CN117379727A

CN117379727A - A method for cooling and extinguishing liquid nitrogen and fine water mist in an electrochemical energy storage power station

Info

Publication number: CN117379727A
Application number: CN202311178883.0A
Authority: CN
Inventors: 王志; 宋宇辰; 余先宇; 王少嘉; 史波波; 惠铭轩; 安伟光; 李志华
Original assignee: China University of Mining and Technology Beijing CUMTB
Current assignee: China University of Mining and Technology Beijing CUMTB
Priority date: 2023-09-13
Filing date: 2023-09-13
Publication date: 2024-01-12
Anticipated expiration: 2043-09-13
Also published as: CN117379727B

Abstract

The present disclosure relates to the field of fire protection, and in particular to a liquid nitrogen and water mist linked cooling and fire extinguishing method for an electrochemical energy storage power station. The fire extinguishing system used includes a nitrogen supply device, a nitrogen recovery device, a water supply device and a gas-liquid two-phase flow nozzle; the nitrogen supply device includes a liquid nitrogen pump, a liquid nitrogen storage tank, a vaporization device, a gas mixing chamber and a pressurizing device; a nitrogen recovery device It includes a pressure sensor, a nitrogen valve, an air induction device, a rotary separation device, a nitrogen purification device and a cooler; the water supply device includes a nitrogen branch pipe, a water tank, a water outlet pipe and a water valve; the nitrogen branch pipe is connected to the top of the water tank; a nozzle is formed with Water channel, gas phase channel branch pipe and gas phase channel; the cross-sectional area of the water channel first remains unchanged in the direction of water flow, then shrinks, and finally expands; the gas phase channel branch pipe is provided with an air outlet; the water channel is provided adjacent to the gas phase channel branch pipe There are spoiler bulges. The system is environmentally friendly, has high fire extinguishing efficiency and has strong ability to resist re-ignition.

Description

Liquid nitrogen and water mist linkage cooling fire extinguishing method for electrochemical energy storage power station

Technical Field

The disclosure relates to the field of fire protection, in particular to a liquid nitrogen and water mist linkage cooling fire extinguishing method for an electrochemical energy storage power station.

Background

The electrochemical energy storage power station is a power supply facility for storing surplus electric energy of a power grid in a valley period by using a large battery pack and sending the surplus electric energy back to the power grid in a peak period to relieve the power shortage. Electrochemical energy storage power stations typically include an energy storage compartment. The battery pack (e.g., lithium battery pack) is stored on a support frame of a multi-layered structure. During the storage process of the battery pack, a great deal of heat release of the battery pack is caused by mechanical abuse, electric abuse or thermal abuse, if the released heat cannot be timely released, the released heat can accumulate in the energy storage cabin, and even fire explosion is caused.

Traditional extinguishing devices generally produce toxic and harmful substances in the process of extinguishing fire, or have lower extinguishing efficiency for fires in electrochemical energy storage power stations.

Disclosure of Invention

Technical problems:

the fire extinguishing system and the method suitable for the electrochemical energy storage power station are high in fire extinguishing efficiency, strong in reburning resistance, environment-friendly and low in cost.

The technical scheme is as follows:

in one aspect, a liquid nitrogen and water mist linkage cooling fire extinguishing system of an electrochemical energy storage power station is provided. It comprises the following steps: the device comprises a nitrogen supply device, a nitrogen recovery device, a water supply device and at least one gas-liquid two-phase flow nozzle; the nitrogen supply device comprises a liquid nitrogen pump, a liquid nitrogen storage tank, a vaporization device, a gas mixing chamber and a pressurizing device which are sequentially communicated; the gas mixing chamber is communicated with the pressurizing device through a first pipeline; the nitrogen recovery device comprises a pressure sensor, a nitrogen valve, an induced draft device, a rotary separation device, a nitrogen purification device and a cooler which are sequentially communicated; the air outlet of the cooler is communicated with the air inlet of the gas mixing chamber; the water supply device comprises a nitrogen branch pipe, a water tank, a water outlet pipe and a water valve; the air inlet of the nitrogen branch pipe is communicated with the first pipeline, and the air outlet of the nitrogen branch pipe is communicated with the top of the water tank; the water outlet pipe is communicated with the water tank at a position close to the bottom; the water valve is arranged on the water outlet pipe, so that water in the water tank is conveyed outwards along the water outlet pipe by utilizing the air pressure provided by the nitrogen branch pipe; the gas-liquid two-phase flow nozzle comprises a nozzle body and a nozzle head; a water channel, a gas channel branch pipe and a plurality of gas channels are formed in the nozzle body; the inlet end of the water channel is communicated with the water outlet pipe; the gas phase passage branch pipes and the inlet ends of the gas phase passages are respectively communicated with the supercharging device; the water channel and the outlet ends of the plurality of gas phase channels are respectively communicated with the nozzle head; a plurality of the gas phase passages are uniformly arranged around the water passage; the sectional area of the water channel is unchanged in the water flow direction, and then is reduced and finally is expanded; the gas phase channel branch pipe extends along the central axis of the water channel, the end part of the gas phase channel branch pipe opposite to the inlet end of the gas phase channel branch pipe is sealed, and a plurality of air outlet holes are formed in the gas phase channel branch pipe along different directions; the air outlet holes are all positioned at the upstream of the necking part of the water channel; and a plurality of turbulence convex parts are arranged on the inner wall of the water channel and close to the gas phase channel branch pipes.

In some embodiments, the number of gas phase channels is four; four of the gas-phase passages are uniformly arranged in the circumferential direction of the water passage.

