School of Environmental Science and Engineering, Peking University

作为植物生长的必需营养元素之一,磷在现代农业的发展中发挥着不可忽视的作用,并且需求量巨大。 由于全球的磷储量有限且磷资源不可再生,污泥焚烧灰因其中磷含量较高且年产量巨大被认为是一种潜在的二次磷资源。 本文综述了基于湿化学技术从污泥焚烧灰中回收磷的研究现状,该技术主要包括磷提取过程及后续的磷产品生产过程。 磷提取过程主要包括基于酸性试剂的酸提取技术,基于碱性试剂的碱提取技术以及多种方式组合的连续提取技术。 磷产品生产过程主要通过化学沉淀和晶体沉淀的方法从富磷溶液中生产磷产品,一般为钙磷、鸟粪石以及蓝铁矿,这三种磷产品都可以作为磷肥促进植物生长。 基于湿化学技术从污泥焚烧灰中回收磷产品的难点是其中富集有大量的重金属等杂质元素,因此需要通过各种纯化预处理手段降低溶液中的杂质含量,以提高后续回收的磷产品纯度。 本文总结了基于湿化学技术的各种纯化预处理手段,主要包括离子交换除杂技术,磷吸附-解吸附技术,以及通过控制 pH 的沉淀除杂技术等。 本文探讨了从污泥焚烧灰中回收磷产品的可行性及必要性,总结了基于湿化学技术从其中回收磷产品的方法及技术路线,分析了湿化学技术回收污泥焚烧灰中磷产品的基本原理,为开发新的从其中回收磷的技术提供了参考。

As one of the essential nutrients for plant growth, phosphorus plays an indispensable role inthe development of modern agriculture and is in great demand. Since global phosphorus reserves arelimited and phosphorus resources are not renewable, incinerated sewage sludge ash (ISSA) is consid⁃ered to be a potential secondary phosphorus resource due to its high phosphorus content and huge annu⁃al production. The paper summarizes the current status of research on the recovery of phosphorus fromISSA based on wet-chemical technology, which mainly includes the phosphorus extraction process andthe subsequent production process of phosphorus products. The phosphorus extraction process mainlyinvolves acid extraction using acidic reagents, alkaline extraction based on alkaline reagents, and con⁃tinuous extraction with a combination of various methods. The phosphorus production process primarilyyields phosphorus products from phosphorus-rich solutions by means of chemical precipitation and crys⁃tal precipitation, generally yielding calcium phosphorus (Ca-P), struvite (MgNH4PO4·6H2O) andvivianite (Fe3(PO4) 2·8H2 O), all of which can be used as phosphorus fertilizers to promote plantgrowth. The difficulty of recovering phosphorus products from ISSA based on wet-chemical technologyis that sludge incineration ash is enriched with a large number of heavy metals and other impurity ele⁃ments, and it is necessary to reduce the content of impurities in the solution through various purificationpretreatment means, so as to improve the purity of the subsequently recovered phosphorus products. Inthis paper, various purification pretreatment means based on wet-chemical technology are reviewed,mainly including ion exchange impurity removal technology (CER), phosphorus adsorption-desorptiontechnology, and precipitation impurity removal technology through pH control. In conclusion, thispaper discusses the feasibility and necessity of recovering phosphorus products from ISSA, summarizingthe methods and technical routes of recovering phosphorus products from ISSA based on wet- chemicaltechnology, revealing the basic principles of recovering phosphorus products from ISSA using wet chemical technology, and providing technical references for developing new technologies for recoveringphosphorus from ISSA.

国家自然科学基金资助项目(52100021,52200140)

胡少刚, 张婧, 杨武霖. 基于湿化学技术从污泥焚烧灰中回收磷的研究进展[J]. 能源环境保护, 2023, 37(5): 86-98.

HU Shaogang, ZHANG Jing, YANG Wulin. Research progress on phosphorus recovery from incinerated sewagesludge ash based on wet-chemical techniques[J]. Energy Environmental Protection, 2023, 37(5): 86-98.