Anaerobic Digestion Characteristics and Key Microorganisms Associated With Low-Temperature Rapeseed Cake and Sheep Manure Fermentation

Abstract Qinghai rural household biogas digesters were used to evaluate fermentation characteristics, including gas production and key microbial community changes, associated with low-temperature (15.2-17.8℃) mixed rapeseed cake and sheep manure anaerobic fermentations across 40 days using seven different ratios of material. Different raw material ratios resulted in significantly different effects on biogas yields and microbial community compositions. When the ratio of sheep manure to rapeseed cake was 1:2, the highest level of cumulative gas production was observed (122.92 m3·t−1). Firmicutes, Proteobacteria, Bacteroidetes, and Actinobacteria were the dominant bacterial phyla among the 29 digester samples (total relative abundances > 79.23%), followed by Synergistetes (4.09%-10.7%). Lactobacillus was the most abundant genus in the biogas digesters with high rapeseed cake contents (average relative abundances: 14.68%), while Peptoniphilus exhibited higher abundances (12.69%) in the mixed fermentation digester treatments. In addition, unclassified Synergistaceae abundances (6.64%) were positively associated with biogas production variation among treatments. Bacteroides (5.74%) and Pseudomonas (5.24%) both accounted for larger proportions of communities in the digesters that used more sheep manure. Methanomicrobiales (66.55%) was the most dominant archaeal group among digesters, with Methanogenium (41.82%) and Methanoculleus (16.55%) representing the main gas-producing archaeal genera; they were more abundant in biogas digesters with higher sheep manure contents and higher rapeseed cake contents, respectively. Regardless of the raw material ratios, Methanoculleus exhibited the highest abundances on the 4th day of fermentation. VFAs and pH were the main factors associated with differences in microbial communities among the 29 samples. Specifically, VFA concentrations were positively correlated with Lactobacillus and Methanoculleus abundances, while pH was positively correlated with Bacteroides, Pseudomonas, Methanobrevibacter, and Methanobacterium abundances.

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A Study on Dry Anaerobic Fermentation Technology of Pineapple Leaf Residue

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.236-238.178 ◽

2011 ◽

Vol 236-238 ◽

pp. 178-182

Author(s):

Yi Guo Deng ◽

Jin Li Wang ◽

Jing Jiao ◽

Yong Zheng ◽

Gang Wang ◽

...

Keyword(s):

Anaerobic Fermentation ◽

Biogas Production ◽

Orthogonal Experiment ◽

Gas Production ◽

Inoculum Size ◽

Solid Content ◽

Raw Material ◽

Biogas Yield ◽

Fermentation Temperature ◽

Leaf Residue

A self-designed constant temperature fermenter was manufactured and used for this study. Dry anaerobic fermentation experiments were conducted with sugarcane leaf residue as raw material. With the C/N ratio being 25:1, various total solids concentrations (TS), inoculum sizes and fermentation temperatures were selected to study biogas production characteristics. The experiment results showed that biogas yield increased rapidly during the initial stage of reaction, decreased quickly after reaching the peak, and the decrease slowed down at some level. Orthogonal experiment results showed that both fermentation temperature and solids concentration showed significant effects on gas production yield. Fermentation temperature showed the most significant effect, while the effect of inoculum size was not significant on gas yield. The optimum fermentation performance was obtained at 20% solid content, 35°C fermentation temperature, and 30% inoculum size.

