Heat supply and electric power peak regulation coupling system used for gas-steam combined cycle unit and operation method of heat supply and electric power peak regulation coupling system

Abstract

The invention relates to a heat supply and electric power peak regulation coupling system used for a gas-steam combined cycle unit and an operation method of the heat supply and electric power peak regulation coupling system, and belongs to the technical field of improvement of flexibility of thermoelectric units. The heat supply and electric power peak regulation coupling system comprises a gas turbine unit and a steam turbine unit. The gas turbine unit comprises a gas turbine gas compressor, a gas turbine combustion chamber, a gas turbine and a first generator. The steam turbine unit comprises a waste heat boiler, a steam turbine high-pressure cylinder, a steam turbine intermediate-pressure cylinder, a steam turbine low-pressure cylinder, a second generator, a condenser, a condensation water pump, a make-up pump, a shaft seal heater, a deaerator, a first temperature and pressure reduction device, an evaporation heat exchanger, a pressure matcher, a second temperature and pressure reduction device, a steam heat accumulator and a third temperature and pressure reduction device. By means of the heat supply and electric power peak regulation coupling system, the external heat supplycapacity of the combined cycle unit is deeply excavated, and meanwhile acting capacity losses in the heat supply process are effectively reduced; and the current rigorous electric power peak regulation policy requirement is met, and the deep peak regulation capacity of a thermal power generating unit is achieved.

Description

technical field [0001] The invention belongs to the technical field of improving the flexibility of thermoelectric units, and in particular relates to a heating and power peak-shaving coupling system for a gas-steam combined cycle unit and an operating method thereof. Background technique [0002] At present, my country's policies are gradually emphasizing the promotion of new energy sources and reducing the proportion of thermal power units, which makes the development of thermal power units face severe challenges. At present, in order to improve the comprehensive energy utilization efficiency of thermal power units and strive for more utilization hours of power generation, deeply excavating the heating capacity of thermal power units has attracted more and more attention from all walks of life. Gas-fired cogeneration is a form of energy utilization that produces heat and electricity at the same time. It uses high-grade heat for power generation and low-grade heat for heati...

AI Technical Summary

Problems solved by technology

[0003] At present, the main problem faced by the central heating system of gas-fired cogeneration is that the heat-to-power ratio is low. The heat-to-power ratio generated by conventional gas-fired cogeneration combinations has certain limitations. The smaller it is, taking a 100,000 kW unit as an example, its heat-to-electricity ratio is about 0.7

Especially in the face of the current severe situation of deep peak regulation of thermal power, the units often operate under low load conditions. At this time, the external heating capacity of the units is lower, which has a serious impact on the safety of heating supply.

However, the existing technology such as the patent "A Combined Cycle Heat and Power Cogeneration System (Patent No. 201310401252.0)" is to use high exhaust steam extraction to reduce temperature and reduce pressure to supply heat to the outside. The technical defects are: (1) No consideration of energy The cascade utilization of direct temperature reduction and pressure reduction has a large loss of working capacity; (2) The need for deep peak regulation of thermal power is not considered. In order to meet the external heat supply, the unit needs to operate at a high load, and the peak regulation capacity of the unit is poor

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