CN-224228733-U - Solid heat storage peak shaving system of thermal power plant

CN224228733UCN 224228733 UCN224228733 UCN 224228733UCN-224228733-U

Abstract

The utility model relates to a solid heat storage peak regulation system of a thermal power plant, which comprises a boiler, a reheater, a steam turbine power generation system with multi-stage extraction steam, a solid heat storage device, a heat exchanger, a steam pressurizing device and a heat pump, wherein one part of main steam enters a high-pressure cylinder of the steam turbine power generation system with multi-stage extraction steam, the other part of main steam enters the solid heat storage device through a first main steam bypass to store heat, condensed low-temperature water exchanges heat with reheat steam output by the reheater in the heat exchanger to heat up to form high-temperature water, the high-temperature water returns to the water supply position of the boiler, reheat steam exchanges heat to form reheat steam with low superheat degree, and the reheat steam enters the steam pressurizing device to be pressurized and then returns to the inlet position of the reheat steam cold end of the boiler. The system is simple, the operation principle and control logic of the original power plant are not changed basically, the cost is low, the thermodynamic system balance is good, and the thermal power unit can be started and stopped quickly and can carry out deep peak shaving.

Inventors

LI WEI
RUAN YANG

Assignees

北京兆阳光热技术有限公司

Dates

Publication Date: 20260512
Application Date: 20250507

Claims (9)

1. The utility model provides a solid heat-retaining peak regulation system of thermal power plant, includes boiler, reheater, has the steam turbine power generation system of multistage extraction of steam, its characterized in that still includes solid heat storage device, heat exchanger, the boiler output main steam, a portion main steam gets into the high-pressure jar of the steam turbine power generation system of multistage extraction of steam, another portion main steam gets into through first main steam bypass in the solid heat storage device carries out the heat accumulation, and the low temperature water after the condensation is pressurized carries out heat transfer with the reheat steam of reheater output and intensifies and form high temperature water in the heat exchanger, high temperature water returns to the water supply department of boiler, form low superheat degree reheat steam after the reheat steam heat transfer, get into in the steam supercharging device and carry out the pressure boost, then return to the steam cold junction entrance of boiler.
2. The solid heat storage peak shaving system of a thermal power plant according to claim 1, wherein the steam supercharging device is an electrically driven steam supercharging device or a steam ejector.
3. The solid heat storage peak shaving system of a thermal power plant according to claim 1, wherein the solid heat storage device comprises a superheated solid heat storage device and an evaporated solid heat storage device, the main steam enters the evaporated solid heat storage device through a first main steam bypass, the reheat steam firstly enters the superheated solid heat storage device to store heat, and the cooled reheat steam enters a heat exchanger to further release heat.
4. The solid heat storage peak shaving system of a thermal power plant according to claim 2, wherein medium-pressure steam provided by the main steam or the steam turbine generator system for multi-stage steam extraction enters a first inlet of the steam ejector, low-superheat reheat steam enters a second inlet of the steam ejector, steam boosting is achieved after the low-superheat reheat steam passes through the steam ejector, and the boosted steam enters an inlet of a reheat steam cold end of the boiler and/or an industrial steam end.
5. The solid heat storage peak shaving system of the thermal power plant according to claim 1, wherein the deaerator is arranged in the turbine power generation system with the multi-stage extraction, and a water supplementing pipeline is further arranged at the front end of the deaerator in the turbine power generation system with the multi-stage extraction.
6. The solid heat storage peak shaving system of a thermal power plant according to claim 1, wherein the solid heat storage device comprises a solid heat storage medium and a heat exchange channel.
7. The solid heat storage peak shaving system of a thermal power plant according to claim 1, wherein the steam turbine power generation system with multi-stage extraction is provided with a deaerator, a heat taking inlet of the solid heat storage device is connected with a deaerator rear pressurizing water feeding pump in the steam turbine power generation system with multi-stage extraction, and hot water obtained by pressurizing and heating deaerated water output by the deaerator in the steam turbine power generation system with multi-stage extraction enters a water feeding position of the boiler.
8. The solid heat storage peak shaving system of the thermal power plant according to claim 1, wherein the steam turbine power generation system with the multi-stage extraction steam is provided with a deaerator, a heat taking inlet of the solid heat storage device is connected with a deaerator rear pressurizing feed water pump in the steam turbine power generation system with the multi-stage extraction steam, and steam obtained by pressurizing and heating deaerated water output by the deaerator in the steam turbine power generation system with the multi-stage extraction steam enters an inlet of a reheat steam cold end of the boiler or an industrial steam end.
9. The solid heat storage peak shaving system of a thermal power plant according to claim 1, wherein a heat taking inlet of the solid heat storage device is connected with a separate deaerator, a separate pressurizing water feeding pump is arranged between the solid heat storage device and the separate deaerator, and steam obtained after the deoxidized water output by the separate deaerator is pressurized and heated enters an industrial steam end.

