Technology for Addressing Excessive Peroxide Scale Blockage in Thermal Power Units Without Pipe Cutting

Regarding the problem of excessive temperature on the tube walls caused by the oxidation scale shedding and blockage in the high-temperature superheater during the startup stage of supercritical thermal power units, this article takes the 350 MW supercritical direct-fired boiler of Unit 1 of a certain power plant as an engineering example, and studies and applies two non-cutting pipe treatment technologies: high-pressure large-flow disturbance flushing and load reduction shutdown sedimentation and redistribution. It also provides optimized operation control strategies. Based on the analysis of the generation, shedding and blockage mechanism of the oxidation scale, the operating parameters are optimized in combination with the boiler blowing management theory. The applicability and economy of the two technologies are compared. The results show that high-pressure large-flow disturbance flushing combined with refined operation can quickly eliminate moderate blockages; the shutdown sedimentation and redistribution technology can solve severe blockages through the fragmentation of the oxidation scale and the reconfiguration of the position. Both methods avoid the drawbacks of traditional shutdown pipe cutting treatment, reduce the processing cost by more than 90%, significantly shorten the shutdown time, and can provide a safe and efficient engineering reference for the oxidation scale blockage treatment of similar supercritical units.