Supercritical or ultra-supercritical boiler rapid strengthening of working fluid side energy supply system

Abstract

The present invention relates to a supercritical or ultra-supercritical boiler rapid strengthening working medium side energy supply system in the field of energy technology, comprising: a circulating water circuit matched with the boiler, which is connected with an input pipeline and an output pipeline; a steam-water separator, which is connected to the output pipeline of the circulating water circuit; a water storage tank, which is connected to the steam-water separator; a high-temperature boiler water energy storage device with a storage chamber; an openable and closable energy storage pipeline, wherein the steam chamber of the steam-water separator and the liquid chamber of the water storage tank are connected to the input side of the high-temperature boiler water energy storage device through the energy storage pipeline; an openable and closable energy release pipeline, wherein the energy release side of the high-temperature boiler water energy storage device is connected to the input pipeline of the circulating water circuit through the energy release pipeline. The ultra-supercritical boiler rapid peak regulation and variable load response capability can be strengthened from the working medium side.

Description

Technical Field

[0001] The present invention relates to the field of energy technology, in particular to a fast-strengthening working medium-side energy supply system for a supercritical or ultra-supercritical boiler. Background Art

[0002] Under the "dual carbon" goal, the power system's power supply structure and power consumption structure will undergo significant changes. The introduction of large proportions of intermittent power sources such as wind and light will put higher requirements on the peak-shaving performance and rapid response capabilities of existing thermal power generating units.

[0003] The load-variation rate of existing traditional thermal power generation units is generally 1.0% to 1.5% of rated load per minute, with a maximum load-variation rate of up to 2.0% of rated load per minute. Future power systems based primarily on renewable energy will place even higher demands on the peak-shaving rate of thermal power generation units (5.0% to 8.0% of rated load per minute). However, traditional thermal power generation units currently cannot meet these requirements in terms of load-variation rate. The key to solving this problem is to achieve rapid energy supply from the thermal power generation unit's boiler. Therefore, how to achieve the rapid load-variation capability and response rate of thermal power generation unit boilers, and thus achieve rapid and flexible peak-shaving of thermal power generation unit boilers, is an urgent issue that needs to be addressed. Summary of the Invention

[0004] The purpose of the present invention is to provide a supercritical or ultra-supercritical boiler rapid enhanced working fluid side energy supply system, which can enhance the ultra-supercritical boiler's rapid peak regulation and variable load response capabilities from the working fluid side.

[0005] The object of the present invention is achieved as follows: a supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system, comprising:

[0006] The circulating water circuit matched with the boiler is connected with an input pipe and an output pipe;

[0007] A steam-water separator, the steam-water separator being connected to an output pipeline of a circulating water circuit;

[0008] A water storage tank connected to the steam-water separator;

[0009] A high-temperature boiler water energy storage device having a storage cavity;

[0010] An openable and closable energy storage pipeline, wherein the steam chamber of the steam-water separator and the liquid chamber of the water storage tank are connected to the input side of the high-temperature boiler water energy storage device through the energy storage pipeline;

[0011] An energy release pipeline that can be opened and closed, the release side of the high-temperature boiler water energy storage device is connected to the input pipeline of the circulating water circuit through the energy release pipeline.

[0012] Furthermore, two energy storage pipelines are provided, and the steam chamber of the steam-water separator and the liquid chamber of the water storage tank are respectively connected to the high-temperature boiler water energy storage device through the two energy storage pipelines.

[0013] Furthermore, a valve seven is provided in the energy storage pipeline connecting the steam chamber of the steam-water separator and the high-temperature boiler water energy storage device, and a valve one is provided in the energy storage pipeline connecting the liquid chamber of the water storage tank and the high-temperature boiler water energy storage device. The valve one and valve seven are in an open state during the energy storage stage, so that the steam chamber of the steam-water separator and the liquid chamber of the water storage tank are connected to the storage chamber of the high-temperature boiler water energy storage device through the energy storage pipeline.

