Biochemical Methane Potential (BMP) of Cattle Manure, Chicken Manure, Rice Straw, and Hornwort in Mesophilic Mono-digestion

Biochemical Methane Potential (BMP) assay was used to investigate the potential of methane production from agricultural wastes and weed. The objective of the study is to investigate the methane production potential from cattle manure, chicken manure, rice straw, and hornwort (Ceratophyllum demersum). The result of the study can be used to choose the most suitable substrate for renewable energy generation as well as to prioritize waste treatment to reduce Greenhouse Gases (GHGs) emission from waste. Cattle manure (CWM), chicken manure (CHM), rice straw (RSW), and hornwort (HNW) were used as substrates for batch anaerobic digestion under mesophilic condition at 35 °C using 500 mL glass bottles and working volume of 350 mL with substrate at inoculum to substrate ratio (ISR) of 1:1 based on Volatile Solids (VS) weight (g VS). Parameters observed including biogas production, biogas composition, methane production, and specific methane yield. Results showed that among four substrates, RSW had the highest total biogas production of 3773.33 mL, while the lowest was CHM with 1443.00 mL. In term of the biogas composition, HNW had the highest methane proportion of 66.68% among all substrates used, while RSW had the lowest proportion (62.50%). Furthermore, the highest methane production was from RSW at 2135.52 mL and the lowest was from CHM at 736.28 mL. In addition, the highest specific methane yield was obtained from RSW with a total of 331.99 NmL CH4/g VS, while CHM had the lowest yield with 114.55 NmL CH4/g VS. From results of the study, RSW was found to be a very promising substrate for a potential source of renewable energy with a high methane yield

Biogas Production from Biomass Residues of Palm Oil Mill by Solid State Anaerobic Digestion

AbstractSolid state anaerobic digestion is a safe and environmental friendly technology to dispose solid wastes, could produce methane and reduce the volume of wastes. Three biomass residues from palm oil mill plant including empty fruit bunches (EFB), palm press fiber (PPF) and decanter cake (DC) were evaluated for methane production by solid state anaerobic digestion. Oil palm biomass was mixed with inoculum at F/I ratio of 2:1, 3:1, 4:1, 5:1 and 6:1 based on the volatile solid (VS). Results show that among the five F/I ratios tested, the F/I ratio of 2:1 gave the highest methane yield and methane production for all biomass residues. The highest cumulative methane production of 2180 mLCH4 was obtained from EFB followed by PPF (1964mL CH4) and DC (1827mL CH4) at F:I ratio of 2:1. The highest methane yield of 144mL CH4/gVS was obtained from EFB followed by PPB (140mL CH4/gVS) and DC (130mL CH4/gVS) at F/I ratios of 2:1. Methane production from EFB, PPF and DC by SS-AD was 55, 47 and 41 m 3 CH4/ton, respectively. These results collectively suggested that EFB could be a promising substrate for methane production by SS-A

Effects of volatile fatty acids in biohydrogen effluent on biohythane production from palm oil mill effluent under thermophilic condition

Background: Biohydrogen effluent contains a high concentration of volatile fatty acid (VFA)mainly as butyric, acetic, lactic and propionic acids. The presence of various VFAs (mixture VFAs) and their cooperative effects on two-stage biohythane production need to be further studied. The effect of VFA concentrations in biohydrogen effluent of palm oil mill effluent (POME) on methane yield in methane stage of biohythane production was investigated. Results: Themethane yield obtained in low VFA loading (0.9 and 1.8 g/L) was 15\u201320% times greater than that of high VFA loading (3.6 and 4.7 g/L). Butyric acid at high concentrations (8 g/L) has the individual significantly negative effect the methane production process (P < 0.05). Lactic, acetic and butyric acid mixed with propionic acid at a concentration higher than 0.5 g/L has an interaction significantly negative effect on the methanogenesis process (P < 0.05). Inhibition condition had a negative effect on both bacteria and archaea with inhibited on Geobacillus sp., Thermoanaerobacterium thermosaccharolyticum , Methanoculleus thermophilus and Methanothermobacter delfuvii resulting in low methane yield. Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production