tailieunhanh - báo cáo hóa học: " Escherichia coli inactivation kinetics in anaerobic digestion of dairy manure under moderate, mesophilic and thermophilic temperatures"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Escherichia coli inactivation kinetics in anaerobic digestion of dairy manure under moderate, mesophilic and thermophilic temperatures | Pandey and Soupir AMB Express 2011 1 18 http content 1 1 18 o AMB Express a SpringerOpen Journal ORIGINAL Open Access Escherichia coli inactivation kinetics in anaerobic digestion of dairy manure under moderate mesophilic and thermophilic temperatures Pramod K Pandey and Michelle L Soupir Abstract Batch anaerobic digestion experiments using dairy manure as feedstocks were performed at moderate 25 C mesophilic 37 C and thermophilic C temperatures to understand E. coli an indicator organism for pathogens inactivation in dairy manure. Incubation periods at 25 37 and C were 61 41 and 28 days respectively. Results were used to develop models for predicting E. coli inactivation and survival in anaerobic digestion. For modeling we used the decay of E. coli at each temperature to calculate the first-order inactivation rate coefficients and these rates were used to formulate the time - temperature - E. coli survival relationships. We found the inactivation rate coefficient at C was 17 and 15 times larger than the inactivation rate coefficients at 25 and 37 C respectively. Decimal reduction times D10 time to achieve one log removal at 25 37 and C were 9 -10 7 - 8 days and 1 day respectively. The Arrhenius correlation between inactivation rate coefficients and temperatures over the range 25 C was developed to understand the impacts of temperature on E. coli inactivation rate. Using this correlation the time - temperature - E. coli survival relationships were derived. Besides E. coli inactivation impacts of temperature on biogas production methane content pH change ORP and solid reduction were also studied. At higher temperatures biogas production and methane content was greater than that at low temperatures. While at thermophilic temperature pH was increased at mesophilic and moderate temperatures pH were reduced over the incubation period. These results can be used to understand pathogen inactivation during anaerobic digestion of