CN110863870A - A heat storage peak-shaving system and peak-shaving method based on a high-pressure heating circuit - Google Patents

Abstract

The invention discloses a thermocline layer heat storage peak regulation system and a peak regulation method based on a high-pressure heating circuit. The peak regulation system includes a heat storage module and a peak regulation module, and the peak regulation module includes a main circuit throttle valve and a bypass throttle. valve, the first molten salt pump, the second molten salt pump, the first molten salt valve, the second molten salt valve, the first steam valve and the second steam valve. The module changes the working state of the steam turbine, that is, the dynamic peak regulation is realized; the invention can improve the lifting and lowering load rate of the thermal power unit, improve the flexibility and economy of the unit, and has a simple structure and convenient operation.

Description

A heat storage peak-shaving system and peak-shaving method based on a high-pressure heating circuit

technical field

The invention relates to the technical field of thermal power generation, in particular to a thermocline layer heat storage peak regulation system and a peak regulation method based on a high-pressure heating circuit.

Background technique

At present, with the rapid development of my country's economy and the improvement of people's living standards, the demand for electricity is also increasing. Coal-fired generators in the power system have a large installed capacity. In order to cooperate with the integration of large-scale wind power, solar energy and other new energy power generation into the grid, as well as the changes in my country's power consumption structure, coal-fired generators will undertake more and more difficult peak shaving tasks. This puts forward higher requirements for the flexibility of coal-fired units, requiring them to be able to operate with large load changes and have a rapid load change rate. When the power grid requires rapid load changes, the internal heat storage capacity of the system is limited, and more potential heat storage systems are required to cooperate with traditional coal-fired units. The main constraints on the flexibility of thermal power units in my country are insufficient peak shaving capacity, slow load response speed, and significant impact on unit safety, environmental protection and economy. The technologies used to improve the flexibility of units at home and abroad mainly include: minimum stable combustion technology, heat storage tank thermal electrolytic coupling peak regulation technology, electric boiler thermal electrolytic coupling peak regulation technology, steam turbine bypass heat supply peak regulation technology, energy storage peak regulation technology technology, coordinated optimization control technology, etc.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a thermocline layer heat storage peak regulation system and a peak regulation method based on a high-pressure heating circuit, which can improve the lifting and lowering load rate of the thermal power unit, improve the flexibility and economy of the unit, and has a simple structure and convenient operation.

The technical scheme adopted in the present invention is:

A thermocline heat storage and peak regulation system based on a high-pressure heating circuit, including a boiler, a steam turbine, a condenser and a heat recovery system. Connected in sequence to form a loop, it also includes a heat storage module and a peak shaving module;

The steam turbine includes a high-pressure cylinder, a medium-pressure cylinder and a low-pressure cylinder. The new steam outlet of the boiler is connected to the inlet of the high-pressure cylinder, the exhaust steam of the high-pressure cylinder enters the boiler for reheating, the reheated steam outlet of the boiler is connected to the inlet of the medium-pressure cylinder, and the steam exhaust port of the medium-pressure cylinder is connected to the inlet of the medium-pressure cylinder. The inlet of the low-pressure cylinder, the exhaust port of the low-pressure cylinder is connected to the condenser;

The heat recovery system includes a low-pressure heat exchanger, a deaerator and a high-pressure heat exchanger which are connected in sequence through the main pipeline. The inlet of the low-pressure heat exchanger is connected to the condenser, and the outlet of the high-pressure heat exchanger is connected to the boiler inlet. The hot port is connected to the steam extraction port of the low pressure cylinder, the inlet of the deaerator is connected to the steam exhaust port of the medium pressure cylinder, and the heat exchange port of the high pressure heat exchanger is respectively connected to the steam extraction port of the medium pressure cylinder and the steam extraction port of the high pressure cylinder;

