Evaluation of Biogas Productivity of Agricultural By-Productions Based on Diauxic Growth

Abstract

The objective of this study was to develop minimization method of Diauxic growth lag-phase for Biogas production by agricultural by-productions. Specifically, it was investigated the effects of proximate compositions on the biogas production and degradation rates of agricultural by-productions and developed a new method for minimization of Diauxic growth lag-phase based on proximate composition combination. Experiment were performed using the biogas potential test on the mesophilic condition at organic loading rate(OLR) of 2.5 g VS/L and feed to microorganism ratio(F/M) of 0.5. The agricultural and food by-productions were classified based on proximate compositions (Carbohydrate, Protein, Fat etc).For evaluating the biogas production under Biochemical methane Potential (BMP) test, biogas production patterns, the lag phase and T90. The agricultural by-productions with high or medium carbohydrate and low fat (Cheese whey, Cabbage and Skimmilk) showed single step digestion process and low carbohydrate and high fat (Bean curd and, Perilla seed) showed two step digestion process.