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Sertanejo biodigestor: a social technology, an alternative source of energy

Revista Brasileira de Ciências Ambientais (Online) ◽

10.5327/z21769478987 ◽

2021 ◽

Vol 56 (4) ◽

pp. 630-642

Author(s):

Reginaldo Alves De Souza ◽

Marília Regina Costa Castro Lyra ◽

Renata Maria Caminha M. de O. Carvalho ◽

José Coelho de Araújo Filho

Keyword(s):

Low Income ◽

Alternative Energy ◽

Biogas Production ◽

Gas Production ◽

Raw Material ◽

Social Technology ◽

Liquefied Petroleum Gas ◽

Material Source ◽

Alternative Source ◽

Farming Families

The use of biogas as an alternative to using liquefied petroleum gas (LPG) for cooking food in the context of family farming is something recent and has ample room for growth. The aim of this study was to evaluate the use of the Sertanejo biodigester by farming families as a social technology for cooking gas production, as well as an alternative energy source. It also aimed to identify elements which contribute to disseminating this technology as an alternative to the use of firewood, charcoal and LPG. Quali-quantitative approaches were used following the exploratory method, with interviews and non-probabilistic sampling. A population with 132 units of biodigesters in the Agreste mesoregion of the State of Pernambuco was considered, with 83 interviews being collected. The results indicated that the Sertanejo biodigester social technology provides an increase in the income of farming families, avoids the use of firewood and charcoal for cooking food and produces biofertilizer for crops. They also showed that its non-continuous use or deactivation is related to a lack of raw material and the need for maintenance. Given this scenario, its implementation must consider the availability of a raw material source in the production unit and the potential for biogas production from the existing herd and consumption demand. It is recommended to strengthen arguments of economic and environmental impact for low-income families to disseminate this technology; to encourage the use of biogas associated with other activities in the production system; and to incorporate biodigestor social technology in rural credit financing lines.

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Application of Modified Gompertz Model to Study on Biogas production from middle temperature co-digestion of pig manure and dead pigs

E3S Web of Conferences ◽

10.1051/e3sconf/201911803022 ◽

2019 ◽

Vol 118 ◽

pp. 03022

Author(s):

Hongguang Zhu ◽

Jing Yang ◽

Cheng Xiaowei

Keyword(s):

Anaerobic Digestion ◽

Degradation Rate ◽

Biogas Production ◽

Raw Materials ◽

Gompertz Model ◽

Gas Production ◽

Raw Material ◽

Pig Manure ◽

Middle Temperature ◽

Modified Gompertz Model

The dead pig is an organic waste rich in oil and protein, and is an ideal anaerobic digestion raw material. This study based on single factor ANOVA and Modified Gompertz model. It investigated the effects of the ratio of dead pigs on biogas production by middle temperature co-digestion of pig manure and dead pigs. And the biogas production potential was determined. The results showed that there was no significant correlation between the ratio of dead pigs and the biogas production. The ratio would significantly affect the average methane content and degradation rate. When the addition ratio was in the range of 3 to 15%, the biogas production was between 191.39 and 202.44 (L/kg VS). The average contents of methane were 50.67%, 50.35%, 41.83%, 45.53% and 44.57%, respectively. The time required to reach 80% of the biogas production was 28, 34, 36, 65 and 63 days, respectively. The degradation rate of the raw materials was generally decreased with the increase of the addition ratio. The results of Modified Gompertz model fitting showed that the mixed raw materials had a fully anaerobic digestion with high utilization rate and short hysteresis in the range of 0 ~ 9%. Therefore, a hydraulic retention time (HRT) of 30 days and the addition ratio was in the range of 0 to 6% could be recommended for a continuous digester. It could get a better gas production and higher raw material utilization.

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GREEN ALGAE Ulva sp. AS RAW MATERIAL FOR BIOGAS PRODUCTION

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.28930/jitkt.v7i1.9806 ◽

2015 ◽

Vol 7 (1) ◽

Author(s):

Tri Dian Oktiana ◽

Joko Santoso ◽

Mujizat Kawaroe

Keyword(s):

