Online detection device and method for particle size of particulate matter

Abstract

The invention discloses an online particle size detection device and method, and relates to the technical field of natural gas quality monitoring, the online particle size detection device comprises a gas inlet pipeline communicated with a natural gas pipeline, the gas inlet pipeline is connected with a pressure gauge, the gas inlet pipeline is connected with a gas conveying pipeline, and the gas conveying pipeline is connected with an optical sensor; the gas outlet end of the gas conveying pipeline is connected with the bottom of the optical sensor. The optical signal transmitting end and the optical signal receiving end of the optical sensor are located on the left side and the right side of the optical sensor respectively. The top of the optical sensor is connected with a dissolving tank; a natural gas solvent is placed in the dissolving tank; the particulate matter on-line detection device can achieve the effect that a sample is directly absorbed by a natural gas solvent after being detected, does not need to be discharged to the outside, prevents the discharged sample from polluting the environment, also avoids deflagration accidents, and has high popularization and application value in scientific research work.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas quality monitoring, and in particular to an online particle size detection device and method. Background Art

[0002] In order to control the content and particle size of particulate matter in natural gas, GB / T 37124-2018 "Quality Requirements for Gas Entering Long-distance Natural Gas Pipelines" clearly states that particulate matter in natural gas should not affect the transportation and utilization of gas, and the particle size of particulate matter should not be greater than 5μm. Therefore, it is necessary to monitor the particle size of particulate matter in natural gas in real time.

[0003] At present, there are related instruments for measuring particle size in natural gas at home and abroad, such as laser particle size analyzers and optical particle counters, which have been widely used in the natural gas industry. The detection process of existing detection devices is usually to transmit the natural gas containing dust particles in the natural gas pipeline to the laser particle size analyzer, detect it through optical signals, and the detected natural gas is discharged from the laser particle size analyzer and enters the filter to filter the particles in the natural gas before being discharged.

[0004] Although there are some instruments that can measure particulate matter in natural gas, these instruments use optical methods for measurement, and the sampled gas needs to be released inside or around the gathering and transportation station. This will not only pollute the surrounding environment, but also release it near the gathering and transportation station is likely to cause serious combustion and explosion accidents, posing a major hidden danger. Summary of the invention

[0005] The technical problem to be solved by the present invention is that the samples detected by the current natural gas particle detection device are directly released, which may cause pollution to the environment and even cause explosion accidents. The purpose is to provide an online particle size detection device and method. The natural gas samples detected by the detection device do not need to be discharged, which solves the problem that the samples detected by the current natural gas particle detection device are directly released, which may cause pollution to the environment and even cause explosion accidents.

[0006] The present invention is achieved through the following technical solutions:

[0007] In a first aspect, the present invention provides an online detection device for particle size of particulate matter, comprising an air intake pipe connected to a natural gas pipeline, the air intake pipe being connected to a pressure gauge, the air intake pipe being connected to a gas delivery pipe, the gas delivery pipe being connected to an optical sensor, the gas outlet end of the gas delivery pipe being connected to the bottom of the optical sensor, the optical signal emitting end and the optical signal receiving end of the optical sensor being respectively located on the left and right sides of the optical sensor; the top of the optical sensor is connected to a dissolving tank, and a natural gas solvent is placed in the dissolving tank.

[0008] The online particle detection device in the present invention can achieve the effect that the sample is directly absorbed by the natural gas solvent after detection, without the need to discharge it to the outside, thus avoiding the pollution of the environment by the discharged sample and also avoiding the occurrence of explosion accidents. It has a high promotion and application value in scientific research work.

[0009] A natural gas solvent placement port is provided on the device shell where the dissolving tank is set, and a seal that can be opened and closed is connected to the placement port, through which the natural gas solvent is replaced or added.

[0010] Among them, the natural gas solvent is n-hexane.

[0011] In addition, the natural gas solvent can also be a natural gas solvent prepared by adding a binder to lignite, candle coal or lignin as raw materials. The binder is chitosan acetamide urea. The preparation method of the binder is:

[0012] 1) adding semicarbazide hydrochloride and potassium carbonate to dichloromethane in an ice bath and mixing them evenly to obtain a first reaction solution, maintaining the temperature of the first reaction solution at 0° C. to 5° C., adding a dichloromethane solution of acrylamide hydrochloride, and reacting at room temperature until termination to obtain a reaction product;

[0013] 2) washing the obtained reaction product with ether, adjusting the pH to 6-7, and finally freeze-drying it, and washing and recrystallizing it with an alcohol solution to obtain acrylamide urea;

[0014] 3) preparing acrylamide urea into a solution and mixing it with a chitosan acid solution, adding an alkaline catalyst solution with a pH value of 5 to 7, reacting at a temperature of 55 to 75° C. until completion, and then concentrating, dialyzing, and drying to obtain chitosan acetamide urea.

