WO2020228227A1

WO2020228227A1 - Dry powder spraying system and fire engine

Info

Publication number: WO2020228227A1
Application number: PCT/CN2019/110090
Authority: WO
Inventors: 田志坚; 李前进; 徐小东; 王贞军
Original assignee: 徐工集团工程机械股份有限公司; 徐工消防安全装备有限公司
Priority date: 2019-05-13
Filing date: 2019-10-09
Publication date: 2020-11-19
Also published as: DE112019003462T5

Abstract

The present disclosure relates to a dry powder spraying system and a fire engine. The dry powder spraying system comprises: a dry powder fluidization tank; a pressurized gas supply, pressure-adjustably in communication with the dry powder fluidization tank; a dry powder spraying apparatus, in communication with the dry powder fluidization tank, and configured to spray fluidized dry powder airflow; and a blow-aiding apparatus, configured to guide blow-aiding airflow of a set pressure to the dry powder spraying apparatus so as to satisfy a set spraying pressure required by the dry powder spraying apparatus. Based on the described technical solution, the embodiments of the present disclosure at least solve the problem of insufficient blowing pressure of an aerial apparatus.

Description

Dry powder injection system and fire truck

Cross references to related applications

This application is based on the application whose CN application number is 201910392622.6 and the application date is May 13, 2019, and the application whose CN application number is 201920679368.3 and whose application date is May 13, 2019, and claim their priority. The disclosures of the two CN applications are hereby incorporated into this application as a whole.

Technical field

The present disclosure relates to the field of fire protection, in particular to a dry powder injection system and a fire truck.

Background technique

With the development of cities and the gathering of urban population, high-rise fire fighting, large-scale building fire fighting and petrochemical equipment fire fighting have been highly valued by the society. In order to protect the lives and property safety of the people, the elevated fire trucks targeted at such fire fighting scenes have been It has become more widely used. Elevating fire trucks refer to fire trucks equipped with raising and fire extinguishing devices that can perform ascending fire fighting or fire rescue. They mainly include: elevated platform fire trucks, elevated jet fire trucks, and ladder fire trucks.

In order to deal with complex fire situations, the elevating fire trucks in related technologies usually use dry powder fire extinguishing agent for fire extinguishing treatment. The typical spraying process includes the following steps: ① Decompress and supply gas to the high-pressure nitrogen storage bottle ② Make the fluidized tank Dry powder fluidization → ③Open the dry powder outlet valve → ④ Make the dry powder-nitrogen two-phase flow into the conveying pipeline → ⑤ Make the supply to the dry powder injector to spray out → ⑥ Inject into the place where fire is needed.

Summary of the invention

According to the inventor's research, it is found that for step ① of the above spraying process, a nitrogen storage bottle with a pressure value of not more than 1.5 MPa is usually used to supply nitrogen at a constant pressure in the fluidization tank to fluidize the dry powder. Based on this, the tank body of the fluidized tank is usually designed according to the working pressure of 1.6MPa. Such working pressure is sufficient for conventional dry powder fire trucks, because the conveying pipeline from the fluidized tank to the spraying device is short and there is basically no height difference, so that the overall pressure loss of the conveying pipeline is small. In addition, the length and direction of the transportation pipeline on the conventional dry powder fire truck have been determined before leaving the factory. Therefore, as long as the pressure in the fluidized tank meets the requirements, the dry powder reaching the spray device will have sufficient spray kinetic energy accordingly.

However, for a fire truck with a certain height difference (usually greater than 30 meters), the dry powder injection system has a long transportation pipeline, a large height difference, and complicated pipeline changes and direction changes. In addition, with the changes in the lifting state of the raised fire truck boom or ladder frame, the height difference of the transport pipeline of the dry powder injection system and the complexity of pipeline change and direction change also increase. Therefore, the elevating fire truck in the related art often has the problem of insufficient spraying ability due to insufficient blowing pressure of the dry powder injection system.

In view of the technical problem of lack of spraying ability caused by insufficient blowing pressure, if the pressure of the constant pressure nitrogen supplied to the fluidized tank is increased, the design value of the working pressure of the fluidized tank will be increased accordingly, and the fluidized tank The thickness of the body and the thickness of the pipe wall of the transportation pipeline have increased significantly, resulting in a substantial increase in the overall weight and cost of the dry powder injection system, which restricts the development of the current elevated fire truck to a higher fire fighting height.

For step ② of the above spraying process, experiments have shown that the filling ratio of the fire extinguishing agent has a significant impact on its spray characteristics. Dry powder fire extinguishing agents with different physical properties usually have a suitable filling ratio range corresponding to their own types: current When the filling ratio of the fire extinguishing agent in the chemical tank is below this range, the supply amount and strength of the dry powder fire extinguishing agent will be insufficient, and it will be difficult to achieve a qualified fire extinguishing effect; and when it is higher than this range, it will also be used accordingly. Insufficient storage of driving gas in the fluidized tank affects the transport of the extinguishing agent at the bottom of the fluidized tank, which prolongs the release process of the extinguishing agent, and the driving pressure is low in the middle and late stages of the release of the extinguishing agent, which is easy to cause powder spraying and weakness. The phenomenon of pulsating powder delivery.

In response to this, the dry powder injection system of fire trucks in the related art mostly uses visual observation to observe the filling level of the dry powder fluidized tank, and determine the filling ratio of the dry powder fluidized tank based on this. However, for dry powder powder with micron particle size, different dry powder model batches, different filling or storage methods will affect the occupied volume of dry powder in the fluidized tank, so the judgment method based on filling height cannot Accurately measuring the filling ratio of the dry powder, as a result, the spray characteristics of the dry powder-nitrogen two-phase flow provided by the dry powder injection system cannot achieve the optimal injection efficiency.

For step ⑤ of the above spraying process, based on the existing industry mark "GA39-2016 Fire Trucks, Fire Fighting Requirements and Test Methods", the effective spraying rate of the dry powder spraying device (that is, the dry powder spraying delivery rate) is the most important measure for evaluating the dry powder spraying system. Important indicators. The effective injection rate is defined as the quality change of the fluidized tank per unit time, and the detection methods for this index mostly use the initial and the termination states (the termination state mostly uses the pressure in the fluidized tank to decrease to 0.5MPa as the criterion) The weighing difference of the fluidized tank below is divided by the spray time counted by the stopwatch to obtain the average spray rate and use it as an evaluation index.

