Gas detection device under negative-pressure medium-temperature gas-solid two-phase working condition and control method

Abstract

The invention discloses a gas detection device and a control method under a negative-pressure medium-temperature gas-solid two-phase working condition, the gas detection device comprises a gas inlet module, the gas inlet module comprises a gas inlet piece, the gas inlet port of the gas inlet piece can be used for filtering, the side walls of the two ends of the gas inlet piece are connected with a gas inlet pipeline and a gas outlet pipeline, and the gas inlet pipeline is communicated with the gas outlet pipeline through the gas inlet piece; the air inlet pipeline is provided with a cooler, a booster pump and a measuring device, the tail end of the exhaust pipeline is provided with an exhaust hole, the blowback module is connected with the air inlet module through a pipeline, the blowback module comprises a compressed air storage tank and a blowback valve assembly arranged on the pipeline, and air is introduced into the air inlet pipeline to form a plurality of groups of blowback lines; on-off control of the blowback valve assembly can guide to form different blowback lines, it is guaranteed that a negative pressure area in a pipeline is reduced, entering of impurities is reduced, working continuity and stability of the detection device are guaranteed, the service life of the detection device is prolonged, regular overhaul and maintenance difficulty and frequency are reduced, and losses of manpower and material resources are reduced.

Description

Technical Field

[0001] The present invention relates to the field of gas content detection in power stations, and in particular to a gas detection device and a control method under a negative pressure and medium temperature gas-solid two-phase working condition. Background Art

[0002] In the coal grinding and pulverizing system of an IGCC power station, gas content detection is a key link to ensure the safe operation of the system. In the prior art, a complete set of oxygen and carbon monoxide detection equipment is usually installed at the outlet of the pulverized coal filter to monitor the composition of the sampled gas under negative pressure, medium temperature, and containing a large amount of coal ash and water vapor. The typical working process of such detection equipment is as follows: after the sampled gas is filtered by the filter, it enters the condenser on the premise that the sampling solenoid valve is opened, and the condensed water is removed through the condenser. Then, under the action of the booster pump, the negative pressure is converted into positive pressure, and under the action of pressure, it enters the infrared measurement secondary meter for component detection. At the same time, a compressed air storage tank and multiple solenoid valves are equipped to purge the sampling pipeline to prevent coal ash and condensed water from blocking the pipeline and causing inaccurate measurement.

[0003] It is necessary to solve the deficiencies of the oxygen and carbon monoxide detection equipment, improve the safety factor of stable operation by transforming the pretreatment device, reduce the workload of maintenance and repair, and thus reduce the loss of human resources; the cost of the entire system equipment is relatively high, and the maintenance and repair are difficult. When the sampled gas pipeline is under negative pressure, some impurity gases will enter the pipeline, resulting in inaccurate measurement, and the pipeline is prone to blockage, affecting the accuracy of the measurement operation. Summary of the Invention

[0004] Therefore, the technical problems to be solved by the present invention are as follows: it is impossible to ensure the continuity and stability of the operation of the detection device, the service life of the detection device is relatively short, the difficulty and frequency of regular maintenance and repair are relatively high, and a large amount of human and material resources are consumed.

[0005] The above technical problems are solved by the following technical solutions: The present invention provides a gas detection device under a negative pressure and medium temperature gas-solid two-phase working condition, including an intake module, which includes an intake member. The intake port of the intake member can be filtered. The two side walls of the intake member are connected to an intake pipeline and an exhaust pipeline, and the intake pipeline is communicated with the exhaust pipeline through the intake member. A cooler, a booster pump, and a measuring device are arranged on the intake pipeline. An exhaust hole is arranged at the end of the exhaust pipeline. A backflush module is connected to the intake module through a pipeline, which includes a compressed air storage tank and a backflush valve assembly arranged on the pipeline. Gas is introduced into the intake pipeline to form several groups of backflush lines, and the on-off control of the backflush valve assembly can guide the formation of different backflush lines.

[0006] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The backflush valve assembly is connected to the pipeline, and it includes a first backflush valve, a second backflush valve, and a third backflush valve. The first backflush valve and the second backflush valve respectively connect an air storage tank and an intake pipeline through pipelines to form a backflush line. The third backflush valve is arranged on the intake pipeline and controls the switching between the first backflush valve pipeline and the second backflush valve pipeline.

[0007] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The cooler, booster pump, and measuring device on the intake pipeline are arranged in sequence. The first backflush valve acts on the intake filter, the second backflush valve acts in front of the cooler, the third backflush valve acts on the intake pipeline and controls the splitting of the first backflush valve pipeline and the second backflush valve pipeline, and the backflush module finally discharges from the exhaust hole.

