Based on a comprehensive characterization of the pollution nature of incineration fly ash from urban domestic waste in our country, and targeting its pollution characteristics, comparative selection and experimental research were conducted on fly ash stabilization agents and processes. A fly ash stabilization combined treatment technology with independent intellectual property rights was developed. This technology combination applies both chemical and physical mechanisms, stabilizing heavy metals in the fly ash into extremely low water-soluble compounds with geochemical stability. After treatment, the concentration of pollutants in the fly ash is below the limit specified by the 'Domestic Waste Landfill Pollution Control Standard GB16889-2008' for disposal in sanitary landfills, meeting the long-term environmental safety requirements for disposal in sanitary landfills. Based on the patented process, key equipment selection and improvement, design optimization, and operational parameter tuning were carried out. This achievement has enabled the long-term operation of a chemical stabilization treatment project for incineration fly ash under the composition background of domestic municipal solid waste, becoming the first engineering application instance in China after the promulgation of GB16889-2008 standard, reaching the leading level of harmless treatment for fly ash. Engineering operation practice has confirmed that the stabilized fly ash using this achievement meets the following main performance indicators: 1) Key heavy metal leaching concentration: As ≤ 0.02mg/L, Ba ≤ 0.8mg/L, Be ≤ 0.0002mg/L, Cd ≤ 0.1mg/L, Cr ≤ 0.1mg/L, Cu ≤ 0.2mg/L, Hg ≤ 0.01mg/L, Ni ≤ 0.2mg/L, Pb ≤ 0.1mg/L, Se ≤ 0.03mg/L, Zn ≤ 0.3mg/L; 2) Water content < 30%; 3) Dioxin content is below 3 µgTEQ/kg; 4) The volume increase rate is <10%. The harmless treatment indicators of fly ash monitored by a third party are leading in domestic and international similar engineering projects, as well as in the potentially developing alternative technologies internationally (Shanghai Science and Technology Information Institute Level Retrieval Report 20101890SH). Compared with similar foreign technologies, the stabilized fly ash product of this achievement has advantages such as long-term environmental safety, convenient landfilling operations, and a small volume increase ratio. The heavy metal stabilization indicators are even better, while there have been no similar engineering scale application research reports domestically. Engineering practice shows that the comprehensive cost of fly ash stabilization treatment and subsequent sanitary landfilling disposal is 540 yuan/ton. Compared with the current mainstream comprehensive cost of fly ash solidification or stabilization treatment followed by safe landfilling at hazardous waste disposal sites, it saves more than 400 yuan/ton; The landfill volume has also decreased by 20%. This achievement replaces the costly and very limited capacity of secure landfilling with sanitary landfilling, which has significant economic and environmental benefits. The result has great value for promotion and application, and it plays an important demonstration role in the harmless treatment of domestic waste incineration fly ash in China (Ministry of Housing and Urban-Rural Development Construction Industry Scientific and Technological Achievements Evaluation Certificate, Jian Ke Ping [2011] No. 043). Application situation or prospects: Suitable for heavy metal stabilization treatment of dry and semi-dry flue gas purification system fly ash from domestic waste incineration plants. The treated product can meet the entry requirements for sanitary landfills. This technology is also applicable to the stabilization treatment of pollutants such as flue gas purification system fly ash from hazardous waste incineration, heavy metal-contaminated hazardous waste, and industrial sludge. Based on an authorized invention patent process, through key equipment selection improvement, Design and operation parameter optimization have been achieved for the chemical stabilization treatment technology of incineration fly ash under the background of China's domestic household waste composition (Changzhou Domestic Waste Incineration Power Plant Fly Ash Stabilization Treatment), with a scale reaching 800t/d equivalent to incinerated garbage, becoming the first national standard application example after its promulgation in China. The demonstration project has been stably operating for 30 months to date, treating 25,000 tons of fly ash. In July 2010, it was listed as one of Jiangsu Province's first batch of "Jiangsu Urban Construction Demonstration Projects." On July 2, 2011, it passed the result evaluation organized by the Science and Technology Development Promotion Center of the Ministry of Housing and Urban-Rural Development (Jian Ke Ping [2011] No. 043). In March 2012, it received the Second Prize for Technological Invention of the Ministry of Education for the year 2011.