[0014] Furthermore, the energy release pipeline is provided with a valve 2 and a mixer distributed in sequence. The valve 2 is in an open state during the period when rapid load increase and peak regulation are required. The input side of the mixer is also connected to an input pipe and is connected to the input pipe of the circulating water circuit through the input pipe. The input pipe is provided with a valve 4. When the valve 4 is in an open state, the input pipe of the circulating water circuit is connected to the input side of the mixer.

[0015] Furthermore, the energy release pipeline is also provided with a boiler water circulation pump which is in an open state during the period when rapid load increase and peak regulation are required, and the suction end of the boiler water circulation pump is connected to the output side of the mixer.

[0016] Furthermore, the energy release pipeline is also provided with a valve five which is in an open state during a period when rapid load increase and peak regulation are required, and the valve five is located on the pump outlet side of the boiler water circulation pump.

[0017] Furthermore, the input pipeline of the circulating water circuit is provided with an economizer, the pump outlet of the boiler water circulating pump is branched to connect to the input pipeline of the circulating water circuit, and the water inlet end of the economizer is connected to the pump outlet of the boiler water circulating pump.

[0018] Furthermore, the input pipeline of the circulating water circuit includes a water supply pump, a valve six, and a check valve arranged in sequence, and the access point between the input side of the mixer and the input pipeline of the circulating water circuit is between the valve six and the check valve.

[0019] Furthermore, the steam-water separator, water storage tank, high-temperature boiler water energy storage device, and mixer are distributed in order from high to low.

[0020] Furthermore, the lower part of the water storage tank is connected to a pipeline leading to the input side of the mixer, and a valve three is provided on the pipeline which is in an open state during the period when rapid load increase and peak regulation are required.

[0021] The beneficial effects of the present invention are:

[0022] It is suitable for the rapid load change conditions of supercritical boilers (or ultra-supercritical boilers) of thermal power generating units and the cold / hot start-up conditions of the units. When the unit is in load-raising condition, the high-temperature boiler water energy storage device and its system can quickly provide high-quality hot water (high-temperature, high-pressure saturated water) to the boiler to increase the thermal enthalpy of the working medium entering the boiler. At the same time, combined with the rapid supply of fuel on the furnace side, the evaporation amount of the boiler is rapidly increased, thereby improving the rapid and flexible peak-shaving capability of the unit. In addition, due to the existence of the high-temperature boiler water energy storage device, the start-up time of the boiler in cold or warm start-up can be greatly shortened, further improving the rapid and flexible peak-shaving capability of the unit boiler. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a system layout diagram of the present invention. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0025] like Figure 1 As shown, this embodiment proposes a supercritical or ultra-supercritical boiler rapid enhanced working fluid side energy supply system, including:

[0026] The circulating water circuit 6 matched with the boiler is connected to an input pipe and an output pipe, and the output pipe is provided with a superheater 5;

[0027] The steam-water separator 13 is connected to the output pipe of the circulating water circuit 6;

[0028] A water storage tank 14 is connected to the steam-water separator 13;

[0029] A high-temperature boiler water energy storage device 15 having a storage cavity, the main body of which is a high-temperature resistant and pressure-bearing structure with a heat-insulating function;

[0030] The steam chamber of the steam-water separator 13 and the liquid chamber of the water storage tank 14 are connected to the input side of the high-temperature boiler water energy storage device 15 through the energy storage pipeline.

[0031] The energy release pipeline can be opened and closed, and the energy release side of the high-temperature boiler water energy storage device 15 is connected to the input pipeline of the circulating water circuit 6 through the energy release pipeline.

