CN112246061B - A pre-placed high-temperature flue gas sampling and dust removal filtering device - Google Patents

Abstract

The present invention discloses a pre-placed high-temperature flue gas sampling dust removal and filtering device, wherein an inlet gas cavity is provided in a first cavity, a filter element is provided in the inlet gas cavity, an intermediate flue gas duct is provided on one side of the inlet gas cavity, the intermediate flue gas duct is connected to the inside of the first cavity through openings at both ends, the intermediate flue gas duct is connected to the inlet gas flue gas channel, the inlet gas cavity is not directly connected to the inlet gas flue gas channel and the intermediate flue gas duct, and an outlet gas flue gas channel connected to the inlet gas cavity is provided in the second cavity. The pre-placed high-temperature flue gas sampling dust removal and filtering device provided by the present invention, when the flue gas enters the second cavity from the first cavity by suction, the space becomes larger, the flow rate decreases, the dust particles are easy to settle, and are directly stored on the inner wall of the second cavity, completing the first step of the dust removal and collection process, the flue gas then enters the inlet gas cavity, the dust particles are automatically separated after passing through the filter element, completing the second step of the dust removal and collection process, and are discharged through the outlet gas flue gas channel, the structure is simple, and the dust removal and filtering effect is good.

Description

A pre-placed high-temperature flue gas sampling and dust removal filtering device

Technical Field

The invention belongs to the technical field of flue gas dust removal and filtering devices, and specifically relates to a pre-placed high-temperature flue gas sampling dust removal and filtering device.

Background Art

Coal-fired power plants produce a large amount of flue gas during the production process, which contains nitrogen oxides, sulfur oxides, carbon monoxide, dust, etc. Its direct emission will have a bad impact on the environment. Therefore, ultra-low emission transformation is required to achieve clean power generation of the unit. In order to detect the combustion of the unit, the content of flue gas components generated during combustion, and the performance evaluation after ultra-low emission transformation, it is necessary to sample and analyze the flue gas in the boiler flue. The conventional practice is to use a sampling device to take samples at the flue gas sampling point and then lead them to the flue gas analyzer for analysis through a connecting pipeline. A large amount of dust will be deposited in the sampling pipeline and is not easy to clean, resulting in different flow rates at each sampling point, and the continuity of sampling cannot be guaranteed, resulting in low detection efficiency. At the same time, at the temperature leaving the flue (such as after cooling the sampling tube), the dust has an adsorption effect on some pollutants, which will reduce the test accuracy and even affect the measurement results. Therefore, it is of great practical significance to develop and design a flue gas sampling and dust removal filter device that can remove dust in the high-temperature part. Not only is the difficulty of depositing and removing moisture in the sampled flue gas in the pipeline greatly reduced, but it can also greatly improve the detection efficiency and accuracy.

The Chinese patent, authorization announcement number CN209155389U, discloses a flue gas filter device, which is hollow inside and has a filter membrane and anhydrous silica gel. After the flue gas enters the filter device, the ash is filtered through the filter membrane, and the filter device is cleaned and replaced regularly. However, the filter membrane of the device can only be used for low-temperature flue gas, and dust will still clog the sampling steel pipe, affecting the measurement.

Chinese patent, authorization announcement number CN207036518U discloses an anti-blocking flue gas sampling device, which is divided into two parts, the upper part is provided with a partition to divide it into two spaces, which are used as the flue gas inlet and outlet respectively, and the silica gel desiccant is placed in the lower part. After the flue gas enters the filter device, it first passes through the filter to remove dust for the first time, and then passes through the filter to remove dust after returning, and the clean gas is discharged from the outlet. The filter device is cleaned and replaced regularly. However, the device does not have a space for separating dust and flue gas. The flue gas still needs to pass through a large amount of dust before entering the next level of filtration, which increases the suction resistance while still carrying dust in the flue gas, making the operation troublesome.