Description

Solid heat storage peak shaving system of thermal power plant Technical Field The utility model relates to a thermal power plant peak shaving system, in particular to a system for carrying out deep peak shaving on a thermal power plant by adopting solid heat storage. Background In an electric power system, the balance between an electricity utilization end and a power generation end is important. The traditional power system mainly uses thermal power, and when the electricity consumption fluctuates, the balance of the seesaw is kept by adjusting the generated energy. However, as the proportion of new energy power generation increases, there is a mismatch between the fluctuation of the power consumption and the power generation, so that the balance of the power system is challenging. The installed capacity of new energy increases year by year, the power generation characteristic of new energy is different from that of thermal power, and the new energy is affected by weather, so that the power generation capacity is difficult to control accurately. This results in that when the power consumption decreases, the "large fat" (thermal power generating unit) originally used for balancing cannot timely reduce the power generation amount, so that the balance of the power system is difficult to maintain. In order to maintain the stability of the power system, the "minimum output" of the thermal power generating unit is required to be lowered to a lower level to accommodate the small change in the power consumption. However, the flexible retrofitting of thermal power plants is not easy. Prior to retrofitting, the minimum technical output of the thermal power plant is typically between 45% and 50%, below which a stable combustion of the boiler at low load may be affected. After modification, the minimum technical output can be reduced to 30% or even lower, but the increase in fuel cost at the time of deep peak shaving needs to be considered. At present, a heat storage system is adopted to realize deep peak shaving of a thermal power plant, which is a very direct and effective means. The cost of solid heat storage is relatively low, but when the solid heat storage is adopted to carry out deep peak shaving of the thermal power plant, the balance and high efficiency of the whole thermodynamic system are required to be considered in a refined mode, and the working flow and basic logic of the original steam turbine generator unit system are not changed. Therefore, it is especially important to develop a thermal power plant deep peak regulation system with low cost, good thermodynamic system balance and high efficiency. Disclosure of utility model The utility model aims to provide a solid heat storage peak regulation system of a thermal power plant, which comprises a boiler, a reheater, a steam turbine power generation system with multi-stage extraction steam and a solid heat storage device, and is characterized by further comprising a heat exchanger, wherein the boiler outputs main steam, one part of the main steam enters a high-pressure cylinder of the steam turbine power generation system with multi-stage extraction steam, the other part of the main steam enters the solid heat storage device through a first main steam bypass to store heat, condensed low-temperature water exchanges heat with reheat steam output by the reheater in the heat exchanger to heat up to form high-temperature water, the high-temperature water returns to the water supply position of the boiler, reheat steam forms reheat steam with low superheat degree after heat exchange, enters a steam supercharging device to carry out supercharging, and then returns to the inlet position of the reheat steam cold end of the boiler. Preferably, the steam pressurizing device is an electrically driven steam pressurizing device or a steam ejector, for example, the pressure of the low-temperature low-pressure steam is increased after the low-temperature low-pressure steam passes through the electrically driven steam pressurizing device or the steam ejector, and the low-temperature low-pressure steam returns to the reheat steam system again, so that the balance relation between the boiler and the reheat system is maintained. Preferably, the solid heat storage device comprises an overheat solid heat storage device and an evaporation solid heat storage device, the main steam enters the evaporation solid heat storage device through a first main steam bypass, the reheat steam firstly stores heat in the overheat solid heat storage device before exchanging heat by the heat exchanger, and then enters the heat exchanger to further release heat after cooling. Preferably, the medium-pressure steam provided by the main steam or the steam turbine generator system for multi-stage steam extraction enters a first inlet of the steam ejector, the low-superheat reheat steam enters a second inlet of the steam ejector, the low-superheat reheat steam passes through the steam ejector to reali