In some embodiments, the tangential direction of the outlet end of the gas phase passage is at an angle of 60 ° to the direction of the central axis of the water passage.

In some embodiments, the outlet aperture is square in shape.

In some embodiments, the electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system further comprises a humidity sensor, a controller and a ventilation device; the electrochemical energy storage power station comprises an energy storage cabin; the humidity sensor is configured to monitor humidity within the energy storage compartment; the ventilation device is configured to openably and closably exchange gas between the energy storage compartment and an outdoor environment; the controller is respectively and electrically connected with the humidity sensor, the water valve and the ventilation device; the controller is configured to: when the data of the humidity sensor is determined to be out of a preset range, controlling the water valve to be closed, and simultaneously keeping the gas phase channel branch pipes and the gas phase channels open; the water tank is filled with purified water.

In some embodiments, the gas-liquid two-phase flow nozzle further has a gas phase channel manifold formed therein; the inlet end of the gas phase channel main pipe is communicated with the supercharging device; the outlet end of the gas phase channel main pipe is respectively communicated with the gas phase channel branch pipes and a plurality of gas phase channels; the main body parts of the gas phase channels extend in a straight line and are positioned outside the water channels.

In some embodiments, at least one air channel is also formed in the nozzle body at a location proximate the nozzle head; the air passage is configured to communicate outside air with the gas-phase passage; and the air channel is provided with a one-way air inlet valve.

In some embodiments, a recycle nitrogen inlet valve and a first thermometer are also mounted on the line between the cooler and the gas mixing chamber.

In some embodiments, the tank contains a complex aqueous solution containing 10% potassium chloride and 10% ammonium dihydrogen phosphate.

In some embodiments, the nozzle opening of the nozzle head is hexagonal in shape.

In some embodiments, the vaporization apparatus is an air temperature vaporization apparatus.

In some embodiments, the number of gas-liquid two-phase flow nozzles is a plurality; a multi-layer supporting frame is arranged in the energy storage cabin; a plurality of battery packs are placed on the multi-layer support frame in a layered manner; the gas-liquid two-phase flow nozzles are respectively arranged facing the top surface and the side surface of the battery pack, and a preset distance is kept between the gas-liquid two-phase flow nozzles and the battery pack.

In some embodiments, the inlet end of the vaporizing device is provided with a liquid nitrogen inlet valve, and the outlet end of the vaporizing device is provided with a nitrogen outlet valve, a nitrogen flow meter and a second thermometer.

In some embodiments, the nitrogen manifold has a first pressure gauge mounted thereon; the water outlet pipe is also provided with a water flowmeter; a second pressure gauge is also arranged on a pipeline between the supercharging device and the gas-liquid two-phase flow nozzle; and a nitrogen flow control valve is arranged on the gas phase channel.

On the other hand, the liquid nitrogen and water mist linkage cooling fire extinguishing method of the electrochemical energy storage power station is also provided. The method is based on the liquid nitrogen and water mist linkage cooling fire extinguishing system of the electrochemical energy storage power station, and comprises the following steps: and when the nitrogen recovery device is determined to be started, controlling the recovered nitrogen inlet valve according to the data of the first thermometer and the second thermometer so as to adjust the flow of the recovered nitrogen into the gas mixing chamber.

In some embodiments, the method comprises the steps of:

controlling the nitrogen outlet valve according to the measured data of the nitrogen flowmeter and the second thermometer to regulate the flow of nitrogen flowing out of the vaporizing device so as to control the temperature of the nitrogen flowing out of the vaporizing device, wherein the temperature of the nitrogen flowing out of the vaporizing device is more than 0 ℃;

and when the data of the pressure sensor is determined to be within a preset pressure range, opening the nitrogen valve to start the nitrogen recovery device.

In some embodiments, the method further comprises the steps of:

according to the measured data of the first pressure gauge and the water flow meter, controlling the flow of nitrogen of the nitrogen branch pipe and the water valve to regulate the water flow in the water channel;

the pressure value of the second pressure gauge reaches 0.5MPa through the pressurizing device, and the nitrogen flow control valve is controlled to adjust the nitrogen flow in the gas phase channel;

the water flow in the water channel and the nitrogen flow in the gas phase channel are regulated to regulate the mixing proportion of nitrogen and water at the nozzle head so as to regulate the atomization effect of the water mist sprayed out by the nozzle head.

The beneficial effects are that:

1. the invention creatively couples the liquid nitrogen cooling fire extinguishing and the water mist cooling fire extinguishing together through the specially designed liquid nitrogen and water mist linkage cooling fire extinguishing system, and the system has the advantages of simple structure, environmental protection, high fire extinguishing efficiency, strong reburning resistance, no damage to equipment in the electrochemical energy storage power station and low fire extinguishing cost;

2. compared with the prior art of directly utilizing nitrogen to extinguish fire, the invention utilizes the liquid nitrogen storage tank to supply low-temperature nitrogen in combination with the vaporizing device, can adjust the temperature of the nitrogen according to the requirement, and has better cooling and fire extinguishing effects;

3. according to the invention, the nitrogen branch pipe is arranged to enter the top of the water tank, the nitrogen pressure is reasonably utilized to convey water in the water tank to the gas-liquid two-phase flow nozzle, a high-energy consumption power device such as a water pump is not needed, the equipment structure is simple, the energy consumption and the equipment cost are low, and the high-pressure water mist effect of the gas-liquid two-phase flow nozzle can be ensured;

