amount that two individuals produce per day. Some contribution of urine to AC2 was not to be avoided. Detailed characterisation of waste(water) was performed. The performance of the stratified reactor was followed by monitoring the reactor content for several reactors' heights as well as being based on the biogas production. In general the system exposed good process stability. The methanisation of 34 and 61% was obtained for AC1 and AC2 respectively. The biogas yield was 26.5 and 50.8 L/p/d for the respective reactors. Proper choice of inoculum as well as good buffering capacity did not lead to accumulation of VFA and an inhibitive effect due to relatively high ammonium concentration. The chosen process is a promising technology showing good process stability especially for high strength influent.

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Anaerobic digestion of co-mingled municipal solid waste and sewage sludge

Water Science & Technology ◽

10.2166/wst.1998.0121 ◽

1998 ◽

Vol 38 (2) ◽

pp. 127-132 ◽

Cited By ~ 18

Author(s):

N. Hamzawi ◽

K. J. Kennedy ◽

D. D. McLean

Keyword(s):

Sewage Sludge ◽

Municipal Solid Waste ◽

Solid Waste ◽

Biogas Production ◽

Empirical Models ◽

Organic Fraction ◽

Primary Sludge ◽

Digestion Process ◽

Solids Concentration ◽

Anaerobic Biodegradability

This study evaluated the technical feasibility of the anaerobic co-digestion process in the context of typical North American solid waste. Using biological activity tests, an optimal mixture was identified with 25% organic fraction of municipal solid waste (OFMSW) and 75% sewage sludge (65% raw primary sludge (RAW), 35% thickened WAS (TWAS)) based on biogas production. Also, based on the rate of biogas production, the most anaerobically biodegradable components of the OFMSW were paper and grass. The TWAS and the newspaper were found to be the least biodegradable components. Lab-scale testing indicated that alkaline pretreatment increased the biodegradability of the sewage sludge/OFMSW mixture the most, as compared to the untreated control. Thermochemically pretreated feedstocks inhibited anaerobic biodegradability as compared to the control, whereas the anaerobic biodegradability of thermally pretreated feed was not found to be significantly different from that of the control. Empirical models were developed based on alkaline dose, feed total solids concentration and particle size for biogas production and removal of TS and VS. All three experimental factors were found to be significant with respect to the response variables studied.

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Volatile fatty acid production in aerobic thermophilic pre-treatment of primary sludge

Water Science & Technology ◽

10.2166/wst.1997.0410 ◽

1997 ◽

Vol 36 (11) ◽

pp. 189-196 ◽

Cited By ~ 8

Author(s):

K. B. McIntosh ◽

J. A. Oleszkiewicz

Keyword(s):

Fatty Acid ◽

Flow Rate ◽

Volatile Fatty Acid ◽

Volatile Fatty Acids ◽

Final Concentration ◽

Anoxic Condition ◽

Fatty Acid Production ◽

Primary Sludge ◽

Soluble Organic Carbon ◽

Pre Treatment

The efficiency of volatile fatty acid (VFA) production in a thermophilic aerobic digester (TAD) process using primary sludge was studied under two oxygenation states and detentions times ranging from 12 to 24 hours. The highest VFA concentration increase occurred in the 18 hour anaerobic aerated digester (O2 flow rate: 0.025 m3/m3·h; ORP: less than -300 mV) from 0.047 mg HAc/mg VSS in the feed to 0.106 mg HAc/mg VSS in the effluent. The anoxic condition (O2 flow rate: 0.14 m3/m3·h; ORP: between 0 to -225 mV) resulted in VFA utilisation and a final concentration of only 0.001 mg HAc/mg VSS. Under the anaerobic aerated condition, acetic acid constituted the largest fraction of short chain volatile fatty acids at an average of 60.4% and propionic trailed at 19.3%. The fraction of butyric and valeric acids were 12.2% and 8.1% respectively. It was found that with a decreasing oxygen supply and a decreasing detention time (HRT), the soluble organic carbon to ammonia ratio (SOC:NH3) increased.

