Abstract: In order to determine the best burning condition, by analyzing the one-month running data of a 1 036-MW unit in a power plant, it is discovered that the CO content in the flue gas is too high under high load conditions and the maximum fluctuation of the boiler efficiency is 0.6% at rated load, which leads to the increase of the coal consumption and affects the safe operation of the boiler. In boilers firing pulverized coal or mixed coal, the change of the combustion state easily causes unstable combustion, large parameter variation and boiler efficiency reduction. By analyzing the combustion characteristic curve, this paper attempts to optimize the burning conditions with the counterbalance calculation method the burning control technology and the self-adaptive optimization control technology to maximize the boiler efficiency and minimize the coal consumption at different loads.

Key words: ultra supercritical boiler, combustion, efficiency, O2, the concentration of CO, incomplete combustion loss