Fuel coal decarburization and waste heat utilization power generation system integrating supercritical carbon dioxide and heat pump

Abstract

The invention discloses a fuel coal decarburization and waste heat utilization power generation system integrating supercritical carbon dioxide and a heat pump in the technical field of power stationdecarburization and energy-saving technologies. The system mainly comprises a fire coal power generation subsystem, a decarburization subsystem and a carbon dioxide circulating power generation subsystem. In order to reduce the heat loss of the decarburization system and improve the power generation efficiency of a decarburization fuel coal power station, the following optimal steps are carried out: (1) by using the supercritical carbon dioxide as heat absorbing working medium, the waste heat in the decarburization process and the degree of superheat of the steam extraction for decarburizationare sequentially absorbed according to the heat grade, the carbon dioxide turbine power generation is driven, the effective work of the unit which is partially reduced due to the steam extraction fordecarburization is counteracted; (2) partial decarburization process waste heat is recycled by utilizing a second type absorption heat pump and partial steam extraction for decarburization is replaced to provide heat for a reboiler; (3) the carbon dioxide turbine exhaust is utilized to preheat the air, so that part of the higher-temperature flue gas is saved to heat the feed water, and the back heating and steam extraction of the steam turbine is reduced.

Description

technical field [0001] The invention belongs to the technical field of power plant decarbonization and energy saving, in particular to an integrated supercritical CO 2 and heat pump coal decarbonization and waste heat utilization power generation system. Background technique [0002] At present, China's coal-based primary energy and thermal power-based secondary energy structure have not changed. CO 2 Emissions are inevitable, and the accompanying greenhouse effect is becoming increasingly serious. To reduce CO 2 emissions, post-combustion decarbonization is widely regarded as a relatively mature technology with potential for large-scale application. At the same time, supercritical CO 2 Due to the characteristics of stable chemical properties, high density and low cost, working fluid has attracted more and more attention. Supercritical CO 2 Due to its good working fluid characteristics, the cycle has the advantages of simple system, compact equipment structure, and can...

AI Technical Summary

Problems solved by technology

[0003] The decarbonization process based on the MEA chemical absorption method consumes a lot of heat and releases a large amount of low-grade waste heat. Generally speaking, the heat required by the decarbonization unit is supplied by the extraction steam from the connecting pipe of the middle and low pressure cylinder of the steam turbine, which means that the decarbonization process will be Reduce the output of effective work of the system, resulting in a higher energy efficiency penalty, and have a certain impact on the safety of the low-pressure cylinder

Images