[0008] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The intake pipeline arranges the booster pump, cooler, filter, sample gas flowmeter, and measuring device in sequence. The booster pump is connected to the intake pipeline through a booster pipeline.

[0009] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The backflush valve assembly further includes a fourth backflush valve and a fifth backflush valve. The fourth backflush valve is arranged on the intake pipeline and between the third backflush valve and the second backflush valve pipeline. One end of the booster pipeline is connected between the third backflush valve and the fourth backflush valve, and the fifth backflush valve is arranged in this section. The other end of the booster pipeline is connected between the fourth backflush valve and the second backflush valve pipeline.

[0010] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The intake module further includes a check valve assembly, a blowdown valve, and an exhaust valve. The check valve assembly includes a first check valve and a second check valve. The first check valve and the second check valve are respectively arranged on the two booster pipelines where the booster pump is located and control the cooperation between the booster pump and the intake pipeline.

[0011] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The blowdown valve controls the blowdown of the cooler, and the cooler further includes a compressed air pipeline.

[0012] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: The exhaust valve is arranged between the filter and the sample gas flowmeter to form a pressure relief pipeline.

[0013] The beneficial effects of the gas detection device under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention are as follows: it ensures that the negative pressure area in the pipeline is reduced, reduces the entry of impurities, ensures the continuity and stability of the operation of the detection device, extends the service life of the detection device, reduces the difficulty and frequency of regular maintenance, and saves the loss of human and material resources.

[0014] Another object of the present invention is to provide a control method for a gas detection device under the negative pressure medium-temperature gas-solid two-phase working condition, aiming to solve the problem that the detection device under the negative pressure medium-temperature gas-solid two-phase working condition cannot operate automatically, and during the purging process, the opening and closing of purging need to be manually controlled, resulting in unstable gas and impurity content inside the pipeline.

[0015] To solve the above technical problems, the present utility model also provides the following technical solution: a control method for a gas detection device under the negative pressure medium-temperature gas-solid two-phase working condition, which includes.

[0016] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: taking the opening of the third backflush valve and the fifth backflush valve and the closing of the fourth backflush valve, the first backflush valve, the second backflush valve, and the exhaust valve as the initial state, different backflush circuits are formed by controlling the valve switches through the PLC.

[0017] In a preferred embodiment of the gas detection device and control method under the negative pressure medium-temperature gas-solid two-phase working condition of the present invention: after timing by a timer, purging starts, the booster pump is stopped, the third backflush valve is closed, and the first backflush valve is opened for primary purging. Then, the first backflush valve is closed, the second backflush valve and the exhaust valve are opened for secondary purging. Then, the fifth backflush valve and the exhaust valve are closed, and the third backflush valve and the fourth backflush valve are opened for tertiary purging. Subsequently, the second backflush valve and the fourth backflush valve are closed, and the fifth backflush valve is opened to end the purging. At this time, the booster pump is started, and the purging timer starts timing again to form a cycle.

[0018] The beneficial effects of the present invention are as follows: under the negative pressure medium-temperature gas-solid two-phase working condition, the detection device can operate automatically, and during the purging process, the opening and closing of purging are automatically controlled, greatly reducing the instability of the gas and impurity content inside the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below only relate to some embodiments of the present invention and do not limit the present invention. Among them:

[0020] Figure 1 Shows an overall schematic diagram of the gas inlet and backflush circuits of the gas detection device under the negative pressure medium-temperature gas-solid two-phase working condition;

[0021] Figure 2 It shows an overall schematic diagram of the intake and backflush lines of the gas detection device with an added pressurization pipeline under the negative pressure medium-temperature gas-solid two-phase working condition;

[0022] Figure 3 It shows an overall flow chart of the control method;

[0023] Figure 4 It shows the PLC control diagram of the control method. Specific embodiments

[0024] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below in conjunction with specific embodiments and the accompanying drawings.

[0025] The terms used in the present invention are those general terms currently widely used in the art in consideration of the functions of the present invention, but these terms may vary according to the intentions of those of ordinary skill in the art, precedents, or new technologies in the art. In addition, specific terms may be selected by the applicant, and in this case, their detailed meanings will be described in the detailed description of the present invention. Therefore, the terms used in the specification should not be understood as simple names, but based on the meanings of the terms and the overall description of the present invention.

