Solubilization of Organics Due to Thermal Hydrolysis Pretreatment Leading to Stable Mesophilic Anaerobic Digestion

Abstract

A study was conducted to determine the effect of solubilzation due to thermal hydrolysis pretreatment on the microbial population responsible for anaerobic digestion at mesophilic temperature. Metagenomic and microbial population analysis was done on digester receiving thermal hydrolysis pretreatment as well as on conventional digester receiving no thermal hydrolysis pretreatment. The digester receiving thermal hydrolysis pretreatment was stable at lower detention times and showed shift in microbial population with predominance of methane producing population in comparison to conventional digesters receiving no thermal hydrolysis pretreatment. Among methanogens, Methanosarcina showed dominance in the THP digester. Conventional digesters had mixed culture of acid producing and methane producing population, with almost equal population of methane producing archaeal population -Methanobacterium and Methanosarcina. Kinetics showed high growth and substrate utilization rates in pilot digester receiving THP.