The heat storage system includes a water-molten salt heat exchanger, a molten salt tank, a steam-molten salt heat exchanger and a heat pump, and the molten salt tank is a single tank; the water-side inlet of the water-molten salt heat exchanger is connected to the deaerator outlet , the water side outlet of the water-molten salt heat exchanger is connected to the boiler inlet through the steam drum, the molten salt side inlet of the water-molten salt heat exchanger is connected to the top of the molten salt tank, and the molten salt side outlet of the water-molten salt heat exchanger is connected to the molten salt tank Bottom; the outlet of the molten salt side of the steam-molten salt heat exchanger is connected to the top of the molten salt tank, the inlet of the molten salt side of the steam-molten salt heat exchanger is connected to the bottom of the molten salt tank, and the outlet of the steam side of the steam-molten salt heat exchanger is connected through the steam drum The inlet of the boiler, the steam side inlet of the steam-molten salt heat exchanger is connected to the outlet of the heat pump; the primary inlet of the heat pump is connected to the new steam outlet of the boiler through the new steam bypass pipeline, and the secondary inlet of the heat pump is connected to the boiler reheated steam through the reheated steam bypass pipeline. Export;

The peak regulation module includes a main circuit throttle valve, a bypass throttle valve, a first molten salt pump, a second molten salt pump, a first molten salt valve, a second molten salt valve, a first steam valve and a second steam valve The main circuit throttle valve is set at the water supply pipeline at the outlet of the deaerator, the bypass throttle valve is set at the water side inlet of the water-molten salt heat exchanger, and the first molten salt pump and the first molten salt valve are set in sequence in At the entrance of the molten salt side of the water-molten salt heat exchanger, the second molten salt pump and the second molten salt valve are set in sequence at the entrance of the molten salt side of the steam-molten salt heat exchanger, and the first steam valve is set at the primary heat pump Between the inlet and the outlet of the fresh steam of the boiler, the second steam valve is arranged between the secondary inlet of the heat pump and the outlet of the reheated steam of the boiler.

Further, the heat pump adopts a jet heat pump.

A method for peak regulation using the above-mentioned high-pressure heating circuit-based thermocline heat storage peak regulation system, comprising the following steps:

A. Input the unit peak shaving target in the control center; the peak shaving target includes the peak shaving type and load adjustment target value;

B. According to the peak shaving target, the power state of the steam turbine is changed through the peak shaving module, that is, dynamic peak shaving is realized; the types of peak shaving include rapid load increase and rapid load reduction;

(a) The peak shaving process of rapidly increasing load is as follows:

a1: Open the first molten salt valve and the bypass throttle valve, the first molten salt pump works, and the second molten salt pump does not work;

a2: close the first steam valve, the second steam valve and the second molten salt valve;

a3: According to the load adjustment target value, the opening of the main circuit throttle valve is reduced, the main water supply at the outlet of the deaerator is reduced, the steam extraction volume of the high-pressure cylinder and the medium-pressure cylinder of the steam turbine is reduced, and more steam in the low-pressure cylinder returns to the condenser. , the turbine work increases;

a4: A part of the feed water at the outlet of the deaerator enters the water-molten salt heat exchanger for heating through the bypass throttle valve, and the heated water enters the steam drum;

a5: The hot molten salt at the top of the molten salt tank is driven by the first molten salt pump to release heat through the water-molten salt heat exchanger and then turns into cold molten salt and returns to the bottom of the molten salt tank;

(b) The peak shaving process for rapid load reduction is as follows:

b1: Open the first steam valve, the second steam valve, the second molten salt valve and the main circuit throttle valve, wherein the opening degrees of the first steam valve and the second steam valve are adjusted according to the load adjustment target value;

b2: close the first molten salt valve and the bypass throttle valve, the first molten salt pump does not work, and the second molten salt pump works;

b3: The new steam and reheated steam of the boiler enter the steam-molten salt heat exchanger through the heat pump for heat release, and the steam after releasing the heat enters the steam drum;

b4: The cold molten salt at the bottom of the molten salt tank is heated by the steam-molten salt heat exchanger under the driving of the second molten salt pump and then returned to the top of the molten salt tank to store heat as hot molten salt; The molten salt stores heat, reducing the work done by the steam turbine.