The currently disclosed technical solutions for solving the problem of dust removal and filtration in flue gas sampling are only suitable for dust removal in the low-temperature range and cannot solve the problem of dust removal in high-temperature sampling. In addition, the dust removal effect is poor after long-term use and dust cleaning is troublesome, which needs further improvement.

Summary of the invention

In order to solve the technical problems existing in the prior art, the purpose of the present invention is to provide a pre-high-temperature flue gas sampling dust removal and filtering device.

In order to achieve the above purpose and the above technical effect, the technical solution adopted by the present invention is:

A pre-placed high-temperature flue gas sampling, dust removal and filtering device comprises a hollow cavity, along the flue gas inlet direction, the cavity comprises a first cavity and a second cavity which are hollow and connected to each other, a hollow gas inlet cavity is arranged in the first cavity, a filter element is arranged in the gas inlet cavity, an intermediate gas pipe with two openings at both ends is arranged on the side of the gas inlet cavity facing away from the second cavity, the intermediate gas pipe is connected to the inside of the first cavity through the openings at both ends, the side of the intermediate gas pipe facing away from the gas inlet cavity is connected to the gas inlet gas channel, the gas inlet cavity is not directly connected to the gas inlet gas channel and the intermediate gas pipe, an outlet gas channel connected to the gas inlet cavity is arranged in the second cavity, and the outlet gas channel is connected to the sampling tube;

The flue gas enters the gas inlet flue gas channel, then enters the intermediate flue gas duct, is emitted into the first cavity from the openings at both ends of the intermediate flue gas duct, and then enters the second cavity. The particles in the flue gas are deposited on the inner wall of the second cavity. The flue gas then enters the gas inlet cavity and is filtered through the filter element. The flue gas is discharged into the sampling tube through the gas outlet flue gas channel, which is convenient for subsequent sampling, analysis and other steps.

Furthermore, the right side of the air inlet cavity is connected to the middle smoke duct through a cylindrical connecting block, the upper and lower ends and the middle right side openings of the middle smoke duct are connected to the interior of the first cavity, and the middle right side opening of the middle smoke duct is connected to the air inlet smoke channel.

Furthermore, the gas inlet cavity is opened on the left side, and a plurality of limit blocks are symmetrically arranged on the inner wall of the gas inlet cavity. The filter element is detachably installed in the gas inlet cavity through the left side opening of the gas inlet cavity and is limited by the limit blocks.

Furthermore, a coaxial gas inlet is detachably arranged on the right side of the first cavity, and a gas inlet smoke channel runs through the central position of the gas inlet, and the rightmost side of the gas inlet smoke channel is a smoke inlet.

Furthermore, a coaxial gas outlet is detachably arranged on the left side of the second cavity, and the right side of the gas outlet smoke channel passes through the gas outlet and extends into the gas inlet inner cavity, and the leftmost side of the gas outlet smoke channel is the smoke outlet.

Furthermore, it also includes a pump, which is arranged outside the front high-temperature flue gas sampling and dust removal filter device. Under the action of the pump, the flue gas enters the first cavity and the second cavity in turn through the gas inlet flue gas channel, and then is filtered through the filter element, and is discharged into the sampling tube through the gas outlet flue gas channel.

Furthermore, the right side of the first cavity is detachably provided with gas inlet through a first thread, and the left side of the second cavity is detachably provided with gas outlet through a second thread.

Furthermore, the gas inlet cavity, the first cavity, the gas inlet on the right side of the first cavity, the second cavity and the gas outlet on the left side of the second cavity all present a coaxial cylindrical structure, and the cylindrical diameter of the second cavity is greater than the cylindrical diameter of the first cavity.

Furthermore, the cylindrical diameter of the second cavity is not less than 1.2 times the cylindrical diameter of the first cavity.

Furthermore, the filter element is made of high temperature resistant filter material.

Furthermore, the high temperature resistant filter material includes any one of aluminum, stainless steel, and asbestos.