The inventor’s research found that the effectiveness of dry powder blowing and extinguishing lies in the content of the extinguishing agent. The direct judgment basis for determining whether it is necessary to continue spraying is the effective spray rate of dry powder (unit: kg/s), not the indirect evaluation index-the dry powder tank Depressurization state. Because even if the pressure of the dry powder tank is still high, if the sprayed dry powder content is small and the supply intensity is not sufficient, it is basically worthless to continue spraying, which wastes both powder and nitrogen. Therefore, the lack of accurate determination and control of the timing of jet shutdown is also a common drawback of the current fire trucks with dry powder fire extinguishing systems.

In view of this, the present disclosure proposes a dry powder injection system and a fire truck, which can solve the problem of insufficient blowing pressure of the dry powder fire extinguishing system of the elevated fire truck. The many technical effects that can be produced by the preferred technical solutions among the many technical solutions provided by the present invention are described in detail below.

In one aspect of the present disclosure, there is provided a dry powder injection system, including: a dry powder fluidization tank; a high-pressure gas source, which is connected to the dry powder fluidization tank with adjustable pressure; a dry powder injection device, which is connected to the dry powder fluidization tank. A tank configured to inject a flow of dry powder that has been fluidized; and a blowing assist device configured to guide the blowing assist flow at a set pressure to the dry powder injection device to meet the settings required by the dry powder injection device Injection pressure.

In some embodiments, the blowing-assisted device includes: a blowing-assisted pipeline, which is respectively communicated with the dry powder fluidization tank and the dry powder injection device through a communication pipeline, and is configured to mix the dry powder airflow and the auxiliary blowing Air flow, and make the mixed gas flow to the dry powder injection device.

In some embodiments, the blowing-assisted pipeline includes: a first pipeline connected to a communication pipeline on one side of the dry powder fluidization tank and configured to spray the dry powder airflow; and a second pipeline having An inlet section and an outlet section, the inlet section is configured to introduce the blowing-assisted airflow, the centerline of the outlet section and the centerline of the first pipeline are parallel to each other, and are configured to flow through the second The blowing-assisted airflow of the pipeline has the same flow direction as the dry powder airflow.

In some embodiments, the first pipeline is sleeved on the outer side of the outlet section, or the outlet section is sleeved on the outer side of the first pipeline; the first pipeline and the outlet section The one located on the outer side of the center has an opening configured to be introduced into the other located on the inner side of the first pipeline and the outlet section.

In some embodiments, the center line of the first pipeline is collinear with the center line of the outlet section.

In some embodiments, the outer one of the first pipeline and the outlet section has a reduced-diameter pipeline section, and the reduced-diameter pipeline section is connected to the communication pipeline on one side of the dry powder injection device to avoid The blowing-assisted airflow flows back from the first pipeline.

In some embodiments, the flow area of the reduced diameter pipeline section changes uniformly with the flow direction.

In some embodiments, the first pipeline is sleeved outside the outlet section, the first pipeline has a first reduced-diameter pipeline section that shrinks and expands, and the first reduced-diameter pipeline section is connected to the The connecting pipeline on one side of the dry powder injection device is connected, and the outlet of the outlet section is located in the contraction area of the first reducing pipeline section.

In some embodiments, the inlet diameter of the first reducing pipe section is D1, the throat diameter is D2, and the outlet diameter is D3, the length of the contraction area of the first reducing pipe section is L1, and the length of the expansion area The length is L2, the diameter of the second pipeline is d1, the length of the outlet section entering the first reduced-diameter pipeline section is L3, the length of the outlet section not entering the contraction area is L4, the D1, D2, D3, D4, d1, L1, L2, L3, L4 meet the following conditions: D3=(1.2～1.5)*D1; D2=(0.7～0.9)*D1; L1=(3～5)*D1 ; L2=(0.8～1.1)*D1; L3=(0.2～0.3)*L1; d1=(0.2～0.4)*D1; and L4=(6～10)*d1.

In some embodiments, the first pipeline is sleeved inside the outlet section, and the outlet section has a second reduced diameter pipeline section that is contracted. The second reduced diameter pipeline section is the same as the dry powder injection device. The connecting pipeline on the side is connected, and the outlet of the first pipeline is located in the contraction area of the second reducing pipeline section.

In some embodiments, the outlet diameter of the second reducing pipe section is D5, the inlet diameter is D6, the length of the second reducing pipe section is L5, and the diameter of the first pipe is D7, so The diameter of the second pipeline is d2, the length of the outlet of the first pipeline from the outlet of the second reducing pipeline section is L6, and the D5, D6, D7, d2, L5, and L6 meet the following conditions: D5=D7; D6=(1.4～1.8)*D5; L5=(3～5)*D5; d2=(0.3～0.55)*D5; and L6=(0.4～0.6)*L5.

In some embodiments, the blowing assist device further includes an electronically controlled pressure relief valve, which is arranged between the blowing assist pipeline and the high-pressure air source, and is configured to control the pressure of the assisted blowing airflow.

In some embodiments, the blowing assist device further includes: a pressure sensor configured to measure the actual injection pressure at the inlet of the dry powder injection device; the electronically controlled pressure reducing valve is configured to: according to the set injection pressure The difference between the actual injection pressure and the actual injection pressure adjusts the pressure of the assisted blowing airflow.

In some embodiments, the blowing assist device further includes: a length measuring sensor configured to measure the length of a part of the connecting pipeline between the dry powder fluidization tank and the dry powder injection device; and an angle measuring sensor, Is configured to measure the inclination angle of the part of the connected pipeline with respect to the horizontal plane; the electronically controlled pressure reducing valve is configured to: determine the pressure of the part of the connected pipeline according to the length value and the change value of the angle Loss, adjust the pressure of the assisted blowing airflow.

In some embodiments, the dry powder injection system further includes: a weighing sensor configured to measure the weight of the dry powder fluidization tank; an alarm device configured to send out warning information; an on-board controller, and the weighing The sensor is connected in communication and is configured to calculate the corresponding optimal filling weight of the dry powder fluidized tank according to the received external input of the dry powder fire extinguishing agent brand, so that the weight measured by the weighing sensor When the weight reaches the optimal filling weight, the alarm device is triggered to give an alarm.

