江苏省典型污水处理厂脱水污泥热值及其影响因素分析

以江苏省20家典型污水处理厂脱水污泥为对象,通过采样监测分析,探讨了目标污水处理厂脱水污泥干基热值特征,并采用偏相关、脱水污泥工业及元素分析等,研究影响污水处理厂污泥热值的因素。结果表明:江苏省脱水污泥的热值范围为5 328~15 069 kJ/kg,均值为9 883 kJ/kg,低于中国大中型城市平均水平,苏南地区脱水污泥热值显著高于苏中地区和苏北地区;偏相关分析结果显示,2011年絮凝剂种类与脱水污泥热值显著相关,2021年显著性因素为污水类型,混入工业废水和采用有机高分子絮凝剂均会对脱水污泥热值产生显著的正向影响;工业分析和元素分析结果显示,混入工业废水和采用有机高分子絮凝剂均会提高脱水污泥中有机物、挥发分及固定碳含量,与其对脱水污泥热值的影响规律一致;有机高分子絮凝剂的使用还更易使脱水污泥发生水解反应和脱碳酸反应。

Analysis of Heating Value and Influencing Factors of Dewatered Sludge from Typical Sewage Plant in Jiangsu Province

The dewatered sludge of 20 typical sewage treatment plants in Jiangsu Province was taken as the research object,the characteristics of dry base heating value of dewatered sludge from the target sewage plant were analyzed through sampling and monitoring tests,and the factors affecting the heating value of dewatered sludge in the sewage plant were discussed by partial correlation analysis, dewatered sludge industry analysis and element analysis. The results showed that the heating value of dewatered sludge in Jiangsu Province ranged from 5328 to 15069 kJ/kg,with an average of 9883 kJ/kg,which was lower than the average level of large and medium-sized cities in China, and the heating value of dewatered sludge in southern Jiangsu was significantly higher than that in central Jiangsu and northern Jiangsu. The partial correlation analysis results showed that the type of flocculants was significantly correlated with the heating value of dewatered sludge in 2011,the significance factor in 2021 was the type of dewatered sewage,and the mixing of industrial wastewater and the use of organic polymer flocculants had a significant positive impact on the heating value of dewatered sludge. The results of industrial analysis and elemental analysis showed that the mixing of industrial wastewater and the use of organic polymer flocculants increased the organic matter,volatiles and fixed carbon content in the dewatered sludge,which was consistent with the influence on the heating value of the dewatered sludge. The use of organic polymer flocculants would also make dewatered sludge more prone to hydrolysis and de-carbonization.