[0026] Referring to Figures 1 to 4 , this embodiment provides a gas detection device and a control method under the negative pressure medium-temperature gas-solid two-phase working condition. The intake module 1 includes an intake member 11. The intake port of the intake member 11 can be filtered. The two side walls of the intake member 11 are connected to an intake pipeline and an exhaust pipeline, and the intake pipeline is communicated with the exhaust pipeline through the intake member 11. A cooler 12, a booster pump 13, and a measuring device 14 are arranged on the intake pipeline. An exhaust hole 15 is arranged at the end of the exhaust pipeline. The backflush module 2 cooperates with the intake module 1 to form several groups of backflush lines. It includes a compressed air storage tank 21 and a backflush valve assembly V. The backflush valve assembly V controls the switching to guide the formation of backflush lines. The intake pipeline arranges the cooler 12, the booster pump 13, and the measuring device 14 in sequence. The backflush valve assembly V includes a first backflush valve V1, a second backflush valve V2, and a third backflush valve V3. The first backflush valve V1 and the second backflush valve V2 form a backflush line acting on the intake pipeline. The third backflush valve V3 is arranged on the intake pipeline to control the pipelines of the first backflush valve V1 and the second backflush valve V2. The first backflush valve V1 acts on the intake member 11, the second backflush valve V2 acts in front of the cooler 12, and the third backflush valve V3 acts on the intake pipeline to control the splitting of the pipelines of the first backflush valve V1 and the second backflush valve V2. The backflush module 2 finally discharges from the exhaust hole 15.

[0027] As shown in the attached Figure 1As shown, first, the air is compressed by the compressed air storage tank 21. Then, the first backflush valve V1 is opened and the third backflush valve V3 is closed, so that the compressed gas purges the filter port 11. This part of the gas finally discharges from the exhaust hole 15, and the gas passing through the second backflush valve V2 purges the gas from the cooler 12 of the intake pipeline to the front of the booster pump 13.

[0028] As shown in the Figure 2 attachment, further, the intake module 1 includes an intake part 11. Subsequently, the intake pipeline and the exhaust pipeline are respectively formed. The intake direction includes the cooler 12, the booster pump 13, and the measuring device 14. The cooler 12 adopts swirl cooling. The swirl cooler increases the contact area and contact time between the sample gas and the cooling wall surface by making the sample gas generate swirl inside the cooler 12, thereby improving the cooling efficiency. When dealing with high-temperature sample gas containing a large amount of water vapor, the cooling effect is remarkable, and it will not cause the sample gas temperature to be too high, nor will it affect the accuracy of subsequent detection. The booster pump 13 adopts a piston-type booster pump. The mechanical structure of the piston-type booster pump 13 is more robust, with high operating stability and long service life, reducing the measurement interruption caused by equipment failure.

[0029] The exhaust gas pipeline includes an exhaust hole 15 and a backflush module 2, which forms several groups of backflush circuits in cooperation with the intake module 1. The backflush module 2 includes a compressed air storage tank 21 and a backflush valve assembly V. The on-off control between the backflush valve assemblies V guides the formation of backflush circuits. The intake pipeline arranges the cooler 12, the booster pump 13, and the measuring device 14 in sequence. The backflush valve assembly V includes a first backflush valve V1, a second backflush valve V2, and a third backflush valve V3. The intake pipeline arranges the booster pump 13, the cooler 12, the filter 16, the sample gas flowmeter 17, and the measuring device 14 in sequence. The filter 16 is a visual filter, which is installed in the sample gas treatment process to filter residual solid particles in the sample gas, such as coal ash, dust, etc. If these particles enter downstream detection instruments or other precision equipment, it may cause equipment blockage, wear, or inaccurate measurement. Moreover, the visual filter 16 is more convenient for disassembly and replacement, so as to maintain a relatively high filtration efficiency of the filter 16. The booster pump 13 is connected to the intake pipeline through a booster pipeline. The backflush valve assembly V also includes a fourth backflush valve V4 and a fifth backflush valve V5. The fourth backflush valve V4 is arranged on the intake pipeline and between the pipelines of the third backflush valve V3 and the second backflush valve V2. One end of the booster pipeline is connected between the third backflush valve V3 and the fourth backflush valve V4, and the fifth backflush valve V5 is arranged in this section. The other end of the booster pipeline is connected between the pipelines of the fourth backflush valve V4 and the second backflush valve V2. The intake module 1 also includes a one-way valve assembly H, a drain valve D, and an exhaust valve E. The one-way valve assembly H includes a first one-way valve H1 and a second one-way valve H2. The first one-way valve H1 and the second one-way valve H2 are respectively arranged on the two booster pipelines where the booster pump 13 is located, and control the cooperation between the booster pump 13 and the intake pipeline. The drain valve D controls the drainage of the cooler 12. The cooler 12 also includes a compressed air pipeline 121. The exhaust valve E is arranged between the filter 16 and the sample gas flowmeter 17 to form a pressure relief pipeline.