In some embodiments, the dry powder injection system further includes: a dry powder inlet valve provided at a dry powder injection port of the dry powder fluidization tank, configured to control the flow of dry powder injected into the dry powder fluidization tank; The vehicle-mounted controller is in communication with the dry powder inlet valve, and is configured to control the dry powder inlet valve to stop the dry powder when the weight measured by the weighing sensor reaches the optimal filling quality Raises.

In some embodiments, the dry powder injection system further includes: a dry powder outlet valve, which is arranged on the communication pipeline between the dry powder fluidization tank and the dry powder injection device, and is configured to control the communication pipeline On and off; the on-board controller is in communication with the dry powder outlet valve, and is configured to: calculate the effective dry powder injection rate according to the real-time weight of the dry powder fluidized tank measured by the load cell, and calculate When the obtained effective injection rate of the dry powder is lower than the minimum allowable injection rate corresponding to the brand of the dry powder extinguishing agent, the dry powder outlet valve is controlled to disconnect the communication pipeline.

The present disclosure also provides a fire truck, including the dry powder injection system described in any one of the foregoing.

Therefore, based on the foregoing technical solutions, the embodiments of the present disclosure can achieve at least one of the following beneficial technical effects:

With the aid of blowing device, without changing the rated working pressure of the dry powder fluidization tank of the existing dry powder fire truck, it solves the problem of raising the fire truck, especially the dry powder injection system of the raising fire truck with a height difference of more than 30 meters and long-distance transportation. The problem of insufficient blowing pressure in the pipeline. For conventional dry powder fire trucks, with the aid of the blowing assist device provided in this application, it is possible to increase its own blowing pressure, realize joint fire extinguishing operations with elevated fire trucks, and better respond to complex fire fighting scenarios such as high-rise fire fighting. In addition, this application measures the pressure loss of the transport pipeline under different wall frame attitudes, or measures the input pressure of the dry powder injection device, so as to realize the automatic matching of the blowing-assisted airflow pressure, thereby ensuring the efficiency of the blowing-assisting device and improving the height of the fire truck Extinguishing ability.

Calculate the real-time filling ratio by weighing the dry powder fluidized tank, calculate the corresponding optimal filling weight according to the brand of the dry powder extinguishing agent, and remind the operator to realize the dry powder through the alarm device during the filling process of the dry powder extinguishing agent Optimal filling of extinguishing agent to ensure the fire extinguishing efficiency of dry powder extinguishing agent.

The dry powder fluidized tank is weighed to calculate the effective dry powder spray rate, and when the effective dry powder spray rate is insufficient, the spray of the dry powder fire extinguishing agent is actively closed, thereby improving the economic efficiency of using the dry powder fire extinguishing agent.

Description of the drawings

The drawings described here are used to provide a further understanding of the present disclosure, and constitute a part of the present application. The exemplary embodiments of the present disclosure and the description thereof are only used to explain the present disclosure, and do not constitute an improper limitation of the present disclosure. In the attached picture:

FIG. 1 is a schematic diagram of the composition structure of a dry powder injection system provided by an embodiment of the disclosure;

FIG. 2 is a schematic structural diagram of a blow-assisted pipeline in a dry powder injection system provided by an embodiment of the disclosure;

FIG. 3 is a schematic structural diagram of another blowing assist pipeline in the dry powder injection system provided by the embodiment of the disclosure;

In the picture:

1. Dry powder fluidized tank;

2. High pressure gas source;

3. Dry powder injection device;

4. Blow-assisted device, 41, blow-assisted pipeline, 411, first pipeline, 412, second pipeline, 412a, inlet section, 412b, outlet section, 413, opening, 414a, first flange, 414b, first Two flanges, 415, partition, 4151, vent, 42, electronically controlled pressure reducing valve;

5. Load cell;

51. Pressure sensor, 52, length measuring sensor, 53, angle measuring sensor

6. Vehicle-mounted controller, 61. Display console;

71. Dry powder inlet valve, 72. Dry powder outlet valve;

8. External powder supply valve.

Detailed ways

Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the exemplary embodiments is merely illustrative, and in no way serves as any limitation to the present disclosure and its application or use. The present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present disclosure thorough and complete, and to fully express the scope of the present disclosure to those skilled in the art. It should be noted that unless specifically stated otherwise, the relative arrangement of components and steps, material components, numerical expressions, and numerical values set forth in these embodiments should be interpreted as merely exemplary rather than limiting.

The "first", "second" and similar words used in the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different parts. Similar words such as "include" or "include" mean that the element before the word covers the elements listed after the word, and does not exclude the possibility of covering other elements. "Up", "Down", "Left", "Right", etc. are only used to indicate the relative position relationship. When the absolute position of the described object changes, the relative position relationship may also change accordingly.

In this disclosure, when it is described that a specific device is located between the first device and the second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to another device, the specific device may be directly connected to the other device without an intermediate device, or may not be directly connected to the other device but has an intermediate device.

All terms (including technical or scientific terms) used in the present disclosure have the same meaning as understood by those of ordinary skill in the art to which the present disclosure belongs, unless specifically defined otherwise. It should also be understood that terms such as those defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of related technologies, and should not be interpreted in idealized or extremely formalized meanings unless explicitly stated here. Define like this.

The technologies, methods, and equipment known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be regarded as part of the specification.

1 to 3, in some embodiments, the present disclosure provides a dry powder injection system, including: a dry powder fluidization tank 1; a high-pressure gas source 2, connected to the dry powder fluidization tank 1 in an adjustable pressure; dry powder The spraying device 3 is connected to the dry powder fluidization tank 1 and is used to spray the dry powder air flow after fluidization; and the blowing assist device 4 can guide the blowing assist air flow at a set pressure to the dry powder spraying device 3 to The set spray pressure required by the dry powder spray device 3 is met.

The dry powder fluidization tank 1 is used to generate a dry powder-driving gas two-phase flow fire extinguishing agent. In the process of generating the fire extinguishing agent, first add dry powder to the dry powder fluidization tank 1, then depressurize the high-pressure gas source 2 and supply air to the dry powder fluidization tank 1, and then drive the gas with appropriate pressure The dry powder will be fluidized in the dry powder fluidization tank 1 to form a dry powder fire extinguishing agent that can be blown.