4. the invention also introduces a nitrogen recovery device which controls the on-off of the nitrogen valve according to the data of the pressure sensor, thereby controlling the on-off of the nitrogen recovery device. When the nitrogen recovery device is started, negative pressure is generated in the space to be extinguished of the electrochemical energy storage power station through the induced draft device, gas generated by fire and extinguishment is sucked into the nitrogen recovery pipeline, and the internal air pressure and the combustible gas content of the space to be extinguished are reduced; adopting a rotary separation device to separate nitrogen from the mixed gas; purifying the separated nitrogen by adopting a nitrogen purifying device; cooling the purified nitrogen by adopting a cooler to obtain recovered nitrogen; finally, the recovered nitrogen and the low-temperature nitrogen flowing out of the vaporizing device are mixed in a gas mixing chamber. The nitrogen recovery device is used for recycling nitrogen, so that the nitrogen utilization rate can be improved, the cost is reduced, the fire extinguishing efficiency is improved, and the protection to the environment is enhanced.

5. The invention also optimizes the structure of the gas-liquid two-phase flow nozzle, realizes the high-efficiency linkage of low-temperature nitrogen and the fine water mist, effectively improves the atomization degree and the spraying strength of the fine water mist, has low failure rate, can efficiently absorb the heat generated by fire and plays a role in rapid cooling; meanwhile, combustion-supporting substances such as oxygen and the like are isolated from contacting with combustible substances, so that the occurrence and the spread of fire are inhibited; has good and rapid fire extinguishing capability and afterburning resistance:

the low-temperature nitrogen is adopted for auxiliary atomization, the gas-liquid two-phase flow nozzle can fully mix the low-temperature nitrogen with water, so that the water and the nitrogen form a uniform nitrogen and water mist two-phase mixture under mutual impact, and the water mist and the nitrogen are sprayed out from the same nozzle head to cool and extinguish the fire, thereby improving the atomization level of the water mist;

partial nitrogen is led into the water channel by utilizing a plurality of air outlet holes on the gas phase channel branch pipe, so that liquid is broken into large liquid drops, liquid wires and liquid films, and then is broken into small liquid drops, thereby being beneficial to improving the atomization effect at the nozzle head;

the turbulence convex parts are arranged in the water channel, so that on one hand, the turbulence degree of water in the water channel is increased, the water is broken into small liquid drops, and the atomization degree is improved; on the other hand, as the turbulence convex part is close to the gas phase channel branch pipe, partial water flow can be guided to the air outlet hole, so that the interaction between the water flow and nitrogen flowing out of the gas phase channel branch pipe is facilitated, the water mist particle size of the fine water mist is reduced, and the atomization effect is improved;

through the structural design that the sectional area of the water channel is unchanged in the water flow direction, is reduced and finally is expanded, the water flow speed can be improved, negative pressure is formed at the nozzle head, and therefore the atomization degree of the fine water mist is improved.

Drawings

In order to more clearly illustrate the technical solutions of the present disclosure, the drawings that are required to be used in some embodiments of the present disclosure will be briefly described below, however, the drawings in the following description are only drawings of some embodiments of the present disclosure, and other drawings may be obtained according to these drawings for those of ordinary skill in the art. Furthermore, the drawings in the following description may be regarded as schematic representations, not as limiting the actual dimensions of the products according to the embodiments of the present disclosure.

FIG. 1 is a schematic diagram of a liquid nitrogen and water mist linked cooling fire suppression system for an electrochemical energy storage power station in accordance with some embodiments;

FIG. 2 is a schematic diagram of the layout cross-sectional structure of the gas-liquid two-phase flow nozzle of FIG. 1;

FIG. 3 is a schematic diagram of the layout of an electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system in an energy storage compartment according to some embodiments;

fig. 4 illustrates the relative positions of a gas-liquid two-phase flow nozzle and a battery pack of some embodiments.

Detailed Description

The following description of the embodiments of the present disclosure will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by one of ordinary skill in the art based on the embodiments provided by the present disclosure are within the scope of the present disclosure.

Throughout the specification and claims, the term "comprising" is to be interpreted as an open, inclusive meaning, i.e. "comprising, but not limited to, unless the context requires otherwise. In the description of the present specification, the terms "one embodiment," "some embodiments," "example embodiments," "examples," "particular examples," or "some examples," etc., are intended to indicate that a particular feature, structure, material, or characteristic associated with the embodiment or example is included in at least one embodiment or example of the present disclosure. The schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The terms "first" and "second" are used below for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the embodiments of the present disclosure, unless otherwise indicated, the meaning of "a plurality" is two or more.

In describing some embodiments, expressions of "coupled" and "connected" and their derivatives may be used. The term "coupled" is to be interpreted broadly, as referring to, for example, a fixed connection, a removable connection, or a combination thereof; can be directly connected or indirectly connected through an intermediate medium. The term "coupled" means that two or more elements are in direct physical or electrical contact. The term "coupled" or "communicatively coupled" may also mean that two or more elements are not in direct contact with each other, but yet still co-operate or interact with each other. The embodiments disclosed herein are not necessarily limited to the disclosure herein.

At least one of "A, B and C" has the same meaning as at least one of "A, B or C," both include the following combinations of A, B and C: a alone, B alone, C alone, a combination of a and B, a combination of a and C, a combination of B and C, and a combination of A, B and C.

"A and/or B" includes the following three combinations: only a, only B, and combinations of a and B.

