CN117167073B - Low-temperature composite inert gas fire extinguishing system and application method thereof - Google Patents
Low-temperature composite inert gas fire extinguishing system and application method thereof Download PDFInfo
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- 239000002131 composite material Substances 0.000 title claims abstract description 75
- 239000011261 inert gas Substances 0.000 title claims abstract description 71
- 238000000034 method Methods 0.000 title claims abstract description 36
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 730
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 352
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 336
- 239000007788 liquid Substances 0.000 claims abstract description 228
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 168
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 168
- 239000007789 gas Substances 0.000 claims abstract description 129
- 238000002156 mixing Methods 0.000 claims abstract description 102
- 230000007246 mechanism Effects 0.000 claims abstract description 87
- 238000009792 diffusion process Methods 0.000 claims abstract description 14
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 claims abstract description 5
- 239000003245 coal Substances 0.000 claims description 123
- 230000001105 regulatory effect Effects 0.000 claims description 48
- 238000002485 combustion reaction Methods 0.000 claims description 22
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 21
- 230000008859 change Effects 0.000 claims description 21
- 229910001873 dinitrogen Inorganic materials 0.000 claims description 21
- 239000001301 oxygen Substances 0.000 claims description 21
- 229910052760 oxygen Inorganic materials 0.000 claims description 21
- 238000002309 gasification Methods 0.000 claims description 20
- 230000003068 static effect Effects 0.000 claims description 18
- 238000002474 experimental method Methods 0.000 claims description 16
- 230000001276 controlling effect Effects 0.000 claims description 15
- 230000009467 reduction Effects 0.000 claims description 15
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 claims description 14
- 229910001882 dioxygen Inorganic materials 0.000 claims description 14
- 230000002269 spontaneous effect Effects 0.000 claims description 14
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 claims description 13
- 238000001816 cooling Methods 0.000 claims description 12
- 238000004088 simulation Methods 0.000 claims description 10
- 230000000007 visual effect Effects 0.000 claims description 10
- 239000000203 mixture Substances 0.000 claims description 9
- DOTMOQHOJINYBL-UHFFFAOYSA-N molecular nitrogen;molecular oxygen Chemical compound N#N.O=O DOTMOQHOJINYBL-UHFFFAOYSA-N 0.000 claims description 8
- 230000007704 transition Effects 0.000 claims description 8
- 239000010425 asbestos Substances 0.000 claims description 7
- 229910052895 riebeckite Inorganic materials 0.000 claims description 7
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 6
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 claims description 6
- 239000005977 Ethylene Substances 0.000 claims description 6
- 229910002091 carbon monoxide Inorganic materials 0.000 claims description 6
- 230000008569 process Effects 0.000 claims description 6
- 230000001629 suppression Effects 0.000 claims description 5
- 238000010438 heat treatment Methods 0.000 claims description 4
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 3
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- UBAZGMLMVVQSCD-UHFFFAOYSA-N carbon dioxide;molecular oxygen Chemical compound O=O.O=C=O UBAZGMLMVVQSCD-UHFFFAOYSA-N 0.000 description 1
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Abstract
The invention discloses a low-temperature composite inert gas fire extinguishing system and a use method thereof, wherein the low-temperature composite inert gas fire extinguishing system comprises the following steps: the nitrogen conveying mechanism is used for converting liquid nitrogen into nitrogen and conveying the nitrogen into the mixing and proportioning mechanism; the carbon dioxide conveying mechanism is used for converting liquid carbon dioxide into a gaseous state and conveying the gaseous carbon dioxide into the mixing and proportioning mechanism; the mixing proportioning mechanism comprises a gas mixer, wherein the gas mixer is provided with a venturi section, a diffusion cavity connected with a carbon dioxide air inlet and a mixing pipe; the end part of the venturi tube section is connected with the nitrogen inlet, the outer side of the premixing tube in the middle part is wrapped by the diffusion cavity and communicated with each other through a plurality of cyclone tube groups, and the other end part of the venturi tube section is connected with the mixing tube; and the control system is used for controlling the flow, pressure and temperature of the corresponding medium delivery. According to the invention, the mixing effect of carbon dioxide and nitrogen is improved, so that more uniform low-temperature composite inert gas is obtained, the problem that nitrogen and carbon dioxide cannot be fully mixed in a traditional single stirring mode is avoided, and the fire extinguishing effect of the low-temperature composite inert gas is improved.
Description
Technical Field
The invention relates to a fireproof and fire extinguishing technology, belongs to the field of mine safety, and in particular relates to a low-temperature composite inert gas fire extinguishing system and a use method thereof.
Background
The spontaneous combustion fire disaster of coal is one of major disasters in coal mine production and occurs in goaf naturally, the goaf coal is caused by the fact that the coal temperature reaches the ignition point temperature due to continuous oxidation and heat accumulation of residual coal, namely a large amount of broken coal, float coal and safe coal pillars can be left in the goaf or a mining tunnel in the coal mining process, when the goaf or the mining tunnel is not tightly sealed or the ventilation condition of the tunnel is not good, oxygen is continuously supplied, a large amount of heat energy is generated after the coal is oxidized, the mine coal can be possibly spontaneous-burned due to the fact that the heat cannot be timely dissipated, and therefore the continuous supply of coal seam with spontaneous combustion tendency, the heat accumulation in the oxidation process are three factors of spontaneous combustion of the coal, and any factor in the spontaneous combustion process of the coal is broken down, so that the occurrence of the spontaneous fire disaster of the goaf coal can be inhibited;
the existing method for preventing and controlling spontaneous combustion of goaf coal mainly comprises grouting, injection of a retarder, injection of inert gas and pressure equalizing ventilation. However, in practical operation, these methods are limited by the characteristics of the coal seam and the local environment resources, and cannot be effectively implemented or achieve the expected effects, such as: the method for isolating the natural ignition position of the goaf by grouting or grouting a blocking agent is difficult to determine the position of a fire source, the action range is limited, the maximum effect of the existing technical means cannot be ensured, and the development of the technology is limited to a great extent for some mining areas lacking water sources and soil under the constraint of environmental conditions; the inert gas (nitrogen or carbon dioxide) can effectively reduce the oxygen concentration in the goaf due to the advantages of good fluidity, diffusivity, no pollution and the like, so that the inert gas is widely applied to underground fire extinguishing areas.
However, there is a certain disadvantage to using a single inert gas, such as a single nitrogen gas, which is easy to prepare although the nitrogen gas is low in cost, but the nitrogen gas density is slightly less than air, which fills the upper region of the goaf first, then covers the whole goaf from top to bottom, and the nitrogen gas in the goaf can be rapidly dissipated once the nitrogen gas injection is stopped; the single carbon dioxide is used, although the coal has stronger adsorptivity to the carbon dioxide and the fire extinguishing effect is better than that of nitrogen, the simple injection of the carbon dioxide into the goaf has the defects of difficult treatment of high-level fire sources, higher cost and the like, and the carbon dioxide concentration in the roadway airflow is easy to exceed the limit, so that the personal safety of operators is threatened;
in order to comprehensively exert the advantages of the carbon dioxide and the nitrogen in the goaf fire extinguishing work, some compound inert gases (namely, nitrogen and carbon dioxide are used in a mixed mode) are proposed and applied to the goaf fire extinguishing; however, the existing compound inert gas fire extinguishing device still has some problems and disadvantages: 1. when the temperature of the composite inert gas introduced into the goaf is high or the goaf space is large, the composite inert gas cannot be rapidly injected into each position, so that the fire extinguishing effect is reduced; 2. the traditional method mixes the carbon dioxide and the nitrogen in the mixing tank in a stirring mode, the mode not only needs an additional tank body and stirring blades and occupies a large space, but also can not fully mix the nitrogen and the carbon dioxide in a single stirring mode; 3. the spontaneous combustion in goaf tends to the coal seam burning characteristic is different, and carbon dioxide and nitrogen adopt fixed proportion ratio can't satisfy the demand of different scale coal natural ignition to in order to avoid heat accumulation, coal temperature decline rate is important when preventing and controlling to put out a fire, lack under the condition of the simulation of actual coal burning characteristic, carbon dioxide and nitrogen can't realize the quick decline of coal temperature rate.
Disclosure of Invention
The invention aims to provide a low-temperature composite inert gas fire extinguishing system, which improves the mixing effect of carbon dioxide and nitrogen, so as to obtain more uniform low-temperature composite inert gas, avoid the problem that the nitrogen and the carbon dioxide cannot be fully mixed in the traditional single stirring mode, and improve the fire extinguishing effect of the low-temperature composite inert gas;
to achieve the above object, the present invention provides a low-temperature composite inert gas fire extinguishing system, comprising:
the nitrogen conveying mechanism is connected between the liquid nitrogen tank car and the mixing and proportioning mechanism, and is used for converting liquid nitrogen into nitrogen and conveying the nitrogen into the mixing and proportioning mechanism through a nitrogen conveying pipeline;
the carbon dioxide conveying mechanism is connected between the liquid carbon dioxide tank car and the mixing and proportioning mechanism, and is used for converting liquid carbon dioxide into gas and conveying the gas into the mixing and proportioning mechanism through a gas conveying pipeline;
the mixing proportioning mechanism comprises a gas mixer, wherein the gas mixer is provided with a venturi section, a diffusion cavity connected with a carbon dioxide air inlet and a mixing pipe; the drainage tube at the end part of the venturi tube section is connected with the nitrogen inlet, the outer side of the premixing tube at the middle part is wrapped by the diffusion cavity and communicated with each other through a plurality of cyclone tube groups, and the release tube at the other end part is connected with the mixing tube;
Each cyclone tube group comprises a plurality of arc-shaped tubes circumferentially arranged in the same direction, and needles with opposite arc-shaped directions between adjacent cyclone tube groups are sequentially arranged; a plurality of cyclone plates which are arranged at intervals are arranged in the mixing pipe and close to the venturi section, and an S-shaped multi-layer baffle plate is arranged at a position far away from the venturi section and is output and connected with a composite gas conveying pipeline;
the control system is provided with a master controller, and the master controller is connected with the nitrogen conveying mechanism and the carbon dioxide conveying mechanism and is used for controlling the flow, the pressure and the temperature of the conveying of corresponding media.