The high-pressure gas source 2 can be supplied through a high-pressure gas tank, or through a high-pressure gas station. In order to achieve a better fire extinguishing effect, the gas type in the high-pressure gas source 2 can be selected from a chemically stable gas such as nitrogen, carbon dioxide, or inert gas. The dry powder injection device 3 is used to inject the dry powder fire extinguishing agent into the fire fighting site at a specific spray range and spray speed, and usually includes a dry powder gun, a dry powder gun, and the like.

According to the existing standards of related dry powder fire trucks, when the high-pressure gas source 2 supplies gas to the dry powder fluidized tank 1, the gas supply pressure is usually not greater than 1.5 MPa. Correspondingly, the tank body strength of the existing dry powder fluidization tank 1 is usually designed according to the working pressure of 1.6 MPa, which is greater than the maximum air supply pressure to ensure the safety of the equipment in the process of fluidizing the dry powder. Based on this, the dry powder injection system of the existing dry powder fire truck is mainly composed of the dry powder fluidization tank 1, the high-pressure gas source 2, the dry powder injection device 3, and a transportation pipeline.

However, for elevating fire trucks, especially for elevating fire trucks with a height drop of more than 30 meters, due to the huge height drop, coupled with the significant lengthening of the transportation pipeline and the complicated change of diameter and direction, the current situation Some air supply pressures of 1.5 MPa cannot meet the blowing pressure requirements of the dry powder injection device 3, which affects the spray characteristics of the dry powder injection device 3.

Based on this, the present application uses the blowing assist device 4, without changing the strength of the dry powder fluidization tank 1, the supply pressure of the high-pressure gas source 2, and the strength of the transport pipeline, and the introduction of assisted blowing airflow meets the requirements of dry powder injection The injection pressure required by the device 3.

In addition, when the model of the dry powder injection device 3 is changed, the required set injection pressure will change accordingly; and when the delivery pipeline is deployed and arranged differently during fire fighting operations, it will also This results in different pressure loss of the dry powder fire extinguishing agent during the transportation process. Therefore, the blowing assist device 4 can guide the blowing assist airflow of the set pressure to the set injection pressure required by the dry powder injection device 3, taking into account the pressure loss in the dry powder fire extinguishing agent transportation process. Dry powder injection device 3.

Further, the blowing assist device 4 includes: a blowing assist pipeline 41, which is respectively connected to the dry powder fluidization tank 1 and the dry powder injection device 3 through a communication pipeline, and can mix the dry powder airflow and the blowing assist airflow , And make the mixed gas flow to the dry powder injection device 3.

As a specific implementation of the blowing assist device 4, the blowing assist pipeline 41 is connected between the dry powder fluidization tank 1 and the dry powder injection device 3 through communicating pipes at both ends, and is arranged in the The communication pipeline between the auxiliary blowing pipeline 41 and the dry powder fluidization tank 1 is called "the communication pipeline on the side of the dry powder fluidization tank 1"; correspondingly, it is arranged between the auxiliary blowing pipeline 41 and the dry powder fluidization tank 1. The connecting pipeline between the spraying devices 3 is called "the connecting pipeline on the side of the dry powder spraying device 3".

In order to overcome the height difference of the raised fire truck and the pressure loss of the dry powder fire extinguishing agent in the transportation pipeline, the blow-assisted pipeline 41 is used to introduce a blow-assisted airflow, which should have a higher ratio The dry powder airflow provided by the connecting pipeline on one side of the dry powder fluidization tank 1 has a greater pressure, so that the mixed blowing-assisting airflow and the dry powder airflow meet the pressure requirements of the dry powder injection device 3.

For those skilled in the art, in the process of mixing two gas streams, especially when the gas pressure after mixing is required, it is necessary to avoid pressure loss during the gas stream mixing process as much as possible. In response to this, the blowing-assisting pipeline 41 includes: a first pipeline 411 connected to a communication pipeline on one side of the dry powder fluidization tank 1 for spraying the dry powder airflow; and a second pipeline 412, It has an inlet section 412a and an outlet section 412b. The inlet section 412a is used to introduce the blowing-assisted airflow. The center line of the outlet section 412b and the center line of the first pipeline 411 are parallel to each other and are used to flow through The blowing-assisted airflow of the second pipeline 412 has the same flow direction as the dry powder airflow.

Wherein, the inlet section 412a and the outlet section 412b are for the division of the second pipeline 412, and the division depends on whether the pipeline is used for intake or exhaust. The division between the inlet section 412a and the outlet section 412b does not require the angle between the two to be a right angle, nor does it require that there is no other intermediate pipe section between the two for transitional airflow.

The first pipeline 411 for spraying the dry powder airflow and the outlet section 412b of the second pipeline 412 for spraying the assisted airflow have the same airflow direction, which can avoid The pressure loss caused by the different directions of the two airflows preserves the kinetic energy of the assisted airflow to the greatest extent. The first pipeline 411 and the second pipeline 412 whose flow directions are collinear can be arranged in a parallel manner. In this case, the first pipeline 411 and the second pipeline 412 can be arranged in parallel. The common downstream is additionally provided with a mixing pipeline for receiving the dry powder airflow and the blowing-assisting airflow and making the two airflows fully mixed and then merged.

Of course, as shown in FIGS. 2 to 3, the first pipeline 411 and the second pipeline 412 can also be arranged in a sheathing manner. Specifically: the first pipeline 411 is sheathed The outer side of the outlet section 412b, or the outlet section 412b is sleeved on the outer side of the first pipeline 411; and the outer one of the first pipeline 411 and the outlet section 412b has an opening 413, It is introduced into the other of the first pipeline 411 and the outlet section 412b located inside.

When the first pipeline 411 and the second pipeline 412 are arranged in a sleeved relationship, in order to avoid dry powder deposition and pressure loss caused by the turning of the pipeline, it is used to spray the dry powder airflow. The first pipeline 411 should maintain the flow direction unchanged. Based on this, as shown in FIG. 2, the first pipeline 411 is introduced into the second pipeline 412 through the opening 413 opened in the tube wall, and the second pipeline 412 turns the direction The outlet section 412b is sleeved in the first pipeline 411, so as to keep the dry powder airflow from changing direction before and after mixing. As shown in FIG. 3, the second pipeline 412 is introduced into the first pipeline 411 through the opening 413 opened in the direction along the flow direction of the first pipeline 411, and then the blowing-assisted airflow passes through The angle between the outlet section 412b and the inlet section 412a turns and mixes with the dry powder airflow in a manner of surrounding the first pipeline 411 to ensure that the flow direction of the dry powder airflow does not change.

