Abstract:
A mathematical model for anaerobic hybrid reactor has been developed. In1999, Jakapong has developed this model. The previous model reasonably wellestimated the reactor variables. However, the model could not predict the failure ofthe reactor when organic shock loading was applied. This may be due to the overprediction of biomass concentration in the reactor. Consequently, this modelimproved the previous model by focusing on the part of the biomass estimatlon. Thebiomass parameters affecting on the biomass estimation have been studied. Thestudy results showed that the biomass parameters (kt and ktt) are not constant valuesbut they are the functions of HRT and reactor configuration. The relationshipbetween biomass parameters, HRT, and reactor configuration are kt = [(0.21HRT -0.28)(SV/PV)] and ktt, = [3.20 HRT(SV/PV) - 5.00(PV/SV)].The model was validated with 3 experiments (from the Biogas TechnologyResearch Group of KMUTT) that operated in the different reactor configurations.The height fractions of sludge zone to packed zone in reactor numbers 1, 2, and 3 are5:3, 4:4, and 3:5, respectively. The simulation results were compared in TVA, COD,biomass, reactor pH, and methane gas production rate. The agreement of each reactorbetween model estimation and experimental values was quite good and much betterthan that of the previous model. Moreover, for the estimation of reactor efficiency,the most efficient reactors are reactor number 3, reactor number 2, and reactornumber 1, respectively.