污泥生物炭-高铁酸盐协同调理改善污泥脱水性能机理研究

Sewage sludge biochar is solid material obtained from pyrolysis of the sewage sludge, which possesses some similar properties to sewage sludge coagulant, ferrate can efficiently rupture the sewage sludge extracelluar polymeric substances, hence, the sewage sludge will be dewatered easily and efficiently when it is synergetic conditioned with the sewage sludge biochar and ferrate. The sewage sludge biochar is first employed in sewage sludge conditioning in this research, through analyzing the sewage sludge biochar properties and the relevant properties of conditioned sewage sludge, contribution of sewage sludge biochar properties on the improvement of the conditioned sewage sludge dewaterability is determined, and their correlation mechanism is established.In addition, the multidimensional conditioning mechanism of the sewage sludge biochar is revealed through analyzing relevant properties of the conditioned sewage sludge, such as pH，Zeta potential, flocculation microstructure, compressibility, and sludge cake microstructure.The research of sewage sludge synergetic conditioning with the sewage sludge and ferrate is conducted based on the sewage sludge ferrate conditioning. Their synergetic conditioning mechanism is uncovered, through comparing and analyzing sewage sludge biochar alone, ferrate alone, and both of their conditioning experiment results. Above all, the substantial fundamental data and relevant theory would be established to develop a sewage sludge dewatering way based on sewage sludge and ferrate synergetic conditioning. Hence, this research will be of great importance to dewater sewage sludge in an environmental friendly, efficient, and low cost manner, and to sewage sludge energy and resource utilizations.

污泥生物炭是污泥热解固态产物，具备污泥絮凝剂基本性质；高铁酸盐可有效破解污泥胞外聚合物；污泥生物炭与高铁酸盐协同调理对于改善污泥脱水性能具有良好预期。本研究首次将污泥生物炭用于污泥调理，通过分析污泥生物炭相关性质以及调理后污泥脱水性能变化，明确污泥生物炭特性对污泥脱水性能改善的贡献比例，建立其关联机制。通过分析调理后污泥pH、Zeta电位、絮体微观结构、压缩系数、泥饼微观结构等性质参数变化，揭示污泥生物炭多途径调理机理。结合高铁酸盐氧化调理方法，开展污泥生物炭与高铁酸盐协同调理研究，通过逐项比对分析污泥生物炭、高铁酸盐单独调理以及协同调理后污泥性质及脱水性能变化，揭示其协同调理机制。本研究可为建立污泥生物炭与高铁酸盐协同调理改善污泥脱水方法提供基础数据与理论依据，对于实现污泥绿色、高效、低成本脱水，以及最终能源化、资源化综合利用具有重要意义。

污泥生物炭是污泥热解固态产物，具备絮凝剂基本性质；高铁酸盐可有效破解污泥胞外聚合物；二者协同调理对于改善污泥脱水性能具有良好预期。本研究通过分析污泥生物炭相关性质以及调理后污泥脱水性能变化，建立其关联机制。通过分析pH、Zeta电位等性质参数变化，揭示污泥生物炭多途径调理机理。结合高铁酸盐氧化调理方法，开展二者协同调理研究，揭示其协同调理机制。. 污泥生物炭单独调理时，其所含金属阳离子与污泥体系中阴离子结合，降低污泥体系稳定性，污泥生物炭中有机官能团与污泥絮体进行结合增大团块体积，使得污泥絮体迅速沉降，污泥生物炭的介孔结构在压滤过程中起到骨架构建体的作用，在脱水过程中提供水流通道。协同调理时，污泥生物炭中的金属阳离子与污泥体系中阴离子结合，高铁酸盐还原产物Fe(OH)3产生絮凝沉淀作用，共同降低污泥体系稳定性；污泥生物炭中有机官能团与污泥絮体进行结合增大团块体积，使得污泥絮体迅速沉降。高铁酸钾通过强氧化作用，破解污泥胞外聚合物，一方面使污泥中结构水转化为自由水，利于水分析出；一方面胞外聚合物碎片堵塞流水通道，抑制水分析出，污泥生物炭的介孔结构起到骨架构建体的作用，利于水分析出。进一步的，通过核磁共振的方法分析了泥饼中水分分布，实现了水分空间分布可视化，根据水分受束缚程度，首次将泥饼中的残余水分划分为强结合水，弱结合水，毛细管水。. 本研究可为建立污泥生物炭与高铁酸盐协同调理改善污泥脱水方法提供基础数据与理论依据，对于实现污泥绿色、高效、低成本脱水，以及最终能源化、资源化综合利用具有重要意义。