Further, in order to make the blowing-assisting airflow and the dry powder airflow evenly mixed, the centerline of the first pipeline 411 and the centerline of the outlet section 412b may be configured to be collinear.

Further, in order to avoid the backflow of the blowing-assisted air flow with higher pressure to the first pipeline 411, the outer one of the first pipeline 411 and the outlet section 412b has a reduced diameter pipeline section, The variable-diameter pipeline section is connected with the communication pipeline on one side of the dry powder injection device 3 to prevent the blowing-assisted airflow from returning from the first pipeline 411.

For those skilled in the art, based on the continuity equation, the velocity and pressure of the air flow in the pipe will be affected by the flow area in the pipe: without considering the frictional resistance, the increase in the flow area of the pipe will reduce the speed of the air flow. And the pressure increases. Therefore, the present application uses the variable diameter pipeline section to form a reasonable pressure change at the outlet of the blowing-assisted airflow by using the change in the flow area of the pipeline, so that the blowing-assisted airflow is kept facing the dry powder injection device 3 The flow direction of the flow, so as to prevent the blowing-assisted airflow from flowing back from the first pipe 411.

The variable-diameter pipeline section can form a change in the flow area through pipeline sections with different radii, but the direct communication of pipeline sections with different radii will generate a large number of convex areas, which will cause a large pressure loss. Therefore, further, the flow area of the variable diameter pipeline section changes uniformly with the flow direction. The uniformly changing diameter reducing pipeline section can not only reduce the pressure loss caused by the convex expansion of the pipeline, but also effectively reduce the mixing of the auxiliary blowing air flow and the dry powder air flow when flowing through the reducing diameter pipeline section. The increase of turbulence intensity reduces the energy dissipation of the mixed air flow in the subsequent transportation process.

Referring to FIG. 2, in some embodiments, the first pipeline 411 is sleeved outside the outlet section 412b, and the first pipeline 411 has a contracted-expanded first diameter reducing pipeline section. The pipeline section is connected with the communication pipeline on one side of the dry powder injection device 3, and the outlet of the outlet section 412b is located in the contraction area of the first reducing pipeline section. The first variable diameter pipeline section means that along the flow direction, the airflow first passes through a pipeline section with a gradually reduced flow area, and then passes through a pipeline section with a gradually expanded flow area.

When the first pipeline 411 is sleeved outside the outlet section 412b, the blowing-assisted airflow will be surrounded by the dry powder airflow as a central flow. At this time, a contraction-expansion type first reducing pipeline section is provided, And connect the first variable diameter pipeline section to the connecting pipeline on the side of the dry powder injection device 3, which can ensure that the mixed airflow and the dry powder airflow are conveyed to the dry powder injection device 3 The transportation process is uniform and smooth.

In addition, the outlet of the outlet section 412b is located in the contraction area of the first reducing pipe section, and the pressure difference formed by the first reducing pipe section is used to effectively avoid the blowing airflow at the center. Flow back to the inlet of the variable diameter pipeline section. Specifically, the positive pressure gradient caused by the constricted section of the first reducing pipe section can make the blowing airflow continue to flow to the lower pressure area, so as to avoid the backflow of the blowing airflow; After passing through the throat of the first reducing pipe section with the dry powder airflow, the two will be better mixed, and will be gradually increased by the negative pressure gradient caused by the expansion section in the first reducing pipe section to make the mixed The airflow reaches a pressure value corresponding to the sum of the set injection pressure of the dry powder injection device 3 and the subsequent pipeline pressure loss.

Further, in order to reduce the turbulence intensity of the dry powder airflow generated during the high-speed assisted blowing process of the assisted blowing airflow, and prevent the assisted blowing airflow from flowing back to the inlet of the first reducing pipe section, the first variable The radial pipeline section is further set as:

The inlet diameter of the first reducing pipe section is D1, the throat diameter is D2, and the outlet diameter is D3, the length of the contraction area of the first reducing pipe section is L1, and the length of the expansion area is L2. The diameter of the second pipeline 412 is d1, the length of the outlet section 412b entering the first reduced-diameter pipeline section is L3, the length of the outlet section 412b not entering the contraction area is L4, the D1, D2 , D3, D4, d1, L1, L2, L3, L4 meet the following conditions: D3=(1.2～1.5)*D1; D2=(0.7～0.9)*D1; L1=(3～5)*D1; L2= (0.8～1.1)*D1; L3=(0.2～0.3)*L1; d1=(0.2～0.4)*D1; and L4=(6～10)*d1.

It should be noted that the inlet diameter D1, the throat diameter D2, the outlet diameter D3 of the first variable diameter pipeline section, and the diameter d1 of the second pipeline 412 all refer to the inner diameter of the corresponding pipeline.

3, in some other embodiments, the first pipeline 411 is sleeved inside the outlet section 412b, and the outlet section 412b has a contracted second diameter reducing pipeline section, which is connected to the The connecting pipeline on one side of the dry powder injection device 3 is connected, and the outlet of the first pipeline 411 is located in the contraction area of the second reducing pipeline section.

As shown in Figure 3, when the first pipeline 411 is sleeved inside the outlet section 412b, the first flange 414a provided in the middle of the first pipeline 411 can be connected to the second pipeline 412. The second flanges 414b on the end surface of the opening 413 are connected and fixed to each other. The portion of the first pipeline 411 inserted into the outlet section 412b may be supported by the partition 415 in the outlet section 412b, thereby forming a ring shape between the second reducing pipeline section and the first pipeline 411 Blow-assisted air outlet for the gap. Further, by arranging a vent 4151 on the circumference of the partition 415, the blowing-assisted airflow enters from the inlet section 412a, passes through the vent 4151, and then is uniform along the tapered inner wall of the outlet section 412b. In order to achieve the blowing-assisting function of the assisted blowing airflow to the dry powder airflow.