[0015] The above binder is used to prepare natural gas solvent:

[0016] 4) Carbonizing lignite, candle coal or lignin to obtain a carbonized material, soaking the carbonized material in a sodium hydroxide or potassium hydroxide solution, and then placing it in a rotary kiln under an inert gas atmosphere and heating it to 700-800° C., maintaining the activation time for 1-2 hours, and then cooling it;

[0017] 5) Wash the cooled carbon material with water to adjust the pH to 7, and then dry it to obtain a powdery material. Add the chitosan acetamide urea to the powdery material, mix well, knead and shape in a molding machine, and then dry to obtain a natural gas solvent.

[0018] The binder (chitosan acetamide urea) used in the natural gas solvent has abundant amide groups, which can play multiple intermolecular hydrogen bonds to form a hydrogen bond network structure around lignite, charcoal or lignin. On the one hand, the mechanical strength of the natural gas solvent protective layer is improved. On the other hand, as a group rich in arc pair electrons, amide has a very strong adsorption capacity. At the same time, chitosan acetamide urea can also form a three-dimensional network structure in situ on the interface of lignite, charcoal or lignin raw materials, so that the binder can tightly adhere to the lignite, charcoal or lignin raw materials, effectively improving the adhesion capacity.

[0019] Furthermore, the air intake pipe is threadedly connected to the gas delivery pipe.

[0020] The air intake pipe and the gas delivery pipe in the present invention are connected by threads, which makes it easy to install and disassemble the air intake pipe and the gas delivery pipe.

[0021] Furthermore, a regulating valve is connected to the gas delivery pipeline.

[0022] By connecting the regulating valve to the gas delivery pipeline, the present invention enables the staff to adjust the opening degree of the regulating valve according to actual conditions when the device is running, thereby adjusting the air intake volume, making the detection process safer and the detection result more accurate.

[0023] Furthermore, a gas distribution structure is connected to the connection point between the gas delivery pipeline and the optical sensor.

[0024] Furthermore, the gas distribution structure includes a bucket-shaped gas inlet connected to the gas delivery pipeline, and the top of the bucket-shaped gas inlet is connected to a gas distribution mesh plate.

[0025] Furthermore, the gas distribution mesh plate is composed of a plurality of gas pipes interconnected with each other, each of the gas pipes is provided with a plurality of gas outlet holes, and any one of the gas pipes is provided with an opening connected to the bucket-shaped air inlet.

[0026] By setting up a gas distribution structure, the present application can make the gas dispersion more uniform when the sample gas enters the optical sensor for detection, thereby further improving the accuracy of the particle size detection results.

[0027] Furthermore, the bucket-shaped air inlet is connected to the opening of the pipeline by welding.

[0028] In addition to being connected by welding, the bucket-shaped air inlet and the opening of the pipeline can also be connected by threaded connection. When the threaded connection is used, a sealing ring can be added at the connection to achieve sealing of the connection and prevent leakage of sample gas during transportation.

[0029] Furthermore, an air pressure buffer chamber is connected above the optical sensor, and a dissolving tank is connected above the buffer chamber.

[0030] The present application connects an air pressure buffer chamber above the optical sensor, which can provide a certain buffering effect on the air pressure in the device, thereby enhancing the safety of the device during operation.

[0031] Furthermore, there are multiple dissolving tanks, each of which is formed by two intersecting plates forming a V-shaped groove, the natural gas solvent is placed in the V-shaped groove with the opening facing upward, baffles are set at both ends of the V-shaped groove to close it, and there is a gap between adjacent dissolving tanks for gas circulation.

[0032] By setting up multiple dissolution tanks on the top of the optical sensor, the present application can place natural gas solvents in the dissolution tanks in different areas, thereby improving the dissolution efficiency of natural gas and avoiding the situation where the natural gas dissolves too slowly and causes the gas pressure in the optical sensor to be too high, which may cause danger.

