市政污泥热处理过程中磷迁移转化的研究进展

Review on phosphorus migration and transformation during municipal sewage sludge heat treatment

磷(P)是生物生长必不可少的营养物质,在自然界中主要以磷酸盐矿物质形式存在。污泥作为一种富磷的固体废物,可作为二次磷资源开发利用。本文对不同热处理方式(焚烧、热解、水热炭化)中污泥的磷迁移转化规律和影响进行了综述,热处理方式不仅可以缓解磷资源危机,促进磷资源的循环利用,而且可以减少污泥带来的环境问题,并生成有价值的副产品。在此基础上,归纳了不同添加剂(配煤、生物质和碱土化合物)对污泥中磷迁移转化的行为影响规律及机制,发现添加剂的加入可以促进热处理过程中磷的富集,并改变磷的赋存形态,从而提高灰中磷的生物可利用性。

Phosphorus(P)is an essential nutrient for biological growth,which exists mainly in the form of phosphate minerals.As a kind of phosphorus-rich solid waste,sludge can be used as a secondary phosphorus resource.In this paper,the rules and effects of phosphorus transformation in sludge under different heat treatment methods(incineration,pyrolysis,hydrothermal carbonization)are summarized.Heat treatment can not only alleviate the crisis of phosphorus resources and promote the recycling of phosphorus resources,but also reduce the environmental problems caused by sludge and generate valuable by-products.On this basis,the influence rules and mechanisms of different additives(coal blending,biomass,and alkaline earth compounds)on phosphorus migration and transformation in sludge are summarized.It is found that the additives could promote the enrichment of phosphorus during heat treatment and change the occurrence form of phosphorus,and increase the biological availability of phosphorus in the ash.This may provide a valuable reference for the research of phosphorus resource recovery and utilization in the process of sludge heat treatment.