In the preferred scheme, the system also comprises a coal natural simulation mechanism;
the coal nature simulation mechanism comprises:
the tank body assembly is used for correspondingly mixing oxygen with nitrogen and carbon dioxide with nitrogen according to the proportion and conveying the mixture into the coal sample experimental tank through the cooling device;
the coal sample experimental tank is internally provided with an electric heater and a sampled coal sample, the upper part of the coal sample is connected with a gas analyzer, the periphery of the coal sample experimental tank is uniformly provided with a plurality of thermocouples along the vertical direction, and the thermocouples are used for measuring the temperature changes of the coal samples at different positions and transmitting data to the acquisition device;
the gas analyzer, the acquisition device, the tank assembly and the electric heater are all connected with the master controller and controlled.
Further, the tank body component is provided with an oxygen cylinder, a nitrogen cylinder and a carbon dioxide cylinder which are respectively connected with the input end of the static mixer;
an oxygen pressure reducing valve and an oxygen flowmeter are arranged between the oxygen gas cylinder and the static mixer, a nitrogen pressure reducing valve and a nitrogen flowmeter are arranged between the nitrogen gas cylinder and the static mixer, and a carbon dioxide pressure reducing valve and a carbon dioxide flowmeter are arranged between the carbon dioxide gas cylinder and the static mixer;
the lower part of the coal sample experimental tank is provided with a filter screen, and the upper part is provided with filter asbestos.
In a preferred scheme, the nitrogen conveying mechanism is provided with a liquid nitrogen booster pump and an air temperature gasifier I;
the output end of the liquid nitrogen tank car 7 is sequentially connected with a liquid nitrogen conveying pipeline, a liquid nitrogen booster pump, a liquid nitrogen booster pipeline and the input end of the air temperature gasifier I, and the output end of the air temperature gasifier I is connected with the nitrogen conveying pipeline;
the carbon dioxide conveying mechanism is provided with an air temperature gasifier II;
the output end of the liquid carbon dioxide tank car is sequentially connected with a liquid conveying pipeline and the input end of the air-temperature gasifier II, and the output end of the air-temperature gasifier II is connected with a gaseous conveying pipeline.
Further, the control system also comprises a flow control device, a temperature control device and a pressure control device;
The flow control device is provided with a pneumatic regulating valve I and a turbine flowmeter I which are arranged on a nitrogen conveying pipeline, and a pneumatic regulating valve II and a turbine flowmeter II which are arranged on a gaseous conveying pipeline, wherein the turbine flowmeter I is matched with a flow transmitter I and transmits flow data to a PLC (programmable logic controller) III, and the turbine flowmeter II is matched with the flow transmitter II and transmits the flow data to a PLC V; the master controller correspondingly controls the opening of the pneumatic regulating valve I and the opening of the pneumatic regulating valve II through the PLC III and the PLC V;
the temperature control device is provided with a low-temperature electric valve I and a thermometer I which are arranged on a liquid nitrogen pressurizing pipeline, a thermometer II and a matched temperature transmitter I which are arranged on a nitrogen conveying pipeline, a thermometer IV and a matched temperature transmitter II which are arranged on a gaseous conveying pipeline, and a temperature transmitter III which is arranged on a composite gas conveying pipeline; the master controller receives signals of the temperature transmitter I and the temperature transmitter II, correspondingly controls the opening of the low-temperature electric valve I and the opening of the low-temperature electric valve II positioned on the liquid conveying pipeline to form a cascade control adjusting inner ring, and receives signals of the temperature transmitter III to control the opening of the low-temperature electric valve I to form a cascade control adjusting outer ring;
The pressure control device is provided with a pressure gauge IV arranged on a liquid nitrogen pressurizing pipeline, a matched pressure transmitter I, a pressure gauge VI arranged on a nitrogen conveying pipeline, a matched pressure transmitter III, a pressure gauge VIII arranged on a gaseous conveying pipeline and a matched pressure transmitter IV; the master controller receives signals of the pressure transmitter I, controls the safety valve II on the liquid nitrogen booster pump and the liquid nitrogen booster pipeline, receives signals of the pressure transmitter III, controls the safety valve III on the nitrogen conveying pipeline, and receives signals of the pressure transmitter IV to control the safety valve IV on the gaseous conveying pipeline.
Further, a one-way valve I, a low-temperature long-axis stop valve III and a pressure gauge V are sequentially arranged on the liquid nitrogen pressurizing pipeline from the liquid nitrogen pressurizing pump to the air temperature gasifier I;
the nitrogen conveying pipeline is further provided with a low Wen Duanzhou stop valve I, a pressure regulating valve I and a one-way valve II in sequence from the air-temperature gasifier I to the mixing and proportioning mechanism, and an audible and visual alarm I is matched at the pressure transmitter III;
a low-temperature long-axis stop valve IV is arranged on the liquid conveying pipeline, and a low Wen Duanzhou stop valve II, a pressure regulating valve II and a one-way valve III are arranged on the gaseous conveying pipeline from the air-temperature gasifier II to the mixing ratio mechanism; and an audible and visual alarm II is matched at the IV position of the pressure transmitter.
Further, a pressure gauge I9, a low-temperature long-axis stop valve I, a filter, a pressure gauge II and a safety valve I are sequentially arranged on the liquid nitrogen conveying pipeline from the liquid ammonia tank car to the booster pump;
the upstream of the liquid nitrogen booster pump is connected to the liquid nitrogen tank car through a nitrogen return pipeline;
the nitrogen return pipeline is provided with a low-temperature long-shaft stop valve II and a pressure gauge III from the liquid nitrogen booster pump to the liquid nitrogen tank car.
Further, the system is positioned in a bottom pry box body of the mobile car body;
the upper part of the bottom pry box body is provided with a plurality of convection air fans which are correspondingly positioned above the nitrogen conveying mechanism and the carbon dioxide conveying mechanism.
The invention also aims to provide a using method of the low-temperature composite inert gas fire extinguishing system, which is characterized in that the burning characteristics of an actual coal sample are analyzed, the ratio of carbon dioxide to nitrogen under the condition of the fastest coal temperature drop rate is obtained through multiple experiments, and the carbon dioxide and the nitrogen are fully mixed in a gas mixer, so that the fire extinguishing effect of the low-temperature composite inert gas is improved;
the application method of the low-temperature composite inert gas fire extinguishing system specifically comprises the following steps:
s1: determining the mixing ratio of the composite inert gas
Extracting and sampling coal in the goaf;
a1. Placing the extracted coal sample in a coal sample experimental tank, opening an oxygen gas cylinder and a nitrogen gas cylinder, adjusting an oxygen flow meter and a nitrogen flow meter to ensure that the mixing proportion of the oxygen gas cylinder and the nitrogen flow meter is consistent with the nitrogen-oxygen proportion of the actual environment of the goaf, and uniformly mixing the two gases through a static mixer;
a2. the electric heater is turned on, the real-time heating temperature is set, the air mixture obtained in the a1 is led into the coal sample experimental tank through the filter screen at normal temperature, the gas reacted with the coal sample is filtered through the filter stone cotton, the gas product change is monitored in real time through the gas analyzer, the temperature change of the coal sample at different positions is monitored in real time through the thermocouple, and the data are recorded in real time through the acquisition device;
a3. after the electric heater heats for a period of time, the oxygen gas cylinder and the electric heater are closed, the carbon dioxide gas cylinder is opened, the carbon dioxide flowmeter and the nitrogen flowmeter are regulated to enable the mixing proportion of the carbon dioxide flowmeter and the nitrogen flowmeter to be the first experimental proportion set in experiments, the cooling device is opened, so that the mixed gas enters the coal sample experimental tank at low temperature, and the temperature change of the coal sample and the change condition of gas products are monitored in real time until the temperature is reduced to below 0 ℃;
a4. changing a new coal sample, changing the mixing proportion of carbon dioxide and nitrogen in the step a3, and repeating the operations of a1, a2 and a 3;
a5. According to the coal temperature reduction rate of the coal sample under different carbon dioxide and nitrogen ratios and the carbon monoxide/methane/ethylene index gas concentration reduction rate parameter generated by spontaneous combustion, selecting the carbon dioxide and nitrogen ratio with the fastest coal temperature index gas concentration reduction rate as the final composite inert gas mixing ratio;
s2: liquid nitrogen gasification control method
The low-temperature composite inert gas fire extinguishing system is moved to the vicinity of a local fire disaster, and the liquid nitrogen tank car and the liquid carbon dioxide tank car are reasonably regulated according to the actual fire disaster condition of the site;
a. the liquid nitrogen is conveyed from a liquid nitrogen inlet to a liquid nitrogen booster pump from the liquid nitrogen tank car along a liquid nitrogen conveying pipeline in the downstream direction, and is supplied;
b. after the pressurized liquid nitrogen flows out from the liquid nitrogen booster pump, the pressurized liquid nitrogen is conveyed into the air temperature gasifier I through the liquid nitrogen booster pump and the liquid nitrogen booster pipeline;
meanwhile, the pressure gauge IV is used for detecting the pressure of the liquid nitrogen passing through the liquid nitrogen booster pump, and the temperature gauge I is used for detecting the temperature of the passing liquid nitrogen; when the pressure does not reach the preset pressure, the master controller controls the pressure of the liquid nitrogen booster pump, and when the detected pressure is greater than the maximum allowable pressure, the safety valve II performs safety pressure relief;
c. the liquid nitrogen flowing in from the liquid nitrogen conveying pipeline is partially gasified in the liquid nitrogen booster pump, and generated nitrogen sequentially enters a nitrogen return port on the liquid nitrogen tank wagon storage tank through a nitrogen return pipeline, so that the pressure balance between the liquid nitrogen tank wagon storage tank and the liquid nitrogen booster pump is completed;
d. The liquid nitrogen is gasified in an isobaric way through an air-temperature gasifier I;
the master controller adjusts and controls the gasification liquid inlet amount of the liquid nitrogen by adjusting the opening of the low-temperature electric valve I, so as to control the temperature of the gasified liquid nitrogen;
e. the gasified nitrogen is delivered to a pneumatic regulating valve I through a nitrogen delivery pipeline, and the pneumatic regulating valve I regulates the nitrogen pressure;
