Zhao Xin-Yue, Yang Jin-Yan, Ning Ning, Yang Zhi-Shan
College of Architecture and Environment, Sichuan University, Chengdu, 610065, People's Republic of China.
Chengdu Winna Environmental Technology Co., Ltd, Chengdu, 610065, People's Republic of China.
Environ Sci Pollut Res Int. 2022 Jun;29(27):40384-40402. doi: 10.1007/s11356-022-19649-2. Epub 2022 Mar 26.
Sufficient attention should be attached to the large amount of fly ash containing high levels of toxic heavy metals generated after municipal solid waste incineration. Because heavy metals could be leached out of the fly ash under specific conditions, it is necessary to stabilize the heavy metals in fly ash before landfill disposal. Processing technologies of incineration fly ash include solidification/stabilization technology, thermal treatments, and separation processes. This study reviewed the current treatment technologies of municipal solid waste incineration (MSWI) fly ash, with the main focus on the treatment of heavy metals in fly ash with chemical stabilization. Chemical stabilization processes involve chemical precipitation of heavy metal and chelation of heavy metals. In multiple studies, chemical stabilization technology has shown practical feasibility in terms of technology, economy, and effect. In addition, the combination of two or more stabilization agents broadens the general applicability of the agents to heavy metals and reduces the cost. The application of joint processing technology realizes the remove of soluble salt from fly ash. To minimize pollutants while increase their usable value, effective use of waste and co-disposal of several kinds of wastes have gradually become the research hotspots. New developments in chemical stabilization are progressively moving towards the sustainable direction of harmlessness and resource utilization of MSWI fly ash.
应充分关注城市固体废物焚烧后产生的大量含有高浓度有毒重金属的飞灰。由于在特定条件下重金属可能会从飞灰中浸出，因此在填埋处置前对飞灰中的重金属进行稳定化处理很有必要。焚烧飞灰的处理技术包括固化/稳定化技术、热处理和分离工艺。本研究综述了当前城市固体废物焚烧（MSWI）飞灰的处理技术，主要关注采用化学稳定化处理飞灰中的重金属。化学稳定化过程包括重金属的化学沉淀和螯合。在多项研究中，化学稳定化技术在技术、经济和效果方面均显示出实际可行性。此外，两种或更多种稳定剂的组合拓宽了这些药剂对重金属的普遍适用性并降低了成本。联合处理技术的应用实现了飞灰中可溶性盐的去除。为了在增加其可用价值的同时将污染物降至最低，有效利用废物以及几种废物的协同处置已逐渐成为研究热点。化学稳定化的新发展正逐步朝着MSWI飞灰无害化和资源利用的可持续方向发展。
