垃圾焚烧飞灰的石材化固化处理

为促进垃圾焚烧飞灰的无害化处理及资源化利用,提出了一种石材化固化处理方法,并对其产物的使用性能、毒物浸出特性及该方法的经济效益进行探索。结果表明:该处理方法利用C80PHC生产中高温、高压、高湿环境及磨细石英砂的存在使水泥水化产物转变为托贝莫来石,一方面提高混凝土的致密性及强度,减少毒物浸出通道;另一方面将毒物包容或固结在其石材化的晶格中,几乎杜绝了毒物浸出。同时其产物的脱模强度及高压蒸养强度均满足C80PHC的使用要求,从而确保了其资源化利用的可行性。石材化固化处理的处理成本仅约为108.1元/t,使用时也无需额外占用土地、增加设备和材料成本,因此有望在低成本条件下达到无害化处理的工艺水平,是一项经济、环保、可靠的创新技术。

Stone solidifying treatment of MSWI fly ash

A stone solidifying treatment was investigated in this study in order to improve the harmless treatment and resource utilization of municipal solid waste incineration (MSWI) fly ash.The economic benefits of the treatment, the service performance, and the leaching toxicity were analyzed.The results showed that the cement hydrates were transformed into tobermorite in the stone solidifying process when fine quartz sand was added and a high-temperature, high-pressure, high-humidity environment was used to manufacture C80PHC concrete.The density and strength of the concrete increased, which reduced the toxic leaching channel volume.Furthermore, the toxic components of MSWI fly ash were immobilized by the containment and solidification of tobermorite, which stopped toxic compounds leaching out.The results also showed that the method could create a recycling use for the tobermorite with demolding and an autoclaving compressive strength that satisfy the requirements for C80PHC concrete.The economic cost of the treatment was about 108.1 yuan/t, without adding material and equipment costs, and the area of land used.Therefore, the treatment is cost-effective, environmentally-friendly, and safe because it can achieve the required level of harmless disposal at low costs.