the temperature gauge II detects the temperature of nitrogen passing through the air-temperature gasifier I, the pressure gauge VI detects the pressure of the nitrogen passing through the air-temperature gasifier I, and the safety valve III carries out safety pressure relief when the detected pressure is greater than the maximum allowable pressure;
s3: liquid carbon dioxide gasification control method
a. The liquid carbon dioxide is conveyed from a liquid carbon dioxide tank car to an air-temperature gasifier II from a liquid carbon dioxide inlet to the downstream along a liquid conveying pipeline to finish isobaric gasification;
b. the gasified carbon dioxide gas is conveyed to a pressure regulating valve II through a gaseous conveying pipeline, and the pressure of the carbon dioxide gas is regulated by the pressure regulating valve II;
meanwhile, a thermometer IV detects the temperature of carbon dioxide passing through the air-temperature gasifier II, a pressure meter VIII detects the pressure of the carbon dioxide passing through the air-temperature gasifier II, and when the detected pressure is greater than the maximum allowable pressure, a safety valve IV carries out safety pressure relief;
S4: low-temperature composite inert gas proportioning control method
a. Inputting the final composite inert gas mixing proportion in the step S1 into a control system, controlling the flow of nitrogen by a master controller through adjusting a pneumatic adjusting valve I, controlling the flow of carbon dioxide by adjusting a pneumatic adjusting valve II, and collecting the instantaneous flow proportion and the accumulated flow proportion in real time;
b. nitrogen enters a premixing tube of a venturi tube section from a nitrogen inlet, carbon dioxide enters a diffusion cavity from a carbon dioxide inlet, and enters the premixing tube through a cyclone tube to be premixed with the nitrogen in the premixing tube, the premixed gas enters a transition mixing section and is subjected to transition mixing through a plurality of cyclone plates, finally enters a full mixing section, and is discharged from a mixed gas outlet and a composite gas conveying pipeline after being fully mixed through a baffle plate;
the temperature transmitter III monitors the temperature of the low-temperature composite inert gas in real time and feeds the temperature back to the master controller;
if the temperature of the composite inert gas is higher than the set outlet temperature, the master controller controls the low-temperature electric valve I to increase the gasification amount of liquid nitrogen and form temperature cascade control with the temperature of the nitrogen gasification process;
c. the low-temperature composite inert gas is conveyed to the ignition area by a pipeline.
Compared with the prior art, the low-temperature composite inert gas fire extinguishing system has the advantages that as the gas mixer is sequentially arranged through the needles with the arc directions opposite to each other between the adjacent cyclone tube groups, the mixing effect of carbon dioxide and nitrogen in the premixing tube is greatly improved, the flow direction of the gas is continuously changed by sequentially passing through the plurality of cyclone plates and the S-shaped multilayer baffle plates, the residence time of the gas in the flow passage is prolonged, the nitrogen and the carbon dioxide are fully mixed, and therefore, more uniform low-temperature composite inert gas is obtained, the occupied space is small, and the situation that the nitrogen and the carbon dioxide cannot be fully mixed in a traditional single stirring mode is avoided;
the coal natural simulation mechanism is arranged, the actual coal sample combustion condition is simulated by mixing the oxygen and the nitrogen in proportion, carbon dioxide and the nitrogen are correspondingly introduced into the coal sample experiment tank according to a certain proportion to perform fire extinguishing simulation, the combustion characteristics of the actual coal sample are analyzed, the mixture ratio of the carbon dioxide and the nitrogen under the condition that the concentration of the coal temperature and the index gas is reduced at the highest rate is obtained through multiple experiments, and the amount of the introduced carbon dioxide and the nitrogen in the actual mixing and proportioning mechanism is controlled based on the mixture ratio, so that fire extinguishing is more targeted, the rapid reduction of the coal temperature rate is realized, and heat accumulation is avoided;
The control system is arranged and further comprises a flow control device, a temperature control device and a pressure control device, wherein the master controller receives signals of the temperature transmitter I and the temperature transmitter II, correspondingly controls the opening of the low-temperature electric valve I and the opening of the low-temperature electric valve II to form a cascade control adjusting inner ring, receives signals of the temperature transmitter III, controls the opening of the low-temperature electric valve I to form a cascade control adjusting outer ring, realizes multistage adjusting control on fire extinguishing temperature, rapidly responds to the outlet temperature of the nitrogen gasifier according to a temperature set value, and ensures stable low-temperature composite inert gas output;
the nitrogen conveying mechanism and the carbon dioxide conveying mechanism are respectively connected with the mixing proportioning mechanism, and the main controller controls the flow, the pressure and the temperature of the corresponding medium conveying, so that single or common conveying can be selected according to the actual conditions of the site, the control requirements of natural ignition of different-scale coals are met, and the composite inert gas can be rapidly injected to each position through the pressure control device, so that the fire extinguishing effect is improved; the fire extinguishing system can be applied to underground coal mine fire extinguishment and ground fire extinguishing areas, and the application range of the fire extinguishing system is widened.
Drawings
FIG. 1 is a connection flow diagram of the present invention;
FIG. 2 is a schematic view of the structure of the present invention on a mobile vehicle body;
FIG. 3 is a schematic view of the structure of the invention with a bottom pry box on the mobile car body;
FIG. 4 is a control flow diagram of the present invention;
FIG. 5 is a schematic diagram of the compound inert gas proportioning structure of the present invention;
FIG. 6 is a schematic view of a gas mixer according to the present invention;
in the figure: 1. the control system, 2, nitrogen conveying mechanism, 3, carbon dioxide conveying mechanism, 4, mixing proportioning mechanism;
5. a bottom pry box body, 6, a convection exhaust fan;
7. the device comprises a liquid nitrogen tank car, 8, metal hoses I and 9, pressure gauges I and 10, a low-temperature long shaft I and 11, a filter, 12, pressure gauges II and 13, safety valves I and 14, metal hoses II and 15, a liquid nitrogen booster pump, 16, metal hoses III and 17, a low-temperature long shaft II and 18, pressure gauges III and 19, a liquid nitrogen conveying pipeline, 20, a nitrogen return pipeline, 21, metal hoses IV and 22, one-way valves I and 23, pressure gauges IV and 24, a low-temperature long shaft III and 25, safety valves II and 26, a pressure transmitter I and 27 and a PLC controller I, 28, a liquid nitrogen pressurizing pipeline, 29, a low-temperature electric valve I, 30, a pressure gauge V, 31, a thermometer I, 32, an air-temperature gasifier I, 33, a thermometer II, 34, a pressure gauge VI, 35, a temperature transmitter I, 36, a PLC controller II, 37, a safety valve III, 38, a low Wen Duanzhou stop valve I, 39, a pressure regulating valve I, 40, a pressure transmitter III, 41, an audible and visual alarm I, 42, a nitrogen conveying pipeline, 43, a pneumatic regulating valve I, 44, a PLC controller III, 45, a flow transmitter I, 46, a turbine flowmeter I, 47 and a one-way valve II;
48. Liquid carbon dioxide tank car, 49, metal hose v, 50, low temperature long axis stop valve iv, 51, low temperature electric valve ii, 52, pressure gauge vii, 53, thermometer iii, 54, air temperature gasifier ii, 55, PLC controller iv, 56, thermometer iv, 57, pressure gauge viii, 58, temperature transmitter ii, 59, safety valve iv, 60, low Wen Duanzhou stop valve ii, 61, pressure regulating valve ii, 62, pressure transmitter iv, 63, audible and visual alarm ii, 64, pneumatic regulating valve ii, 65, turbine flowmeter ii, 66, check valve iii, 67, flow transmitter ii, 68, PLC controller v, 69, liquid conveying pipeline, 70, gaseous conveying pipeline;
71. the device comprises a gas mixer 72, pressure gauges IX and 73, PLC controllers VI and 74, temperature transmitters III and 75, butterfly valves 76, a compound nitrogen delivery port 77 and a compound gas delivery pipeline;
78. oxygen gas cylinder, 79, nitrogen gas cylinder, 80, carbon dioxide gas cylinder, 81, oxygen pressure reducing valve, 82, nitrogen pressure reducing valve, 83, carbon dioxide pressure reducing valve, 84, static mixer, 85, cooling device, 86, coal sample experimental tank, 87, gas analyzer, 88, oxygen flowmeter, 89, nitrogen flowmeter, 90, carbon dioxide flowmeter, 91, filter asbestos, 92, thermocouple, 93, electric heater, 94, collection device, 95, filter screen, 96, heat preservation shell, 97, expansion throttle valve, 98, compressor, 99, absolute ethyl alcohol tank, 100, condenser, 101, general controller;
102. Nitrogen inlet 103, carbon dioxide inlet 104, venturi section 105, diffusion chamber 106, draft tube 107, premix tube 108, release tube 109, swirl tube set 110, swirl plate 111, baffle 112, and mixed gas outlet.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
As shown in fig. 1 and 6, the low-temperature composite inert gas fire extinguishing system comprises:
the nitrogen conveying mechanism 2 is connected between the liquid nitrogen tank car 7 and the mixing and proportioning mechanism 4, and is used for converting liquid nitrogen into nitrogen and conveying the nitrogen into the mixing and proportioning mechanism 4 through a nitrogen conveying pipeline 42;
the carbon dioxide conveying mechanism 3 is connected between the liquid carbon dioxide tank car 48 and the mixing and proportioning mechanism 4, and is used for converting the liquid carbon dioxide into a gas state and conveying the gas state into the mixing and proportioning mechanism 4 through a gas conveying pipeline 70;
The mixing and proportioning mechanism 4 is connected with a compound gas delivery pipeline 77 at the output end and comprises a gas mixer 71, wherein the gas mixer 71 is provided with a venturi section 104, a diffusion cavity 105 connected with a carbon dioxide gas inlet 103 and a mixing pipe; a drainage tube 106 at the end part of the venturi tube section 104 is connected with the nitrogen gas inlet 102, the outer side of a premixing tube 107 in the middle part is wrapped by a diffusion cavity 105 and communicated with each other through a plurality of swirl tube groups 109, and a release tube 108 at the other end part is connected with the mixing tube;
the diffusion chamber 105 is wrapped and arranged on the outer side of the premixing tube 107 and is communicated with the inside of the premixing tube 107 through a plurality of groups of swirl tube groups 109, each swirl tube group 109 comprises a plurality of arc-shaped tubes circumferentially arranged in the same direction, and needles with opposite arc-shaped directions between adjacent swirl tube groups 109 are sequentially arranged; a plurality of cyclone plates 110 which are arranged at intervals are arranged in the mixing pipe near the venturi section 104, and S-shaped multi-layer baffle plates 111 are arranged at positions far away from the venturi section 104;
the control system 1 is provided with a master controller 101, and the master controller 101 is connected with the nitrogen conveying mechanism 2 and the carbon dioxide conveying mechanism 3 and is used for controlling the flow, the pressure and the temperature of the conveying of corresponding media;
