Beneficial Anaerobic Bacteria Flora Proliferation Regularity in the Process of Rehmannia Waste Residue Anaerobic Fermentation

Abstract

Based on a self-regulating mesophilic anaerobic reactor, we did a mesophilic anaerobic ferment test on rehmannia residue. This experiment systematically investigated the amount change of the methane production as the anaerobic reaction time changes. We concluded the proliferation regularity of beneficial anaerobic bacteria flora through accumulative methane production during the zero-order reaction period of anaerobic ferment. The results show that based on the mesophilic reaction temperature which is 37±1°C, when the feeding cycle is 7 days, after the 56 days continuous operation, the methane production potential is 92.8mL/(g•VS), the inflection point of the 0∼1 order reaction would gradually advance, we find mostly negligible change of cumulative methane production in each cycle; when the feeding cycle was changed to 10hours, the anaerobic bacteria flora was in a state without substrate competition, in this period, we find a linear relationship between the logarithm of the amount of cumulative methane in each cycle and the reaction time: y = 0.0506x + 7.295, the specific growth rate of beneficial bacteria flora is 0.121d-1,the doubling time is 5.7 days. The research can give references for engineering design of the Chinese medicine residue anaerobic treatment and semi-continuous anaerobic treatment.