Four-section type steam air preheater drainage system

Abstract

The invention relates to the field of municipal solid waste incineration, in particular to a four-section type steam air preheater drainage system for heating garbage incinerator combustion air. The four-section type steam air preheater is sequentially provided with a low-pressure supercooling section heat exchanger (4), a high-pressure supercooling section heat exchanger (3), a low-pressure condensation section heat exchanger (2) and a high-pressure condensation section heat exchanger (1) according to an air flow direction, steam pocket extracted steam enters the high-pressure condensation section heat exchanger (1) for heat exchange, then enters the high-pressure supercooling section heat exchanger (3) and finally enters a drain pipeline, steam turbine extracted steam passes through thelow-pressure condensation section heat exchanger (2) for heat exchange, then enters the low-pressure supercooling section heat exchanger (4) and finally enters the drain pipeline, and a drain regulating valve is used for regulating the drain flow through a buffer tank liquid level signal so as to ensure the heat exchange capacity and the extracted steam heat utilization rate and enable the systemto safely and stably operate for a long time.

Description

technical field [0001] The invention relates to the field of municipal solid waste incineration, in particular to a four-stage steam air preheater drainage system for heating the combustion air of a waste incinerator. Background technique [0002] At present, the primary air of waste incineration plants is heated by steam air preheaters. In order to improve the heat utilization rate of extraction steam and solve problems such as pipeline vibration and deaerator boiling, four-stage steam air preheaters are used more and more. The four-stage steam air preheater adds a low-pressure subcooling section heat exchanger and a high-pressure subcooling section heat exchanger to further reduce the temperature of the saturated water from the high-pressure condensing section heat exchanger and the low-pressure condensing section heat exchanger to 90~ 120°C. The heat exchange capacity of the four-stage steam-air preheater and the heat utilization rate of extraction steam largely depend o...

AI Technical Summary

Problems solved by technology

The heat transfer capacity of the four-stage steam-air preheater and the heat utilization rate of extraction steam largely depend on the reliability and rationality of the drainage system. Conventional inverted bucket traps and gas-liquid two-phase flow traps have different degrees of drainage with steam , unable to stably maintain the pressure inside the heat exchanger tube and easily damaged

The problem of the drainage system will also cause a series of problems such as the failure of the steam air preheater to heat the air to the design temperature, the extraction steam flow rate is higher than the design value, and the deaerator boils

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