specifically, the nitrogen conveying mechanism 2 is used for converting liquid nitrogen into nitrogen and introducing the nitrogen into the mixing and proportioning mechanism 4, and the carbon dioxide conveying mechanism 3 is used for converting liquid carbon dioxide into a gaseous state and introducing the liquid carbon dioxide into the mixing and proportioning mechanism 4;
The mixing and proportioning mechanism 4 can ensure the full mixing of the nitrogen and the carbon dioxide, namely the gas mixer 71 can be divided into a premixing section, a transitional mixing section and a full mixing section, the venturi section 104 is positioned in the premixing section and comprises a drainage tube 106 for guiding the gas flow to enter, a premixing tube 107 for preliminary mixing and a release tube 108 for stably discharging the mixed gas, and preferably, the minimum contracted cross-section diameter of the premixing tube 107 is 70-80% of the gaseous conveying pipeline with the diameter of the nitrogen gas inlet 102; the swirl tube groups 109 are three groups, each group is provided with 8 arc-shaped tubes which are circumferentially arranged in the same direction, and the elbows of the three-row carbon dioxide swirl tube groups 109 are respectively arranged in a clockwise-anticlockwise-clockwise direction relative to the normal direction of the nitrogen gas inlet 102;
the cyclone plate 110 is positioned at the transition mixing section, and the S-shaped multi-layer baffle plate 111 is positioned at the full mixing section;
the master controller 101 can adopt an industrial PLC (programmable logic controller) which integrally controls all components of the nitrogen conveying mechanism 2, the carbon dioxide conveying mechanism 3 and the mixing proportioning mechanism 4, and each of the nitrogen conveying mechanism 2 and the carbon dioxide conveying mechanism 3 comprises a PLC controller which independently controls corresponding components and is connected with the master controller 101;
When the low-temperature composite inert gas fire extinguishing system is used, the nitrogen conveying mechanism 2 is connected with the liquid nitrogen tank car 7, liquid nitrogen is converted into nitrogen and conveyed into the mixing and proportioning mechanism 4, the carbon dioxide conveying mechanism 3 is connected with the liquid carbon dioxide tank car 48, liquid carbon dioxide is converted into gaseous carbon dioxide and conveyed into the mixing and proportioning mechanism 4, namely, nitrogen enters the premixing tube 107 of the venturi tube section 104 from the nitrogen gas inlet 102, carbon dioxide enters the diffusion cavity 105 from the carbon dioxide gas inlet 103 and enters the premixing tube 107 through the swirl tube to be premixed with the nitrogen therein, the premixed gas enters the transition mixing section again and is subjected to transition mixing through the swirl plates 110, and finally enters the full mixing section, is fully mixed through the baffle plates 111 and is discharged from the mixed gas outlet 112 and the composite gas conveying tube 77;
the mixing proportioning mechanism 4 is sequentially arranged through the needles with opposite arc directions between the adjacent cyclone tube groups 109, so that the mixing effect of carbon dioxide and nitrogen in the premixing tube 107 is greatly improved, the airflow continuously changes the flowing direction through the cyclone plates 110 and the S-shaped multi-layer baffle plates 111, the residence time of the air in the flow channel is increased, the nitrogen and the carbon dioxide are fully mixed, and therefore, more uniform low-temperature composite inert gas is obtained, the occupied space is small, and the situation that the nitrogen and the carbon dioxide cannot be fully mixed in a traditional single stirring mode is avoided.
In a preferred embodiment, as shown in FIG. 5, the present fire suppression system further comprises a coal natural simulation mechanism;
the coal nature simulation mechanism comprises:
the tank body assembly is used for correspondingly mixing oxygen and nitrogen, and correspondingly mixing carbon dioxide and nitrogen according to the proportion, and conveying the mixture into the coal sample experimental tank 86 through the cooling device 85;
the coal sample experimental tank 86 is internally provided with an electric heater 93 and a gas analyzer 87 connected with the extracted coal sample and the upper part;
thermocouples 92 located at a plurality of positions along the vertical direction of the circumference of the coal sample experimental tank 86 for measuring the temperature change of the coal samples at different positions and transmitting the data to a collecting device 94;
the gas analyzer 87, the collection device 94, the tank assembly and the electric heater 93 are all connected with the master controller 101 and controlled;
further, the tank assembly is provided with an oxygen cylinder 78, a nitrogen cylinder 79 and a carbon dioxide cylinder 80 which are respectively connected with the input end of the static mixer 84;
an oxygen pressure reducing valve 81 and an oxygen flow meter 88 are arranged between the oxygen gas bottle 78 and the static mixer 84, a nitrogen pressure reducing valve 82 and a nitrogen flow meter 89 are arranged between the nitrogen gas bottle 79 and the static mixer 84, and a carbon dioxide pressure reducing valve 83 and a carbon dioxide flow meter 90 are arranged between the carbon dioxide gas bottle 80 and the static mixer 84;
The lower part of the coal sample experiment tank 86 is provided with a filter screen 95, and the upper part is provided with a filter asbestos 91;
specifically, the tank assembly is configured to store a certain amount of oxygen, carbon dioxide and nitrogen respectively, and introduce the oxygen, the nitrogen and the carbon dioxide into the coal sample experimental tank 86 according to a certain proportion, so as to simulate the nitrogen-oxygen proportion in the air and the nitrogen-carbon dioxide proportion in the mixing and proportioning mechanism 4 correspondingly, so as to perform combustion and fire extinguishing simulation on the coal sample;
the cooling device 85 is used for cooling the mixed gas of carbon dioxide and nitrogen, and may have an absolute ethanol tank 99 and a condenser 100; the output pipeline of the absolute ethyl alcohol tank 99 is connected with the input end of a condenser 100 through a compressor 98, and the output end of the condenser 100 is connected with an expansion throttle valve 97 and then flows back into the absolute ethyl alcohol tank 99 through the input pipeline; the output pipeline of the static mixer 84 is connected to the lower end of the coal sample experimental tank 86 after passing through the absolute ethyl alcohol tank 99;
namely, the medium in the absolute ethyl alcohol tank 99 has good cooling effect so as to simulate the corresponding fire extinguishing temperature, and the medium flows back to the absolute ethyl alcohol tank 99 through the compressor 98 and the condenser 100 so as to ensure the circulating cooling;
the outside of the coal sample experiment tank 86 is wrapped with a heat preservation shell 96, an electric heater 93 is arranged below the coal sample experiment tank 86, 9 thermocouples 92 are uniformly arranged around the coal sample experiment tank along the vertical direction, and the upper part of the coal sample experiment tank 86 and a gas analyzer 87 are communicated together through stainless steel pipelines; the acquisition device 94 is used for recording the temperature change and the gas concentration change of the thermocouple 92 in real time;
When the optimal scheme works, the extracted coal sample is placed in a coal sample experiment tank 86, an oxygen gas cylinder 78 and a nitrogen gas cylinder 79 are opened, an oxygen flow meter 88 and a nitrogen flow meter 89 are adjusted to enable the mixing proportion of the extracted coal sample and the nitrogen-oxygen ratio of the actual environment of the goaf to be matched, the two gases are uniformly mixed through a static mixer 84, and the nitrogen-oxygen ratio can be adjusted through corresponding flow meters to be matched with the actual environment of the goaf;
the electric heater 93 is turned on, the real-time heating temperature is set, for example, 500 ℃, the nitrogen-oxygen mixed gas is led into the coal sample experimental tank 86 through the filter screen 95 at normal temperature, the gas reacted with the coal sample is filtered through the filter asbestos 91, the gas product change is monitored in real time through the gas analyzer 87, the temperature change of the coal sample at different positions is monitored in real time through the thermocouple 92, and the data is recorded in real time through the acquisition device 94;
after the electric heater 93 heats for a period of time, the oxygen gas bottle 78 and the electric heater 93 are closed, the carbon dioxide gas bottle 80 is opened, the carbon dioxide flowmeter 90 and the nitrogen flowmeter 89 are regulated to make the mixing proportion be a first set of experimental proportion set by experiments, the cooling device 85 is opened, the temperature of the mixed gas entering the coal sample experimental tank 86 is ensured to be in line with the fire extinguishing system, for example, the temperature of-30 ℃, and the temperature change of the coal sample and the change condition of a gas product are monitored in real time until the temperature is reduced to below 0 ℃;
When the combustion of the coal sample is completed, replacing a new coal sample and the mixing ratio of carbon dioxide and nitrogen, repeating the above operation, wherein the master controller 101 can comprise analysis instruments such as a computer and the like, and analyze data of the combustion characteristics of the coal sample under different ratios of carbon dioxide and nitrogen, namely, according to the coal temperature reduction rate of the coal sample under different ratios of carbon dioxide and nitrogen and the carbon monoxide/methane/ethylene index gas concentration reduction rate parameters generated by spontaneous combustion, selecting the carbon dioxide and nitrogen ratio with the fastest coal temperature index gas concentration reduction rate as the final composite inert gas mixing ratio; the spontaneous combustion of coal in the goaf is a smoldering combustion, so that the spontaneous combustion test or the combustion test of the coal is incomplete combustion, namely, the coal sample is ignited under the nitrogen-oxygen ratio to generate gases such as carbon monoxide, methane, ethylene and the like, at the moment, the gas analyzer 87 detects and analyzes the concentrations of index gases such as carbon monoxide, methane, ethylene and the like, and transmits the concentrations to the acquisition device 94 for recording to obtain the falling rate of the concentrations of the index gases, and the ratio of carbon dioxide and nitrogen with the fastest falling rate of the concentrations of the coal temperature index gases is selected as the final composite inert gas mixing ratio;
At this time, the master controller 101 controls the pneumatic control valve i 43 for controlling the nitrogen to enter the gas mixer 71 and the pneumatic control valve ii 64 for controlling the carbon dioxide to enter the gas mixer 71, and the carbon dioxide and the nitrogen are mixed in the mixing and proportioning mechanism 4 according to the corresponding proportion, and finally discharged from the composite nitrogen delivery port 76 to extinguish fire and prevent spontaneous combustion;
according to the optimal scheme, the combustion characteristics of the coal sample in practice are analyzed, the ratio of carbon dioxide to nitrogen is obtained through multiple experiments under the condition that the coal temperature reduction rate is the fastest, and the amount of carbon dioxide and nitrogen introduced into the actual mixing and proportioning mechanism 4 is controlled based on the ratio, so that fire extinguishment is more targeted, the rapid reduction of the coal temperature rate is realized, and heat accumulation is avoided.