[0033] In the second aspect, the present application provides an online detection method for particle size, which uses the above-mentioned online detection device for detection. The specific method is: natural gas containing particulate matter enters from the bottom of the optical sensor through a gas transmission pipeline, and the particulate matter content and particle size in the natural gas are detected through the cooperation of the optical signal transmitting end and the optical signal receiving end of the optical sensor. The natural gas after detection enters the dissolution tank at the top of the optical sensor and is absorbed and dissolved by the natural gas solvent in the dissolution tank.

[0034] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0035] (1) The online particle detection device of the present invention can achieve the effect that the sample is directly absorbed by the natural gas solvent after detection, without the need to discharge it to the outside, thus avoiding the pollution of the discharged sample to the environment and also avoiding the occurrence of explosion accidents, and has a high promotion and application value in scientific research work;

[0036] (2) The air intake pipe and the gas delivery pipe in the present invention are connected by threads, which makes it easy to install and disassemble the air intake pipe and the gas delivery pipe;

[0037] (3) By connecting a regulating valve to the gas delivery pipeline, the present invention allows the operator to adjust the opening degree of the regulating valve according to actual conditions when the device is in operation, thereby adjusting the intake volume, making the detection process safer and the detection results more accurate;

[0038] (4) By setting up a gas distribution structure, the present application can make the gas distribution more uniform when the sample gas enters the optical sensor for detection, further improving the accuracy of the particle size detection result;

[0039] (5) The present application connects an air pressure buffer chamber between the optical sensor and the dissolution tank, which can provide a certain buffering effect on the air pressure in the device, thereby enhancing the safety of the device during operation;

[0040] (6) By setting up multiple dissolution tanks on the top of the optical sensor, the present application can place natural gas solvents in the dissolution tanks in different areas, thereby improving the dissolution efficiency of natural gas and avoiding the situation where the natural gas dissolves too slowly and causes the gas pressure in the optical sensor to be too high, which may cause danger. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0042] Figure 1 It is a structural schematic diagram of an online particle size detection device in the prior art;

[0043] Figure 2 This is a schematic structural diagram of an online particle size detection device in Example 1 of the present invention;

[0044] Figure 3 This is a schematic structural diagram of an online particle size detection device in Example 2 of the present invention;

[0045] Figure 4 This is a schematic structural diagram of an online particle size detection device in Example 3 of the present invention;

[0046] Figure 5 Schematic diagram of the structure of the air distribution mesh plate in Example 3 of the present invention.

[0047] Marks and corresponding parts names in the attached drawings:

[0048] 01- natural gas pipeline, 02- air inlet pipeline, 03- pressure gauge, 04- regulating valve, 05- gas transmission pipeline, 06- optical sensor, 07- optical signal receiving end, 08- optical signal transmitting end, 09- filter, 10- dissolving tank, 11- air pressure buffer chamber, 12- air distribution mesh plate, 13- bucket-shaped air inlet, 14- gas pipeline, 15- air outlet. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0050] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0052] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, a connection or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0053] Example 1

[0054] like Figure 2 As shown, this embodiment provides an online detection device for particle size of particulate matter, including an air intake pipe 02 connected to a natural gas pipeline 01, a pressure gauge 03 connected to the air intake pipe 02, a gas delivery pipe 05 connected to the air intake pipe 02, the gas delivery pipe 05 connected to an optical sensor 06, an air outlet end of the gas delivery pipe 05 is connected to the bottom of the optical sensor 06, an optical signal transmitting end 08 and an optical signal receiving end 07 of the optical sensor 06 are respectively located on the left and right sides of the optical sensor 06; a dissolving tank 10 is connected to the top of the optical sensor 06, and n-hexane is placed in the dissolving tank 10.

[0055] Specifically, the air intake pipe 02 is threadedly connected to the gas delivery pipe 05. The air intake pipe 02 and the gas delivery pipe 05 are threadedly connected, so that the air intake pipe 02 and the gas delivery pipe 05 are easy to install and disassemble.

[0056] Specifically, a regulating valve 04 is connected to the gas delivery pipeline 05. By connecting the regulating valve 04 to the gas delivery pipeline 05, when the device is running, the staff can adjust the opening degree of the regulating valve 04 according to the actual situation, thereby adjusting the air intake, making the detection process safer and the detection results more accurate.