Gas Flow ◽

Loading Rate ◽

Biogas Production ◽

High Growth ◽

High Growth Rate ◽

Gas Production ◽

Raw Material ◽

Organic Loading Rate ◽

Organic Loading ◽

Edible Seaweed

Ulva sp. is a non edible seaweed and posses a high growth rate. Therefore, this species is potential to be developed as a raw material for biogas production. One important factor on the biogas production is to determine organic loading rate (OLR). The aim of this study was to determine the potential of Ulva sp. as a raw material for biogas and to find out the optimum loading rate in the process of biogas production. Biogas production was carried out in the digester with a capacity of 22 l that was made of fiber and equipped with a manual stirrer and gas flow meter to measure gas production. Parameters analised were pH, COD, TSS, VSS, and gas composition. Organic loading rates used in this study were 0.5, 1, 1.5, and 2 kg COD.m-3.day-1. The results showed that the optimum loading rate was 1.5 kg COD.m-3.day-1. In the loading rate of 1.5 kg COD.m-3.day-1, we obtained the highest biogas production rate of 12.14 l/day with methane content of 42.96%, average COD removal of 51.97%, and methane production of 0.33 l/g COD. Keywords: anaerobic, biogas, COD, loading, methane, Ulva sp.

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Experimental Study on Potential of Biogas Fermentation with Lily Straw

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.608-609.396 ◽

2012 ◽

Vol 608-609 ◽

pp. 396-401

Author(s):

Hong Yang ◽

Wu Di Zhang ◽

Xing Ling Zhao ◽

Jing Liu ◽

Yu Bao Chen ◽

...

Keyword(s):

Experimental Study ◽

Anaerobic Digestion ◽

Ph Value ◽

Biogas Production ◽

Gas Production ◽

The Other ◽

Raw Material ◽

Production Potential ◽

Biogas Yield ◽

The Third

This paper studies on the biogas production yield of which use the lily straw as raw material and the fermentation is batch by batch at 30°C. In the third day of fermentation, fermented liquid became acidic. But it can be back to normal with the action of the anaerobic microbe. Its biogas yield is higher than the other group to adjust pH value. So gas production potential of the lily straw is 475ml/gTS and 573ml/gVS with 31 days of anaerobic digestion. The volumetric biogas production rate reaches 0.19ml/ml/d.

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Anaerobic Co-Digestion of Oil Sludge with Corn Stover for Efficient Biogas Production

Sustainability ◽

10.3390/su12051861 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1861

Author(s):

Qian Yang ◽

Chenxi Zhang ◽

Lei Li ◽

Weijie Xu

Keyword(s):

Corn Stover ◽

Production Efficiency ◽

Biogas Production ◽

Gas Production ◽

Production Performance ◽

Raw Material ◽

Oil Sludge ◽

Smelting Process ◽

Fundamental Parameter ◽

Production Volume

The feasibility of anaerobic co-digestion for the utilization of oil sludge was verified using corn stover, to assess the influence of different raw material ratios and inoculum volumes on the properties of the generated gas. The anaerobic co-digestion method is a novel treatment technology, which may help to solve the problem of pollution by hazardous waste oil sand from the oil exploitation and smelting process. Results showed that single-oil sludge was not suitable for gas production as a digestive substrate due to the lack of organic materials and possible hazardous materials. With the increase in the quality of exogenous organic matter (corn stover), the cumulative gas production volume was proportional to the amount of corn stover material added. It was established that when the mass ratio of corn stover to oil sludge was 4:1, the gas production performance was optimal, with a cumulative gas yield of 1222.5 mL using an inoculum volume of 30 mL. The results of this study provide a fundamental parameter baseline for the treatment of oil sludge and the improvement of gas production efficiency.