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Effect of Millet Stalks and Shea Nut Shells on Biogas Production

The Journal of Solid Waste Technology and Management ◽

10.5276/jswtm/2021.292 ◽

2021 ◽

Vol 47 (2) ◽

pp. 292-296

Author(s):

Cosmos Moki Elinge ◽

Ayodeji Rapheal Ige ◽

Morenike O. Adesina ◽

Harrison Ogala ◽

Lawal Gusau Hassan ◽

...

Keyword(s):

Moisture Content ◽

Organic Compounds ◽

Anaerobic Condition ◽

Biogas Production ◽

Biogas Yield ◽

Moisture Contents ◽

Average Production ◽

Good Material ◽

Before And After

Biogas production undergoes decomposition of organic compounds under anaerobic condition. This present work investigated the yield of biogas production from Shea nut shell and millet stalk and their blends with sheep dung. It was revealed that sheep dung (control) had the highest yield with an average production of 187.8 ml of gas for 102 days followed by sheanut shell - sheep dung blends which had 123.3 ml of gas for 102 days. Millet stalk - sheep dung blends recorded 75.9 ml of gas for 79 days. Shea nut shell and millet stalk presented 31.5 ml of gas for 81 days and 7.1 ml of gas for 48 days respectively while the pH for production ranged from 10.1 to 4.6. The moisture contents recorded for millet stalk, Shea nut shell and sheep dung before and after production were 40%, 45%, 65% and 80%, 65%, 85 respectively, and also the recorded ash contents before and after production were, 35%, 45%, 40% and 85%, 75%, 65%, respectively. It was observed that the blending of Shea nut shell and sheep dung greatly improves biogas yield while Millet stalks alone are good material for biogas production at a reasonable pH and moisture content values.

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Anaerobic digestion of deproteinated cheese whey

Journal of Dairy Research ◽

10.1017/s0022029900024365 ◽

1985 ◽

Vol 52 (3) ◽

pp. 457-467 ◽

Cited By ~ 17

Author(s):

Johannes De Haast ◽

Trevor J. Britz ◽

Johannes C. Novello ◽

Emilige W. Verwey

Keyword(s):

Volatile Fatty Acids ◽

Biogas Production ◽

Fixed Bed ◽

Oxygen Demand ◽

Ammonia Level ◽

Fixed Bed Reactor ◽

Total Carbon ◽

Ammonia Toxicity ◽

Biogas Yield ◽

Titration Curves

SUMMARYWhey and deproteinated whey preparations with different carbon: nitrogen (C/N) ratios ranging from 7·5 to 73 were digested anaerobically in a downflow stationary fixed-bed reactor at 35 °C with a hydraulic retention time of 5 d. Effluent and biogas parameters indicated that no decrease in digestion and stability occurred at the highest C/N ratio. Chemical oxygen demand (COD) removal averaged 88%, while volatile fatty acids were maintained at a low level (< 500 mg l–1). Biogas yield averaged 0·423 m3kg–1COD and the methane content of the biogas varied between 57 and 63%. Ammonia toxicity occurred at a C/N ratio of 7/5 in the substrate feed. Virtually no ammonia N was detected in the effluent when whey substrates with C/N ratios of 50 and 73 were fed. Titration curves showed that buffer intensities in the effluent were not affected by a decrease in ammonia level. A decrease in the biomass content of the effluent which occurred as a result of the increase in C/N ratio of the substrate did not cause any rate limiting effect on biogas production. The removal of protein from the whey caused a reduction in the ratio of COD: total carbon in the whey. On average 59% of the carbon in the substrate was converted to biogas.

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Assessment of Multiple Anaerobic Co-Digestions and Related Microbial Community of Molasses with Rice-Alcohol Wastewater

Energies ◽

10.3390/en13184866 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4866 ◽

Cited By ~ 1

Author(s):

Sohail Khan ◽

Fuzhi Lu ◽

Qiong Jiang ◽

Chengjian Jiang ◽

Muhammad Kashif ◽

...