As used herein, the term "if" is optionally interpreted to mean "when … …" or "at … …" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if determined … …" or "if detected [ stated condition or event ]" is optionally interpreted to mean "upon determining … …" or "in response to determining … …" or "upon detecting [ stated condition or event ]" or "in response to detecting [ stated condition or event ]" depending on the context.

The use of "adapted" or "configured to" herein is meant to be an open and inclusive language that does not exclude devices adapted or configured to perform additional tasks or steps.

In addition, the use of "based on" is intended to be open and inclusive in that a process, step, calculation, or other action "based on" one or more of the stated conditions or values may be based on additional conditions or beyond the stated values in practice.

As used herein, "about," "approximately" or "approximately" includes the stated values as well as average values within an acceptable deviation range of the particular values as determined by one of ordinary skill in the art in view of the measurement in question and the errors associated with the measurement of the particular quantity (i.e., limitations of the measurement system).

As used herein, "parallel", "perpendicular", "equal" includes the stated case as well as the case that approximates the stated case, the range of which is within an acceptable deviation range as determined by one of ordinary skill in the art taking into account the measurement in question and the errors associated with the measurement of the particular quantity (i.e., limitations of the measurement system). For example, "parallel" includes absolute parallel and approximately parallel, where the acceptable deviation range for approximately parallel may be, for example, a deviation within 5 °; "vertical" includes absolute vertical and near vertical, where the acceptable deviation range for near vertical may also be deviations within 5 °, for example. "equal" includes absolute equal and approximately equal, where the difference between the two, which may be equal, for example, is less than or equal to 5% of either of them within an acceptable deviation of approximately equal.

In some embodiments, an electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system 1000 is provided. As shown in fig. 1 to 4, it includes: a nitrogen supply 100, a nitrogen recovery 200, a water supply 300, and at least one gas-liquid two-phase flow nozzle 400.

The nitrogen supply device 100 includes a liquid nitrogen pump 12, a liquid nitrogen storage tank 11, a vaporizing device 13 (e.g., an air temperature vaporizer), a gas mixing chamber 14, and a pressurizing device 15, which are sequentially communicated. The gas mixing chamber 14 is communicated with the pressurizing device 15 through a first pipeline. Specifically, the liquid nitrogen pump 12 communicates with the liquid nitrogen tank 11 through a pipe, whereby the liquid nitrogen pump 12 can pressurize the liquid nitrogen tank 11, thereby outputting the liquid nitrogen in the liquid nitrogen tank 11 to the vaporizing device 13. When cooling is needed to extinguish a fire, the working principle of the nitrogen supply device is as follows: the liquid nitrogen tank 11 is pressurized by the liquid nitrogen pump 12 to output the liquid nitrogen in the liquid nitrogen tank 11 to the vaporizing device 13. The liquid nitrogen is vaporized to nitrogen gas of 0 degrees or more by a vaporizing device 13 (for example, an air temperature vaporizer). The nitrogen gas is pressurized to 0.5MPa by the pressurizing means 15, and is sent to the gas-liquid two-phase flow nozzle 400 at a low pressure.

The nitrogen recovery device 200 comprises a pressure sensor 21, a nitrogen valve 22, an induced draft device 23, a rotary separation device 24, a nitrogen purification device 25 and a cooler 26 which are sequentially communicated through a nitrogen recovery pipeline 211; the outlet of the cooler 26 communicates with the inlet of the gas mixing chamber 14. The switch of the nitrogen valve 22 is controlled according to the data of the pressure sensor 21. Specifically, the nitrogen valve 22 is installed on the space to be extinguished (such as the energy storage cabin 2000) of the electrochemical energy storage power station, and when the pressure in the space to be extinguished (such as the energy storage cabin 2000) of the electrochemical energy storage power station is determined to be within the preset pressure range, that is, when the pressure data of the pressure sensor 21 is within the preset pressure range, the nitrogen valve 22 is opened to start to recover nitrogen. When the nitrogen recovery device 200 needs to be started, the nitrogen valve 22 is started, negative pressure is generated in a space (such as the energy storage cabin 2000) to be extinguished of the electrochemical energy storage power station through the induced draft device 23, gas generated by fire and extinguishment is sucked into the nitrogen recovery pipeline 211, and the internal air pressure and the combustible gas content of the space to be extinguished are reduced; separating nitrogen from the mixed gas by using a rotary separation device 24; purifying the separated nitrogen gas by a nitrogen gas purifying device 25; the purified nitrogen is cooled by a cooler 26 to obtain recovered nitrogen; finally, the recovered nitrogen is mixed with the low-temperature nitrogen flowing out of the vaporizing device 13 in the gas mixing chamber 14. Thus, the nitrogen gas supply apparatus 100 and the nitrogen gas recovery apparatus 200 in this embodiment are communicated to form a loop, and the mixing of the nitrogen gas supplied from the nitrogen gas supply apparatus 100 and the recovered nitrogen gas supplied from the nitrogen gas recovery apparatus 200 is achieved. The nitrogen recovery device 200 can recycle nitrogen, so that the nitrogen utilization rate can be improved, the cost can be reduced, the fire extinguishing efficiency can be improved, and the protection to the environment can be enhanced.