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GREEN ALGAE Ulva sp. AS RAW MATERIAL FOR BIOGAS PRODUCTION

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v7i1.9806 ◽

2015 ◽

Vol 7 (1) ◽

Author(s):

Tri Dian Oktiana ◽

Joko Santoso ◽

Mujizat Kawaroe

Keyword(s):

Gas Flow ◽

Loading Rate ◽

Biogas Production ◽

High Growth ◽

High Growth Rate ◽

Gas Production ◽

Raw Material ◽

Organic Loading Rate ◽

Organic Loading ◽

Edible Seaweed

Ulva sp. is a non edible seaweed and posses a high growth rate. Therefore, this species is potential to be developed as a raw material for biogas production. One important factor on the biogas production is to determine organic loading rate (OLR). The aim of this study was to determine the potential of Ulva sp. as a raw material for biogas and to find out the optimum loading rate in the process of biogas production. Biogas production was carried out in the digester with a capacity of 22 l that was made of fiber and equipped with a manual stirrer and gas flow meter to measure gas production. Parameters analised were pH, COD, TSS, VSS, and gas composition. Organic loading rates used in this study were 0.5, 1, 1.5, and 2 kg COD.m-3.day-1. The results showed that the optimum loading rate was 1.5 kg COD.m-3.day-1. In the loading rate of 1.5 kg COD.m-3.day-1, we obtained the highest biogas production rate of 12.14 l/day with methane content of 42.96%, average COD removal of 51.97%, and methane production of 0.33 l/g COD. Keywords: anaerobic, biogas, COD, loading, methane, Ulva sp.

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Preparation and application of carbon and hollow TiO2 microspheres by microwave heating at a low temperature

e-Polymers ◽

10.1515/epoly-2021-0014 ◽

2021 ◽

Vol 21 (1) ◽

pp. 200-209

Author(s):

Caiyun Zhang ◽

Chunhong Li ◽

Bolin Ji ◽

Zhaohui Jiang

Keyword(s):

Low Temperature ◽

Microwave Heating ◽

Raw Material ◽

Carbon Microspheres ◽

Microwave Assisted ◽

The Core ◽

Good Crystallinity ◽

Carbon Core ◽

Microwave Assisted Method ◽

Uniform Particle Size

Abstract A fast, simple, and energy-saving microwave-assisted approach was successfully developed to prepare carbon microspheres. The carbon microspheres with a uniform particle size and good dispersity were prepared using glucose as the raw material and HCl as the dehydrating agent at low temperature (90°C) in an open system with the assistance of microwave heating. The carbon microspheres were characterized by elemental analysis, XRD, SEM, FTIR, TG, and Raman. The results showed that the carbon microspheres prepared under the condition of 18.5% (v/v) HCl and heating for 30 min by microwave had a narrow size distribution. The core–shell structure of the carbon core and TiO2 shell was prepared with (NH4)2TiF6, H3BO3 using the microwave-assisted method. The hollow TiO2 microspheres with good crystallinity and high photocatalytic properties were successfully prepared by sacrificing the carbon microspheres.

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Experimental Parameter Study on Synthesis Gas Production by Steam-Oxygen Fluidized Bed Gasification of Sewage Sludge

Applied Sciences ◽

10.3390/app11020579 ◽

2021 ◽

Vol 11 (2) ◽

pp. 579

Author(s):

Max Schmid ◽

Selina Hafner ◽

Günter Scheffknecht

Keyword(s):