In order to ensure the uniformity and smoothness of the mixed blowing-assisted airflow and the dry powder airflow conveying process, and to ensure that the blowing-assisted airflow does not return to the inlet of the reducing pipe section, the second reducing pipe section can be Further configuration is:

The outlet diameter of the second reducing pipe section is D5, the inlet diameter is D6, the length of the second reducing pipe section is L5, the diameter of the first pipe 411 is D7, and the second pipe The diameter of is d2, the length between the outlet of the first pipeline 411 and the outlet of the second reducing pipeline section is L6, and the D5, D6, D7, d2, L5, and L6 meet the following conditions: D5=D7; D6=(1.4～1.8)*D5; L5=(3～5)*D5; d2=(0.3～0.55)*D5; and L6=(0.4～0.6)*L5.

It should be noted that the outlet diameter D5 and the inlet diameter D6 of the above-mentioned second reducing pipeline section, the diameter D7 of the first pipeline 411, and the diameter d2 of the second pipeline, all refer to the corresponding pipeline the inside diameter of.

In some embodiments, in order to control the blowing-assisted airflow pressure, so that the pressures of the mixed blowing-assisted airflow and the dry powder airflow meet the injection pressure requirements of the dry powder injection device 3, The blowing device 4 may further include: an electronically controlled pressure reducing valve 42 arranged between the blowing assist pipeline 41 and the high-pressure air source 2 for controlling the pressure of the blowing assist airflow.

In some embodiments, as a way to adjust the blowing-assisted airflow pressure, the blowing-assisted device 4 may further include: a pressure sensor 51 for measuring the actual injection pressure at the inlet of the dry powder injection device 3. Correspondingly, the electronically controlled pressure reducing valve 42 may be configured to adjust the pressure of the assisted blowing airflow according to the difference between the set injection pressure and the actual injection pressure.

In this adjustment mode, the on-board controller 6 outputs an electrical signal according to the deviation between the measured value P1 of the pressure sensor 51 and the set injection pressure P2 of the dry powder injection device 3 to adjust the electronically controlled pressure reducing valve The opening of 42 is used to control the pressure P3 of the assisted blowing airflow so that P1≥P2, so as to realize that the blowing pressure of the dry powder airflow at the terminal of the transport pipeline on the side of the dry powder injection device 3 meets the set injection of the dry powder injection device 3 pressure.

In other embodiments, as another way of adjusting the pressure of the assisted blowing airflow, the assisted blowing device 4 may further include: a length measuring sensor 52 for measuring the dry powder fluidization tank 1 and the The length value of the part of the connecting pipeline between the dry powder injection device 3; and the angle sensor 53 for measuring the inclination angle of the part of the connecting pipeline with respect to the horizontal plane. Correspondingly, the electronically controlled pressure reducing valve 42 may be configured to adjust the pressure of the assisted blowing airflow according to the pressure loss of the partially connected pipeline determined by the length value and the change value of the angle. The part of the communication pipeline here may be a part of the communication pipeline from the dry powder fluidization tank to the dry powder injection device with a height difference, for example, a section of the communication pipeline located on the boom or ladder frame of a raised fire truck.

Correspondingly, in this adjustment mode, the on-board controller 6 is based on the transport pipeline state determined by the length measuring sensor 52 and the angle measuring sensor 53, based on the experience between pipeline state and pipeline pressure loss Formula, the pressure loss Pb of the transport pipeline is calculated in real time by the calculation module of the on-board controller 6, combined with the set injection pressure P2 of the dry powder injection device 3, and the electronically controlled pressure reducing valve is outputted by an electrical signal 42 Control the pressure of the assisted blowing airflow P3=(1.1-1.3)*(Pb+P2). Based on this, by pre-calibrating the linear relationship between the electrical signal output by the on-board calculator and the blow-assisted air pressure output by the electronically controlled pressure reducing valve 42, the pressure P3 of the blow-assisted air can be achieved. Automatic control.

In some embodiments, the dry powder injection system further includes: a weighing sensor 5 for measuring the weight of the dry powder fluidization tank 1; an alarm device for issuing warning information; a vehicle-mounted controller 6, which is connected to the station by communication. The weighing sensor 5 is configured to calculate the corresponding optimal filling weight of the dry powder fluidized tank 1 according to the received external input of the dry powder fire extinguishing agent brand, so that the weight sensor When the measured weight reaches the optimal filling weight, the alarm device is triggered to give an alarm.

After the pre-implemented cold spray test has determined the optimal filling ratios of different dry powder injection devices 3 for different specifications of dry powder fire extinguishing agents, the on-vehicle controller 6 can set the corresponding preferences for different specifications of dry powder fire extinguishing agents. Loading quality. Based on this, as long as the correct dry powder fire extinguishing agent brand is input, the on-board controller 6 can automatically call the corresponding preferred filling ratio and the corresponding allowable loading quality.

During the filling process of the dry powder fluidized tank 1, the weighing sensor 5 can accurately detect the real-time filling quality of the dry powder extinguishing agent in the dry powder fluidized tank 1, and feed it back to the vehicle controller in real time 6. The vehicle-mounted controller 6 can reflect the real-time filling quality on the display console 61 for reference by the operator. Of course, the operator can be further reminded through the alarm information of the alarm device. Based on this, even if the dry powder fire extinguishing agent model is changed in the subsequent dry powder filling operation, as long as the correct dry powder fire extinguishing agent brand is entered, the on-board controller 6 can ensure the operation through the display console 61 or the alarm device The personnel realize the optimal filling of different types of dry powder fire extinguishing agents, so that the dry powder injection device 3 can obtain better fire extinguishing efficiency.

In some embodiments, in order to realize automatic control of the dry powder filling process of the dry powder fluidization tank 1, the dry powder injection system further includes: a dry powder inlet valve 71, which is provided in the dry powder fluidization tank 1. The material port is used to control the dry powder flow rate to be filled into the dry powder fluidization tank 1; the vehicle-mounted controller 6 is communicatively connected to the dry powder inlet valve 71, and is further configured to: in the weighing sensor When the measured weight reaches the optimal filling quality, the dry powder inlet valve 71 stops the dry powder filling.

