应用好氧生物菌剂深度处理消化污泥

Advanced treatment of digested sludge using an aerobic bacterium

为评估应用好氧生物菌剂—地衣芽孢杆菌深度处理消化污泥的可行性,比较了不同接种比(分别为2.7×10^(-3),2.7×10^(-2)和2.7×10^(-1),以总固体之比计)条件下,菌解处理过程中消化污泥液相的溶解性有机碳DOC,溶解性总氮DN,氨氮,荧光性有机物浓度和消化污泥絮体中的蛋白质,氨氮浓度,以及以模化CST值表征的脱水性能的变化,同时分析了机械破碎法和菌解法对消化污泥再次厌氧消化产气性能的影响.结果表明,需要达到较高的接种比,投加地衣芽孢杆菌才能显著促进消化污泥胞内物质溶出,大幅提高消化污泥的生物可降解性.接种比为2.7×10-1时,菌解过程中消化污泥的液相DOC,DN,氨氮和消化污泥絮体中的氨氮含量达到最大值,分别是对照组的6.23,2.83,5.93和4.94倍;并且,消化污泥絮体的蛋白质平均降解速率最高;同时,消化污泥的产甲烷潜力优于其它接种比,是机械破碎处理后消化污泥产甲烷潜力的5.96倍.但是,在菌解处理结束后,消化污泥的模化CST值是对照组的2.69倍,说明经菌解后消化污泥的脱水性能有所劣化.

In order to evaluate the feasibility of applying Bacillus licheniformis as an aerobic bacterium on advanced treatment of digested sludge, dissolved organic carbon, dissolved total nitrogen, ammonia nitrogen concentration in the liquid phase of digested sludge and the protein, ammonia nitrogen concentration and modeled CST value in the digested sludge flocs, were measured at different inoculation ratios （respectively 2.7×10-3, 2.7×10-2, 2.7×10-1, total solid ratio）, while the effects of mechanical disintegration method and bacterial treatment method on secondary digestion and gas production of digested sludge were also compared. The results showed that the addition of Bacillus licheniformis required a higher inoculation ratio to significantly promote the dissolution of digested sludge into the phase and to improve the biodegradability of digested sludge. When the inoculation ratio of Bacillus licheniformis was 2.7×10-1, DOC, DN, ammonia nitrogen concentration in the liquid phase and ammonia nitrogen concentration in the digested sludge flocs reached the maximum accumulative values during the bacterial treatment, which was respectively 6.23, 2.83, 5.93 and 4.94 times of that of the control group. The maximum degradation rate of protein was also observed in the digested sludge flocs. At this inoculation ratio 2.7×10-1, the biochemical methane potential of the digested sludge was superior to that of other inoculation ratio and was 5.96 times of that of the digested sludge treated by mechanical disintegration. Therefore, this method of bacterial treatment was beneficial to further deepen the utilization of residual refractory organic matter in digested sludge and to improve its biodegradability and final stability after digestion. However, after the bacterial treatment, the modeled CST value of digested sludge was 2.69 times of that of the control group, which deteriorated the dewaterability of the digested sludge.