Waste heat boiler tail deoxidizing heat supply system

Abstract

The invention relates to a waste heat boiler tail deoxidizing heat supply system. The waste heat boiler tail deoxidizing heat supply system comprises a steam drum, a deoxidizing head which is fixed tothe top of the steam drum, a tail heating surface with an outlet connected with an inlet of the deoxidizing head, a second water feeding pump, an atmospheric type deaerator, a water-water heat exchanger and a first water feeding pump; an inlet of the tail heating surface is connected with an outlet of the second water feeding pump; a deoxidizing heat supply water outlet and a deoxidizing heat supply water inlet are formed in an outlet end of the tail heating surface; and the water-water heat exchanger is provided with a second water feeding inlet which is connected with a water feeding outletof the atmospheric type deaerator, a second water feeding outlet which is connected with an inlet of the water feeding pump, a first water feeding inlet which is connected with an outlet of the firstwater supply pump, and a first water feeding outlet which is connected with the water feeding inlet of the atmospheric type deaerator. According to the waste heat boiler tail deaeration heat supply system, the technical problems that the exhaust gas temperature is high, the corrosion is caused by high oxygen content of heat supply water, the potential safety hazard is brought to the operation ofa machine set and the output power of the machine set is reduced because the heating surface is in a dry-burning state under a non-heat supply working condition in the prior art are solved.

Description

technical field [0001] The invention relates to a heat supply system for removing oxygen at the tail of a waste heat boiler, and belongs to the technical field of power station boiler equipment. Background technique [0002] With the adjustment of the national energy structure, more and more newly-built gas-steam combined cycle units adopt the mode of "power determination by heat". It is no longer recovered, so the waste heat boiler needs a large amount of make-up feed water during operation. Supplementary feed water is usually chemically treated desalinated water. Since the oxygen content of desalinated water is much higher than the national standard for oxygen content of feed water (the oxygen content of feed water is less than 50ppb, and the oxygen content of steam is less than 7ppb), in order to solve the problem of deoxygenation of feed water , the existing solution is to add an atmospheric deaerator to the boiler tail deaeration heating system, as attached figure 1 A...

AI Technical Summary

Problems solved by technology

[0006] The present invention mainly solves the technical defects existing in the prior art that the energy efficiency of the boiler operation decreases due to less heat exchange between the tail heating surface and the flue gas, the hot water supply heating surface is prone to corrosion, and dry burning brings safety hazards to the unit, and provides a A waste heat boiler tail deoxygenation heating system with sufficient heat exchange between the heating surface at the tail and the flue gas, which can avoid corrosion or dry burning on the heating surface to ensure safe and reliable operation of the unit and high energy efficiency of the boiler operation

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