Study on the Uniformity of Secondary Air of a 660 MW Ultra-Supercritical CFB Boiler

Based on the field test of a 600 MW supercritical circulating-fluidized bed boiler, this paper optimizes secondary air pipe layout scheme 660 ultra-supercritical circulating fluidized boiler with similar furnace structure and carried out numerical simulation its distribution uniformity. The box adopts variable section design, branch separate inlet mode. experimental results showed that oxygen concentration was uniform near rear wall, but all exhibited “decrease–increase–decrease” profile along horizontal line, which indicated trajectory jet first in shape bending downward then upward. To achieve more for CFB boilers, further optimization bellows pipes should be considered. Numerical deviation rate internal lower reached 17%, there space boiler. Its uniformity can increased by adding valves other measures. velocity within 3% means supply diameter change, better achieved to reduce speed adjusting combustion.