Batch Mesophilic Anaerobic Co-digestion of Spent Goat Batch Mesophilic Anaerobic Co-digestion of Spent Goat Straw Bedding and Goat Cheese Whey: Comparison with the Mono-digestion of the Two Sole Substrates

Spent livestock bedding is a valuable resource for the production of green energy (methane) in rural areas. Comparison and evaluation of batch anaerobic digestion and co-digestion of different mixtures of goat straw bedding (SGSB) and goat cheese whey were carried out. Biochemical methane potential...

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Detalles Bibliográficos
Autores: Fernández Rodríguez, María José, Puntano, N. F., Mancilla Leytón, Juan Manuel, Borja, Rafael
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2021
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/139577
Acceso en línea:https://hdl.handle.net/11441/139577
https://doi.org/10.1016/j.jenvman.2020.111733
Access Level:acceso abierto
Palabra clave:Anaerobic co-digestion
Cheese whey
Methane yield
Process kinetics
Spent goat straw bedding
Two-substrate model
Descripción
Sumario:Spent livestock bedding is a valuable resource for the production of green energy (methane) in rural areas. Comparison and evaluation of batch anaerobic digestion and co-digestion of different mixtures of goat straw bedding (SGSB) and goat cheese whey were carried out. Biochemical methane potential (BMP) tests of the 100% SGSB, 95% SGSB-5% whey, 90% SGSB-10% whey, 85% SGSB-15% whey and 100% whey were found to be 423 ± 7, 354 ± 9, 371 ± 2, 293 ± 1, 274 ± 2 mL CH4 g−1 VS. Two different kinetic models were evaluated. The logistic model revealed a decrease in the maximum methane production rate (Rm) from 34.7 ± 1.5 to 14.1 ± 0.9 mL CH4 g−1 VS·d−1 when the percentage of whey in the mixture increased from 0 to 15% as a consequence of the increased ammonia released during the co-digestion of increased concentrations of whey. The lowest value for the maximum methane production predicted by the model (P) was found for 100% whey (274 ± 10 mL CH4 g−1 VS). A two-substrate model was applied to describe the evident existence of rapid and slowly degradable material. Regarding the hydrolysis kinetic constants predicted by this model, considerable increases in the rapid biodegradation stage (krapid) were observed when comparing to the values found for the slow (kslow) biodegradation stage in all the cases tested. The increases between both constants rose from 5 to 42% when the percentage of whey increased.