In some embodiments, the dry powder injection system further includes: a dry powder outlet valve 72, which is arranged on the communication pipeline between the dry powder fluidization tank 1 and the dry powder injection device 3, for controlling the communication pipe The on-board controller 6 is communicatively connected to the dry powder outlet valve 72, and is further configured to: measure the real-time weight of the dry powder fluidized tank 1 according to the weighing sensor 5 to calculate the effective dry powder injection rate , And when the calculated effective dry powder injection rate is lower than the minimum allowable injection rate corresponding to the brand of dry powder fire extinguishing agent, the dry powder outlet valve 72 is controlled to disconnect the communication pipeline.

The effective injection rate is the mass of dry powder injection per unit time (unit: kg/s), this index reflects the supply intensity of the fire extinguishing agent, and is an important performance index of the dry powder fire extinguishing system. In the actual evaluation, in order to facilitate the detection operation, the dry powder deposition in the dry powder conveying pipeline is often ignored, and the mass change per unit time of the dry powder tank is used as the dry powder spraying rate and the effective spraying rate.

The minimum allowable injection rate depends on the grade of the dry powder fire extinguishing agent, and is a threshold value of the effective injection rate set according to the fire extinguishing efficiency. That is, when the dry powder injection delivery rate is lower than the minimum allowable injection rate, the dry powder fire extinguishing agent is basically It will not have a valuable fire extinguishing effect, and will waste a lot of dry powder and blowing gas.

Different from the existing calculation method that relies on the pressure detection in the dry powder fluidization tank 1 and the average effective injection rate through the beginning and end states, through the cooperation of the dry powder outlet valve 72 and the weighing sensor 5, The vehicle-mounted controller 6 can calculate the effective injection rate of dry powder in real time, and when the calculated dry powder injection rate is lower than the minimum allowable injection rate, actively stop the dry powder outlet valve 72 from transporting the dry powder airflow, thereby Avoid the continuous spraying of the dry powder fire extinguishing agent in the low fire extinguishing value state at the end of spraying, and reduce the waste of dry powder and nitrogen.

The embodiments of the dry powder injection system of the present disclosure will be further described below in conjunction with the accompanying drawings:

As shown in Figure 1, it is a schematic diagram of the composition structure of the dry powder injection system provided by the embodiment of the present disclosure. The related dry powder injection device is composed of three main components: a dry powder fluidization tank 1, a high-pressure gas source 2 and a dry powder injection device 3. The embodiment of the present disclosure additionally draws a blowing-assisted airflow from the high-pressure air source 2 on its basis, and introduces the blowing-assisted airflow into the dry powder airflow from the communication pipeline between the dry powder fluidization tank 1 and the dry powder injection device 3 to Increase the pressure of the dry powder fire extinguishing agent entering the dry powder injection device.

As shown by the dotted line in Fig. 1, the electronically controlled pressure reducing valve 42, the pressure sensor 51, the length measuring sensor 52 and the angle measuring sensor 53 are respectively communicatively connected to the on-board controller 6, so that the on-board controller 6 can be electronically controlled to reduce pressure. The opening of the valve 42 accurately controls the pressure of the assisted blowing airflow. In addition, the load cell 5 and the display console 61 are respectively communicatively connected to the on-board controller 6, so that the on-board controller 6 can implement the real-time weight of the dry powder fluidized tank 1, so as to determine the dry powder filling quality and the dry powder fire extinguishing agent during the dry powder filling process. The effective spray rate of the dry powder in the spraying process is controlled, and the display console 61 is used to display and provide operation options to the operator.

Fig. 1 also shows an external powder supply valve 8 connected to the outlet of the blowing assist pipeline 41, its function is to send the mixed dry powder to the mixed dry powder when the effective injection rate of the mixed blowing assist airflow and the dry powder airflow does not meet the requirements Additional dry powder provided by the fire extinguishing agent. The external powder supply valve 8 can increase the effective injection rate of the dry powder without changing the existing dry powder injection system.

Figures 2 and 3 are respectively structural schematic diagrams of two blow-assisting pipelines in the dry powder injection system provided by the embodiments of the disclosure. Figure 2 shows that the first pipeline is sleeved outside the outlet section of the second pipeline. Figure 3 shows that the first pipeline is sleeved inside the outlet section of the second pipeline.

The embodiment of the present disclosure solves the problem of raising the fire truck, especially the high fire truck dry powder with the height difference greater than 30 meters, without changing the rated working pressure of the existing dry powder fluidization tank 1 of the dry powder fire truck. The problem of insufficient blowing pressure in the injection system or long-distance conveying pipeline. For conventional dry powder fire trucks, with the aid of the blowing assist device 4 provided in this application, it is possible to increase its own blowing pressure, realize joint fire fighting operations with elevated fire trucks, and better respond to complex fire fighting scenarios such as high-rise fire fighting;

In the embodiments of the present disclosure, by measuring the pressure loss of the conveying pipeline under different wall frame attitudes, or measuring the input pressure of the dry powder injection device 3, the automatic matching of the blowing-assisted air pressure is realized, thereby ensuring the efficiency of the blowing-assisting device 4 and improving the performance. High fire fighting capacity of fire trucks;

In the embodiment of the present disclosure, the dry powder fluidized tank 1 is weighed to calculate its real-time filling ratio, the corresponding optimal filling weight is calculated according to the brand of the dry powder extinguishing agent, and the alarm device is passed through the dry powder extinguishing agent during the filling process Remind the operator to realize the optimal filling of the dry powder fire extinguishing agent to ensure the fire extinguishing efficiency of the dry powder fire extinguishing agent;

In the embodiment of the present disclosure, the dry powder fluidized tank 1 is weighed to calculate the effective dry powder spray rate, and when the effective dry powder spray rate is insufficient, the spray of the dry powder fire extinguishing agent is actively shut down, thereby improving the economic efficiency of using the dry powder fire extinguishing agent.

So far, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concept of the present disclosure, some details known in the art are not described. Based on the above description, those skilled in the art can fully understand how to implement the technical solutions disclosed herein.