Compared with the prior art, the present invention has the following beneficial effects:

The present invention discloses a pre-positioned high-temperature flue gas sampling, dust removal and filtering device, comprising a cavity with a hollow interior. Along the direction of flue gas entering, the cavity comprises a first cavity with a hollow interior and a second cavity which are connected to each other. A hollow gas inlet cavity is arranged in the first cavity, a filter element is arranged in the gas inlet cavity, an intermediate gas pipe with openings at both ends is arranged on the side of the gas inlet cavity which is away from the second cavity, the intermediate gas pipe is connected to the interior of the first cavity through the openings at both ends, the side of the intermediate gas pipe which is away from the gas inlet cavity is connected to the gas inlet smoke channel, the gas inlet cavity is not directly connected to the gas inlet smoke channel and the intermediate gas pipe, and a gas outlet smoke channel connected to the gas inlet cavity is arranged in the second cavity. The pre-high temperature flue gas sampling dust removal and filtering device provided by the present invention has the advantages that the flue gas first enters the gas inlet flue gas channel, is emitted into the first cavity from the openings at both ends of the middle flue gas duct, and then enters the second cavity. When the flue gas enters the second cavity from the first cavity by suction, the space becomes larger and the flow rate decreases. Some dust particles in the flue gas are easy to settle and are directly stored on the inner wall of the second cavity with a larger volume, completing the first step of dust removal and collection process. Subsequently, the flue gas enters the gas inlet cavity and is filtered through the filter element. The flue gas and the dust particles therein are automatically separated after passing through the filter element, completing the second step of dust removal and collection process, and the flue gas is discharged through the gas outlet flue gas channel. The first cavity and the second cavity can be arranged to be threadedly connected or fixed as a whole according to actual needs. When there are many dust particles in the second cavity, the gas outlet can be opened to remove them. The overall structure is simple, the dust removal and filtering effect is good at high temperature, the installation is convenient during use, no consumables need to be replaced, and the filtered material is convenient to clean. The pre-dust removal and filtering for high temperature flue gas sampling can achieve good practical effects, help to improve detection efficiency and accuracy, and has broad application prospects.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a side view of the present invention;

Among them: 1. gas inlet; 2. gas outlet; 3. cavity; 4. filter element; 5. limit block; 10. flue gas inlet; 11. first thread; 12. gas inlet and flue gas channel; 13. gas inlet inner cavity; 14. intermediate flue gas duct; 15. connecting block; 20. flue gas outlet; 21. second thread connection; 22. gas outlet and flue gas channel; 31. second cavity; 32. first cavity.

DETAILED DESCRIPTION

The embodiments of the present invention are described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more definite definition of the protection scope of the present invention.

As shown in FIG1 , a pre-high-temperature flue gas sampling dust removal and filtering device is arranged at the front end of the sampling tube. The dust is first filtered by the dust removal and filtering device and then the sampling tube is used for subsequent sampling and analysis. The dust removal and filtering device includes an internal hollow cavity 3. To improve the dust removal effect, along the flue gas entry direction (from right to left), the cavity 3 includes an internal hollow and connected first cavity 32 and a second cavity 31. The first cavity 32 and the second cavity 31 can be arranged to be threadedly connected or fixed as a whole according to actual needs. A hollow gas inlet cavity 13 is arranged in the first cavity 32, and a filter element 4 is arranged in the gas inlet cavity 13. An intermediate gas duct 14 with openings at both ends is arranged on the side (right side) of the gas inlet cavity 13 facing away from the second cavity 31. The intermediate gas duct 14 is connected to the inside of the first cavity 32 through the openings at both ends. The side of the intermediate flue gas duct 14 facing away from the gas inlet cavity 13 is connected to the gas inlet flue gas channel 12, the gas inlet cavity 13 is not directly connected to the gas inlet flue gas channel 12 and the intermediate flue gas duct 14, and a gas outlet flue gas channel 22 connected to the gas inlet cavity 13 is arranged in the second cavity 31, and the gas outlet flue gas channel 22 is connected to the sampling tube; a pump is arranged outside the dust removal and filtering device, and under the suction of the pump, the flue gas enters the gas inlet flue gas channel 12, and then enters the intermediate flue gas duct 14, and is emitted from the openings at both ends of the intermediate flue gas duct 14 to the first cavity 32, and then enters the second cavity 31, and the particles in the flue gas are deposited on the inner wall of the second cavity 31, and the flue gas enters the gas inlet cavity 13 and is filtered by the filter element 4, and is discharged to the sampling tube connected thereto through the gas outlet flue gas channel 22.