As shown in fig. 1 and 4, the nitrogen gas delivery mechanism 2 preferably has a liquid nitrogen booster pump 15 and an air temperature gasifier i 32;
the output end of the liquid nitrogen tank car 7 is sequentially connected with a liquid nitrogen conveying pipeline 19, a liquid nitrogen booster pump 15, a liquid nitrogen booster pipeline 28 and the input end of an air temperature gasifier I32, and the output end of the air temperature gasifier I32 is connected with a nitrogen conveying pipeline 42;
the carbon dioxide conveying mechanism 3 is provided with an air temperature gasifier II 54;
The output end of the liquid carbon dioxide tank wagon 48 is sequentially connected with a liquid conveying pipeline 69 and an air temperature gasifier II 54, and the output end of the air temperature gasifier II 54 is connected with a gaseous conveying pipeline 70;
specifically, the liquid nitrogen booster pump 15 is used for adjusting the pressure during liquid nitrogen delivery so as to avoid insufficient pressure during long-distance delivery; the air temperature gasifier I32 and the air temperature gasifier II 54 are respectively used for completely gasifying liquid nitrogen and liquid carbon dioxide at equal pressure;
in addition, preferably, both ends of the liquid nitrogen conveying pipeline 19 are respectively connected with the liquid nitrogen tank wagon 7 and the liquid nitrogen booster pump 15 through the metal hose I8 and the metal hose II 14, a metal hose V49 is connected between the liquid carbon dioxide tank wagon 48 and the liquid conveying pipeline 69, and a metal hose IV 21 is connected between the liquid nitrogen booster pump 15 and the liquid nitrogen booster pipeline 28.
Further, the control system 1 further comprises a flow control device, a temperature control device and a pressure control device;
the flow control device comprises a pneumatic regulating valve I43 and a turbine flowmeter I46 which are arranged on the nitrogen conveying pipeline 42, and a pneumatic regulating valve II 64 and a turbine flowmeter II 65 which are arranged on the gas conveying pipeline 70, wherein the turbine flowmeter I46 is matched with a flow transmitter I45 and transmits flow data to a PLC controller III 44, and the turbine flowmeter II 65 is matched with a flow transmitter II 67 and transmits the flow data to a PLC controller V68; the master controller 101 controls the opening of the pneumatic control valve I43 and the pneumatic control valve II 64 correspondingly with the PLC V68 through the PLC III 44;
The temperature control device comprises a low-temperature electric valve I29 and a thermometer I31 which are arranged on a liquid nitrogen pressurizing pipeline 28, a thermometer II 33 and a matched temperature transmitter I35 which are arranged on a nitrogen conveying pipeline 42, a thermometer IV 56 and a matched temperature transmitter II 58 which are arranged on a gaseous conveying pipeline 70, and a temperature transmitter III 74 which is arranged on a composite gas conveying pipeline 77; the master controller 101 receives signals of the temperature transmitter I35 and the temperature transmitter II 58, correspondingly controls the opening of the low-temperature electric valve I29 and the opening of the low-temperature electric valve II 51 positioned on the liquid conveying pipeline 69 to form an adjusting inner ring of cascade control, and the master controller 101 receives signals of the temperature transmitter III 74 and controls the opening of the low-temperature electric valve I29 to form an adjusting outer ring of cascade control;
the pressure control device comprises a pressure gauge IV 23 arranged on the liquid nitrogen pressurizing pipeline 28, a matched pressure transmitter I26, a pressure gauge VI 34 arranged on the nitrogen conveying pipeline 42, a matched pressure transmitter III 40, a pressure gauge VIII 57 arranged on the gaseous conveying pipeline 70 and a matched pressure transmitter IV 62; the master controller 101 controls the safety valve II 25 on the liquid nitrogen booster pump 15 and the liquid nitrogen booster pipeline 28 by receiving the signal of the pressure transmitter I26, controls the safety valve III 37 on the nitrogen delivery pipeline 42 by receiving the signal of the pressure transmitter III 40, and controls the safety valve IV 59 on the gaseous delivery pipeline 70 by receiving the signal of the pressure transmitter IV 62.
Specifically, each safety valve is used for safety pressure relief, the pressure gauge and the temperature gauge are correspondingly used for detecting the pressure and the temperature of a medium passing through a corresponding pipeline, and the pressure transmitter, the temperature transmitter and the flow transmitter are used for converting the detected pressure, the detected temperature and the detected flow of the medium into analog signals for transmission;
the low-temperature electric valve I29 adjusts the liquid nitrogen temperature passing through the liquid nitrogen pressurizing pipeline 28 to enable gasified nitrogen to be introduced into the mixed proportioning mechanism 4 to have a certain low temperature, the low-temperature electric valve II 51 adjusts the liquid carbon dioxide passing through the liquid conveying pipeline 69 to enable gasified carbon dioxide to be introduced into the proportioning mechanism to have a certain low temperature, the temperature transmitter III 74 carries out data conversion on the temperature of the mixed gas on the composite gas conveying pipeline 77, the PLC controller VI 73 controls the low-temperature electric valve I29 to realize multi-stage control on the temperature, namely, cascade control on the temperature is realized through coarse adjustment and fine adjustment, the outlet temperature of the nitrogen gasifier can be adjusted according to the temperature set value in a quick response mode, the outlet temperature of the composite inert gas can accurately and quickly reach the set value, and stable low-temperature (-30 ℃) composite inert gas is ensured to be output;
The flow control device can be matched and connected with the CO and CH4 gas sensor and the temperature sensor of the ignition area, and can monitor CO and CH in real time according to the fire extinguishment site 4 The flow of the injected composite inert gas is regulated according to the gas concentration and the temperature change trend, so that closed-loop self-adaptive intelligent regulation of the flow is realized, and the cost can be saved while the fire is effectively extinguished; the turbine flowmeter I46 detects the flow of the passing nitrogen, the turbine flowmeter II 65 detects the flow of the passing gaseous carbon dioxide, and the opening of the pneumatic regulating valve I43 and the opening of the pneumatic regulating valve II 64 are correspondingly controlled so as to realize the adjustment of the proportion of the gas before the mixing and proportioning mechanism 4;
the pressure transmitter I26 in the pressure control device can be matched with the PLC I27, the master controller 101 controls the output pressure of the liquid nitrogen booster pump 15 through the PLC I27, and the pressure transmitter IV 62 is matched with the audible and visual alarm II 63; taking the safety valve II 25 as an example, when the detected pressure is greater than the maximum allowable pressure, the safety valve II 25 is used for safely releasing pressure, the pressure gauge V30 is used for detecting the passing liquid nitrogen pressure, and when the pressure does not reach the preset pressure, the PLC controller I27 is used for controlling the pressure of the liquid nitrogen booster pump 15.
