Steam extraction and heating integrated system for electric peak-load shaving of combined cycle unit and operation method of steam extraction and heating integrated system

Abstract

The invention relates to a steam extraction and heating integrated system for electric peak-load shaving of a combined cycle unit and an operation method of the steam extraction and heating integratedsystem. The steam extraction and heating integrated system comprises a gas turbine unit and a steam turbine unit, integrated design of different steam extraction modes is carried out based on the principle of gradient energy utilization, and thus the thermoelectric decoupling operation capacity of the combined cycle unit is effectively improved, and heating requirements of residents are met; in addition, hot water heat storage systems are simultaneously coupled in a heating system and a boiler water feeding system, so that cooperative matching of electric peak-load shaving and heating of thecombined cycle unit is achieved, and the electric peak-load shaving capacity of the combined cycle unit during operation under a pure-condensation condition is improved. By means of the steam extraction and heating integrated system, loss of working capacity in the heating process is effectively lowered while outward heating capacity of the combined cycle unit is deeply exerted. Especially currentsevere electric peak-load shaving policy requirements are met, the deep peak-load shaving capacity of a thermal power generating unit is achieved, the requirement of a power grid for unit peak-load shaving is truly met, and high practical application value is achieved.

Description

technical field [0001] The invention belongs to the technical field of cogeneration of heat and power, and in particular relates to an integrated steam extraction and heat supply system for power peak regulation of a 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 heat...

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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