The right side of the air intake cavity 13 is connected to the middle smoke duct 14 through a cylindrical connecting block 15, so that the air intake cavity 13 is not connected to the middle smoke duct 14, and the upper and lower ends and the middle right side of the middle smoke duct 14 are open. The upper and lower ends of the middle smoke duct 14 are connected to the inside of the first cavity 32, and the middle right side opening of the middle smoke duct 14 is connected to the air intake smoke channel 12.

The left side of the gas inlet cavity 13 is open to facilitate the insertion of the filter element 4. The filter element 4 can be completely inserted into the gas inlet cavity 13 according to actual conditions, or it can be partially inserted into the gas inlet cavity 13, that is, a part of the filter element 4 is inserted into the gas inlet cavity 13 and the remaining part is suspended in the second cavity 31. A number of limit blocks 5 are symmetrically arranged on the inner wall of the gas inlet cavity 13. The filter element 4 is detachably installed in the gas inlet cavity 13 through the left side opening of the gas inlet cavity 13, and is limited by the limit blocks 5 to prevent the filter element 4 from extending too deep into the gas inlet cavity 13 and being difficult to remove. The limit blocks 5 can adopt existing structures, such as protruding structures of various shapes.

A coaxial gas inlet 1 is detachably provided on the right side of the first cavity 32 through a first thread 11, and a gas inlet smoke passage 12 runs through the central position of the gas inlet 1. The rightmost side of the gas inlet smoke passage 12 is a smoke inlet 10, which serves as a smoke inlet.

A coaxial gas outlet 2 is detachably arranged on the left side of the second cavity 31 through the second thread 21, and the right side of the gas outlet smoke channel 22 penetrates the gas outlet 2 and extends into the gas inlet inner cavity 13. The leftmost side of the gas outlet smoke channel 22 is a smoke outlet 20, which serves as a smoke exhaust outlet. A pump is arranged at the smoke outlet 20 (not shown, an existing product can be used, mainly to maintain the negative pressure inside the device of the present invention). Under the action of the pump, the smoke passes through the gas inlet smoke channel 12 and enters the first cavity 32 and the second cavity 31 in turn, and is then filtered by the filter element 4 and discharged through the gas outlet smoke channel 22.

The gas inlet cavity 13, the first cavity 32, the gas inlet 1, the second cavity 31 and the gas outlet 2 are all coaxial cylindrical structures, which are connected as a whole by threads or contacts. The corresponding materials can be selected according to the flue temperature to adapt to the dust removal effect at different temperatures. The diameter of the second cavity 31 can be freely designed according to the sampling flow rate, but it is at least 1.2 times the diameter of the first cavity 32. When the flue gas enters the second cavity 31 from the first cavity 32 through the suction force of the pump, the space becomes larger, the flow rate decreases, the dust is easy to settle, and is directly stored in the larger second cavity 31.

The filter element 4 is made of aluminum, stainless steel, asbestos or other high temperature resistant filter materials. The length is flexibly adjusted according to the length of the gas inlet cavity 13. It can be disassembled and cleaned. Its main function is to filter dust particles.