[0032] Among them, there are two energy storage pipelines, and the steam chamber of the steam-water separator 13 and the liquid chamber of the water storage tank 14 are respectively connected to the high-temperature boiler water energy storage device 15 through two energy storage pipelines; a valve 7 12 is provided in the energy storage pipeline connecting the steam chamber of the steam-water separator 13 and the high-temperature boiler water energy storage device 15, and a valve 17 is provided in the energy storage pipeline connecting the liquid chamber of the water storage tank 14 and the high-temperature boiler water energy storage device 15. The opening / closing of valve 17 is used to realize energy storage in the high-temperature boiler water energy storage device 15 and isolation between the new energy supply system and the original boiler steam-water system. Valve 17 and valve 12 are in the open state during the energy storage stage, so that the steam chamber of the steam-water separator 13 and the liquid chamber of the water storage tank 14 are connected to the storage chamber of the high-temperature boiler water energy storage device 15 through the energy storage pipeline. The high-temperature boiler water energy storage device 15 passes the steam generated in the energy storage or release process into the steam-water separator 13 through the pipeline and valve 7 12 for separation, and balances the pressure between the high-temperature boiler water energy storage device 15 and the steam-water separator 13 and the water storage tank 14 to maintain pressure balance.

[0033] The above-mentioned energy release pipeline is provided with valve 2 8 and mixer 16 distributed in sequence. Valve 2 8 is in an open state during the period when rapid load increase and peak regulation are required. The input side of the mixer 16 is also connected to an input pipe and is connected to the input pipe of the circulating water circuit 6 through the input pipe. Valve 4 10 is provided in the input pipe. When valve 4 10 is in an open state, the input pipe of the circulating water circuit 6 is connected to the input side of the mixer 16.

[0034] The energy release pipeline is also provided with a boiler water circulation pump 17 which is turned on when the unit boiler needs to be started, during low-load operation and during rapid load increase and peak regulation. The suction end of the boiler water circulation pump 17 is connected to the output side of the mixer 16.

[0035] The energy release pipeline is also provided with a valve 5 11 which is in an open state during the period when rapid load increase and peak regulation are required. The valve 5 11 is located on the pump outlet side of the boiler water circulation pump 17. By adjusting the opening of the valve 5 11, the proportion of high-temperature boiler water entering the economizer 4 is adjusted, thereby adjusting the inlet water temperature entering the boiler water-cooled wall system to ensure that the boiler wall temperature of the unit does not exceed the temperature and operates safely.

[0036] The inlet of the circulating water circuit 6 is equipped with an economizer 4. The outlet of the boiler water circulating pump 17 is branched off to connect to the inlet of the circulating water circuit 6. The water inlet of the economizer 4 is connected to the outlet of the boiler water circulating pump 17. Valve 5 11 and economizer 4 are connected in parallel to the outlet of the boiler water circulating pump 17.

[0037] The input pipeline of the above-mentioned circulating water circuit 6 includes a water supply pump 1, a valve 6 2, and a check valve 3 arranged in sequence. The access point between the input side of the mixer 16 and the input pipeline of the circulating water circuit 6 is between the valve 6 2 and the check valve 3.

[0038] The steam-water separator 13, water storage tank 14, high-temperature boiler water energy storage device 15, and mixer 16 are distributed in order from high to low. The lower part of the water storage tank 14 is connected to a pipe leading to the input side of the mixer 16, and a valve 9 is provided on the pipe to be in an open state during startup, low load, and peak load regulation when rapid load increase is required.

[0039] The bottom outlet of the high-temperature boiler water energy storage device 15 is converged into the mixer 16 through the pipeline and valve two 8 with the low-temperature water feed branch of the water feed pump 1 and the high-temperature water branch of the water storage tank 14. The inlet temperature of the boiler water circulation pump 17 is adjusted by adjusting the opening of valve two 8, valve three 9 and valve four 10 (the inlet water temperature of the boiler water circulation pump 17 is controlled below 400°C to prevent the occurrence of local vaporization and ensure the safe and reliable operation of the boiler water circulation pump 17); by adjusting the opening of valve five 11, the flow distribution of the high-temperature boiler water at the outlet of the boiler water circulation pump 17 into the economizer 4 and the boiler water-cooled wall inlet header is realized, so that the outlet temperature of the economizer 4 and the working medium temperature of the boiler furnace water-cooled wall inlet can be adjusted within a certain range, ensuring that the unit boiler has the ability to quickly increase the load rate while ensuring the wall temperature safety of the furnace water-cooled wall and the high-temperature heating surface. By controlling valve one 7, valve two 8, valve three 9, valve four 10, valve five 11 and controlling the opening / starting of the boiler water circulating water pump 17, the energy release of the high-temperature boiler water energy storage device 15, the rapid load change process, and the connection and isolation between the new energy supply system and the original boiler circulating water system are realized.