The water supply device 300 includes a nitrogen manifold 31, a water tank 32, a water outlet pipe 33, and a water valve 34; the air inlet of the nitrogen branch pipe 31 is communicated with a first pipeline, and the air outlet of the nitrogen branch pipe 31 is communicated with the top of the water tank 32; the water outlet pipe 33 is communicated with the water tank 32 at a position close to the bottom; a water valve 34 is mounted on the water outlet pipe 33. The water valve 34 is configured to adjust the water flow rate of the water outlet pipe 33. Thus, part of the nitrogen in the first line can enter the top of the water tank 32 through the nitrogen branch pipe 31, thereby delivering the water in the water tank 32 to the gas-liquid two-phase flow nozzle 400 using the nitrogen pressure. The water supply device 300 of this embodiment does not need a high-energy consumption power device such as a water pump, has a simple device structure and low energy consumption and device cost, can realize the transportation of water from the water tank 32 to the gas-liquid two-phase flow nozzle 400, and can ensure the high-pressure water mist effect of the gas-liquid two-phase flow nozzle 400.

The gas-liquid two-phase flow nozzle 400 includes a nozzle body 41 and a nozzle head 42; the nozzle body 41 has a water passage 411, a gas-phase passage branch pipe 412, and a plurality of gas-phase passages 413 formed therein; the inlet end of the water channel 411 is communicated with the water outlet pipe; the gas phase passage branch pipe 413 and inlet ends of the plurality of gas phase passages 413 are respectively communicated with the pressurizing device 15; the outlet ends of the water passage 411 and the plurality of gas-phase passages 413 are respectively communicated with the nozzle head 42; a plurality of gas phase passages 413 are uniformly arranged around the water passage 411; the cross-sectional area of the water channel 411 is a trend of constant in the water flow direction, and then is reduced and finally is enlarged; the gas phase channel branch pipe 412 extends along the central axis of the water channel 411, the end of the gas phase channel branch pipe 412 opposite to the inlet end is closed, and a plurality of gas outlet holes 4121 are formed on the gas phase channel branch pipe 412 along different directions; the plurality of air outlet holes 4121 are all positioned upstream of the necking 4111 of the water channel 411; a plurality of turbulence protrusions 4112 are also provided on the inner wall of the water passage 411 at positions adjacent to the gas-phase passage branch 412. The gas-liquid two-phase flow nozzle 400 is configured to link the nitrogen supply apparatus 100 with the water supply apparatus 300. The nitrogen supply 100 is used to supply liquid nitrogen. The liquid nitrogen has the characteristics of low temperature and incombustibility, can be used for rapidly cooling and isolating oxygen when being used for extinguishing fire, and can not damage equipment in an electrochemical energy storage power station, thereby being environment-friendly. The water supply device 300 can generate fine water mist in combination with the gas-liquid two-phase flow nozzle 400. The water mist particle size of the fine water mist is small, the contact area between the fine water mist and air can be increased, the heat absorption capacity of fire extinguishment is improved, and the temperature generated by fire explosion can be effectively reduced, so that the fire extinguishment is facilitated. The nitrogen gas supply apparatus 100 and the water supply apparatus 300 of the present embodiment have simple structures. By optimally designing the gas-liquid two-phase flow nozzle 400: the low-temperature nitrogen is adopted for auxiliary atomization, the gas-liquid two-phase flow nozzle 400 can fully mix the low-temperature nitrogen with water, so that the water and the nitrogen form a uniform nitrogen and water mist two-phase mixture under mutual impact, and the water mist and the nitrogen are sprayed out from the same nozzle head 42 to cool and extinguish the fire, thereby improving the atomization level of the water mist; partial nitrogen is introduced into the water channel 411 by using the plurality of air outlet holes 4121 on the gas phase channel branch pipe 412, so that the liquid is broken into large liquid drops, liquid wires and liquid films, and then is broken into small liquid drops, thereby being beneficial to improving the atomization effect at the nozzle head 42; the turbulence convex parts 4112 are arranged to increase the turbulence degree of the water in the water channel 411, so that the water is broken into small liquid drops and the atomization degree is improved; on the other hand, because the turbulence convex portion 4112 is adjacent to the gas phase passage branch pipe 412, part of the water flow can be guided to the gas outlet hole 4121, so that the interaction between the water flow and the nitrogen flowing out of the gas phase passage branch pipe 412 is facilitated, the water mist particle size of the fine water mist is reduced, and the atomization effect is improved; by the tendency that the sectional area of the water passage 411 is constant in the water flow direction, and then is reduced and finally is enlarged, the water flow rate can be increased, and negative pressure is formed at the nozzle head 42, thereby improving the atomization degree of the fine water mist. In sum, the atomization degree and the injection strength of the fine water mist are effectively improved through the gas-liquid two-phase flow nozzle 400, the efficient linkage of nitrogen and the fine water mist is realized, the injection capacity is high, the failure rate is low, the heat generated by a fire disaster can be efficiently absorbed, and the rapid cooling effect is achieved; meanwhile, combustion-supporting substances such as oxygen and the like are isolated from contacting with combustible substances, so that the occurrence and the spread of fire are inhibited; has good and rapid fire extinguishing capability and anti-reburning capability.

The embodiment realizes the high-pressure water mist effect while reducing the water mist conveying pressure based on the structure, has the advantages of strong spraying pressure, simple structure, environmental protection, no damage to equipment in the electrochemical energy storage power station and low fire extinguishing cost.

In some embodiments, a third pressure gauge 111 is connected to the line between the liquid nitrogen pump 12 and the liquid nitrogen storage tank 11, thereby enabling real-time monitoring of pressure data of the line. A liquid nitrogen flow meter 1301 is connected to the nitrogen line 130 between the liquid nitrogen pump 12 and the vaporizing device 13, thereby enabling real-time monitoring of liquid nitrogen flow data of the nitrogen line 130.