The working principle of the present invention is:

Before working, place the filter element 4 in the gas inlet cavity 13, and after connecting all parts through matching threads, check the air tightness of the entire device to ensure that the air tightness meets the requirements;

The device is connected to the front end of the sampling tube by a hard connection such as a thread. Under the suction force of the pump, the flue gas is introduced from the flue gas inlet 10, and the flue gas enters the first cavity 32 of the cavity 3 through the upper and lower end openings of the inlet flue gas channel 12 and the intermediate flue gas duct 14, and then flows to the second cavity 31. After the flue gas enters the second cavity 31, the volume expands rapidly and the flow rate decreases. After contacting the inner wall of the second cavity 31, some particles in the flue gas are deposited on the inner wall of the second cavity 31, and the flue gas completes the first step of dust removal and collection process;

The flue gas then flows along the left opening of the gas inlet cavity 13 to the inside of the gas inlet cavity 13. The gas inlet cavity 13 has a built-in filter element 4. The dust particles are automatically separated after passing through the filter element 4. The flue gas completes the second step of dust removal and collection process.

The filtered flue gas leaves the dust removal and filtering device along the gas outlet flue gas channel 22. When there is a lot of dust in the second cavity 31, the gas outlet 2 can be opened to remove the dust.

Example 1

As shown in FIG1 , a pre-mounted high-temperature flue gas sampling and dust removal and filtering device is used for flue gas sampling for performance testing of an SCR denitrification device of a 1000MW coal-fired power generation unit, including an internal hollow cavity 3. To improve the dust removal effect, along the flue gas entry direction (from right to left), the cavity 3 includes an internal hollow and connected first cavity 32 and a second cavity 31. The first cavity 32 and the second cavity 31 can be arranged to be threadedly connected or fixed as a whole according to actual needs. A hollow gas inlet cavity 13 is arranged in the first cavity 32, and a filter element 4 is arranged in the gas inlet cavity 13. An intermediate flue gas duct 14 with openings at both ends is arranged on the right side of the gas inlet cavity 13 facing away from the second cavity 31. The intermediate flue gas duct 14 is connected to the interior of the first cavity 32 through the upper and lower openings. The intermediate flue gas duct 14 is connected to the interior of the first cavity 32 through the upper and lower openings. The channel 14 is facing away from the right opening of the gas inlet cavity 13 and is connected to the gas inlet flue gas channel 12. The gas inlet cavity 13 is not directly connected to the gas inlet flue gas channel 12 and the intermediate flue gas duct 14. A gas outlet flue gas channel 22 connected to the gas inlet cavity 13 is arranged in the second cavity 31. The gas outlet flue gas channel 22 is connected to the sampling tube. Under the action of suction, the flue gas enters the gas inlet flue gas channel 12, and then enters the intermediate flue gas duct 14. It is emitted outward from the upper and lower openings of the intermediate flue gas duct 14 to the first cavity 32, and then enters the second cavity 31. The particles in the flue gas are deposited on the inner wall of the second cavity 31. The flue gas enters the gas inlet cavity 13 and is filtered by the filter element 4, and is discharged to the sampling tube through the gas outlet flue gas channel 22, which is convenient for subsequent sampling and analysis.

The filtering device of the present invention is made of stainless steel, the first cavity 32 has a cylindrical diameter of 30 mm and a length of 80 mm, the second cavity 31 has a cylindrical diameter of 40 mm and a length of 80 mm; the cylindrical diameter of the gas inlet cavity 13 is 20 mm, the filter element 4 is made of asbestos and is 30 mm high, the cylindrical diameters of the gas inlet smoke channel 12 and the gas outlet smoke channel 22 are the same, both of which are 14 mm; the intermediate smoke duct 14 is a hollow cylindrical structure with openings at both ends, and the gas inlet cavity 13 and the intermediate smoke duct 14 are placed vertically; an external thread is provided at the smoke outlet 20 to connect with the sampling tube.

The continuous sampling test within 1 hour showed that the comprehensive dust filtration efficiency (by weight) of the filter device was about 99.9%. After the test, a large amount of dust particles were deposited in the second cavity 31, and there was some dust in the lower part of the filter element 4, while the upper part was clean. During the test, there was no blockage in the sampling pipeline, and the filter device did not need to be replaced. The dust particles were dry and easy to clean. After the test, the gas outlet 2 was opened and cleaned.

The modules not specifically described in the present invention may adopt existing products and will not be described in detail here.