[0057] Specifically, there are multiple dissolving tanks 10, each of which is formed of a V-shaped groove formed by two intersecting plates. The natural gas solvent is placed in the V-shaped groove with the opening facing upward. The two ends of the V-shaped groove are closed with baffles, and there is a gap for gas circulation between adjacent dissolving tanks 10. By setting multiple dissolving tanks 10 on the top of the optical sensor 06, the natural gas solvent can be placed in the dissolving tanks 10 in different areas, thereby improving the dissolution efficiency of the natural gas and avoiding the danger caused by the excessively high gas pressure in the optical sensor 06 due to the slow dissolution of the natural gas.

[0058] The method of using the online particle size detection device in this embodiment is as follows: natural gas containing particulate matter enters from the bottom of the optical sensor 06 through the gas transmission pipeline 05, and the particulate matter content and particle size in the natural gas are detected through the cooperation of the optical signal transmitting end 08 and the optical signal receiving end 07 of the optical sensor 06. The natural gas after detection enters the dissolution tank 10 at the top of the optical sensor 06 and is absorbed and dissolved by the natural gas solvent in the dissolution tank 10.

[0059] like Figure 1 As shown, it is an existing online particle size detection device. When in use, natural gas containing particulate matter in natural gas pipeline 01 enters from the left side of optical sensor 06 through gas transmission pipeline 05, and the particulate matter content and particle size in natural gas are detected through the cooperation of optical signal transmitting end 08 and optical signal receiving end 07 of optical sensor 06, and then discharged from the right side of optical sensor 06 to filter 09 for discharge after filtration.

[0060] Compared with the existing online particle size detection device, the online particle detection device in this embodiment can achieve the effect of directly absorbing the sample by the natural gas solvent after detection, without the need to discharge it to the outside, thus avoiding the pollution of the discharged sample to the environment, and also avoiding the occurrence of explosion accidents. It has a high promotion and application value in scientific research work.

[0061] Example 2

[0062] like Figure 3 As shown, this embodiment provides an online particle size detection device, which is different from the first embodiment in that the optical sensor 06 of this embodiment is connected to a gas pressure buffer chamber 11 above, and the buffer chamber is connected to a dissolution tank 10 above. Other technical features are exactly the same as those of the first embodiment.

[0063] Compared with Example 1, the advantage of this embodiment is that by connecting the air pressure buffer chamber 11 above the optical sensor 06, a certain buffering effect can be exerted on the air pressure in the device, thereby enhancing the safety of the device during operation.

[0064] Example 3

[0065] like Figure 4 and Figure 5 As shown, this embodiment is an online detection device for particle size. Different from Embodiment 1, a gas distribution structure is connected at the connection between the gas delivery pipeline 05 and the optical sensor 06 in this embodiment.

[0066] Specifically, the gas distribution structure includes a bucket-shaped gas inlet 13 connected to the gas delivery pipeline 05 , and the top of the bucket-shaped gas inlet 13 is connected to a gas distribution mesh plate 12 .

[0067] Specifically, the gas distribution mesh plate 12 is composed of a plurality of gas pipes 14 interconnected with each other, each gas pipe 14 is provided with a plurality of gas outlet holes 15 , and any gas pipe 14 is provided with an opening connected to the bucket-shaped air inlet 13 .

[0068] Other technical features are exactly the same as those in Example 2.

[0069] Compared with Example 2, the advantage of this embodiment is that by setting up the gas distribution structure, the gas dispersion of the sample gas can be more uniform when it enters the optical sensor 06 for detection, further improving the accuracy of the particle size detection result.

[0070] Example 4

[0071] Based on Example 1, this example provides a particle size detection device. The difference from Example 1 is that the natural gas solvent used in this example is a natural gas solvent prepared by adding a binder using lignite as a raw material, and the other technical features are exactly the same as those of Example 1. The binder is chitosan acetamide urea.

[0072] The preparation method of the binder is:

[0073] S1: adding semicarbazide hydrochloride and potassium carbonate to dichloromethane in an ice bath and mixing them evenly to obtain a first reaction solution, maintaining the temperature of the first reaction solution at 3° C., adding a dichloromethane solution of acrylamide hydrochloride, and reacting at room temperature until termination to obtain a reaction product;

[0074] S2: washing the obtained reaction product with ether, adjusting the pH to 6, and finally freeze-drying it, and washing and recrystallizing it with an alcohol solution to obtain acrylamide urea;

[0075] S3: After preparing acrylamide urea into a solution, it is mixed with an acidic chitosan solution, and an alkaline catalyst solution with a pH value of 6 is added. The reaction is carried out at a temperature of 60 °C until it ends. Subsequently, it is concentrated, dialyzed, and dried to obtain chitosan acetamide urea.

