System and method for semi-coke blending combustion of coal-fired power plant with Brown gas for catalytic combustion supporting

Abstract

The invention discloses a system and a method for semi-coke blending combustion of a coal-fired power plant with Brown gas for catalytic combustion supporting. Low-rank coal pyrolysis semicoke and bituminous coal are subjected to mixed combustion, the Brown gas is distributed at a primary air nozzle in a sandwich air mode for catalytic combustion supporting on the semicoke, so that the problems that the semicoke is difficult to burn and poor in burnout performance can be effectively solved. Oxygen-rich air generated by a cryogenic air separation nitrogen making machine is preheated through smoke and then serves as oxygen-rich over-fire air, and the excess air coefficient of the main combustion area is controlled to be 0.8 or below, so that the reducibility of the main combustion area is enhanced, sufficient combustion of fuel can be guaranteed while NOx emission is effectively controlled, and the combustion efficiency of the boiler is improved. Flue gas and exhaust steam of a steam turbine are condensed through liquid nitrogen, equipment of the cryogenic air separation nitrogen making machine is heated through the flue gas in front of an air preheater, high-purity nitrogen can be made while moisture in the flue gas is collected and utilization of circulating cooling water of a power plant is reduced, and the efficiency of a boiler and the cryogenic air separation nitrogen making machine is improved.

Description

technical field [0001] The invention belongs to the technical field of power generation by pulverized coal furnaces in power stations, and in particular relates to a system and method for blending and burning semi-coke in coal-fired power stations with Brown gas catalytic combustion. Background technique [0002] According to the 2018 "World Energy Statistical Yearbook", in my country's energy consumption today, coal consumption has hit a record low, but it is still as high as 60.4%, indicating that my country's energy consumption is still dominated by coal for a long time. At present, my country's low-rank coal reserves are 500 billion tons, accounting for about 42% of the proven coal reserves. With the continuous development of my country's low-rank coal graded conversion industry, tens of millions of tons of semi-coke will be produced every year. As a carbon-based solid fuel, semi-coke has the characteristics of high ash content and low volatile content, which lead to it...

AI Technical Summary

Problems solved by technology

However, in the process of nitrogen production, some oxygen-enriched air with an oxygen concentration of about 35%

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