The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims (7)

1. The front high-temperature flue gas sampling dust removal filtering device is characterized by comprising an inner hollow cavity (3), wherein the cavity (3) comprises a first cavity (32) and a second cavity (31) which are hollow in the interior and are communicated with each other, a hollow air inlet inner cavity (13) is arranged in the first cavity (32), a filter element (4) is arranged in the air inlet inner cavity (13), an intermediate flue gas pipeline (14) with two open ends is arranged on one side, facing away from the second cavity (31), of the air inlet inner cavity (13), the intermediate flue gas pipeline (14) is communicated with the interior of the first cavity (32) through the two open ends, one side, facing away from the air inlet inner cavity (13), of the intermediate flue gas pipeline (14) is communicated with an air inlet flue gas channel (12), the air inlet inner cavity (13) is not directly communicated with the air inlet flue gas channel (12) and the intermediate flue gas pipeline (14), an air outlet channel (22) communicated with the air inlet inner cavity (13) is arranged in the second cavity (31), and the air outlet flue gas channel (22) is communicated with a flue gas sampling pipe.

The flue gas enters a gas inlet flue gas channel (12), then enters a middle flue gas pipeline (14), is emitted into a first cavity (32) from openings at two ends of the middle flue gas pipeline (14), then enters a second cavity (31), particles in the flue gas are deposited on the inner wall of the second cavity (31), the flue gas then enters a gas inlet inner cavity (13), is filtered through a filter element (4), and is discharged through a gas outlet flue gas channel (22);

The gas inlet device comprises a gas inlet inner cavity (13), a first cavity (32), a gas inlet body (1) on the right side of the first cavity (32), a second cavity (31) and a gas outlet (2) on the left side of the second cavity (31), wherein the gas inlet inner cavity, the first cavity and the gas outlet inner cavity are all of coaxial cylinder structures, and the cylinder diameter of the second cavity (31) is larger than that of the first cavity (32).

2. The prepositive high-temperature flue gas sampling dust-removing filtering device according to claim 1 is characterized in that the right side of the air inlet inner cavity (13) is connected with a middle flue gas pipeline (14) through a connecting block (15) with a cylindrical structure, the upper end, the lower end and the right side middle opening of the middle flue gas pipeline (14), the upper end and the lower end openings of the middle flue gas pipeline (14) are communicated with the inside of the first cavity (32), and the right side middle opening of the middle flue gas pipeline (14) is communicated with the air inlet flue gas channel (12).

3. The preposed high-temperature flue gas sampling dust removal filtering device according to claim 1 is characterized in that a left side opening of an air inlet inner cavity (13), a plurality of limiting blocks (5) are symmetrically arranged on the inner wall of the air inlet inner cavity (13), and the filter element (4) is detachably arranged in the air inlet inner cavity (13) through the left side opening of the air inlet inner cavity (13) and limited through the limiting blocks (5).

4. The prepositive high-temperature flue gas sampling dust-removing filtering device according to claim 1 is characterized in that a coaxial air inlet body (1) is detachably arranged on the right side of the first cavity body (32), an air inlet body flue gas channel (12) penetrates through the central position inside the air inlet body (1), and a flue gas inlet (10) is arranged on the rightmost side of the air inlet body flue gas channel (12).

5. The prepositive high-temperature flue gas sampling dust-removing filtering device according to claim 1 is characterized in that a coaxial gas outlet (2) is detachably arranged on the left side of the second cavity (31), the right side of the gas outlet flue gas channel (22) penetrates through the gas outlet (2) and stretches into the gas inlet inner cavity (13), and the leftmost side of the gas outlet flue gas channel (22) is a flue gas outlet (20).

6. The front-end high-temperature flue gas sampling dust removal filter device according to claim 1, wherein the diameter of the cylinder of the second cavity (31) is not smaller than 1.2 times of the diameter of the cylinder of the first cavity (32).

7. The prepositive high-temperature flue gas sampling dust-removing filter device according to claim 1 is characterized in that the filter element (4) is made of a high-temperature resistant filter material.