Although some specific embodiments of the present disclosure have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present disclosure. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

A dry powder injection system, including:

Dry powder fluidized tank;

A high-pressure gas source connected to the dry powder fluidization tank in an adjustable pressure manner;

A dry powder injection device, connected to the dry powder fluidization tank, configured to inject the fluidized dry powder airflow; and

The blowing assist device is configured to guide the blowing assist airflow at a set pressure to the dry powder injection device to meet the set injection pressure required by the dry powder injection device.
The dry powder injection system according to claim 1, wherein the blowing assist device comprises:

Blow-assisted pipelines are respectively communicated with the dry powder fluidization tank and the dry powder spraying device through communication pipelines, and are configured to mix the dry powder airflow and the blowing-assisted airflow, and spray the mixed gas toward the dry powder The device flows.
The dry powder injection system according to claim 2, wherein the auxiliary blowing pipeline comprises:

The first pipeline is connected to the communication pipeline on one side of the dry powder fluidization tank and is configured to spray the dry powder airflow; and

The second pipeline has an inlet section and an outlet section, the inlet section is configured to introduce the blowing-assisted airflow, the centerline of the outlet section and the centerline of the first pipeline are parallel to each other, and are configured to make The blowing-assisted airflow flowing through the second pipeline has the same flow direction as the dry powder airflow.
The dry powder injection system according to claim 3, wherein the first pipeline is sleeved outside the outlet section, or the outlet section is sleeved outside the first pipeline; the first One of the pipeline and the outlet section located on the outer side has an opening and is configured to be introduced into the other of the first pipeline and the outlet section located on the inner side.
The dry powder injection system according to claim 4, wherein the center line of the first pipeline is collinear with the center line of the outlet section.
The dry powder injection system according to claim 4, wherein the outer one of the first pipeline and the outlet section has a reduced diameter pipeline section, and the reduced diameter pipeline section is connected to one side of the dry powder injection device The connecting pipeline is connected to prevent the blowing-assisted airflow from flowing back from the first pipeline.
The dry powder injection system according to claim 6, wherein the flow area of the variable-diameter pipeline section changes uniformly with the flow direction.
The dry powder injection system according to claim 3, wherein the first pipeline is sleeved on the outside of the outlet section, the first pipeline has a first reduced-diameter pipeline section that shrinks and expands, and the first The diameter-reducing pipeline section is connected with the communication pipeline on one side of the dry powder injection device, and the outlet of the outlet section is located in the contraction area of the first diameter-reducing pipeline section.
The dry powder injection system according to claim 8, wherein the inlet diameter of the first reducing pipe section is D1, the throat diameter is D2, and the outlet diameter is D3, and the contraction area of the first reducing pipe section is The length is L1, the length of the expansion zone is L2, the diameter of the second pipeline is d1, the length of the outlet section entering the first reducing pipeline section is L3, and the outlet section does not enter the contraction zone The length of is L4, and the D1, D2, D3, D4, d1, L1, L2, L3, L4 meet the following conditions: D3=(1.2～1.5)*D1; D2=(0.7～0.9)*D1; L1= (3～5)*D1; L2=(0.8～1.1)*D1; L3=(0.2～0.3)*L1; d1=(0.2～0.4)*D1; and L4=(6～10)*d1.
The dry powder injection system according to claim 3, wherein the first pipeline is sleeved inside the outlet section, the outlet section has a second reduced diameter pipeline section that is contracted, and the second reduced diameter pipeline section It is connected with the communication pipeline on one side of the dry powder injection device, and the outlet of the first pipeline is located in the contraction area of the second reducing pipeline section.
The dry powder injection system according to claim 10, wherein the outlet diameter of the second reducing pipe section is D5, the inlet diameter is D6, the length of the second reducing pipe section is L5, and the first pipe The diameter of the pipeline is D7, the diameter of the second pipeline is d2, the length of the outlet of the first pipeline from the outlet of the second reducing pipeline section is L6, and the D5, D6, D7, d2, L5 and L6 meet the following conditions: D5=D7; D6=(1.4～1.8)*D5; L5=(3～5)*D5; d2=(0.3～0.55)*D5; and L6=(0.4～0.6)* L5.
The dry powder injection system according to claim 2, wherein the blowing assist device further comprises:

The electronically controlled pressure reducing valve is arranged between the blowing assist pipeline and the high-pressure air source, and is configured to control the pressure of the blowing assist airflow.
The dry powder injection system according to claim 12, wherein the blowing assist device further comprises:

A pressure sensor configured to measure the actual injection pressure at the inlet of the dry powder injection device;

The electronically controlled pressure reducing valve is configured to adjust the pressure of the assisted blowing airflow according to the difference between the set injection pressure and the actual injection pressure.
The dry powder injection system according to claim 12, wherein the blowing assist device further comprises:

A length measuring sensor configured to measure the length value of a part of the communication pipeline between the dry powder fluidization tank and the dry powder injection device; and

An angle measuring sensor configured to measure the inclination angle of the part of the communicating pipeline with respect to the horizontal plane;

The electronically controlled pressure reducing valve is configured to adjust the pressure of the assisted blowing airflow according to the pressure loss of the part of the connected pipeline determined by the length value and the change value of the angle.
The dry powder injection system according to claim 1, further comprising:

A load cell, configured to measure the weight of the dry powder fluidization tank;

Alarm device, configured to send out warning information;

The vehicle-mounted controller is communicatively connected with the load cell and is configured to calculate the corresponding optimal filling weight of the dry powder fluidized tank according to the received externally input dry powder extinguishing agent brand, so as to When the weight measured by the weighing sensor reaches the optimal filling weight, the alarm device is triggered to give an alarm.
The dry powder injection system according to claim 15, further comprising:

The dry powder inlet valve is arranged at the dry powder injection port of the dry powder fluidization tank, and is configured to control the dry powder flow rate that is filled into the dry powder fluidization tank;

The vehicle-mounted controller is in communication with the dry powder inlet valve, and is configured to control the dry powder inlet valve to stop the dry powder when the weight measured by the weighing sensor reaches the optimal filling quality Raises.
The dry powder injection system according to claim 15, further comprising:

The dry powder outlet valve is arranged on the communication pipeline between the dry powder fluidization tank and the dry powder injection device, and is configured to control the on and off of the communication pipeline;

The vehicle-mounted controller is communicatively connected to the dry powder outlet valve, and is configured to: calculate the effective dry powder injection rate according to the real-time weight of the dry powder fluidization tank measured by the load cell, and calculate the effective spray rate of the dry powder according to the calculated weight. When the effective injection rate of the dry powder is lower than the minimum allowable injection rate corresponding to the brand of the dry powder extinguishing agent, the dry powder outlet valve is controlled to disconnect the communication pipeline.
A fire truck, comprising the dry powder injection system according to any one of claims 1-17.