In some embodiments, as shown in fig. 2, the number of gas phase passages 413 is four; the four gas phase passages 413 are uniformly arranged in the circumferential direction of the water passage 411. For example, four gas phase passages 413 are arranged on the upper, lower, left, right of the water passage 411.

In some embodiments, the tangential direction of the outlet end of the gas phase passage 413 is at an angle of 60 ° to the direction of the central axis of the water passage 411.

In some embodiments, the shape of the air outlet holes 4121 is square.

In the process of extinguishing fire of an electrochemical energy storage power station by using the fine water mist, a part of the fine water mist droplets can be quickly vaporized, a part of the fine water mist droplets can be suspended in the air for a long time, only a small part of the fine water mist can fall onto the surface of the battery, and the fine water mist entering the internal circuit of the battery is very small. These fine mist particles entering the internal circuit of the battery are also very small in diameter, and the collection and condensation needs a very large number of mist droplets and a very long time to finish, so that it is difficult to form conductive continuous water flow or surface water area, so that the fine mist particles can be used for extinguishing fire in an electrochemical energy storage power station, but long-time fine mist spray can form conductive water flow in the internal circuit of the battery, and short circuit of the battery is caused. In response to this technical problem, in some embodiments, the electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system 1000 further comprises a humidity sensor, a controller, and a ventilation device; the electrochemical energy storage power station comprises an energy storage compartment 2000; the humidity sensor is configured to monitor humidity (and water mist concentration) within the energy storage compartment 2000; the ventilation device is configured to openably and closably exchange gas from the energy storage compartment 2000 to the outdoor environment; the controller is respectively and electrically connected with the humidity sensor, the water valve 34 and the ventilation device; the controller is configured to: when it is determined that the data of the humidity sensor is out of the preset range, the water valve 34 is controlled to be closed while keeping the gas phase passage branch 412 and the plurality of gas phase passages 413 open; the water tank 32 contains purified water.

The electrochemical energy storage power station liquid nitrogen and water mist linkage cooling fire extinguishing system 1000 based on the embodiment can reduce water mist accumulation and reduce the possibility of battery short circuit by adopting the following measures:

(1) Pure water with lower conductivity is used as a fire extinguishing medium;

(2) Monitoring humidity by a humidity sensor to confirm whether the concentration of the water mist is in a safe range, automatically closing the water valve 34 by a controller or manually closing the water valve 34 to close the water channel 411, stopping the supply of the water mist, and continuously keeping the gas phase channel branch pipe 412 and the plurality of gas phase channels 413 open to cool and extinguish the fire by low-temperature nitrogen;

(3) After the fire disaster is controlled, the ventilation device is timely started to ventilate the energy storage cabin 2000, so that the fine water mist suspended in the air can be timely discharged, the accumulation of the fine water mist is reduced, and the possibility of short circuit of the battery is reduced.

In some embodiments, a ventilation device is mounted on top of the energy storage compartment 2000, with a pressure relief valve disposed therein. The opening and closing of the relief valve is controlled based on the data from the pressure sensor 21. Specifically, when it is determined that the pressure in the energy storage compartment 2000 is higher than a preset pressure value, that is, the pressure data of the pressure sensor 21 is higher than a preset pressure value (the preset pressure value is greater than the upper limit of the aforementioned preset pressure range), the pressure release valve is opened, and ventilation and pressure release are started through the ventilation device; when it is determined that the pressure in the energy storage compartment 2000 is lower than the preset pressure value, that is, the pressure data of the pressure sensor 21 is lower than the preset pressure value and within the preset pressure range, the pressure release valve is closed, the nitrogen valve 22 is opened, and the nitrogen is recovered to release the pressure in the energy storage compartment 2000.

In some embodiments, as shown in fig. 2, a gas phase channel manifold 414 is also formed within the gas-liquid two-phase flow nozzle 400; the inlet end of the gas phase channel main pipe 414 is communicated with the pressurizing device 15; the outlet end of the gas phase channel manifold 414 communicates with the gas phase channel branch pipes 412 and the plurality of gas phase channels 413, respectively; the main body of the plurality of gas phase passages 413 extends in a straight line and is located outside the water passage 411. Thus, the gas phase channel branch pipe 412 and the plurality of gas phase channels 413 can be injected with nitrogen gas through one port of the inlet end of the gas phase channel main pipe 414, which is beneficial to reducing the size of the gas-liquid two-phase flow nozzle 400.

In some embodiments, as shown in FIG. 2, at least one air passage 415 is also formed in the nozzle body 41 at a location proximate to the nozzle tip 42; the air passage 415 is configured to communicate outside air with the gas-phase passage 413; the air passage 415 is provided with a one-way intake valve 4151. Upstream of the nozzle head 42, water accelerates in the water channel 411 (the cross-sectional area of the water channel 411 is reduced first), the water flow speed is high, negative pressure is formed at the atomizing chamber of the nozzle head 42, a pressure difference is formed between the external atmospheric pressure and the liquid pressure inside the jet section, and when the one-way air inlet valve 4151 is opened, air enters the atomizing chamber of the nozzle head 42 through the one-way air inlet valve 4151 and collides with water to form fine water mist. Therefore, the one-way air inlet valve 4151 can be opened according to actual needs, so that air enters, water mist is formed by the action of the air and water, and the supply of nitrogen is reduced or stopped, so that liquid nitrogen resources are saved, and the fire extinguishing cost is reduced.

In some embodiments, as shown in FIG. 2, a recycle nitrogen inlet valve 261 and a first thermometer 262 are also mounted on the piping between the cooler 26 and the gas mixing chamber 14. The recovered nitrogen gas inlet valve 261 is used to control the flow rate of the recovered nitrogen gas into the gas mixing chamber 14.

