脱水污泥高温两相与单相厌氧消化工艺比较研究

采用课题组自主研发的自动控温间歇搅拌高含固厌氧消化反应器,针对合肥市十五里河污水处理厂的脱水污泥(稀释至含固率10%)进行了超高温(70℃)酸化-高温(55℃)甲烷化和高温(55℃)酸化-高温(55℃)甲烷化两相与高温(55℃)单相厌氧消化系统性能的比较研究。结果表明,在污泥停留时间为两相产酸相4 d、产甲烷相16 d,单相20 d的条件下,超高温-高温和高温-高温两相的VS降解率分别为40.5%和40.2%,高温单相则只有34.9%。在总停留时间相等的条件下,两相消厌氧化系统的VS降解率、甲烷产率均比高温单相厌氧消化系统高,而出泥VFA含量小于高温单相厌氧消化系统。总体来说,两相厌氧消化系统运行更为稳定,效果更好,并且有较高的H2可供利用为清洁能源,但较高的H2S含量则须控制。

Comparison of Performance between Thermophilic Two-phase and Single-phase Anaerobic Digestion of Dewatered Sludge

Performance of thermophilic two-phase and single-phase anaerobic digestion treating dewatered sludge (diluted to 10% total solid content with distilled water) was experimentally studied and reported. The experimental results showed that volatile solid degradation rates of ultra-high, high-high temperature two-phase and thermophilic single-phase anaerobic digestion are 40.5%, 40.2% and 34.9%, respectively, while the sludge retention time of acidification phase is 4d, methanation phase is 16d, single-phase is 20d. The degrading efficiency of volatile solid and the methane yield of the two-phase anaerobic digestion are better than that of the single-phase anaerobic digestion in the same total sludge retention time. While the volatile fatty acids content is less. Overall, the two-phase anaerobic digestion system is more stable and more effective than single-phase anaerobic digestion, and the higher H2 is available for use as clean energy, but the control of high content of H2S is required.