Influence of Hydraulic Retention Time and Reactor Configuration During Fermentation of Diluted Chicken Manure.

In this study, single-stage and two-phase semi-continuous thermophilic anaerobic reactors fed with diluted (3 % total solids (TS) and 1.8 % volatile solids (VS)) chicken manure at three different hydraulic retention times (HRTs) were compared interms of biogas production rate, methane content of the produced biogas, and VS and TS removal. Along the study, HRTs of 16, 12, and 8 days were implemented to the single-stage and the two-phase systems. It was observed that the single-stage anaerobic system was superior to the two-phase anaerobic system according to their biogas production rates (517 vs. 356, 551 vs. 359, 459 vs. 386 (mL/g VSfeed)) at all HRTs. On the other hand, methane content of the biogas produced was higher in the two-phase system compared to the single-stage system.

Biogas production from chicken manure at different organic loading rates in a mesophilic-thermopilic two stage anaerobic system.

This study investigates the biogas production from chicken manure at different organic loading rates (OLRs), in a mesophilic-thermophilic two stage anaerobic system. The system was operated on semi continuous mode under different OLRs [1.9 g volatile solids (VS)/L·d - 4.7 g VS/L·d] and total solid (TS) contents (3.0-8.25%). It was observed that the anaerobic bacteria acclimatized to high total ammonia nitrogen concentration (>3000 mg/L) originated as a result of the degradation of chicken manure. High volatile fatty acid concentrations were tolerated by the system due to high pH in the reactors. The maximum average biogas production rate was found as 554 mL/g VSfeed while feeding 2.2 g VS/L-d (2.3% VS - 3.8% TS) to the system. Average methane content of produced biogas was 74% during the study.