The present invention has the following beneficial effects:

(1) The peak shaving module is used to adjust the structure of the heat storage system under different working conditions, and the heat storage characteristics of the inclined temperature layer in the molten salt tank are used, that is, the upper layer is hot molten salt, and the lower layer is cold molten salt. The dynamic conversion of heat improves the lifting and lowering load rate of thermal power units, and improves the flexibility and economy of the unit. At the same time, it has the advantages of simple structure and cost saving;

(2) By adopting a jet heat pump, and designing the inlet steam of the jet heat pump to be the fresh steam and the reheated steam of the boiler, the temperature can be flexibly adjusted to reach the heating temperature required for the molten salt, and the flexibility of the present invention is further improved;

(3) By adjusting the different structures in the peak shaving module according to the load adjustment requirements, the peak shaving goals of rapid load increase and rapid load reduction can be achieved, the peak shaving efficiency is high, the flexibility is strong, and the energy generated by the system can be fully utilized to improve the present invention. economical.

Description of drawings

FIG. 1 is a schematic structural diagram of a peak regulation system in the present invention.

Description of reference numbers:

1. Heat pump; 1-1, primary inlet; 1-2, secondary inlet; 2, molten salt tank; 3, steam-molten salt heat exchanger; 3-1, steam side inlet of steam-molten salt heat exchanger; 3-2. The steam side outlet of the steam-molten salt heat exchanger; 3-3, the molten salt side outlet of the steam-molten salt heat exchanger; 3-4, the molten salt side inlet of the steam-molten salt heat exchanger; 4. Water - molten salt heat exchanger; 4-1, water-molten salt heat exchanger, molten salt side inlet; 4-2, water-molten salt heat exchanger, molten salt side outlet; 4-3, water-molten salt heat exchanger Water side outlet; 4-4, water side inlet of water-molten salt heat exchanger; 5, first molten salt pump; 6, second molten salt pump; 7, second steam valve; 8, first steam valve; 9 , the first molten salt valve; 10, the second molten salt valve; 11, the bypass throttle valve; 12, the condenser; 13, the steam drum; 14, the boiler; 15, the high pressure cylinder; 16, the medium pressure cylinder; 17 , low pressure cylinder; 18, deaerator; 19, main circuit throttle valve.

Detailed ways

As shown in FIG. 1 , the present invention includes a thermocline layer heat storage peak regulation system and a peak regulation method based on a high-pressure heating circuit.

The peak shaving system includes the boiler 14, the steam turbine, the condenser 12 and the regenerative system. The steam in the boiler 14 enters the steam turbine through the steam pipeline to do work. Thermal module and peak shaving module;

The steam turbine includes a high-pressure cylinder 15, a medium-pressure cylinder 16 and a low-pressure cylinder 17. The new steam outlet of the boiler 14 is connected to the inlet of the high-pressure cylinder 15, the exhaust steam from the high-pressure cylinder 15 enters the boiler 14 for reheating, and the reheated steam outlet of the boiler 14 is connected to the medium-pressure cylinder 16. The inlet, the exhaust port of the medium-pressure cylinder 16 is connected to the inlet of the low-pressure cylinder 17, and the exhaust port of the low-pressure cylinder 17 is connected to the condenser 12;

The heat recovery system includes a low-pressure heat exchanger, a deaerator 18 and a high-pressure heat exchanger connected in sequence through the main pipeline. The inlet of the low-pressure heat exchanger is connected to the condenser 12, and the outlet of the high-pressure heat exchanger is connected to the inlet of the boiler 14; The heat exchange port of the heat exchanger is connected to the steam extraction port of the low pressure cylinder 17, the inlet of the deaerator 18 is connected to the steam exhaust port of the medium pressure cylinder 16, and the heat exchange port of the high pressure heat exchanger is connected to the steam extraction port of the medium pressure cylinder 16 and the steam extraction port of the high pressure cylinder 15 respectively. ;

