title: Mesophilic methane fermentation of chicken manure at a wide range of ammonia concentration: stability, inhibition and recovery.
abstract: A 12L mesophilic CSTR of chicken manure fermentation was operated for 400 days to evaluate process stability, inhibition occurrence and the recovery behavior suffering TAN concentrations from 2000 mg/L to 16,000 mg/L. A biogas production of 0.35-0.4 L/gVS(in) and a COD conversion of 68% were achieved when TAN concentration was lower than 5000 mg/L. Ammonia inhibition occurred due to the addition of NH4HCO3 to the substrate. The biogas and COD conversion decreased to 0.3 L/gVS(in) and 20% at TAN 10,000 mg/L and was totally suppressed at TAN 16,000 mg/L. Carbohydrate and protein conversion decreased by 33% and 77% after inhibition. After extreme inhibition, the reactor was diluted and washed, reducing TAN and FA to 4000 mg/L and 300 mg/L respectively, and the recovered biogas production was 0.5 L/gVS(in). The extended Monod model manifested the different sensitivities of hydrolysis, acidogenesis and methanogenesis to inhibition. VFA accumulation accompanied an increase in ammonia and exerted a toxic on microorganism.
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, Aoba-ku, Sendai, Miyagi, Japan.
authors.forename: Qigui
authors.initials: Q
authors.lastname: Niu
authors.forename: Wei
authors.initials: W
authors.lastname: Qiao
authors.forename: Hong
authors.initials: H
authors.lastname: Qiang
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Hojo
authors.forename: Yu-You
authors.initials: YY
authors.lastname: Li
mesh_terms: D000641:Ammonia; D000818:Animals; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D002645:Chickens; D005285:Fermentation; D008372:Manure; D008697:Methane / Q000378:metabolism*
chemical_list: D008372:Manure; D000641:Ammonia; D008697:Methane