污泥高温厌氧消化产甲烷及病原指示微生物灭活的研究

试验研究了剩余污泥在适宜碳氮质量比条件下,高温厌氧消化对产甲烷及病原指示微生物灭活的影响,分析比较了厌氧消化前、后污泥中病原指示微生物数量的变化。结果表明,高温厌氧消化能够有效地将污泥中的有机物分解,产生沼气,并且能够有效地杀灭上清液和污泥中的大肠杆菌、粪大肠杆菌和沙门氏菌。经过28d,55℃的高温厌氧消化后,消化液中总大肠杆菌下降约2.9个数量级、粪大肠杆菌下降约2.6个数量级,消化污泥中总大肠杆菌量下降3.4³.6个数量级、粪大肠杆菌量下降3.83.6个数量级、粪大肠杆菌量下降3.8⁴.3个数量级,而且在消化液和消化污泥中均未检测到沙门氏菌的存在。在适宜的碳氮质量比的条件下,高温厌氧消化能够有效地杀灭消化液和消化污泥中的病原指示微生物。

Study on methane producing bacteria and pathogenic microorganism inactivation by thermophilic anaerobic digestion

The effect of thermophilic anaerobic digestion on inactivation of methane producing bacteria and pathogenic microorganism in excess sludge with proper C/N ratio was studied, the pathogenic microorganism num- bers in the sludge before and after the anaerobic digestion were analyzed and compared. The results showed that, thermophilic anaerobic digestion could not only availably resolve the organic matters in the sludge and produce methane at the same time, but also kill the colon bacillus, fecal coliform and salmonella in the supernatant and the sludge effectively. Through a 28-d thermophilic anaerobic digestion at 55 ℃, the number of total coliforms and fecal coliform in the digested liquid decreased about 2.9 and 2.6 orders of magnitude respectively, and the number of those bacillus in the digested sludge decreased 3.4 - 3.6 and 3.8 - 4.3 orders of magnitude respec- tively; furthermore, no salmonella was found in digested liquid or digested sludge. It could draw a conclusion that, thermophilic anaerobic digestion could effectively kill pathogenic microorganism in digested liquid and di- gested sludge with proper C/N mass ratio.