The heat storage system includes a water-molten salt heat exchanger 4, a molten salt tank 2, a steam-molten salt heat exchanger 3 and a heat pump 1, and the molten salt tank 2 is a single tank; the water-side inlet of the water-molten salt heat exchanger 4-4 is connected to the outlet of the deaerator 18, the water side outlet 4-3 of the water-molten salt heat exchanger is connected to the inlet of the boiler 14 through the steam drum 13, and the molten salt side inlet 4-1 of the water-molten salt heat exchanger is connected to the molten salt tank 2 The top, the molten salt side outlet 4-2 of the water-molten salt heat exchanger is connected to the bottom of the molten salt tank 2; the molten salt side outlet 3-3 of the steam-molten salt heat exchanger is connected to the top of the molten salt tank 2, and the steam-molten salt exchange The inlet 3-4 of the molten salt side of the heater is connected to the bottom of the molten salt tank 2, the outlet 3-2 of the steam side of the steam-molten salt heat exchanger is connected to the inlet of the boiler 14 through the steam drum 13, and the inlet 3-2 of the steam side of the steam-molten salt heat exchanger 1 is connected to the outlet of the heat pump 1; the primary inlet 1-1 of the heat pump 1 is connected to the fresh steam outlet of the boiler 14 through the new steam bypass pipeline, and the secondary inlet 1-2 of the heat pump 1 is connected to the reheat steam outlet of the boiler 14 through the reheat steam bypass pipeline ;

The peak regulation module includes a main circuit throttle valve 19, a bypass throttle valve 11, a first molten salt pump 5, a second molten salt pump 6, a first molten salt valve 9, a second molten salt valve 10, a first molten salt pump The steam valve 8 and the second steam valve 7; the main circuit throttle valve 19 is set at the outlet water supply pipeline of the deaerator 18, the bypass throttle valve 11 is set at the water side inlet of the water-molten salt heat exchanger 4, the first The molten salt pump 5 and the first molten salt valve 9 are sequentially arranged at the molten salt side inlet 4-1 of the water-molten salt heat exchanger, and the second molten salt pump 6 and the second molten salt valve 10 are sequentially arranged at the steam-molten salt side. At the inlet 3-4 on the molten salt side of the heat exchanger, the first steam valve 8 is arranged between the primary inlet 1-1 of the heat pump 1 and the new steam outlet of the boiler 14, and the second steam valve 7 is arranged at the secondary inlet 1-2 of the heat pump 1 Between the reheat steam outlet of the boiler 14.

Peak shaving methods include:

A. Input the unit peak shaving target in the control center; the peak shaving target includes the peak shaving type and load adjustment target value;

B. According to the peak shaving target, the power state of the steam turbine is changed through the peak shaving module, that is, dynamic peak shaving is realized; the types of peak shaving include rapid load increase and rapid load reduction;

(a) The peak shaving process of rapidly increasing load is as follows:

a1: Open the first molten salt valve 9 and the bypass throttle valve 11, the first molten salt pump 5 works, and the second molten salt pump 6 does not work;

a2: close the first steam valve 8, the second steam valve 7 and the second molten salt valve 10;

a3: Adjust the opening of the main circuit throttle valve 19 smaller according to the load adjustment target value, the main feed water volume at the outlet of the deaerator 18 is reduced, the steam extraction volume of the high-pressure cylinder 15 and the medium-pressure cylinder 16 of the steam turbine is reduced, and the low-pressure cylinder 17 has more steam to do work Returning to the condenser 12, the work done by the steam turbine increases;

a4: A part of the feed water at the outlet of the deaerator enters the water-molten salt heat exchanger 4 through the bypass throttle valve 11 for heating, and the heated water enters the steam drum 13;

a5: The hot molten salt at the top of the molten salt tank 2 turns into cold molten salt and returns to the bottom of the molten salt tank 2 after the first molten salt pump 5 is driven to release heat through the water-molten salt heat exchanger 4;