[0040] During normal load operation of the unit, valve one 7, valve two 8, valve three 9, valve four 10, valve five 11, valve seven 12 are closed and the boiler water circulation pump 17 is started. At this time, the working fluid side energy storage-energy supply system is isolated from the original boiler working fluid circulation system (circulating water circuit 6), and the feed water is pumped in by the feed water pump 1, and the working fluid is heated, evaporated and superheated through the heating surfaces such as the economizer 4, furnace water-cooled wall, and superheater 5.

[0041] During the unit's high-load operation and energy storage period, in addition to the boiler's normal supply of high-quality steam, the fuel-water ratio is adjusted to ensure that the steam entering the startup steam-water separator 13 is undersaturated steam at a certain pressure and temperature. Under the action of the startup steam-water separator 13, high-temperature boiler water with a high enthalpy accumulates in the water storage tank 14. When the liquid level reaches a certain level, energy is stored in the high-temperature boiler water energy storage device 15 by opening valve 17 and valve 7 12 at the top of the high-temperature boiler water energy storage device 15 (at this time, valves 2 8, 3 9, and 5 11 are closed, valve 4 10 is open, and the startup boiler water circulation pump 17 is in a standby state). In addition, the opening of valve 17 can be used to control the water level in the water storage tank 14 and the temperature change rate of the high-temperature boiler water energy storage device 15 (below 400°C), ensuring safe and stable operation of the boiler. When the energy storage process is completed, valves 17, 4 10, 7 12, and the startup boiler water circulation pump 17 are closed to isolate the high-temperature boiler water energy storage system from the original boiler water circulation system.

[0042] During the period when the unit needs to quickly increase the load and peak, the working fluid side energy storage-energy supply system needs to release energy quickly, open valve two 8, valve three 9, valve four 10, valve five 11, valve seven 12 and start the boiler water circulation pump 17 (valve one 7 is in the closed state), and the high-temperature boiler water and low-temperature feed water are fully mixed in the mixer 16 and then pumped into the circulating water path 6 of the boiler furnace through the boiler water circulation pump 17 to quickly increase the thermal enthalpy of the working fluid entering the furnace, and by coordinating with the increase in the amount of fuel entering the furnace, quickly increase the boiler evaporation capacity and variable load response rate; in addition, in the high-temperature boiler water energy storage device 1 During the energy release process, the opening of valve 4 10 is controlled to keep the water temperature at the inlet of the boiler water circulation pump under control, and the inlet water temperature of the boiler water circulation pump 17 is kept below 400°C to prevent the occurrence of local vaporization and ensure the safety of the water circulation system. After the energy release process of the high-temperature boiler water energy storage device 15 is completed, valve 2 8, valve 3 9, valve 4 10, valve 5 11, valve 7 12 are closed and the boiler water circulation pump 17 is started to isolate the high-temperature boiler water energy storage system from the original boiler water circulation system, and wait for the unit boiler to carry out the next energy storage process under non-peak load conditions.

[0043] In addition, since the high-temperature boiler water energy storage device 15 stores high-quality hot water, the energy storage-release process of the high-temperature boiler water energy storage device 15 needs to be performed regularly according to the load operation of the unit to ensure that the high-temperature boiler water energy storage device 15 is always in an available state and at a higher temperature level, so that the unit boiler can have the ability to respond to rapid load changes at any time.

[0044] Since the new energy storage-supply system on the working fluid side directly stores high-temperature boiler water under high-load or excess load conditions, there is no heat exchange process between the high-temperature working fluid and other energy storage media during the energy storage and release process. Therefore, it has the characteristics of high thermal efficiency, fast response speed, simple / reliable system, low investment and operating costs, and good engineering implementation feasibility.

[0045] The above are preferred implementation cases of the present invention. Ordinary technicians in this field can also make various changes or improvements on this basis. Without departing from the overall concept of the present invention, these changes or improvements should fall within the scope of protection required by the present invention.