Keyword(s):

Microbial Communities ◽

Volatile Fatty Acids ◽

Biogas Production ◽

Removal Rate ◽

Cod Removal ◽

Ion Concentration ◽

Organic Loading Rate ◽

Digestion Process ◽

Cod Removal Rate ◽

Archaeal Communities

Molasses is a highly dense and refined byproduct produced in the sugarcane industry, and it contains high amounts of degradable compounds. Through bioconversion, these compounds can be transformed into renewable products. However, the involved biological process is negatively influenced by the high chemical oxygen demand (COD) of molasses and ion concentration. The co-digestion of molasses with rice-alcohol wastewater (RAW) was compared with its mono-digestion at an increasing organic loading rate (OLR). Both processes were assessed by detecting the COD removal rate, the methane contents of biogas, and the structure and composition of microbial communities at different stages. Results showed that the co-digestion is stable up to a maximum OLR of 16 g COD L−1 d−1, whereas after the acclimatization phase, the mono-digestion process was disturbed two times, which occurred at a maximum OLR of 9 and 10 g COD L−1 d−1. The volatile fatty acids (VFAs) observed were 2059.66 mg/L and 1896.9 mg/L, which in mono-digestion causes the inhibition at maximum OLRs. In the co-digestion process, the concomitant COD removal rates and methane content recorded was 90.72 ± 0.63% 64.47% ± 0.59% correspondingly. While in the mono-digestion process, high COD removal rate and methane contents observed were 89.29 ± 0.094% and 61.37 ± 1.06% respectively. From the analysis of microbial communities, it has been observed that both the bacterial and archaeal communities respond differently at unlike stages. However, in both processes, Propionibacteriaceae was the most abundant family in the bacterial communities, whereas Methanosaetaceae was abundant in the archaeal communities. From the current study, it has been concluded that that rice-alcohol wastewater could be a good co-substrate for the anaerobic digestion of molasses in terms of COD removal rate and methane contents production, that could integrate molasses into progressive biogas production with high OLR.

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THE EFFECT OF IRON SALT ON ANAEROBIC DIGESTION AND PHOSPHATE RELEASE TO SLUDGE LIQUOR / GELEŽIES DRUSKOS ĮTAKA ANAEROBINIO DUMBLO PŪDYMO PROCESUI IR FOSFATŲ IŠSISKYRIMUI Į DUMBLO VANDENĮ

Mokslas - Lietuvos ateitis ◽

10.3846/mla.2011.097 ◽

2011 ◽

Vol 3 (5) ◽

pp. 123-126

Author(s):

Svetlana Ofverstrom ◽

Regimantas Dauknys ◽

Ieva Sapkaitė

Keyword(s):

Anaerobic Digestion ◽

Phosphorus Content ◽

Wastewater Treatment Plants ◽

Biogas Production ◽

Iron Salt ◽

Digested Sludge ◽

Sludge Treatment ◽

Primary Sludge ◽

Digestion Process ◽

Iron Salts

Iron salts are used at wastewater treatment plants (WWTPs) for several reasons: for removing chemical phosphorus, preventing from struvite formation and reducing the content of hydrogen sulfide (H2S) in biogas. Anaerobic digestion is a common scheme for sludge treatment due to producing biogas that could be used as biofuel. Laboratory analysis has been carried out using anaerobic digestion model W8 (Armfield Ltd, UK) to investigate any possible effect of adding FeCl3 on the anaerobic digestion of primary sludge (PS) and waste activated sludge (WAS) mixture as well as on releasing phosphates to digested sludge liquor. The obtained results showed that FeCl3 negatively impacted the anaerobic digestion process by reducing the volume of produced biogas. Fe-dosed sludge (max) produced 30% less biogas. Biogas production from un-dosed and Fe-dosed sludge (min) was similar to the average of 1.20 L/gVSfed. Biogas composition was not measured during the conducted experiments. Phosphorus content in sludge liquor increased at an average of 38% when digesting sludge without ferric chloride dosing. On the contrary, phosphate content in sludge liquor from digested Fe-dosed sludge decreased by approx. 80%. Santrauka Nuotekų valymo įrenginiuose geležies druskos naudojamos cheminiam fosforui šalinti, sieros vandeniliui biodujose mažinti ir struvito nuogulų formavimosi prevencijai. Tyrimai atlikti laboratorinėmis sąlygomis naudojant anaerobinio pūdymo modelį W8 (Armfield Ltd., Didžioji Britanija) ir pūdant pirminio perteklinio dumblo mišinį, į kurį buvo dedama geležies druskos, siekiant nustatyti geležies druskos naudojimo efektą anarobinio pūdymo procesui ir fosfatų išsiskyrimui į dumblo vandenį. Rezultatai parodė, kad pūdant dumblą be geležies druskos ir dedant geležies druskos minimalią dozę, susidarė vidutiniškai vienodi kiekiai biodujų (mL/gBSMtiekiam.), bet į pūdomą dumblą dedant maksimalią geležies dozę, biodujų išeiga vidutiniškai sumažėjo 30 %. Į pūdomą dumblą nededant geležies chlorido, fosfatų koncentracija dumblo vandenyje vidutiniškai padidėjo 38 %. Ir priešingai, geležies chlorido dozės fosfatų koncentraciją pūdyto dumblo vandenyje sumažino 80 %.

