Self-variable-resistance blast cap

Abstract

The invention provides a self-variable-resistance blast cap. A movable rod is arranged in a limit hole, size of a gap between the movable rod and the limit hole can be changed when primary air is introduced, during operation under low load, the air volume of introduced primary air is relatively small, at the moment, the gap between the movable rod and the limit hole is relatively small, resistanceproduced when air flow flows through is relatively large, and therefore, uniform air distribution of multiple blast caps when air volume is small is realized; and during operation under high load, the air volume of the introduced primary air is relatively large, at the moment, the gap between the movable rod and the limit hole is relatively large, and resistance produced when air flow flows through becomes small, so that energy consumption of a draught fan during operation under high load is reduced. Uniform air distribution with small air volume under low load can be realized, oxygen contentis reduced, and NOx emission is reduced; uniform air distribution with large air volume and small resistance under high load can be realized, energy consumption of the draught fan is reduced, and boiler efficiency is improved; and besides, the problem of contradiction between low-load material fluidifying uniformity (blast cap resistance) and the oxygen content is solved, and the problems of toolarge resistance and too high energy consumption under high load are solved.

Description

technical field [0001] The invention belongs to the field of circulating fluidized bed boilers, in particular to an air cap with self-variable resistance. Background technique [0002] The resistance and structural form of the air distribution plate hood of circulating fluidized bed boilers have a great influence on the fluidization of bed material and the economical efficiency of boiler operation. Appropriate resistance can make the air volume distribution through the air cap uniform, so that the fluidization in the furnace can be uniform, and local poor fluidization and high temperature phenomena can be avoided; from the perspective of fluidization air distribution uniformity, the greater the resistance, the more suitable, but the greater the resistance , the greater the primary wind pressure loss, the greater the current of the primary fan, and the greater the energy consumption of the boiler operation. [0003] At present, the design of the conventional hood is fixed st...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to provide a self-variable resistance air cap, which solves the problem that the current air cap cannot well solve the problem of low-load material fluidization uniformity (air cap resistance) and oxygen excess

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