Biomethane production from vinasse in upflow anaerobic sludge blanket reactors inoculated with granular sludge.
The main objective of this study was to evaluate the anaerobic conversion of vinasse into biomethane with gradual increase in organic loading rate (OLR) in two upflow anaerobic sludge blanket (UASB) reactors, R1 and R2, with volumes of 40.5 and 21.5L in the mesophilic temperature range. The UASB reactors were operated for 230 days with a hydraulic detection time (HDT) of 2.8d (R1) and 2.8-1.8d (R2). The OLR values applied in the reactors were 0.2-7.5gtotalCOD (Ld)(-1) in R1 and 0.2-11.5gtotalCOD (Ld)(-1) in R2. The average total chemical oxygen demand (totalCOD) removal efficiencies ranged from 49% to 82% and the average conversion efficiencies of the removed totalCOD into methane were 48-58% in R1 and 39-65% in R2. The effluent recirculation was used for an OLR above 6gtotalCOD (Ld)(-1) in R1 and 8gtotalCOD (Ld)(-1) in R2 and was able to maintain the pH of the influent in R1 and R2 in the range from 6.5 to 6.8. However, this caused a decrease for 53-39% in the conversion efficiency of the removed totalCOD into methane in R2 because of the increase in the recalcitrant COD in the influent. The largest methane yield values were 0.181 and 0.185 (L) CH4 (gtotalCOD removed)(-1) in R1 and R2, respectively. These values were attained after 140 days of operation with an OLR of 5.0-7.5gtotalCOD (Ld)(-1) and totalCOD removal efficiencies around 70 and 80%.
Post-Graduate Program in Agricultural and Livestock Microbiology, Faculty of Agricultural and Veterinary Sciences, Univ Estadual Paulista, Campus of Jaboticabal, Jaboticabal, SP, Brazil.
Valciney Gomes de
VG
Barros
Laboratory of Environmental Sanitation, Department of Rural Engineering, Faculty of Agricultural and Veterinary Sciences, Univ Estadual Paulista, Campus of Jaboticabal, Jaboticabal, SP, Brazil; Faculty of Technology Jaboticabal, Jaboticabal, SP, Brazil.
Rose Maria
RM
Duda
Post-Graduate Program in Agricultural and Livestock Microbiology, Faculty of Agricultural and Veterinary Sciences, Univ Estadual Paulista, Campus of Jaboticabal, Jaboticabal, SP, Brazil; Laboratory of Environmental Sanitation, Department of Rural Engineering, Faculty of Agricultural and Veterinary Sciences, Univ Estadual Paulista, Campus of Jaboticabal, Jaboticabal, SP, Brazil. Electronic address: raoder@fcav.unesp.br.
Roberto Alves de
RA
Oliveira
D000693:Anaerobiosis; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000096:biosynthesis*; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D012722:Sewage / Q000382:microbiology*; D055549:Volatile Organic Compounds
D012722:Sewage; D055549:Volatile Organic Compounds; D010758:Phosphorus; D009584:Nitrogen; D008697:Methane
Biogas; Mesophilic anaerobic treatment; Methane; Organic loading rate; Startup