Abstract:

The production of municipal sewage sludge in China is about to reach 90 million tons. Harmless, reduction and resource disposal for them is very urgent. The mass fraction of phosphorus in dried sewage sludge is 2%—6%. The potential is highly great for recycling phosphorus resource from sewage sludge. This not only reduces the consumption of phosphorus ore, but also alleviates global phosphorus crisis. The discussion about the recovery and utilization of phosphorus resource from sewage sludge focuses on five aspects, including sewage sludge disposal technologies, phosphorus content and speciation in dewatering sewage sludge, phosphorus speciation transformation during these thermal treatments (pyrolysis, incineration, gasification, hydrothermal carbonization), phosphorus recovery methods from sewage sludge ash/char and plant absorbability of phosphate minerals. It is also comparatively analyzed in detail that the effect of different factors including temperature, additive components and blending fuel types on phosphorus speciation in thermal treatment products. Finally, it is summarized and contrastively analyzed that the recovery processes of phosphorus from thermal treatment products and different factors influencing on the phosphorus recovery. Meanwhile, the plant availability for the recovered phosphate minerals were also discussed. This review could provide some suggestion for the resource utilization of phosphorus from sludge in China in the future.

Key words: municipal sewage sludge, phosphorus, thermal chemical treatment, recovery

摘要：

我国市政污泥产量即将突破9000万吨，无害化、减量化和资源化处置非常迫切。干污泥中磷元素含量占2%～6%，回收磷资源的潜力巨大，其可以减少有限磷矿的消耗，缓解全球磷危机。本文从污泥处置技术、脱水污泥中磷元素含量与形态、热化学（热解、焚烧、气化和水热炭化）处理中磷元素形态转变、污泥灰/炭中磷元素回收方法和含磷矿物的植物可吸收性五个方面对污泥中磷资源回收与利用展开论述，详细对比分析了温度、添加剂成分、掺混燃料种类等因素对热处理产物中磷元素形态的影响。最后，归纳分析了热处理产物中磷元素的回收工艺和不同因素的影响以及含磷矿物的植物可吸收性，以期为我国未来污泥资源化利用提供参考。

关键词: 市政污泥, 磷元素, 热化学, 回收