Biogas production from anaerobic codigestion of cowdung and elephant grass (Pennisetum Purpureum) using batch digester

2nd International Conference on Biomass: Toward Sustainable Biomass Utilization for Industrial and Energy Applications

生物科学;工业技术;能源学

Haryanto, Agus^1 ; Hasanudin, Udin^2 ; Afrian, Chandra^1 ; Zulkarnaen, Iskandar^1

Agricultural Engineering Department, Faculty of Agriculture, University of Lampung, Soemantri Brojonegoro Road #1, Bandar Lampung, Indonesia^1

Agricultural Product Technology Department, Faculty of Agriculture, University of Lampung, Soemantri Brojonegoro Road #1, Bandar Lampung, Indonesia^2

关键词: Anaerobic co-digestion;    Biogas composition;    Control treatments;    Daily temperatures;    Digestion process;    Mechanical pre-treatment;    Pennisetum purpureum;    Substrate composition;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/141/1/012011/pdf
DOI  :  10.1088/1755-1315/141/1/012011

来源: IOP

【 摘 要 】

This study aimed at determining biogas production from codigestion of Elephant grass and cowdung using batch digester. Fresh grass was manually chopped with a maximum length of 3 cm. Chopped grass (25 kg) was perfectly mixed with fresh cowdung (25 kg). The mixture was introduced into a 220-liter batch drum digester. The substrate was diluted with water at different rates (P1 = 50 L, P2 = 75 L, and P3 = 100 L) and was stirred thoroughly. Six digesters were prepared as duplicate for each treatment. Two other digesters containing only 25 kg cowdung diluted with 25 L water were also provided as control treatment (P0). The digesters were air tightly sealed for 70 days. Observation was conducted on daily temperature, substrate pH (initial and final), TS and VS content, biogas yield and biogas composition. Results showed that final pH of grass containing substrate was in the acidic range, namely 4.50, 4.62, 6.82, whereas that of control (P0) was normal with pH of 7.30. Digester with substrate composition 25:25:100 (cowdung:grass:water) produced the highest biogas total (524.3 L). Biogas yield of codigestion, however, was much lower as compared to that of control, namely 7.35, 16.75, and 111.72 L/kg VSrrespectively for treatment P1, P2, P3. with dilution rate of 50, 75, and 100 L. Biogas produced from control digester had methane content of 53.88%. In contrast, biogas resulted from all treatments contained low methane (the highest was 31.37%). Methane yield of 39.3 L/kg TS removal was achieved from digester with dilution 100 L (P3). Mechanical pretreatment is suggested to break Elephant grass down into smaller particles prior to introducing it into the digestion process.