(b) The peak shaving process for rapid load reduction is as follows:

b1: Open the first steam valve 8, the second steam valve 7, the second molten salt valve 10 and the main circuit throttle valve 19, wherein the opening degrees of the first steam valve 8 and the second steam valve 7 are adjusted to the target value according to the load make adjustments;

b2: close the first molten salt valve 9 and the bypass throttle valve 11, the first molten salt pump 5 does not work, and the second molten salt pump 6 works;

b3: The new steam and reheated steam of the boiler 14 enter the steam-molten salt heat exchanger 3 through the heat pump 1 for heat release, and the steam after releasing the heat enters the steam drum 13;

b4: The cold molten salt at the bottom of the molten salt tank 2 is heated by the steam-molten salt heat exchanger 3 under the driving of the second molten salt pump 6 and then returns to the top of the molten salt tank 2 to store heat as hot molten salt; The reheated steam heats the molten salt and stores heat, which reduces the work done by the steam turbine.

In order to better understand the present invention, the technical solutions of the present invention are further described below with reference to the accompanying drawings.

As shown in Figure 1, the present invention discloses a thermocline layer heat storage and peak regulation system based on a high-pressure heating circuit, including a boiler 14, a steam turbine, a condenser 12, a heat recovery system, a heat storage module and a peak regulation module, and the boiler The steam in 14 enters the steam turbine to do work through the steam pipeline, and the boiler 14, the steam turbine, the condenser 12 and the heat recovery system are connected in sequence to form a loop.

The steam turbine includes a high-pressure cylinder 15, a medium-pressure cylinder 16 and a low-pressure cylinder 17, the new steam outlet of the boiler 14 is connected to the inlet of the high-pressure cylinder 15, the exhaust steam from the high-pressure cylinder 15 enters the boiler 14 for reheating, and the reheated steam outlet of the boiler 14 is connected to the inlet of the medium-pressure cylinder 16, The exhaust port of the medium pressure cylinder 16 is connected to the inlet of the low pressure cylinder 17 , and the exhaust port of the low pressure cylinder 17 is connected to the condenser 12 .

The heat recovery system includes a low-pressure heat exchanger, a deaerator 18 and a high-pressure heat exchanger that are connected in sequence through the main pipeline. The main pipeline is provided with a circulating pump for driving circulation. The inlet of the low-pressure heat exchanger is connected to the condenser 12, and the low-pressure heat exchanger A low pressure feed pump is arranged between the heat exchanger and the condenser 12, the outlet of the high pressure heat exchanger is connected to the inlet of the boiler 14; the heat exchange port of the low pressure heat exchanger is connected to the steam extraction port of the low pressure cylinder 17, and the inlet of the deaerator 18 is connected to the exhaust port of the medium pressure cylinder Steam ports, several heat exchange ports of the high pressure heat exchanger are connected to the steam extraction ports of the medium pressure cylinder 16 , and other heat exchange ports of the high pressure heat exchanger are connected to the steam extraction ports of the high pressure cylinder 15 .

The heat storage system includes a water-molten salt heat exchanger 4, a molten salt tank 2, a steam-molten salt heat exchanger 3 and a heat pump 1, and the molten salt tank 2 is a single tank; the water side inlet of the water-molten salt heat exchanger 4- 4 is connected to the outlet of the deaerator 18, the water side outlet 4-3 of the water-molten salt heat exchanger is connected to the inlet of the boiler 14 through the steam drum 13, and the molten salt side inlet 4-1 of the water-molten salt heat exchanger is connected to the top of the molten salt tank 2 , the molten salt side outlet 4-2 of the water-molten salt heat exchanger is connected to the bottom of the molten salt tank 2; the molten salt side outlet 3-3 of the steam-molten salt heat exchanger is connected to the top of the molten salt tank 2, and the steam-molten salt heat exchanger The inlet 3-4 on the molten salt side is connected to the bottom of the molten salt tank 2, the outlet 3-2 on the steam side of the steam-molten salt heat exchanger is connected to the inlet of the boiler 14 through the steam drum 13, and the inlet 3-1 on the steam side of the steam-molten salt heat exchanger is connected The outlet of heat pump 1; the primary inlet 1-1 of the heat pump 1 is connected to the fresh steam outlet of the boiler 14 through the fresh steam bypass pipeline, and the secondary inlet 1-2 of the heat pump 1 is connected to the reheat steam outlet of the boiler 14 through the reheat steam bypass pipeline.

