不同温度水热处理对高含固污泥有机物转化及组分的影响

以城市污水处理厂的高含固污泥为研究对象，探讨其在不同水热预处理温度条件下，污泥中有机物水解效果及组分构成的变化情况。结果表明：在不同的水热预处理温度下(140、170、200、230和260 ℃)，均可有效地水解污泥中有机物；在温度170 ℃的条件下预处理30 min，水解后的污泥中，SCOD、溶解性蛋白质和溶解性碳水化合物浓度均达到最高，分别为40.71、20.56和9.10 g·L⁻¹。对水解上清液进行傅里叶红外分析发现，在170 ℃时，污泥中的蛋白质和碳水化合物被充分水解，上清液中含有大量O—H键。对水解上清液进行三维荧光检测结合积分区域法(FRI)分析发现，在170 ℃时，可生物利用的微生物代谢产物所占比例最大(38.68%)，微生物难降解的腐殖酸类物质所占比例最小(37.47%)。高含固污泥在170 ℃、30 min的预处理条件下，污泥中大分子有机物被分解为小分子有机物；同时，可供微生物利用物质所占比例最大，更有利于污泥后续的资源化利用。

Effect of thermal hydrolysis treatment temperature on transformation and composition of organic matter in high solid content sludge

In this study, high solid content sludge in municipal wastewater treatment plant (WWTP) was taken as the research object, the changes in hydrolysis effect and composition of organic matter in sludge under different hydrothermal pretreatment temperatures were discussed. The results showed that organic matter in the sludge could be effectively hydrolyzed at different hydrothermal pretreatment temperatures of 140, 170, 200, 230 and 260 ℃. After 30 min treatment at 170 ℃, the concentrations of SCOD, soluble proteins and soluble carbohydrates reached their own highest value of 40.71, 20.56 and 9.10 g·L−1, respectively. Fourier infrared analysis of the hydrolyzed supernatant revealed that at 170 ℃, the protein and carbohydrates in the sludge were sufficiently hydrolyzed, and a large number of O—H bonds appeared in the supernatant. Three-dimensional fluorescence analysis and fluorescence regional integration (FRI) of hydrolyzed supernatant revealed that the bioavailable microbial metabolites accounted the largest proportion of 38.68% at 170 ℃, while the hardly micro-biological degradable humic acids accounted for the smallest proportion of 37.47%. When the high solids content sludge was pretreated for 30 min at 170 ℃, the macromolecular organics in the sludge were decomposed into small molecular organics. At the same time, the proportion of microbially available substances reached the largest value, which was more conducive to the subsequent resource utilization of sludge.