Operational Issues and Retrofit of a Low-Rate Intermediate-Temperature Separated Pulverized Coal Circulating Fluidized Bed Boiler
Abstract：This paper analyzes the operational issues encountered during the operation of a 2×130 t/h low-rate intermediate-temperature separated pulverized coal circulating fluidized bed boiler in a thermal power plant, including heat transfer surface wear and tube burst, difficulty in increasing load, excessive nitrogen oxide emissions, and ash accumulation on the rear heat transfer surfaces. Operational adjustments and technical retrofit measures were implemented. The results show that methods such as installing anti-wear protective plates, metal spraying for anti-wear, welding repair, sealing, and reducing the furnace operating differential pressure can reduce the risk of tube bundle bursting during operation. By adjusting the coal ash content through fuel blending, the boiler load can be increased to 120-125 t/h. Combining low-oxygen combustion inside the furnace with SNCR-SCR denitrification technology ensures normal compliance with nitrogen oxide emissions, reduces denitrification agent consumption by 86%, and avoids ammonia slip and blockage and corrosion of the rear air preheater. Using porcelain tubes combined with an impulse soot blower effectively solves the problem of air preheater ash accumulation and blockage, achieving long-term stable operation of the boiler.
Keywords：Intermediate temperature separation%Circulating fluidized bed boiler%Nitrogen oxides
Publication Date：2025-08-30
Online Publishing Date：2025-10-22(First online date of this platform, not the publication date of the document)
Pages：3( 82-84 )