[0030] Specifically, in the initial state: the first backflush valve V1, the second backflush valve V2, the fourth backflush valve V4, and the exhaust valve E are kept closed, and the third backflush valve V3 and the fifth backflush valve V5 are kept open.

[0031] Specifically, opening the first backflush valve V1 and closing the third backflush valve V3 are mainly used to purge the filter port 11 to avoid the long-term entry of compressed air into the sampling pipe.

[0032] Specifically, when the second backflush valve V2, the fourth backflush valve V4, the third backflush valve V3, and the exhaust valve E are opened and the fifth backflush valve V5 is closed, it is mainly to purge the front-section sampling intake pipeline for a short time and protect the booster pump 13. At this time, a small amount of gas will enter the sample gas flowmeter 17. The sample gas flowmeter 17 uses a float flowmeter, which has a certain effect of reducing the impact of the compressed air flow. At the same time, most of the compressed air is discharged through the exhaust valve E.

[0033] Specifically, during the process of gas measurement and backwashing, when the sample gas enters the intake pipeline through the filter port 11 and enters the intake pipeline, the third backwashing valve V3 is opened, the fifth backwashing valve V5 is opened, and the fourth backwashing valve V4 is closed. After the sample gas passes through the first one-way valve H1, the booster pump 13 starts to pressurize the gas. During the pressurization process of the booster pump 13, the first one-way valve H1 is closed. After the sample gas reaches a certain set pressure, the second one-way valve H2 is opened to convert the sample gas into positive pressure. Then the positive-pressure sample gas enters the visual filter 16 after being cooled by the cyclone cooler 12, then enters the sample gas flowmeter 17, and finally enters the electrochemical type measuring device 14 to detect the content of relevant gases.

[0034] Among them, the position of the booster pump 13 is placed in front, which can greatly reduce the length of the intake pipeline in the negative pressure state. It should be noted that when the intake pipeline is in the negative pressure state, this will cause external impurity gases to enter the pipeline, resulting in inaccurate later measurements. Therefore, the conversion of negative pressure and positive pressure by the booster pump 13 can greatly reduce the content of impurity gases entering the intake pipeline. And for the same principle, the more forward the position of the booster pump 13 and the booster pipeline, the more the length of the intake pipeline in the negative pressure state can be reduced, and the maintenance difficulty can be reduced.

[0035] It should be noted that when purging the sampling pipeline, the exhaust valve E is opened. First, there is an outlet for discharging the purged impurities to prevent coal ash from accumulating in the pipeline; second, it prevents the purged impurities from entering the subsequent measuring instruments, ensuring the stability and service life of the instrument operation.

[0036] Further, as shown in the appendix Figure 3 As shown, with the third backwashing valve V3 and the fifth backwashing valve V5 opened, and the fourth backwashing valve V4, the first backwashing valve V1, the second backwashing valve V2, and the exhaust valve E closed as the initial state, after starting the timing with a timer, purging begins. The booster pump 13 is stopped and the third backwashing valve V3 is closed, and the first backwashing valve V1 is opened for the first purge. Then the first backwashing valve V1 is closed, the second backwashing valve V2 and the exhaust valve E are opened for the second purge. Then the fifth backwashing valve V5 and the exhaust valve E are closed, and the third backwashing valve V3 and the fourth backwashing valve V4 are opened for the third purge. Subsequently, the second backwashing valve V2 and the fourth backwashing valve V4 are closed, and the fifth backwashing valve V5 is opened to end the purge. At this time, the booster pump 13 is started, and the purge timer starts timing again to form a cycle.

[0037] Finally, it should be pointed out that the methods and devices described in detail above are only examples, and those skilled in the art can modify these examples in different ways as long as they do not depart from the scope of the present invention.

Claims

1. A gas detection device under the condition of negative pressure and medium-temperature gas-solid two-phase, characterized in that: including, an intake module (1), which includes an intake component (11). The intake port of the intake component (11) can be filtered. The side walls at both ends of the intake component (11) are connected to an intake pipeline and an exhaust pipeline, and the intake pipeline is communicated with the exhaust pipeline through the intake component (11). A cooler (12), a booster pump (13), and a measuring device (14) are arranged on the intake pipeline, and an exhaust hole (15) is arranged at the end of the exhaust pipeline; a backflush module (2), which is connected to the intake module (1) through a pipeline. It includes a compressed air storage tank (21) and a backflush valve assembly (V) arranged on the pipeline. Gas is introduced into the intake pipeline to form several groups of backflush lines, and the on-off control of the backflush valve assembly (V) can guide the formation of different backflush lines.