The medium in the molten salt tank 2 is molten salt, and the upper and lower temperature distributions are formed by using the inclined temperature layer, the top and the bottom are respectively connected with two molten salt heat exchangers, and the water-molten salt heat exchanger 4 is formed when exothermic. The heat exchange circuit forms a heat exchange circuit with the steam-molten salt heat exchanger 3 during heat storage.

The heat pump 1 adopts the jet heat pump 1. It should be pointed out that the steam inlet of the primary inlet 1-1 of the jet heat pump 1 is fresh steam, and the steam inlet of the secondary inlet 1-2 is the reheated steam, which can flexibly control the quality of the steam to reach the temperature required for molten salt , in order to achieve the temperature required for heating molten salt, the opening of the first steam valve 8 and the second steam valve 7 can be adjusted under different circumstances to adjust the temperature of the steam side in the steam-molten salt heat exchanger 3. The specific adjustment process is as follows: The mature technical means in this field will not be repeated here.

The peak shaving module includes a main circuit throttle valve 19, a bypass throttle valve 11, a first molten salt pump 5, a second molten salt pump 6, a first molten salt valve 9, a second molten salt valve 10, and a first steam valve. 8 and the second steam valve 7; the main circuit throttle valve 19 is provided in the outlet water supply pipeline of the deaerator 18, the high pressure water supply pump is provided between the main circuit throttle valve 19 and the deaerator 18, and the bypass throttle valve 11 Set at the water side inlet of the water-molten salt heat exchanger 4, the first molten salt pump 5 and the first molten salt valve 9 are sequentially set at the molten salt side inlet of the water-molten salt heat exchanger 4, the second molten salt The pump 6 and the second molten salt valve 10 are sequentially arranged at the inlet of the molten salt side of the steam-molten salt heat exchanger 3, and the first steam valve 8 is arranged between the primary inlet 1-1 of the heat pump 1 and the new steam outlet of the boiler 14, The second steam valve 7 is arranged between the secondary inlet 1 - 2 of the heat pump 1 and the reheat steam outlet of the boiler 14 .

The invention also discloses a method for heat storage and peak regulation in a thermocline layer based on a high-pressure heating circuit, comprising the following steps:

A. Input the unit peak shaving target in the control center; the peak shaving target includes the peak shaving type and load adjustment target value;

B. According to the peak shaving target, the power state of the steam turbine is changed through the peak shaving module, that is, dynamic peak shaving is realized; the types of peak shaving include rapid load increase and rapid load reduction;

(a) The peak shaving process of rapidly increasing load is as follows:

a1: Open the first molten salt valve 9 and the bypass throttle valve 11, the first molten salt pump 5 works, and the second molten salt pump 6 does not work;

a2: close the first steam valve 8, the second steam valve 7 and the second molten salt valve 10;

a3: Adjust the opening of the main circuit throttle valve 19 smaller according to the load adjustment target value, the main feed water volume at the outlet of the deaerator 18 is reduced, the steam extraction volume of the high-pressure cylinder 15 and the medium-pressure cylinder 16 of the steam turbine is reduced, and the low-pressure cylinder 17 has more steam to do work Returning to the condenser 12, the work done by the steam turbine increases;

a4: A part of the feed water at the outlet of the deaerator 18 enters the water-molten salt heat exchanger 4 through the bypass throttle valve 11 for heating, and the heated water enters the steam drum 13;

a5: The hot molten salt at the top of the molten salt tank 2 is driven by the first molten salt pump 5 to release heat through the water-molten salt heat exchanger 4 and then turns into cold molten salt and returns to the bottom of the molten salt tank 2 .

