Desulfurize flue gas waste heat recovery system used in fire coal electric generating set

Abstract

The invention discloses a desulfurization flue gas waste heat recovery system for a coal-fired generator set, which comprises at least a gas-water heat exchanger for exchanging heat energy between gas state and liquid state, a flue gas inlet channel and a flue gas outlet channel respectively independently communicated with the gas-water heat exchanger, and a condensation water inlet pipeline and a condensation water outlet pipeline; a flue gas inlet of the gas-water heat exchanger is communicated with a rear flue gas channel of a boiler flue gas dust remover in the coal-fired generator set; a flue gas outlet of the gas-water heat exchanger is communicated with the flue gas inlet of a desulfurization absorption tower in a desulfurization system; a condensation water inlet and a condensation water outlet of the gas-water heat exchanger can be in sereies or parallel with at least a first-stage low-pressure heater of a regenerative system. The desulfurization flue gas waste heat recovery system provided in the invention has the advantages of the high waste heat utilization ratio, saving energy and water, the obvious discharge reducing benefit and the high comprehensive utilization degree of abandoned resources.

Description

technical field [0001] The invention relates to the field of coal-fired generating sets, in particular to a desulfurization flue gas waste heat recovery system applied to coal-fired generating sets. Background technique [0002] At present, my country's power supply situation is very tight, and the installed capacity is also increasing rapidly year by year. Although a large number of desulfurization devices are under construction, according to the current emission control level, by 2020, China's thermal power plants will emit SO 2 Will reach more than 21 million tons. If the air pollutants emitted by thermal power plants are not effectively controlled, it will directly affect the improvement of China's air environment quality and the sustainable development of the power industry. The fundamental way to control sulfur dioxide in thermal power plants is flue gas desulfurization. It should be noted that the effectiveness of desulfurization in coal-fired thermal power plants ...

AI Technical Summary

Problems solved by technology

[0013] (1) The residual heat of the flue gas has not been utilized at all, and the temperature of the flue gas entering the desulfurization tower is much higher than its allowable working temperature. This can only be done by spraying a large amount of water to cool it down, resulting in a sharp increase in water consumption. Two 1000MW units Monthly increase 2×63T / h

[0014] (2) The evaporated water vapor increases the flue gas volume by more than 30%, which makes the resistance loss of the desulfurization tower and subsequent flue and chimney significantly increase (about 70% more)

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