剩余污泥厌氧发酵耦合硫酸盐还原实现有机磷和铁结合态磷的同步释放

The one-way transport of P results in the lack of P resource. There is a great potential to recover P from waste activated sludge. The release of iron-phosphorus (Fe-P) from waste sludge is the bottleneck problem. The aim of this project was to improve the simultaneous release of organic P and Fe-P within an anaerobic fermentation combined with sulfate reduction (AF-SR) system. Synthetic system will be studied to reveal the symbiotic mechanism of acidogenic bacteria (AB) and sulfate reduction bacteria (SRB), and the competitive mechanism of SRB and iron reducing bacteria (IRB). The species and fraction of Fe, P, S will be tested to reveal the transform rule of different species from solid to liquid. The bio-chemical mechanism of P release would also be studied. Mathematic model of this AF-SR system will be setup and calibrated based on the real sludge system research, and then used for system simulation to get P release regulation strategies. Continuous flow reactor will be setup and operated to get the optimized simultaneous P release efficiency. Based on the AF-SR system, a new wastewater treatment and sludge treatment process was proposed, by which P, as well as N and C could be recovered from sludge at the same time, with Fe and S being recycled. If success, the results of this study could be used widely in the future.

自然界中磷的单向迁移导致磷资源的短缺，从剩余污泥中回收磷具有巨大应用潜力。课题针对铁结合态磷难以回收的瓶颈问题，以富磷剩余污泥为研究对象，以促进有机磷与铁结合态磷同步释放为主要目标，构建了污泥厌氧发酵耦合硫酸盐还原（AF-SR）体系：通过模拟体系实验研究，揭示硫酸盐还原菌与产酸菌、铁还原菌的共生竞争机制；通过研究污泥厌氧发酵、硫酸盐还原过程固、液两相中铁、磷、硫三种元素的存在形式与形态转化规律，解析铁结合态磷释放的生物化学原理；通过基于AF-SR体系的污泥厌氧释磷数学模型的构建、仿真和连续流反应器实验，优化污泥AF-SR体系释磷调控策略，实现有机磷与铁结合态磷的同步高效释放。基于提出的AF-SR体系设计的污水、污泥处理及资源化工艺，可实现Fe和S的循环利用，在高效回收磷的同时，还可回收污泥中的碳源（回用于污水生物脱氮）和氮源（可用作农肥），降低污水、污泥处理处置成本，具有广阔的应用前景。

自然界中磷的单向迁移导致磷资源的短缺，从剩余污泥中回收磷具有巨大应用潜力。课题针对铁结合态磷难以回收的瓶颈问题，以富磷剩余污泥为研究对象，以促进有机磷与铁结合态磷同步释放为主要目标，构建了污泥厌氧发酵耦合硫酸盐还原（AF-SR）体系，通过模拟体系实验研究，揭示了硫酸盐还原菌与产酸菌、铁还原菌的共生竞争机制；通过研究污泥厌氧发酵、硫酸盐还原过程固、液两相中铁、磷、硫三种元素的存在形式与形态转化规律，解析了铁结合态磷释放的生物化学原理；通过基于AF-SR体系的污泥厌氧释磷模型的构建和连续流反应器实验，优化了污泥AF-SR体系释磷调控策略，实现了有机磷与铁结合态磷的同步高效释放，释放到发酵液中的磷浓度可高达284.2 mg/L。基于提出的AF-SR体系设计的污水、污泥处理及资源化工艺，在某城市污水厂建立了100立方米/天的全流程生产性实验装置，实现了在高效回收磷的同时，同步回收污泥中的碳源（回用于污水生物脱氮），降低了污水、污泥处理处置成本，具有广阔的应用前景。