Ultralow-load combustion stabilizing system for improving boiler combustion characteristics of thermal power generating unit

Abstract

The invention discloses a combustion stabilizing system for a thermal power generating unit boiler under the ultralow load. The combustion stabilizing system comprises a coal feeder communicating with a raw coal bunker, the output end of the coal feeder is sequentially connected with a downstream drying pipe, a coal mill, a coarse pulverized coal separator, a fine pulverized coal separator, a coal bucket and a main combustor of the boiler, an air pre-heater communicates with the coal mill, an after-combustion air chamber arranged on the top of the boiler and a hot primary air duct, and the hot primary air duct communicates with the input end of the downstream drying pipe, a secondary air box, a pulverized coal exhauster and the fine pulverized coal separator. The combustion stabilizing system is characterized by further comprising a pulverized coal air source mixer connected with a combustion stabilizing air source system, the input end of the pulverized coal air source mixer is connected with a pipeline between the pulverized coal exhauster and the main combustor, and the output end of the pulverized coal air source mixer is connected with the main combustor. According to the system, the combustion stabilizing air source system and the pulverized coal air source mixer are additionally arranged in an original thermal power generating unit boiler system for an original pulverized coal producing system and combustion system to stabilize combustion of the boiler under the ultralow load, and then the safety of the boiler under the low load is guaranteed.

Description

technical field [0001] The invention relates to a technology for stabilizing combustion of thermal power unit boilers under ultra-low load, which is used to stabilize the combustion of boilers when thermal power units operate at ultra-low loads, thereby improving the safe and stable operation capability of power plant units under ultra-low loads , to ensure the safety of the unit boiler, belonging to the technical field of power stations. Background technique [0002] In recent years, the installed capacity of renewable energy such as wind power and photovoltaic power generation in my country has grown rapidly. As of 2015, the total installed capacity of wind power reached 129 million kilowatts, and the total installed capacity of photovoltaic power generation reached 41.58 million kilowatts. However, the current regulation capacity of my country's power system is difficult to meet the large-scale development and complete consumption of these clean energies, which has led t...

AI Technical Summary

Problems solved by technology

Under the ultra-low load of the whole system, the temperature of the furnace will drop sharply, which will make it difficult for the pulverized coal to ignite quickly, which will lead to poor flame stability, easy flameout, and major safety hazards such as furnace fire extinguishing and blasting.

At present, the unit system can only maintain stable combustion without oil injection under the load of 30% BMCR or 35% BMCR, and cannot meet the technical requirements of ultra-low load (20% BMCR) without oil injection and stable combustion

Images