Further, a pressure gauge I9, a low-temperature long-axis stop valve I10, a filter 11, a pressure gauge II 12 and a safety valve I13 are sequentially arranged on the liquid nitrogen conveying pipeline 19 from the liquid ammonia tank car to the booster pump; a one-way valve I22, a pressure gauge IV 23, a low-temperature long-shaft stop valve III 24, a pressure transmitter I26, a pressure gauge V30 and a temperature gauge I31 are sequentially arranged on the liquid nitrogen pressurizing pipeline 28 from the liquid nitrogen booster pump 15 to the air gasifier I32, and a low-temperature electric valve I29 is positioned between the pressure transmitter I26 and the pressure gauge V30;
the nitrogen conveying pipeline 42 is sequentially provided with a thermometer II 33, a pressure gauge VI 34, a temperature transmitter I35, a safety valve III 37, a low Wen Duanzhou stop valve I38, a pressure regulating valve I39, a pressure transmitter III 40 and a one-way valve II 47 from the air temperature gasifier I32 to the mixing proportioning mechanism 4, the temperature transmitter I35 is positioned between the thermometer II 33 and the safety valve III 37, the pneumatic regulating valve I43 and the turbine flowmeter I46 are positioned between the pressure transmitter III 40 and the one-way valve II 47, and the pressure transmitter III 40 is matched with an audible-visual alarm I41;
the liquid conveying pipeline 69 is provided with a low-temperature long-shaft stop valve IV 50, and the gaseous conveying pipeline 70 is provided with a thermometer IV 56, a pressure gauge VIII 57, a safety valve IV 59, a low Wen Duanzhou stop valve II 60, a pressure regulating valve II 61, a pressure transmitter IV 62 and a one-way valve III 66 from the air-temperature gasifier II 54 to the mixing and proportioning mechanism 4;
The temperature transmitter II 58 is positioned between the pressure gauge VIII 57 and the safety valve IV 59, the pneumatic regulating valve II 64 is positioned between the pressure transmitter IV 62 and the one-way valve III 66 where the turbine flowmeter II 65 is positioned, and the sound-light alarm II 63 is matched at the position of the pressure transmitter IV 62;
a butterfly valve 75 is arranged on the composite gas conveying pipeline 77;
specifically, the nitrogen conveying mechanism 2 and the carbon dioxide conveying mechanism 3 can be singly or jointly conveyed according to the actual conditions on site, and the maximum inert gas injection quantity reaches 2000m 3 And/h, the control requirements of natural ignition of coals of different scales are met, and the composite inert gas can be rapidly injected into each position through the pressure control device, so that the fire extinguishing effect is improved.
As shown in fig. 1, further, the liquid nitrogen booster pump 15 is connected to the liquid nitrogen tank car 7 through a nitrogen return pipeline 20;
a low-temperature long-shaft stop valve II 17 and a pressure gauge III 18 are arranged on the nitrogen return pipeline 20 from the liquid nitrogen booster pump 15 to the liquid nitrogen tank car 7;
specifically, the liquid nitrogen flowing in from the liquid nitrogen conveying pipeline 19 is partially gasified in the liquid nitrogen booster pump 15, and the generated nitrogen sequentially enters a nitrogen return port on the storage tank of the liquid nitrogen tank wagon 7 through the metal hose III 16 and the nitrogen return pipeline 20, so that the pressure balance between the storage tank of the liquid nitrogen tank wagon 7 and the liquid nitrogen booster pump 15 is completed.
As shown in fig. 2 and 3, further, the system is positioned in a bottom pry box 5 of the mobile car body;
the upper part of the bottom pry box body 5 is provided with a plurality of convection air fans which are correspondingly positioned above the nitrogen conveying mechanism 2 and the carbon dioxide conveying mechanism 3;
specifically, the mobile car body can ensure that the system moves to the vicinity of fire extinguishment and is matched with the liquid nitrogen tank car 7 and the liquid carbon dioxide tank car 48;
the convection exhaust fan 6 arranged above the bottom prying box body 5 can enhance the gasification efficiency of liquid nitrogen and liquid carbon dioxide, and the cold energy emission in the gasification process can cool down the underground operation environment, so that the efficient fire extinguishment of mines under different working conditions is realized, and meanwhile, the cold energy utilization is also realized;
when the low-temperature composite inert gas fire extinguishing system is used, the method specifically comprises the following steps:
s1: determining the mixing ratio of the composite inert gas
Sampling in the goaf in advance, and extracting a plurality of coal samples;
a1. placing the extracted coal sample in a coal sample experimental tank 86, opening an oxygen gas cylinder 78 and a nitrogen gas cylinder 79, adjusting an oxygen gas flow meter 88 and a nitrogen gas flow meter 89 to ensure that the mixing proportion accords with the nitrogen-oxygen proportion in the air, and uniformly mixing the two gases through a static mixer 84;
a2. the electric heater 93 is turned on, the real-time heating temperature is set to be 500 ℃, the air mixture obtained in the a1 is led into the coal sample experimental tank 86 at normal temperature through the filter screen 95, the gas reacted with the coal sample is filtered through the filter asbestos 91, the gas product change is monitored in real time through the gas analyzer 87, the temperature change of the coal sample at different positions is monitored in real time through the thermocouple 92, and the data are recorded in real time through the acquisition device 94;
a3. After the electric heater 93 is heated for a period of time, the oxygen gas bottle 78 is closed, the electric heater 93 is closed, the carbon dioxide gas bottle 80 is opened, the carbon dioxide flowmeter 90 and the nitrogen flowmeter 89 are regulated to enable the mixing proportion of the carbon dioxide gas bottle and the nitrogen flowmeter to be the first set of experimental proportion set in experiments, the cooling device 85 is opened, the temperature of the mixed gas entering the coal sample experimental tank 86 is ensured to be-30 ℃, and the temperature change of the coal sample and the change condition of gas products are monitored in real time until the temperature is reduced to be below 0 ℃;
a4. changing a new coal sample, changing the mixing proportion of carbon dioxide and nitrogen in the step a3, and repeating the operations of a1, a2 and a 3;
a5. according to parameters such as the coal temperature reduction rate of the coal sample under different carbon dioxide and nitrogen ratios, the concentration reduction rate of carbon monoxide/methane/ethylene index gas generated by spontaneous combustion and the like, selecting the carbon dioxide and nitrogen ratio with the fastest coal temperature and index gas concentration reduction rate as the final composite inert gas mixing ratio;
s2: liquid nitrogen gasification control method
When a local fire disaster happens in underground coal mine, the low-temperature composite inert gas fire extinguishing system is transported to the vicinity of the local fire disaster through an underground transportation rail or a mobile vehicle body, and the liquid nitrogen tank car 7 and the liquid carbon dioxide tank car 48 are reasonably regulated according to the actual fire disaster situation in the field;
a. The liquid nitrogen is conveyed from a liquid nitrogen inlet to a liquid nitrogen booster pump 15 from a liquid nitrogen tank car 7 along a liquid nitrogen conveying pipeline 19 to finish liquid nitrogen supply, the pressure of the liquid nitrogen supply is 0.1-0.2 MPa, and the temperature is-196 ℃;
meanwhile, the pressure gauge I9 is used for detecting the pressure of liquid nitrogen passing through the pressure inlet, the filter 11 is used for filtering liquid nitrogen impurities, the pressure gauge II 12 is used for detecting the pressure of liquid nitrogen passing through the filter 11, and the safety valve I13 is used for safely relieving pressure when the detected pressure is greater than the maximum allowable pressure;
b. after the pressurized liquid nitrogen flows out from the liquid nitrogen booster pump 15, the pressurized liquid nitrogen is conveyed into the air temperature gasifier I32 through the liquid nitrogen booster pump 15 and the liquid nitrogen booster pipeline 28, so that the pressurized liquid nitrogen is pressurized, and the pressure of the pressurized liquid nitrogen is 1.5MPa;
meanwhile, the pressure gauge IV 23 is used for detecting the pressure of liquid nitrogen passing through the liquid nitrogen booster pump 15, when the detected pressure is greater than the maximum allowable pressure, the safety valve II 25 is used for carrying out safety pressure relief, the pressure gauge V30 is used for detecting the pressure of liquid nitrogen passing through the low-temperature electric valve I29, and the temperature gauge I31 is used for detecting the temperature of liquid nitrogen passing through the low-temperature electric valve I29; the pressure transmitter I26 is used for converting the detected liquid nitrogen pressure into an analog signal and transmitting the analog signal to the PLC I27, and when the pressure does not reach the preset pressure, the PLC I27 performs pressure control on the liquid nitrogen booster pump 15;
c. The liquid nitrogen flowing in from the liquid nitrogen conveying pipeline 19 is partially gasified in the liquid nitrogen booster pump 15, and generated nitrogen sequentially enters a nitrogen return port on the storage tank of the liquid nitrogen tank wagon 7 through the metal hose III 16 and the nitrogen return pipeline 20, so that the pressure balance between the storage tank of the liquid nitrogen tank wagon 7 and the liquid nitrogen booster pump 15 is completed;
meanwhile, the pressure gauge III 18 is used for detecting the liquid nitrogen pressure of the nitrogen return pipeline 20;
d. the liquid nitrogen is gasified by an air gasifier I32 at equal pressure;
meanwhile, the temperature transmitter I35 and the PLC II 36 regulate and control the gasification liquid inlet amount of the liquid nitrogen by regulating the opening of the low-temperature electric valve I29, so that the temperature of the gasified liquid nitrogen is controlled to be-40 to-50 ℃;
e. the gasified nitrogen passes through a nitrogen conveying pipeline 42 to a pneumatic regulating valve I43, and the pressure of the nitrogen regulated by the pneumatic regulating valve I43 is 0.5MPa;
meanwhile, the thermometer II 33 is used for detecting the temperature of nitrogen passing through the air-temperature gasifier I32, the pressure gauge VI 34 is used for detecting the pressure of the nitrogen passing through the air-temperature gasifier I32, and the safety valve III 37 is used for carrying out safety pressure relief when the detected pressure is greater than the maximum allowable pressure; the pressure transmitter III 40 is used for converting the detected nitrogen pressure into an analog signal and transmitting the analog signal to the audible and visual alarm I41, and when the pressure exceeds the preset pressure, the audible and visual alarm I41 can give out audible and visual alarm;
S3: liquid carbon dioxide gasification control method
a. Liquid carbon dioxide is conveyed from the liquid carbon dioxide tank wagon 48 to the air temperature gasifier II 54 from the liquid carbon dioxide inlet to the downstream along a liquid conveying pipeline 69 to complete isobaric gasification;
meanwhile, the pressure gauge VII 52 is used for detecting the pressure of the liquid carbon dioxide passing through the low-temperature electric valve II 51, and the temperature gauge III 53 is used for detecting the temperature of the liquid carbon dioxide passing through the low-temperature electric valve II 51; the temperature transmitter II 58 is used for converting the detected carbon dioxide temperature into an analog signal and transmitting the analog signal to the PLC IV 55, and when the temperature does not reach the preset temperature, the PLC IV 55 performs temperature control on the low-temperature electric valve II 51;
b. the gasified carbon dioxide gas is conveyed to a pressure regulating valve II 61 through a gas conveying pipeline 70, and the pressure of the carbon dioxide gas regulated by the pressure regulating valve II 61 is 0.5MPa;
meanwhile, the thermometer IV 56 is used for detecting the temperature of carbon dioxide passing through the air-temperature gasifier II 54, the pressure meter VIII 57 is used for detecting the pressure of the carbon dioxide passing through the air-temperature gasifier II 54, and when the detected pressure is greater than the maximum allowable pressure, the safety valve IV 59 is used for safely releasing pressure;