When the load is rapidly increased, part of the high-pressure circuit feed water is heated by hot molten salt, which reduces the steam extraction of the high-pressure cylinder 15 and the medium-pressure cylinder 16, and increases the work of the steam turbine. The bypass feed water circuit provides heat and improves the flexibility of the unit when the load is increased.

(b) The peak shaving process for rapid load reduction is as follows:

b1: Open the first steam valve 8, the second steam valve 7, the second molten salt valve 10 and the main circuit throttle valve 19, wherein the opening degrees of the first steam valve 8 and the second steam valve 7 are adjusted to the target value according to the load make adjustments;

b2: close the first molten salt valve 9 and the bypass throttle valve 11, the first molten salt pump 5 does not work, and the second molten salt pump 6 works;

b3: The new steam and reheated steam of the boiler 14 enter the steam-molten salt heat exchanger 3 through the heat pump 1 for heat release, and the steam after releasing the heat enters the steam drum 13;

b4: The cold molten salt at the bottom of the molten salt tank 2 is heated by the steam-molten salt heat exchanger 3 under the driving of the second molten salt pump 6 and then returns to the top of the molten salt tank 2 to store heat as hot molten salt; The reheated steam heats the molten salt and stores heat, which reduces the work done by the steam turbine.

During rapid load reduction, part of the fresh steam and reheated steam heats the molten salt for heat storage, and the fresh steam and reheated steam enter the steam turbine to reduce the amount of work, which reduces the work done by the steam turbine.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or some or all of the technical features thereof are equivalently replaced, and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims (3)