In some embodiments, the tank 32 contains a complex aqueous solution containing 10% potassium chloride and 10% ammonium dihydrogen phosphate. Therefore, the heat absorption capacity and the atomization capacity of the fine water mist are effectively improved, the cooling capacity of the fine water mist is improved, and the fire extinguishing speed is improved.

In some embodiments, the nozzle opening of nozzle head 42 is hexagonal in shape. Thereby, the degree of the last atomization of the water mist before the nozzle head 42 is ejected can be effectively improved.

In some embodiments, the vaporizing device 13 is an air temperature vaporizer.

In some embodiments, as shown in fig. 3 and 4, the number of gas-liquid two-phase flow nozzles 400 is a plurality; the electrochemical energy storage power station comprises an energy storage compartment 2000; a multi-layer supporting frame 500 is arranged in the energy storage cabin 2000; a plurality of battery packs 600 are layered on the multi-layered support frame 500; the plurality of gas-liquid two-phase flow nozzles 400 are disposed facing the top and side surfaces of the battery pack 600, respectively, and a preset distance is maintained between the gas-liquid two-phase flow nozzles 400 and the battery pack 600. Therefore, the gas-liquid two-phase flow nozzle 400 is arranged in the energy storage cabin 2000 in two dimensions, namely, in the vertical and horizontal directions, and meanwhile, the preset distance is kept between the gas-liquid two-phase flow nozzle 400 and the battery pack 600, so that the probability that water mist falls on the surface of the battery and enters the internal circuit of the battery is reduced while the temperature is effectively reduced and oxygen is isolated.

For example, three gas-liquid two-phase flow nozzles 400 are provided in each battery pack, two of which are horizontally placed and one of which is vertically placed, and the thermal runaway battery is subjected to fire extinguishing and temperature lowering in both horizontal and vertical directions.

In some embodiments, as shown in FIG. 1, the inlet end of the vaporizing device 13 is fitted with a liquid nitrogen inlet valve 131, and the outlet end of the vaporizing device 13 is fitted with a nitrogen outlet valve 132, a nitrogen flow meter 133, and a second thermometer 134. Thus, the flow of liquid nitrogen into vaporizing device 13 may be adjusted by adjusting liquid nitrogen inlet valve 131. The nitrogen outlet valve 132 is used for adjusting the flow rate of nitrogen flowing out of the vaporizing device 13, and further adjusting the temperature of the nitrogen flowing out of the vaporizing device 13. The faster the flow rate of nitrogen gas flowing out of the vaporizing device 13, the lower the temperature of the nitrogen gas flowing out; the slower the flow rate of nitrogen out of the vaporizing device 13, the higher the temperature of nitrogen out.

In some embodiments, as shown in fig. 1, a first pressure gauge 311 is mounted on the nitrogen manifold 31; the water outlet pipe 33 is also provided with a water flowmeter 331; a second pressure gauge 151 is also installed on the pipeline between the pressurizing device 15 and the gas-liquid two-phase flow nozzle 400; the gas phase passage 413 is provided with a nitrogen flow control valve 4131.

In some embodiments, a liquid nitrogen and water mist linked cooling fire suppression method for an electrochemical energy storage power station is provided. The method is based on the liquid nitrogen and water mist linkage cooling fire extinguishing system 1000 of the electrochemical energy storage power station, and comprises the following steps:

upon determining to start the nitrogen recovery apparatus 200, the recovered nitrogen gas inlet valve 261 is controlled according to the data of the first thermometer 262 and the second thermometer 134 to adjust the flow rate of the recovered nitrogen gas into the gas mixing chamber 14.

In some embodiments, the method comprises the steps of:

based on the measured data of the nitrogen flow meter 133 and the second thermometer 134, the liquid nitrogen inlet valve 131 is controlled to adjust the flow rate of liquid nitrogen entering the vaporizing device 13. The flow rate of nitrogen flowing out of the vaporizing device 13 is adjusted by controlling the nitrogen outlet valve 134 to control the temperature of nitrogen flowing out of the vaporizing device 13, wherein the temperature of nitrogen flowing out of the vaporizing device is above 0 degrees.

Upon determining that the data of the pressure sensor 21 is within the preset pressure range, the nitrogen valve 22 is opened to start the nitrogen recovery apparatus 200.

In some embodiments, the method further comprises the steps of:

according to the measured data of the first pressure meter 311 and the water flow meter 331, controlling the flow rate of nitrogen in the nitrogen branch pipe 31 and the water valve 34 to regulate the water flow rate in the water channel 411;

the nitrogen flow rate control valve 4131 is controlled by the pressurizing device 15 so that the pressure value of the second pressure gauge 151 reaches 0.5MPa to adjust the nitrogen flow rate in the gas phase passage 413;

the mixing ratio of nitrogen and water at the nozzle head 42 is adjusted by adjusting the water flow in the water channel 411 and the nitrogen flow in the gas phase channel 413, so as to adjust the atomization effects of the spray area, the atomization degree, the spray intensity and the like of the fine water mist sprayed by the nozzle head 42.