Sewage Sludge ◽

Fluidized Bed ◽

Experimental Parameter ◽

Space Velocity ◽

Phosphate Fertilizer ◽

Gas Production ◽

Raw Material ◽

Parameter Study ◽

Syngas Production ◽

Fuels And Chemicals

The conversion of biogenic residues to fuels and chemicals via gasification and synthesis processes is a promising pathway to replace fossil carbon. In this study, the focus is set on sewage sludge gasification for syngas production. Experiments were carried out in a 20 kW fuel input bubbling fluidized bed facility with steam and oxygen as gasification agent. In-situ produced sewage sludge ash was used as bed material. The sensitivity of the key operation parameters gasifier temperature, oxygen ratio, steam to carbon ratio, and the space velocity on the syngas composition (H2, CO, CO2, CH4, CxHy, H2S, COS, NH3, and tars) was determined. The results show that the produced syngas has high H2 and CO concentrations of up to 0.37 m3 m−3 and 0.18 m3 m−3, respectively, and is thus suitable for synthesis of fuels and chemicals. By adjusting the steam to carbon ratio, the syngas’ H2 to CO ratio can be purposely tailored by the water gas shift reaction for various synthesis products, e.g., synthetic natural gas (H2/CO = 3) or Fischer–Tropsch products (H2/CO = 2). Also, the composition and yields of fly ash and bed ash are presented. Through the gasification process, the cadmium and mercury contents of the bed ash were drastically reduced. The ash is suitable as secondary raw material for phosphorous or phosphate fertilizer production. Overall, a broad database was generated that can be used for process simulation and process design.

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Effects of brewers’ spent grain protein hydrolysates on gas production, ruminal fermentation characteristics, microbial protein synthesis and microbial community in an artificial rumen fed a high grain diet

Journal of Animal Science and Biotechnology ◽

10.1186/s40104-020-00531-5 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Tao Ran ◽

Long Jin ◽

Ranithri Abeynayake ◽

Atef Mohamed Saleem ◽

Xiumin Zhang ◽

...

Keyword(s):

Protein Synthesis ◽

Microbial Community ◽

Antioxidant Properties ◽

Value Added ◽

Gas Production ◽

Protein Hydrolysates ◽

Ruminal Fermentation ◽

Microbial Protein ◽

Microbial Protein Synthesis ◽

Spent Grain

Abstract Background Brewers’ spent grain (BSG) typically contains 20% – 29% crude protein (CP) with high concentrations of glutamine, proline and hydrophobic and non-polar amino acid, making it an ideal material for producing value-added products like bioactive peptides which have antioxidant properties. For this study, protein was extracted from BSG, hydrolyzed with 1% alcalase and flavourzyme, with the generated protein hydrolysates (AlcH and FlaH) showing antioxidant activities. This study evaluated the effects of AlcH and FlaH on gas production, ruminal fermentation characteristics, nutrient disappearance, microbial protein synthesis and microbial community using an artificial rumen system (RUSITEC) fed a high-grain diet. Results As compared to the control of grain only, supplementation of FlaH decreased (P < 0.01) disappearances of dry matter (DM), organic matter (OM), CP and starch, without affecting fibre disappearances; while AlcH had no effect on nutrient disappearance. Neither AlcH nor FlaH affected gas production or VFA profiles, however they increased (P < 0.01) NH3-N and decreased (P < 0.01) H2 production. Supplementation of FlaH decreased (P < 0.01) the percentage of CH4 in total gas and dissolved-CH4 (dCH4) in dissolved gas. Addition of monensin reduced (P < 0.01) disappearance of nutrients, improved fermentation efficiency and reduced CH4 and H2 emissions. Total microbial nitrogen production was decreased (P < 0.05) but the proportion of feed particle associated (FPA) bacteria was increased with FlaH and monensin supplementation. Numbers of OTUs and Shannon diversity indices of FPA microbial community were unaffected by AlcH and FlaH; whereas both indices were reduced (P < 0.05) by monensin. Taxonomic analysis revealed no effect of AlcH and FlaH on the relative abundance (RA) of bacteria at phylum level, whereas monensin reduced (P < 0.05) the RA of Firmicutes and Bacteroidetes and enhanced Proteobacteria. Supplementation of FlaH enhanced (P < 0.05) the RA of genus Prevotella, reduced Selenomonas, Shuttleworthia, Bifidobacterium and Dialister as compared to control; monensin reduced (P < 0.05) RA of genus Prevotella but enhaced Succinivibrio. Conclusions The supplementation of FlaH in high-grain diets may potentially protect CP and starch from ruminal degradation, without adversely affecting fibre degradation and VFA profiles. It also showed promising effects on reducing CH4 production by suppressing H2 production. Protein enzymatic hydrolysates from BSG using flavourzyme showed potential application to high value-added bio-products.

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