1. A thermocline heat storage and peak regulation system based on a high-pressure heating circuit, including a boiler, a steam turbine, a condenser and a heat recovery system. The steam in the boiler enters the steam turbine through a steam pipeline to do work, and the boiler, steam turbine, condenser and return The heat system is connected in sequence to form a loop, and is characterized in that: it also includes a heat storage module and a peak regulation module; The steam turbine includes a high-pressure cylinder, a medium-pressure cylinder and a low-pressure cylinder. The new steam outlet of the boiler is connected to the inlet of the high-pressure cylinder, the exhaust steam of the high-pressure cylinder enters the boiler for reheating, the reheated steam outlet of the boiler is connected to the inlet of the medium-pressure cylinder, and the steam exhaust port of the medium-pressure cylinder is connected to the inlet of the medium-pressure cylinder. The inlet of the low-pressure cylinder, the exhaust port of the low-pressure cylinder is connected to the condenser; The heat recovery system includes a low-pressure heat exchanger, a deaerator and a high-pressure heat exchanger which are connected in sequence through the main pipeline. The inlet of the low-pressure heat exchanger is connected to the condenser, and the outlet of the high-pressure heat exchanger is connected to the boiler inlet. The hot port is connected to the steam extraction port of the low pressure cylinder, the inlet of the deaerator is connected to the steam exhaust port of the medium pressure cylinder, and the heat exchange port of the high pressure heat exchanger is respectively connected to the steam extraction port of the medium pressure cylinder and the steam extraction port of the high pressure cylinder; The heat storage system includes a water-molten salt heat exchanger, a molten salt tank, a steam-molten salt heat exchanger and a heat pump, and the molten salt tank is a single tank; the water-side inlet of the water-molten salt heat exchanger is connected to the deaerator outlet , the water side outlet of the water-molten salt heat exchanger is connected to the boiler inlet through the steam drum, the molten salt side inlet of the water-molten salt heat exchanger is connected to the top of the molten salt tank, and the molten salt side outlet of the water-molten salt heat exchanger is connected to the molten salt tank Bottom; the outlet of the molten salt side of the steam-molten salt heat exchanger is connected to the top of the molten salt tank, the inlet of the molten salt side of the steam-molten salt heat exchanger is connected to the bottom of the molten salt tank, and the outlet of the steam side of the steam-molten salt heat exchanger is connected through the steam drum The inlet of the boiler, the steam side inlet of the steam-molten salt heat exchanger is connected to the outlet of the heat pump; the primary inlet of the heat pump is connected to the new steam outlet of the boiler through the new steam bypass pipeline, and the secondary inlet of the heat pump is connected to the boiler reheated steam through the reheated steam bypass pipeline. Export; The peak regulation module includes a main circuit throttle valve, a bypass throttle valve, a first molten salt pump, a second molten salt pump, a first molten salt valve, a second molten salt valve, a first steam valve and a second steam valve The main circuit throttle valve is set at the water supply pipeline at the outlet of the deaerator, the bypass throttle valve is set at the water side inlet of the water-molten salt heat exchanger, and the first molten salt pump and the first molten salt valve are set in sequence in At the inlet of the molten salt side of the water-molten salt heat exchanger, the second molten salt pump and the second molten salt valve are sequentially arranged at the inlet of the molten salt side of the steam-molten salt heat exchanger, and the first steam valve is arranged at the primary heat pump Between the inlet and the outlet of the fresh steam of the boiler, the second steam valve is arranged between the secondary inlet of the heat pump and the outlet of the reheated steam of the boiler. 2 . The thermocline layer heat storage and peak regulation system based on a high-pressure heating circuit according to claim 1 , wherein the heat pump adopts a jet heat pump. 3 . 3. A peak shaving method using the high-pressure heating circuit-based thermocline heat storage and peak shaving system according to claim 1, characterized in that: comprising the following steps: A. Input the unit peak shaving target in the control center; the peak shaving target includes the peak shaving type and load adjustment target value; B. According to the peak shaving target, the power state of the steam turbine is changed through the peak shaving module, that is, dynamic peak shaving is realized; the types of peak shaving include rapid load increase and rapid load reduction; (a) The peak shaving process of rapidly increasing load is as follows: a1: Open the first molten salt valve and the bypass throttle valve, the first molten salt pump works, and the second molten salt pump does not work; a2: close the first steam valve, the second steam valve and the second molten salt valve; a3: According to the load adjustment target value, the opening of the main circuit throttle valve is reduced, the main feed water volume at the outlet of the deaerator is reduced, the steam extraction volume of the high-pressure cylinder and the medium-pressure cylinder of the steam turbine is reduced, and more steam in the low-pressure cylinder returns to the condenser. , the turbine work increases; a4: A part of the feed water at the outlet of the deaerator enters the water-molten salt heat exchanger for heating through the bypass throttle valve, and the heated water enters the steam drum; a5: The hot molten salt at the top of the molten salt tank is driven by the first molten salt pump to release heat through the water-molten salt heat exchanger and then turns into cold molten salt and returns to the bottom of the molten salt tank; (b) The peak shaving process for rapid load reduction is as follows: b1: Open the first steam valve, the second steam valve, the second molten salt valve and the main circuit throttle valve, wherein the opening degrees of the first steam valve and the second steam valve are adjusted according to the load adjustment target value; b2: close the first molten salt valve and the bypass throttle valve, the first molten salt pump does not work, and the second molten salt pump works; b3: The new steam and reheated steam of the boiler enter the steam-molten salt heat exchanger through the heat pump for heat release, and the steam after releasing the heat enters the steam drum; b4: The cold molten salt at the bottom of the molten salt tank is heated by the steam-molten salt heat exchanger under the driving of the second molten salt pump and then returns to the top of the molten salt tank to store heat as hot molten salt; The molten salt stores heat, reducing the work done by the steam turbine.

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