Biogas production rate analysis of anaerobic digestion with thermal hydrolysis pretreatment in a semi- continuous bench-scale reactor

In this paper, cow manure fluid was used as inoculums to investigate biogas production rate from anaerobic digestion of cassava peel at mesophilic temperature (280C). The anaerobic experiment was conducted using six batch digesters (D1, D2, D3, D4, D5 and D6) each of 20L capacity for 40-day hydraulic retention. Each digester, was loaded with 5kg of cassava peel (CP) and 0%, 10%, 20%, 30%, 40% and 50% of inoculum to CP. Hashimoto model was used to obtain the digestion kinetic parameters. The results of the study showed that inoculums influenced the rate of biogas production, showing variations in biogas production, correlation coefficient (R2) and in first-order decay constant (k). The average cumulative biogas production was in the range of ~2358 to 4010ml/kgVS for 10% to 50% inoculum. The R2 and k for D1 was 0.959 and 0.359 D1 (without inoculum), 0.990 and 0.371 for D2 (10% inoculum) and 0.991 and 0.371 for D3 (20% inoculum), 0.951 and 0.356 for D4 (30% inoculum), 0.992 and 0.372 for D5 (40% inoculum), and 0.990 and 0.371 was obtained for D6 loaded with 50% inoculum. Despite variation in biogas yields from different inoculums, biogas production obtained from anaerobic digesters loaded with inoculums were still lower compared with that without inoculum.

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Improved Anaerobic Digestion by a Thermal chemical Pretreatment the Kinetic of Biogas Production Rate from Sewage Sludge in Batch mode

CBEMS-18,DMCCIA-18,EHSSM-18,BLEIS-18,ICLTET-18 March 21-23, 2018 Istanbul (Turkey) ◽

10.17758/dirpub1.c0318117 ◽

2018 ◽

Keyword(s):

Anaerobic Digestion ◽

Sewage Sludge ◽

Production Rate ◽

Biogas Production ◽

Chemical Pretreatment ◽

Batch Mode ◽

Biogas Production Rate

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Effects of Pretreatment and Ratio of Solid Sago Waste to Rumen on Biogas Production through Solid-State Anaerobic Digestion

Sustainability ◽

10.3390/su13137491 ◽

2021 ◽

Vol 13 (13) ◽

pp. 7491

Author(s):

Siswo Sumardiono ◽

Gebyar Adisukmo ◽

Muthia Hanif ◽

Budiyono Budiyono ◽

Heri Cahyono

Keyword(s):

Anaerobic Digestion ◽

Production Rate ◽

Microbial Consortium ◽

Biogas Production ◽

Biological Pretreatment ◽

Metabolic Balance ◽

Digestion Process ◽

Potential Source ◽

Sago Waste ◽

Biogas Production Rate

Solid sago waste is a potential source of producing renewable energy in the form of biogas. This study investigated the effects of solid sago waste particle size, biological pretreatment using a microbial consortium of lignocelluloses, pretreatment with NaOH, and the ratio between solid sago waste and cow rumen based on the biogas production rate. Several variations of these conditions were used to achieve this. The anaerobic digestion process was conducted over two months at 30.42 °C ± 0.05 °C, and the biogas production rate was measured every two days. The 1:1 ratio showed better results compared to the 2:1, because it allows the bacteria to achieve metabolic balance. The highest cumulative biogas production (27.91 mL/g TS) was generated when the sago waste underwent milling (±1 mm), pretreatment with 4% NaOH g/g TS, and treatment with microbial consortium 5% v/v at a 1:1 ratio of solid sago waste to the rumen.

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Biogas Production and Heat Transfer Performance of a Multiphase Flow Digester

Energies ◽

10.3390/en12101960 ◽

2019 ◽

Vol 12 (10) ◽

pp. 1960 ◽

Cited By ~ 3

Author(s):

Pei Guo ◽

Jiri Zhou ◽

Rongjiang Ma ◽

Nanyang Yu ◽

Yanping Yuan

Keyword(s):

Heat Transfer ◽

Anaerobic Digestion ◽

Multiphase Flow ◽

Production Rate ◽

Transfer Rate ◽

Field Experiments ◽

Heat Transfer Performance ◽

Biogas Production ◽

Transfer Performance ◽

Biogas Production Rate

Traditional static anaerobic digestion technology presents the disadvantages of a low gas production rate and long digestion cycle, which is not conducive to the treatment of livestock manure. A 12 m3 multiphase flow anaerobic digester (MFD) was developed in this study to improve the biogas production rate and maintain constant temperature digestion during winters. Full-scale field experiments were conducted on the biogas production rate at different temperatures, the dynamic digestion effects, and the dynamic heating digestion effects of the system at Sichuan, China. A comparison of the dynamic and static digestion results of 50 days indicated that the biogas production for the dynamic digestion (DD) group was 115.22 m3 or 127.1% higher than that of the static digestion (SD) group with the same digestion temperature. The results of the heat transfer performance experiment revealed that the heat transfer rate of the system increased significantly, and the temperature of the biogas slurry increased rapidly. The optimization analysis of the system was based on the experimental results of the relationship between the slurry temperature and biogas production rate, and the economical digestion temperature of the system was proposed and calculated. Different insulation materials or insulation thicknesses have an influence on the economical digestion temperature. Additionally, the economical digestion temperature of the system in which the polystyrene insulation layer with a thickness of 90 mm was used, was found to be 27.2 °C. When digestion temperature was 22.3 °C, the energy efficiency ratio (EER) of dynamic anaerobic digestion system is 1. The advantages of MFD are low biogas production unit cost and high heat and mass transfer rate. However, the disadvantage of high operation energy consumption needs further improvement. And additional energy was required when system digestion temperature below 22.3 °C. The proposed MFD and dynamic anaerobic digestion system can play a significant role in using biomass resources and promoting the development of biogas projects.

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Study of thermal hydrolysis as a pretreatment to mesophilic anaerobic digestion of pig slurry

Water Science & Technology ◽

10.2166/wst.2001.0193 ◽

2001 ◽

Vol 44 (4) ◽

pp. 109-116 ◽

Cited By ~ 62

Author(s):

A. Bonmatí ◽

X. Flotats ◽

L. Mateu ◽

E. Campos

Keyword(s):

Anaerobic Digestion ◽

Biogas Production ◽

Limiting Factor ◽

Pig Slurry ◽

Thermal Hydrolysis ◽

Organic Matter Degradation ◽

Thermal Pretreatment ◽

Digestion Process ◽

Degradation Tests ◽

Thermal Phenomena

Feasibility of anaerobic digestion of pig slurry is dependent, among other factors, on the biogas production rate, which is low compared with other organic wastes, and on the profitable uses of surplus thermal energy produced, a limiting factor in warm geographical areas. The objectives of this work are determining whether low temperature thermal pretreatment (<90°C) improves pig slurry anaerobic digestion, and determining whether organic matter degradation during the thermal pretreatment is due to thermal phenomena (80°C) or to enzymatic ones (60°C). The thermal degradation tests showed that hydrolysis occurring during the thermal pretreatment is due to thermal phenomena. The increase in soluble substances were significantly larger at 80°C than at 60°C (both during 3 h). Two types of slurry were used in the batch anaerobic digestion tests. The effect of thermal pretreatment differed with the type of slurry: it was positive with almost non-degraded slurries containing low NH4+-N concentration, and negative (inhibition of the anaerobic digestion process) when using degraded slurries with high NH4+-N content.

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