Claims

1. A supercritical or ultra-supercritical boiler rapid enhanced working fluid side energy supply system, characterized in that: include: A circulating water circuit (6) matched with the boiler, which is connected with an input pipeline and an output pipeline; A steam-water separator (13), wherein the steam-water separator (13) is connected to an output pipeline of the circulating water circuit (6); A water storage tank (14), wherein the water storage tank (14) is connected to the steam-water separator (13); A high-temperature furnace water energy storage device (15) having a storage chamber; An energy storage pipeline that can be opened and closed, wherein the steam chamber of the steam-water separator (13) and the liquid chamber of the water storage tank (14) are connected to the input side of the high-temperature boiler water energy storage device (15) through the energy storage pipeline; An energy release pipeline that can be opened and closed, wherein the energy release side of the high-temperature furnace water energy storage device (15) is connected to the input pipeline of the circulating water circuit (6) through the energy release pipeline; The energy storage pipeline is provided with two, and the steam chamber of the steam-water separator (13) and the liquid chamber of the water storage tank (14) are respectively connected to the high-temperature boiler water energy storage device (15) through the two energy storage pipelines. The energy release pipeline is provided with valve two (8) and a mixer (16) which are distributed in sequence. The valve two (8) is in an open state during the period when rapid load increase and peak regulation are required. The input side of the mixer (16) is also connected to an input pipeline and is connected to the input pipeline of the circulating water circuit (6) through the input pipeline. The input pipeline is provided with valve four (10). When the valve four (10) is in an open state, the input pipeline of the circulating water circuit (6) is connected to the input side of the mixer (16).

2. A supercritical or ultra-supercritical boiler rapid enhanced working fluid side energy supply system according to claim 1, characterized in that: A valve seven (12) is provided in the energy storage pipeline connecting the steam chamber of the steam-water separator (13) and the high-temperature boiler water energy storage device (15), and a valve one (7) is provided in the energy storage pipeline connecting the liquid chamber of the water storage tank (14) and the high-temperature boiler water energy storage device (15). The valve one (7) and the valve seven (12) are in an open state during the energy storage stage, so that the steam chamber of the steam-water separator (13) and the liquid chamber of the water storage tank (14) are connected to the storage chamber of the high-temperature boiler water energy storage device (15) through the energy storage pipeline.

3. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 1, characterized in that: The energy release pipeline is also provided with a boiler water circulation pump (17) which is turned on when the boiler needs to be started, during low-load operation and during rapid load increase and peak regulation. The suction end of the boiler water circulation pump (17) is connected to the output side of the mixer (16).

4. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 3, characterized in that: The energy release pipeline is also provided with a valve five (11) which is in an open and adjustable state during the period when rapid load increase and peak regulation are required, and the valve five (11) is located on the pump outlet side of the boiler water circulation pump (17).

5. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 3, characterized in that: The input pipeline of the circulating water circuit (6) is provided with an economizer (4), the pump outlet end of the boiler water circulating water pump (17) is provided with a branch to connect to the input pipeline of the circulating water circuit (6), and the water inlet end of the economizer (4) is connected to the pump outlet end of the boiler water circulating water pump (17).

6. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 3, characterized in that: The input pipeline of the circulating water circuit (6) comprises a water supply pump (1), a valve six (2), and a check valve (3) which are arranged in sequence, and the connection point between the input side of the mixer (16) and the input pipeline of the circulating water circuit (6) is located between the valve six (2) and the check valve (3).

7. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 1, characterized in that: The steam-water separator (13), the water storage tank (14), the high-temperature boiler water energy storage device (15), and the mixer (16) are arranged in order from high to low.

8. A supercritical or ultra-supercritical boiler rapid enhanced working medium side energy supply system according to claim 7, characterized in that: The lower part of the water storage tank (14) is connected to a pipeline leading to the input side of the mixer (16), and a valve three (9) is provided on the pipeline which needs to be in an open state during boiler startup, low-load operation and rapid load increase peak regulation.

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