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Effects of Hydrothermal Pretreatment and Hydrochar Addition on the Performance of Pig Carcass Anaerobic Digestion

Frontiers in Microbiology ◽

10.3389/fmicb.2021.622235 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jie Xu ◽

Hongjian Lin ◽

Kuichuan Sheng

Keyword(s):

Anaerobic Digestion ◽

Volatile Fatty Acids ◽

Biogas Production ◽

Oxygen Demand ◽

Ammonia Concentration ◽

Hydrothermal Pretreatment ◽

Biogas Yield ◽

Stirred Tank Reactors ◽

Liquid Products ◽

Pig Carcasses

Proper disposal and utilization of dead pig carcasses are problems of public concern. The combination of hydrothermal pretreatment (HTP) and anaerobic digestion is a promising method to treat these wastes, provided that digestion inhibition is reduced. For this reason, the aim of this work was to investigate the optimal HTP temperature (140–180°C) for biogas production during anaerobic digestion of dead pigs in batch systems. In addition, the effects of hydrochar addition (6 g/L) on anaerobic digestion of pork products after HTP in continuous stirred tank reactors (CSTR) were determined. According to the results, 90% of lipids and 10% of proteins present in the pork were decomposed by HTP. In addition, the highest chemical oxygen demand (COD) concentration in liquid products (LP) reached 192.6 g/L, and it was obtained after 170°C HTP. The biogas potential from the solid residue (SR) and LP was up to 478 mL/g-VS and 398 mL/g-COD, respectively. A temperature of 170°C was suitable for pork HTP, which promoted the practical biogas yield because of the synergistic effect between proteins and lipids. Ammonia inhibition was reduced by the addition of hydrochar to the CSTR during co-digestion of SR and LP, maximum ammonia concentration tolerated by methanogens increased from 2.68 to 3.38 g/L. This improved total biogas yield and degradation rate of substrates, reaching values of 28.62 and 36.06%, respectively. The acetate content in volatile fatty acids (VFA) may be used as an index that reflects the degree of methanogenesis of the system. The results of the present work may also provide guidance for the digestion of feedstock with high protein and lipid content.

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Disintegration of Wastewater Activated Sludge (WAS) for Improved Biogas Production: A Mini Review

10.20944/preprints201811.0441.v1 ◽

2018 ◽

Author(s):

Stanisław Wacławek ◽

Klaudiusz Grübel ◽

Daniele Silvestri ◽

Vinod V.T. Padil ◽

Maria Ząbkowska-Wacławek ◽

...

Keyword(s):

Activated Sludge ◽

Sustainable Management ◽

Fermentation Process ◽

Wastewater Treatment Plants ◽

Biogas Production ◽

Waste Activated Sludge ◽

Rapid Urbanization ◽

Biogas Yield ◽

Digestion Process ◽

Physical And Chemical

Due to rapid urbanization, the quantity of wastewater treatment plants (WWTP) has increased, and with it the amount of waste generated by them. Sustainable management of this waste can lead to the creation of energy-rich biogas through the fermentation process. This review presents recent advances in the anaerobic digestion process resulting in greater biogas production. Disintegration techniques for enhancing waste activated sludge fermentation can be generally partitioned into biological, physical and chemical, each of which are covered in this review. These disintegration techniques were compared mainly in terms of their biogas yield. It was found that ultrasonic and microwave disintegration provides the highest biogas yield (>500%); however, they are also the most energy demanding (>10,000 kJ kg-1 total solids).

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