In the description of the above embodiments, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is merely a specific embodiment of the disclosure, but the protection scope of the disclosure is not limited thereto, and any person skilled in the art who is skilled in the art will recognize that changes or substitutions are within the technical scope of the disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. An electrochemical energy storage power station liquid nitrogen and water mist linkage cooling fire extinguishing system, which is characterized by comprising: the device comprises a nitrogen supply device, a nitrogen recovery device, a water supply device and at least one gas-liquid two-phase flow nozzle;

the nitrogen supply device comprises a liquid nitrogen pump, a liquid nitrogen storage tank, a vaporization device, a gas mixing chamber and a pressurizing device which are sequentially communicated; the gas mixing chamber is communicated with the pressurizing device through a first pipeline;

the nitrogen recovery device comprises a pressure sensor, a nitrogen valve, an induced draft device, a rotary separation device, a nitrogen purification device and a cooler which are sequentially communicated; the air outlet of the cooler is communicated with the air inlet of the gas mixing chamber;

the water supply device comprises a nitrogen branch pipe, a water tank, a water outlet pipe and a water valve; the air inlet of the nitrogen branch pipe is communicated with the first pipeline, and the air outlet of the nitrogen branch pipe is communicated with the top of the water tank; the water outlet pipe is communicated with the water tank at a position close to the bottom; the water valve is arranged on the water outlet pipe, so that water in the water tank is conveyed outwards along the water outlet pipe by utilizing the air pressure provided by the nitrogen branch pipe;

the gas-liquid two-phase flow nozzle comprises a nozzle body and a nozzle head; a water channel, a gas channel branch pipe and a plurality of gas channels are formed in the nozzle body; the inlet end of the water channel is communicated with the water outlet pipe; the gas phase passage branch pipes and the inlet ends of the gas phase passages are respectively communicated with the supercharging device; the water channel and the outlet ends of the plurality of gas phase channels are respectively communicated with the nozzle head; a plurality of the gas phase passages are uniformly arranged around the water passage; the sectional area of the water channel is unchanged in the water flow direction, and then is reduced and finally is expanded; the gas phase channel branch pipe extends along the central axis of the water channel, the end part of the gas phase channel branch pipe opposite to the inlet end of the gas phase channel branch pipe is sealed, and a plurality of air outlet holes are formed in the gas phase channel branch pipe along different directions; the air outlet holes are all positioned at the upstream of the necking part of the water channel; and a plurality of turbulence convex parts are arranged on the inner wall of the water channel and close to the gas phase channel branch pipes.

2. The electrochemical energy storage power station liquid nitrogen and water mist linkage cooling fire extinguishing system according to claim 1, wherein an included angle between a tangential direction of an outlet end of the gas phase passage and a central axis direction of the water passage is 60 degrees; the shape of the air outlet hole is square.

3. The electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system of claim 1, further comprising a humidity sensor, a controller and a ventilation device;

the electrochemical energy storage power station comprises an energy storage cabin; the humidity sensor is configured to monitor humidity within the energy storage compartment; the ventilation device is configured to openably and closably exchange gas between the energy storage compartment and an outdoor environment;

the controller is respectively and electrically connected with the humidity sensor, the water valve and the ventilation device;

the controller is configured to: when the data of the humidity sensor is determined to be out of a preset range, controlling the water valve to be closed, and simultaneously keeping the gas phase channel branch pipes and the gas phase channels open;

the water tank is filled with purified water.

4. The electrochemical energy storage power station liquid nitrogen and water mist linkage cooling fire extinguishing system according to claim 1, wherein a gas phase channel main pipe is further formed in the gas-liquid two-phase flow nozzle; the inlet end of the gas phase channel main pipe is communicated with the supercharging device; the outlet end of the gas phase channel main pipe is respectively communicated with the gas phase channel branch pipes and a plurality of gas phase channels;

the main body parts of the gas phase channels extend in a straight line and are positioned outside the water channels.

5. The electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system of claim 1, wherein at least one air passage is also formed in the nozzle body at a location proximate the nozzle head; the air passage is configured to communicate outside air with the gas-phase passage; and the air channel is provided with a one-way air inlet valve.

6. The electrochemical energy storage power station liquid nitrogen and water mist linkage cooling fire extinguishing system according to claim 1, wherein the number of the gas-liquid two-phase flow nozzles is a plurality; the electrochemical energy storage power station comprises an energy storage cabin; a multi-layer supporting frame is arranged in the energy storage cabin; a plurality of battery packs are placed on the multi-layer support frame in a layered manner;

the gas-liquid two-phase flow nozzles are respectively arranged facing the top surface and the side surface of the battery pack, and a preset distance is kept between the gas-liquid two-phase flow nozzles and the battery pack.

7. The electrochemical energy storage power station liquid nitrogen and water mist linked cooling fire suppression system of any one of claims 1 to 6, wherein the inlet end of the vaporizing device is provided with a liquid nitrogen inlet valve, and the outlet end of the vaporizing device is provided with a nitrogen outlet valve, a nitrogen flow meter and a second thermometer.

8. The liquid nitrogen and water mist linkage cooling fire extinguishing system of the electrochemical energy storage power station of claim 7, wherein a first pressure gauge is arranged on the nitrogen branch pipe; the water outlet pipe is also provided with a water flowmeter; a second pressure gauge is also arranged on a pipeline between the supercharging device and the gas-liquid two-phase flow nozzle;

and a nitrogen flow control valve is arranged on the gas phase channel.

9. A method for cooling and extinguishing fire by combining liquid nitrogen and water mist of an electrochemical energy storage power station, which is characterized by comprising the following steps based on the liquid nitrogen and water mist combined cooling and extinguishing system of the electrochemical energy storage power station as claimed in claim 7 or 8:

10. The fire suppression method according to claim 9, wherein the method further comprises the steps of: