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采用水热反应处理污水污泥以获得合适的产物，研究了170~270℃温度范围内水热反应温度对3种产物(水热炭、水热液、气体)的产量和特性的影响，并确定最适合的反应温度。研究表明水热反应有效改善了污泥的脱水性和流动性，通过离心分离含水率可下降到60%以下。污泥中的碳元素主要保留在水热炭中，水热炭热值满足作为燃料的要求。随反应温度升高，污泥中固体被分解的量增加，干物质量减少，产率最高仅原泥的12.94%。温度大于230℃的液体具有较好的可生化性。重金属元素富集到了水热炭中，且稳定性好。反应温度越高，气体中可燃成分浓度越高。用于水热反应的反应釜存在严重的结焦倾向，提高反应温度有利于减轻结焦。总体上，260℃水热温度下3种产物的特性适合后处理、结焦倾向最轻，是适合的反应温度选择。“,”Hydrothermal process is applied to sewage sludge for its safe disposal and energy recovery. The influence of reaction temperature on the properties of products (char, liquid and gas) was investigated within the range of 170~270℃ with purpose to determine the proper temperature. Experimental results show that hydrothermal treatment effectively improve the dehydration and mobility of sewage sludge; and moisture content of the solid product (char) decreases below 60% after centrifugal separation. Carbon is tended to remain in the char; and the calorific value of the char met the requirements as low grade fuel, which proves that hydrothermal treatment is an effective way to turn sludge into solid fuel. As temperature rises, more solid matter decomposes, making the dry matter contents are negatively correlated with temperature; and its highest yield is only 12.94%. When temperature is higher than 230℃, the liquid from hydrothermal process is biodegradable. Heavy metals in the sludge are mainly accumulated in the char and become stable. As temperature increases, the combustible components in the gas product increase accordingly. The hydrothermal reactor has a serious problem of coking on the wall, while high temperature is beneficial to alleviate coking. Generally, the temperature of 260℃ corresponds to the acceptable products and light coking effect and can be recommended as operation temperature of hydrothermal process.