Medium/low-temperature smoke double circulation device for preventing high-alkali coals from slagging and method thereof

Abstract

The invention discloses a medium / low-temperature smoke double circulation device for preventing a high-alkali coal boiler from slagging and a method thereof. The device comprises a boiler hearth, a tail flue, a horizontal flue, a low-temperature smoke recirculation flue and a medium-temperature smoke recirculation flue; less medium-temperature smoke is selected in a tail flue area behind a dust remover, and is ejected into the hearth through a medium-temperature circulation smoke inlet at the bottom of the hearth; and less low-temperature smoke is selected, and is ejected to a hearth outlet through a low-temperature circulation smoke inlet at the upper end of the hearth outlet. The device can effectively reduce and control the temperature of the hearth outlet and the concentration of alkali metal in smoke in the hearth outlet; circulating smoke achieves a scouring effect on such heated surfaces as a superheater; and the temperature of the hearth can be effectively controlled, so that the temperature of the hearth outlet is controlled, the slagging, dirt staining and dust accumulation conditions of heated surfaces of the horizontal flue and the tail flue can be greatly relieved, andthe full-load, safe and stable operation of the boiler can be guaranteed when high-sodium metal coals are burnt.

Description

technical field [0001] The invention relates to a medium and low temperature flue gas double circulation device and method for preventing slagging of high-alkali coal boilers. Background technique [0002] Coal has always been an important pillar of energy in our country. For a long time, thermal power generation based on coal will be the main source of electricity in our country. my country has a large amount of high-alkali metal coal, and the Zhundong coalfield reserve in the Jungar Basin in Xinjiang is estimated to have 390 billion tons, which is enough for China to use for a century. However, Zhundong coal with high alkali metal content will produce serious slagging behavior in the actual power plant boiler combustion, and boiler ash accumulation and slagging will seriously threaten the safe and stable operation of power plant boilers. The reasons for boiler soot and slagging are very complicated, and are closely related to boiler structure, chemical characteristics of ...

AI Technical Summary

Problems solved by technology

In order to be able to utilize high-alkali metal coal such as Zhundong coal, domestic power plants adopt low-load operation and mixed-fired other coal types. In this way, the utilization efficiency of Zhundong high-alkali coal is very low

Images