Abstract: The imported grate furnace of a domestic waste incineration project was designed with insulated furnace wall, and the coking problem was serious during operation. Through characterization analysis, it was found that calcium feldspar was the main component of the coke block, which was easy to form low-temperature eutectic mixture. When the furnace temperature was too high, the ash particles generated by incineration were prone to softening and melting, and adhered to the furnace surface with high temperature to form coke blocks. To solve the problem, the project modularized the side wall of the original furnace, making each section of the furnace wall enclosed and independent. In the local high-temperature area, the original insulated furnace wall was transformed into the air-cooled wall to reduce the temperature. After the renovation, the coking problem has been significantly improved, enhancing the safety and stability of the incinerator operation, improving the furnace thermal efficiency, and saving the operating costs. The project renovation has achieved expected results.

Key words: imported grate furnace, coking, low-temperature eutectic mixture, air-cooled wall