Response of the Bacterial Consortium under Supersaturation Conditions in an Anaerobic Co-Digestion Environment between Typha domingensis and Bovine Manure

Abstract

Oversaturation in an anaerobic co-digestion environment occurs when two substrates with different bulk densities are used. In this case, the co-substrate with the higher bulk density has its ratio gradually increased without changing the water supply initially, while the ratio of the second co-substrate is decreased. In our case study, the ratio of Typha domingensis , which has a higher density than cattle manure, will gradually increase from 10% to 50%, the point at which the anaerobic environment becomes supersaturated. Since the optimum pH is between 6.1 and 7.1, the system’s temperature is dependent on the ambient temperature with a temporary variation between 28 and 36 degrees Celsius. This necessitates examining other parameters of the reaction medium that could explain this phenomenon. The relevant parameters are salinity, conductivity, and oxidation-reduction potential. The limit values obtained for these parameters are [2.4; 4.5 mS and 35.2 mV], respectively. This led us to question the performance of the overall process in terms of biogas composition, achieving a maximum CH 4 concentration of 55.59%.