粉煤灰“工程型”及“产品型”资源化利用研究进展

粉煤灰是燃煤电厂排出的主要固体废物，同时也是含有有价组分的二次资源。粉煤灰综合开发不仅可以提高其资源化利用率，实现变废为宝，还能有效缓解因其长期堆积而造成的土地资源占用和环境污染问题。对粉煤灰的“工程型”及“产品型”资源化利用进行了梳理，在“工程型”利用方面，粉煤灰可大规模用于建筑行业，但产品附加值低，且其掺量有待进一步提高；可用于农业领域来改良土壤提升肥力，但需对其自身进行减毒处理；可在环境保护领域用于废气废水处理等，但负载了有害物质后的粉煤灰需要进行再处理。在“产品型”利用方面，可从粉煤灰中回收有价物质，如利用物理法分离微珠、磁珠及未燃碳以及利用化学法提取铝及关键金属等，但往往存在回收率及产品纯度低、易产生二次污染等问题；可用粉煤灰制备高附加值产品，增加经济效益，但目前产品种类少、制备成本高、市场接受度低。针对以上问题，从原料分类细化、产品攻关方向、行业标准制定、国家政策导向等角度为我国未来粉煤灰的资源化综合利用发展提出了合理建议。

Research Progress of "Engineering Type" and "Product Type" Resource Utilization of Coal Fly Ash

Coal fly ash (CFA) is the main solid waste discharged from coal fired power plants,and it is also a secondary resource containing valuable substance.The comprehensive development of CFA can not only improve its resource utilization rate and turn waste into treasure,but also effectively alleviate the problems of land resource occupation and environmental pollution caused by its long term accumulation.The current research status of resource utilization of CFA in the fields of "engineering type" and "product type" are sorted out.In terms of "engineering type" utilization,first,CFA can be used in the construction industry on a large scale,but the added value of the product is low,and its content needs to be further increased.Second,CFA can be used in agriculture to improve soil fertility,but it needs to be attenuated itself.Third,CFA can be used for waste gas and wastewater treatment in the field of environmental protection,but the CFA loaded with harmful substances needs to be reprocessed.In terms of "product type" utilization,first,valuable substances can be recovered from CFA,such as the separation of microbeads,magnetic beads and unburned carbon by physical methods,and the extraction of aluminum and key metals by chemical methods,but there are often problems such as low recovery rate and product purity,and prone to secondary pollution.Second,CFA can be used to prepare high value added products and increase economic benefits,but there are problems such as few product types,high preparation costs,and low market acceptance at present.In view of the above problems,reasonable suggestions are put forward for the future comprehensive utilization of CFA in China from the perspectives of classification refinement of raw materials,product research direction,industry standard formulation,and national policy orientation.