Air preheater arrangement structure of boiler

Abstract

The invention provides an air preheater arrangement structure of a boiler, which can satisfy the requirements on drying process when a powder processing system grinds brown coal, and simultaneously can ensure normal combustion and less coking in a combustion zone, thereby further solving the contradiction between the boiler drying process and the thermal efficiency of the boiler. The air preheater arrangement structure comprises an air preheater, a flue and a hot primary air flue, and is characterized in that the air preheater comprises a tubular air preheater and a rotary air preheater, the tubular air preheater is arranged above the rotary air preheater, the flue penetrates through the tubular air preheater and then is connected with a smoke inlet of the rotary air preheater, an inlet of the rotary air preheater is communicated with cold air, an air outlet of the rotary air preheater is connected with an air inlet of the tubular air preheater by the hot primary air flue, a secondary air outlet is arranged in the middle of the hot primary air flue and is communicated with the combustion zone, and a primary air outlet of the tubular air preheater is communicated with a dying zone of the powder processing system for grounding the brown coal.

Description

technical field [0001] The invention relates to the technical field of boiler structure, in particular to the layout structure of the air preheater of the boiler. Background technique [0002] The air preheater is a gas-gas heat exchanger that uses the heat of flue gas to heat the air required for boiler combustion. It is an important and indispensable part of power plant boilers. The main function of the air preheater is to heat the air required for combustion and reduce the exhaust gas temperature of the boiler to improve the thermal efficiency of the boiler. [0003] The existing air preheater layout structure converts cold air into hot air, and both the primary air and secondary air flow out from the outlet of the air preheater. The air temperature of the two is almost the same, but in practice, the primary air is used Satisfy the drying treatment when the pulverizing system grinds lignite. The secondary air is used for combustion in the combustion area. The air tempera...

AI Technical Summary

Problems solved by technology

[0003] The existing air preheater layout structure converts cold air into hot air, and both the primary air and secondary air flow out from the outlet of the air preheater. The air temperature of the two is almost the same, but in practice, the primary air is used Satisfy the drying treatment when the pulverizing system grinds lignite. The secondary air is used for combustion in the combustion area. The air temperature requirement of the primary air is higher than that of the secondary air. Once the air temperature of the secondary air is too high, it is easy to cause coking in the combustion area. , once the temperature of the primary air is too low, it is easy to cause poor drying treatment when the pulverizing system grinds lignite

To sum up, the existing air preheater layout structure cannot solve the contradiction between boiler drying treatment and boiler thermal efficiency

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