2. The gas detection device under the negative pressure and medium temperature gas-solid two-phase working condition according to claim 1, characterized in that: The backflush valve assembly (V) is connected to the pipeline and includes a first backflush valve (V1), a second backflush valve (V2), and a third backflush valve (V3); The first backflush valve (V1) and the second backflush valve (V2) respectively connect the air storage tank (21) and the intake pipeline through pipelines to form a backflush line; The third backflush valve (V3) is arranged on the intake pipeline and controls the switching between the pipeline of the first backflush valve (V1) and the pipeline of the second backflush valve (V2).

3. The gas detection device under the negative pressure medium temperature gas-solid two-phase working condition according to claim 2, characterized in that: The cooler (12), the booster pump (13), and the measuring device (14) on the intake pipeline are arranged in sequence; The first backflush valve (V1) acts on the intake component (11), the second backflush valve (V2) acts in front of the cooler (12), and the third backflush valve (V3) acts on the intake pipeline and controls the splitting of the pipeline of the first backflush valve (V1) and the pipeline of the second backflush valve (V2); The backflush module (2) is finally discharged from the exhaust hole (15).

4. The gas detection device under the negative pressure medium temperature gas-solid two-phase working condition according to claim 2, characterized in that: The intake pipeline arranges the booster pump (13), the cooler (12), the filter (16), the sample gas flowmeter (17), and the measuring device (14) in sequence; The booster pump (13) is connected to the intake pipeline through a booster pipeline.

5. The gas detection device under the negative pressure and medium temperature gas-solid two-phase working condition according to claim 4, characterized in that: The backflush valve assembly (V) further includes a fourth backflush valve (V4) and a fifth backflush valve (V5). The fourth backflush valve (V4) is arranged on the intake pipeline and is between the pipelines of the third backflush valve (V3) and the second backflush valve (V2); One end of the booster pipeline is connected between the third backflush valve (V3) and the fourth backflush valve (V4), and the fifth backflush valve (V5) is arranged in this section; The other end of the booster pipeline is connected between the pipelines of the fourth backflush valve (V4) and the second backflush valve (V2).

6. The gas detection device under the negative pressure medium temperature gas-solid two-phase working condition according to claim 5, characterized in that: The intake module (1) further includes a check valve assembly (H), a drain valve (D), and an exhaust valve (E); The check valve assembly (H) includes a first check valve (H1) and a second check valve (H2). The first check valve (H1) and the second check valve (H2) are respectively arranged on the two booster pipelines where the booster pump (13) is located and control the cooperation between the booster pump (13) and the intake pipeline.

7. The gas detection device under the negative pressure medium temperature gas-solid two-phase working condition according to claim 6, characterized in that: The drain valve (D) controls the drainage of the cooler (12), and the cooler (12) further includes a compressed air pipeline (121).

8. The gas detection device under the negative pressure medium temperature gas-solid two-phase working condition according to claim 7, characterized in that: The exhaust valve (E) is arranged between the filter (16) and the sample gas flowmeter (17) to form a pressure relief pipeline.

9. A control method for a gas detection device under a negative pressure medium-temperature gas-solid two-phase working condition, characterized in that: A gas detection device under the negative pressure medium-temperature gas-solid two-phase working conditions according to any one of claims 1 to 8; and, with the third backflush valve (V3) and the fifth backflush valve (V5) opened, and the fourth backflush valve (V4), the first backflush valve (V1), the second backflush valve (V2) and the exhaust valve (E) closed as the initial state, different backflush lines are formed by controlling the valve switches through the PLC.

10. The control method of the gas detection device under the negative pressure and medium temperature gas-solid two-phase working condition according to claim 9, characterized in that: After timing by the timer, purging starts. The booster pump (13) is stopped, the third backflush valve (V3) is closed, and the first backflush valve (V1) is opened for primary purging. Then the first backflush valve (V1) is closed, the second backflush valve (V2) and the exhaust valve (E) are opened for secondary purging. Then the fifth backflush valve (V5) and the exhaust valve (E) are closed, and the third backflush valve (V3) and the fourth backflush valve (V4) are opened for the third purging. Subsequently, the second backflush valve (V2) and the fourth backflush valve (V4) are closed, and the fifth backflush valve (V5) is opened to end the purging. At this time, the booster pump (13) is started, and the purging timer starts timing again to form a cycle.

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