Method of supercritical once-through boiler for achieving stable-pressure pipe blowing in wet state

Abstract

The invention discloses a method of a supercritical once-through boiler for achieving stable-pressure pipe blowing in a wet state. The method comprises the steps that 1, a temporary system pipeline is set up; 2, powder feeding and pipe blowing are carried out on the supercritical once-through boiler; 3, the fineness of coal powder is adjusted, and the fineness R90 of the coal powder is smaller than 5%; and 4, a boiler desuperheating water system, a smoke baffle and the total air volume are adjusted so that the steam temperature of a high-temperature superheater outlet can be smaller than or equal to 427 DEG C, the steam temperature of a high-temperature reheater outlet can be smaller than or equal to 460 DEG C, and the supercritical once-through boiler can achieve stable-pressure pipe blowing in the wet state. The technical problems that in the prior art, the procedure of stable-pressure pipe blowing of the supercritical once-through boiler in a dry state is complex, pipe blowing time is long, the dry state and the wet state need to be switched, the safety risk of a water cooling wall is large, and a temporary system is high in cost are solved.

Description

technical field [0001] The invention belongs to the pipe blowing technology of a supercritical once-through boiler in a thermal power plant, and in particular relates to a method for realizing a pressure-stabilizing blowpipe of a supercritical once-through boiler in a wet state. Background technique [0002] The blowpipe of a supercritical once-through boiler is an important part of the infrastructure construction of a thermal power plant. The quality of the blowpipe directly affects the safe operation of the unit, especially the steam turbine. [0003] At present, the supercritical once-through boiler pressure-stabilizing blowpipe technology is carried out when the once-through boiler turns dry. When the once-stabilizing blowpipe is completed, the boiler must be shut down to cool down. Through thermal expansion and contraction, the scale on the heating surface is easy to fall off. , therefore, the boiler must return to the wet state after the dry blowpipe ends. The automat...

AI Technical Summary

Problems solved by technology

[0004] The technical problem to be solved by the present invention is to provide a method for the supercritical once-through boiler to realize the steady-pressure blowpipe in the wet state, so as to solve the complex blowpipe process of the supercritical once-through boiler in the dry state in the prior art. Conversion, high safety risk of water wall, high cost of temporary system piping and other technical problems