Effects of Organic Nitrogen and Carbon Supplementation on Biomethanation of Rice Bran

Abstract

The effects of organic nitrogen, sucrose and starch on the bio-methanation of rice bran were investigated using digesters of 1-litre capacity operated at ambient temperature (30 – 32oC) and pH of 7 for 20 days. Rice bran and organic nitrogen supplement were varied at ratios 2:1, 3:1, 4:1 and 5:1, while 20g of sucrose and 20 g of starch were added to rice bran as supplements. Fresh strained cow rumen liquor was used as inoculum. There was no significant difference (P<0.05) between non-supplemented and sucrose supplemented feedstock. Starch supplemented feedstock produced more biogas than the sucrose supplemented and the non-supplemented feedstock (P>0.05). Varying the organic nitrogen had no significant effect on the biogas yield (P<0.05).

Batch Mode Biomethane Production from Anaerobic Digestion of Palm Oil Mill Effluent (POME) with Cassava Peels and Cabbage Waste

“…The methanogenic bacteria use up the nitrogen content of the substrate to meet their protein needs when the C: N ratio is very high resulting to imbalance in C: N ratio which causes low biogas production. On the other hand if the C: N ratio is low, excess nitrogen will be released during microbial metabolism and this piles up in the form ammonia which increases the pH value of the feedstock above 8.5 and resultant effect being the exertion of toxic substances on the methanogens causing low biogas yield [34].…”