力-化学耦合作用下市政污泥水分释放的微观机理研究

Aiming at the urgent problem of dewatering for municipal sludge and around the water release microscopic mechanisms of municipal sludge under mechanical - chemical coupling effects, a series of experiments on water release properties were performed. By adopting methods in geotechnical engineering, seepage mechanics, applied chemistry, environmental engineering and solid waste disposal engineering, efforts were made to probe into the changing laws of water seepage, water distribution and porosity during the water release of municipal sludge under mechanical - chemical coupling effects, and the fractal dimension expression of sludge particles involved in organic matter, water content, CST, pH, zeta potential and other major physical and chemical indicators. Based on these, nonlinear water release time effect model in line with sludge properties was established. Besides, the numerical solutions and calculation procedures for multivariable nonlinear water release model were studied, and the evolution laws for water release of municipal sludge under mechanical - chemical coupling effects were analyzed. These have opened up theoretical and technological ideas for optimized design of further sludge dewatering system in China.

针对国家对市政污泥处理处置中迫切需要解决的脱水问题，围绕力-化学耦合作用下市政污泥水分释放的微观机理，通过一系列水分释放特性试验，采用岩土工程、渗流力学、应用化学、环境工程以及固废处置工程等多学科交叉方法，探讨力-化学耦合作用下市政污泥水分释放过程的水分渗出、水分分布和孔隙率的变化规律，及包含有机质、含水率、CST（毛细吸水时间）、pH和电位等主要理化指标的污泥颗粒分形维数表达式，并以此建立符合污泥系统特性的水分释放非线性时效模型；研究含多变量的非线性水分释放模型的数值解法和计算程序，分析力－化学耦合作用下市政污泥水分释放的发展演变规律。为我国城市污泥深度脱水系统的优化设计与资源化利用提供理论基础与科学技术支持。

本项目基于自主研发的泥浆低压与高压过滤压缩脱水测试装置，开展了化学氧化处理与力学加载条件下市政污泥脱水试验，分析了市政污泥的理化性质影响规律，研发了作为骨架构建助滤剂的淤泥改性活化材料的制备工艺，研究了力学加载条件、化学氧化处理和骨架构建促进污泥固液分离能力改善的作用机理，提出了骨架构建的复合调理剂优选配比方案，建立了预测污泥脱水的水分释放非线性模型。研究成果本项目共发表SCI论文5篇，EI论文1篇，中文核心论文1篇；主编省级工法1项；参编标准规范4项；申请发明专利7项；获得2017中国专利优秀奖，获得2018年中国技术市场金桥奖项目突出贡献奖；培养博士研究生2名，联合培养硕士研究生1名。