s4: low-temperature composite inert gas proportioning control method
a. Inputting the final composite inert gas mixing proportion into a control system 1, controlling the flow of nitrogen entering a turbine flowmeter I46 by a flow transmitter I45 and a PLC controller III 44 through adjusting a pneumatic adjusting valve I43, controlling the flow of carbon dioxide entering a turbine flowmeter II 65 by a flow transmitter II 67 and a PLC controller V68 through adjusting a pneumatic adjusting valve II 64, and collecting the instantaneous flow proportion and the accumulated flow proportion in real time;
b. the nitrogen passing through the check valve II 47 and the carbon dioxide passing through the check valve III 66 are uniformly mixed in the gas mixer 71, namely, the nitrogen enters the premixing tube 107 of the venturi tube section 104 from the nitrogen gas inlet 102, the carbon dioxide enters the diffusion cavity 105 from the carbon dioxide gas inlet 103, and enters the premixing tube 107 through the swirl tube to be premixed with the nitrogen therein, the premixed gas enters the transition mixing section again, is transitionally mixed through a plurality of swirl plates 110, finally enters the full mixing section, is fully mixed through the baffle plate 111 and is discharged from the mixed gas outlet 112 and the composite gas conveying pipeline 77;
a temperature transmitter III 74 and a PLC controller VI 73 at the downstream of the gas mixer 71 monitor the temperature of the low-temperature composite inert gas in real time;
Meanwhile, if the temperature of the composite inert gas is higher than the set outlet temperature, the temperature transmitter II 58 and the PLC VI 73 act on the low-temperature electric valve I29 to increase the gasification amount of liquid nitrogen, and a temperature cascade control device is formed by the temperature transmitter II and the PLC VI 73 and the temperature control of the nitrogen gasification process.
c. The low-temperature composite inert gas is conveyed to the ignition area by a pipeline.
The low-temperature composite inert gas fire extinguishing system has good application expansibility, can be applied to underground coal mine fire extinguishment and ground fire-fighting areas, can be used by only moving the system to the vicinity of the ground fire-fighting areas to be matched with liquid nitrogen and liquid carbon dioxide tank cars 48, expands the application range and market potential of the system, and can also provide effective fire extinguishing solutions for other industries.
In the description of the present invention, it should be understood that the terms "center," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in the drawings, merely to facilitate describing the present invention and simplify the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.
Claims (8)
1. The application method of the low-temperature composite inert gas fire extinguishing system is characterized in that the fire extinguishing system adopted by the method comprises the following steps:
the nitrogen conveying mechanism (2) is connected between the liquid nitrogen tank car (7) and the mixing and proportioning mechanism (4) and is used for converting liquid nitrogen into nitrogen and conveying the nitrogen into the mixing and proportioning mechanism (4) through a nitrogen conveying pipeline (42);
the carbon dioxide conveying mechanism (3) is connected between the liquid carbon dioxide tank car (48) and the mixing and proportioning mechanism (4) and is used for converting the liquid carbon dioxide into a gas state and conveying the gas state into the mixing and proportioning mechanism (4) through a gas conveying pipeline (70);
the mixing proportioning mechanism (4) comprises a gas mixer (71), wherein the gas mixer (71) is provided with a venturi section (104), a diffusion cavity (105) connected with a carbon dioxide gas inlet (103) and a mixing pipe; a drainage tube (106) at the end part of the venturi tube section (104) is connected with a nitrogen gas inlet (102), the outer side of a premixing tube (107) at the middle part is wrapped by a diffusion cavity (105) and communicated with each other through a plurality of cyclone tube groups (109), and a release tube (108) at the other end part is connected with the mixing tube;
each swirl tube group (109) comprises a plurality of arc-shaped tubes which are circumferentially arranged in the same direction, and needles with opposite arc-shaped directions between adjacent swirl tube groups (109) are sequentially arranged; a plurality of cyclone plates (110) which are arranged at intervals are arranged in the mixing pipe and close to the venturi section (104), and an S-shaped multi-layer baffle plate (111) is arranged at a position far away from the venturi section (104) and is output and connected with a composite gas conveying pipeline (77);
The control system (1) is provided with a master controller (101), and the master controller (101) is connected with the nitrogen conveying mechanism (2) and the carbon dioxide conveying mechanism (3) and is used for controlling the flow, the pressure and the temperature of the conveying of corresponding media;
the method specifically comprises the following steps:
s1: determining the mixing ratio of the composite inert gas
Extracting and sampling coal in the goaf;
a1. placing the extracted coal sample in a coal sample experiment tank (86), opening an oxygen gas cylinder (78) and a nitrogen gas cylinder (79), adjusting an oxygen flow meter (88) and a nitrogen flow meter (89) to ensure that the mixing proportion is consistent with the nitrogen-oxygen proportion of the actual environment of the goaf, and uniformly mixing the two gases through a static mixer (84);
a2. the electric heater (93) is turned on, the real-time heating temperature is set, the air mixture obtained by the configuration of a1 is introduced into the coal sample experimental tank (86) at normal temperature through the filter screen (95), the gas reacted with the coal sample is filtered through the filter asbestos (91), the gas product change is monitored in real time through the gas analyzer (87), the temperature change of the coal sample at different positions is monitored in real time through the thermocouple (92), and the data is recorded in real time through the acquisition device (94);
a3. after the electric heater (93) is heated for a period of time, the oxygen gas cylinder (78) and the electric heater (93) are closed, the carbon dioxide gas cylinder (80) is opened, the carbon dioxide flowmeter (90) and the nitrogen flowmeter (89) are regulated to enable the mixing proportion to be a first set of experimental proportion set by experiments, the cooling device (85) is opened, the mixed gas enters the coal sample experimental tank (86) at a low temperature, and the temperature change of the coal sample and the change condition of a gas product are monitored in real time until the temperature is reduced to be below 0 ℃;
a4. Changing a new coal sample, changing the mixing proportion of carbon dioxide and nitrogen in the step a3, and repeating the operations of a1, a2 and a 3;
a5. according to the coal temperature reduction rate of the coal sample under different carbon dioxide and nitrogen ratios and the carbon monoxide/methane/ethylene index gas concentration reduction rate parameter generated by spontaneous combustion, selecting the carbon dioxide and nitrogen ratio with the fastest coal temperature index gas concentration reduction rate as the final composite inert gas mixing ratio;
s2: liquid nitrogen gasification control method
The low-temperature composite inert gas fire extinguishing system is moved to the vicinity of a local fire disaster, and a liquid nitrogen tank car (7) and a liquid carbon dioxide tank car (48) are reasonably regulated according to the actual fire disaster condition of the site;
a. liquid nitrogen is conveyed from a liquid nitrogen inlet to a liquid nitrogen booster pump (15) along a liquid nitrogen conveying pipeline (19) from a liquid nitrogen tank car (7) to be supplied with liquid nitrogen;
b. after flowing out of the liquid nitrogen booster pump (15), the pressurized liquid nitrogen is conveyed into the air temperature gasifier I (32) through the liquid nitrogen booster pump (15) and the liquid nitrogen booster pipeline (28);
meanwhile, the pressure gauge IV (23) is used for detecting the pressure of the liquid nitrogen passing through the liquid nitrogen booster pump (15), and the temperature gauge I (31) is used for detecting the temperature of the passing liquid nitrogen; when the pressure does not reach the preset pressure, the master controller (101) controls the pressure of the liquid nitrogen booster pump (15), and when the detected pressure is greater than the maximum allowable pressure, the safety valve II (25) performs safety pressure relief;
c. The liquid nitrogen flowing in from the liquid nitrogen conveying pipeline (19) is partially gasified in the liquid nitrogen booster pump (15), and generated nitrogen sequentially enters a nitrogen return port on a storage tank of the liquid nitrogen tank car (7) through a nitrogen return pipeline (20) to finish pressure balance between the storage tank of the liquid nitrogen tank car (7) and the liquid nitrogen booster pump (15);
d. the liquid nitrogen is gasified by an air temperature gasifier I (32) at equal pressure;
the master controller (101) adjusts and controls the gasification liquid inlet amount of the liquid nitrogen by adjusting the opening of the low-temperature electric valve I (29), thereby controlling the temperature of the gasified liquid nitrogen;
e. the gasified nitrogen is delivered to a pneumatic regulating valve I (43) through a nitrogen delivery pipeline (42), and the pneumatic regulating valve I (43) regulates the nitrogen pressure;
the thermometer II (33) detects the temperature of nitrogen passing through the air temperature gasifier I (32), the pressure gauge VI (34) detects the pressure of the nitrogen passing through the air temperature gasifier I (32), and the safety valve III (37) performs safety pressure relief when the detected pressure is greater than the maximum allowable pressure;
s3: liquid carbon dioxide gasification control method
a. Liquid carbon dioxide is conveyed from a liquid carbon dioxide tank car (48) to an air temperature gasifier II (54) from a liquid carbon dioxide inlet to the downstream along a liquid conveying pipeline (69) to finish isobaric gasification;
b. The gasified carbon dioxide gas is conveyed to a pressure regulating valve II (61) through a gas conveying pipeline (70), and the pressure regulating valve II (61) regulates the pressure of the carbon dioxide gas;
meanwhile, a thermometer IV (56) detects the temperature of carbon dioxide passing through an air temperature gasifier II (54), a pressure meter VIII (57) detects the pressure of the carbon dioxide passing through the air temperature gasifier II (54), and a safety valve IV (59) performs safety pressure relief when the detected pressure is greater than the maximum allowable pressure;
s4: low-temperature composite inert gas proportioning control method
a. Inputting the final composite inert gas mixing proportion in the step S1 into a control system (1), controlling the flow of nitrogen by a master controller (101) through adjusting a pneumatic adjusting valve I (43), controlling the flow of carbon dioxide by adjusting a pneumatic adjusting valve II (64), and collecting the instantaneous flow proportion and the accumulated flow proportion in real time;
b. nitrogen enters a premixing tube (107) of a venturi tube section (104) from a nitrogen inlet (102), carbon dioxide enters a diffusion cavity (105) from a carbon dioxide inlet (103), and enters the premixing tube (107) through a cyclone tube to be premixed with the nitrogen therein, the premixed gas enters a transition mixing section and is subjected to transition mixing through a plurality of cyclone plates (110), finally enters a full mixing section and is discharged from a mixed gas outlet (112) and a composite gas conveying pipeline (77) after being fully mixed through a baffle plate (111);
The temperature transmitter III (74) monitors the temperature of the low-temperature composite inert gas in real time and feeds the temperature back to the master controller (101);
if the temperature of the composite inert gas is higher than the set outlet temperature, the master controller (101) controls the low-temperature electric valve I (29) to increase the gasification amount of liquid nitrogen and form temperature cascade control with the temperature of the nitrogen gasification process;
c. the low-temperature composite inert gas is conveyed to the ignition area by a pipeline.
2. The method of using a low temperature composite inert gas fire suppression system according to claim 1, further comprising a coal natural simulation mechanism;
the coal nature simulation mechanism comprises:
the tank body assembly is used for correspondingly mixing oxygen with nitrogen and carbon dioxide with nitrogen according to the proportion and conveying the mixture into the coal sample experimental tank (86) through the connection of the cooling device (85);
the coal sample experimental tank (86) is internally provided with an electric heater (93), the extracted coal sample, the upper part of which is connected with a gas analyzer (87), and the periphery of which is uniformly provided with a plurality of thermocouples (92) along the vertical direction, wherein the thermocouples (92) are used for measuring the temperature change of the coal sample at different positions and transmitting data to the acquisition device (94);
the gas analyzer (87), the collecting device (94), the tank assembly and the electric heater (93) are all connected with the master controller (101) and controlled.
3. The method of using a cryogenic composite inert gas fire suppression system according to claim 2, characterized in that the tank assembly has an oxygen cylinder (78), a nitrogen cylinder (79), a carbon dioxide cylinder (80) respectively connected to the input of a static mixer (84);
an oxygen pressure reducing valve (81) and an oxygen flow meter (88) are arranged between the oxygen gas cylinder (78) and the static mixer (84), a nitrogen pressure reducing valve (82) and a nitrogen flow meter (89) are arranged between the nitrogen gas cylinder (79) and the static mixer (84), and a carbon dioxide pressure reducing valve (83) and a carbon dioxide flow meter (90) are arranged between the carbon dioxide gas cylinder (80) and the static mixer (84);
the lower part of the coal sample experiment tank (86) is provided with a filter screen (95), and the upper part is provided with a filter asbestos (91).
4. The method for using the low-temperature composite inert gas fire extinguishing system according to claim 2, wherein the nitrogen conveying mechanism (2) is provided with a liquid nitrogen booster pump (15) and an air temperature gasifier I (32);
the output end of the liquid nitrogen tank car (7) is sequentially connected with a liquid nitrogen conveying pipeline (19), a liquid nitrogen booster pump (15), a liquid nitrogen booster pipeline (28) and the input end of an air temperature gasifier I (32), and the output end of the air temperature gasifier I (32) is connected with a nitrogen conveying pipeline (42);
The carbon dioxide conveying mechanism (3) is provided with an air temperature gasifier II (54);
the output end of the liquid carbon dioxide tank car (48) is sequentially connected with a liquid conveying pipeline (69) and the input end of the air temperature gasifier II (54), and the output end of the air temperature gasifier II (54) is connected with a gaseous conveying pipeline (70).
5. The method of using a low temperature composite inert gas fire extinguishing system according to claim 4, wherein the control system (1) further comprises a flow control device, a temperature control device, and a pressure control device;
the flow control device is provided with a pneumatic regulating valve I (43) and a turbine flowmeter I (46) which are arranged on a nitrogen conveying pipeline (42), and a pneumatic regulating valve II (64) and a turbine flowmeter II (65) which are arranged on a gas conveying pipeline (70), wherein the turbine flowmeter I (46) is matched with a flow transmitter I (45) and transmits flow data to a PLC controller III (44), and the turbine flowmeter II (65) is matched with a flow transmitter II (67) and transmits flow data to a PLC controller V (68); the master controller (101) correspondingly controls the opening of the pneumatic regulating valve I (43) and the pneumatic regulating valve II (64) through the PLC III (44) and the PLC V (68);
The temperature control device is provided with a low-temperature electric valve I (29) and a thermometer I (31) which are arranged on a liquid nitrogen pressurizing pipeline (28), a thermometer II (33) and a matched temperature transmitter I (35) which are arranged on a nitrogen conveying pipeline (42), a thermometer IV (56) and a matched temperature transmitter II (58) which are arranged on a gaseous conveying pipeline (70), and a temperature transmitter III (74) which is arranged on a composite gas conveying pipeline (77); the master controller (101) receives signals of the temperature transmitter I (35) and the temperature transmitter II (58), correspondingly controls the opening of the low-temperature electric valve I (29) and the opening of the low-temperature electric valve II (51) positioned on the liquid conveying pipeline (69) to form an adjusting inner ring of cascade control, and the master controller (101) receives signals of the temperature transmitter III (74) to control the opening of the low-temperature electric valve I (29) to form an adjusting outer ring of cascade control;
the pressure control device comprises a pressure gauge IV (23) arranged on a liquid nitrogen pressurizing pipeline (28) and a matched pressure transmitter I (26), a pressure gauge VI (34) arranged on a nitrogen conveying pipeline (42) and a matched pressure transmitter III (40), a pressure gauge VIII (57) arranged on a gaseous conveying pipeline (70) and a matched pressure transmitter IV (62); the master controller (101) receives signals of the pressure transmitter I (26), controls the safety valve II (25) on the liquid nitrogen booster pump (15) and the liquid nitrogen booster pipeline (28), receives signals of the pressure transmitter III (40), controls the safety valve III (37) on the nitrogen conveying pipeline (42), and receives signals of the pressure transmitter IV (62) and controls the safety valve IV (59) on the gas conveying pipeline (70).
6. The method for using the low-temperature composite inert gas fire extinguishing system according to claim 5, wherein a one-way valve I (22), a low-temperature long-axis stop valve III (24) and a pressure gauge V (30) are further arranged on the liquid nitrogen pressurizing pipeline (28) in sequence from the liquid nitrogen pressurizing pump (15) to the air temperature gasifier I (32);
a low Wen Duanzhou stop valve I (38), a pressure regulating valve I (39) and a one-way valve II (47) are sequentially arranged on the nitrogen conveying pipeline (42) from the air-temperature gasifier I (32) to the mixing and proportioning mechanism (4), and an audible and visual alarm I (41) is matched at the pressure transmitter III (40);
a low-temperature long-axis stop valve IV (50) is arranged on the liquid conveying pipeline (69), and a low Wen Duanzhou stop valve II (60), a pressure regulating valve II (61) and a one-way valve III (66) are arranged on the gaseous conveying pipeline (70) from the air-temperature gasifier II (54) to the mixing and proportioning mechanism (4); an audible and visual alarm II (63) is matched at the pressure transmitter IV (62).
7. The application method of the low-temperature composite inert gas fire extinguishing system according to claim 6 is characterized in that a pressure gauge I (9), a low-temperature long-axis stop valve I (10), a filter (11), a pressure gauge II (12) and a safety valve I (13) are sequentially arranged on a liquid nitrogen conveying pipeline (19) from a liquid ammonia tank car to a booster pump;
The upstream of the liquid nitrogen booster pump (15) is connected to the liquid nitrogen tank car (7) through a nitrogen return pipeline (20);
a low-temperature long-axis stop valve II (17) and a pressure gauge III (18) are arranged on a nitrogen return pipeline (20) from a liquid nitrogen booster pump (15) to a liquid nitrogen tank car (7).
8. A method of using a cryogenic composite inert gas fire suppression system according to any one of claims 1 to 7, characterized in that the fire suppression system is located in a skid box (5) of a mobile vehicle body;
the upper part of the bottom prying box body (5) is provided with a plurality of convection air fans which are correspondingly positioned above the nitrogen conveying mechanism (2) and the carbon dioxide conveying mechanism (3).
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