[0076] The following binder is used to prepare a natural gas solvent:

[0077] S4: Lignite is carbonized to obtain a carbonized material. The carbonized material is soaked in a sodium hydroxide or potassium hydroxide solution and then placed in a rotary kiln under an inert gas atmosphere and heated to 750 °C. The activation time is maintained for 1.5 hours, and then it is cooled.

[0078] S5: The cooled carbon material is washed with water to make the pH = 7, and then dried to obtain a powdery material. Then, the above-mentioned chitosan acetamide urea is added to the powdery material. After mixing evenly, it is kneaded and formed in a molding machine. After drying, a natural gas solvent is prepared.

[0079] The binder (chitosan acetamide urea) used in this natural gas solvent has rich amide groups, which can form a hydrogen bond network structure around lignite, cannel coal or lignin by means of multiple intermolecular hydrogen bond actions. On the one hand, the mechanical strength of the natural gas solvent protection layer is improved. On the other hand, as a group rich in lone pair electrons, the amide has a very strong adsorption ability. At the same time, chitosan acetamide urea can also in-situ form a three-dimensional network structure at the interface of lignite, cannel coal or lignin raw materials, so that this binder can tightly adhere lignite, cannel coal or lignin raw materials, effectively improving the adhesion ability.

[0080] The above specific embodiments have further detailed the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An online particle size detection device, comprising an air intake pipeline (02) connected to a natural gas pipeline (01), a pressure gauge (03) connected to the air intake pipeline (02), a gas delivery pipeline (05) connected to the air intake pipeline (02), an optical sensor (06) connected to the gas delivery pipeline (05), It is characterized in that The gas outlet end of the gas delivery pipeline (05) is connected to the bottom of the optical sensor (06); the optical signal transmitting end (08) and the optical signal receiving end (07) of the optical sensor (06) are respectively located on the left and right sides of the optical sensor (06); the top of the optical sensor (06) is connected to a dissolving tank (10), and a natural gas solvent is placed in the dissolving tank (10).

2. The on-line particle size detection device according to claim 1, It is characterized in that The air intake pipe (02) is threadedly connected to the gas delivery pipe (05).

3. The on-line particle size detection device according to claim 1, It is characterized in that The gas delivery pipeline (05) is connected to a regulating valve (04).

4. The on-line particle size detection device according to claim 1, It is characterized in that The gas delivery pipeline (05) and the optical sensor (06) are connected to a gas distribution structure.

5. The on-line particle size detection device according to claim 4, It is characterized in that The gas distribution structure comprises a bucket-shaped gas inlet (13) connected to the gas delivery pipeline (05), and the top of the bucket-shaped gas inlet (13) is connected to a gas distribution mesh plate (12).

6. The on-line particle size detection device according to claim 5, It is characterized in that The gas distribution mesh plate (12) is composed of a plurality of gas pipelines (14) interconnected with each other, each of the gas pipelines (14) is provided with a plurality of gas outlet holes (15), and any one of the gas pipelines (14) is provided with an opening connected to the bucket-shaped air inlet (13).

7. The on-line particle size detection device according to claim 6, It is characterized in that The bucket-shaped air inlet (13) is connected to the opening of the pipeline by welding.

8. The on-line particle size detection device according to claim 1, It is characterized in that An air pressure buffer chamber (11) is connected above the optical sensor (06), and a dissolving tank (10) is connected above the buffer chamber.

9. The on-line particle size detection device according to claim 1, It is characterized in that There are a plurality of dissolving tanks (10), each of which is formed of two mutually intersecting plates forming a V-shaped groove, baffles are arranged at both ends of the V-shaped groove to seal it, the natural gas solvent is placed in the V-shaped groove with the opening facing upward, and there is a gap between adjacent dissolving tanks (10) for gas circulation.

10. A method for online detection of particle size, It is characterized in that The online detection device according to any one of claims 1 to 9 is used, and the specific method is: natural gas containing particulate matter enters from the bottom of the optical sensor (06) through the gas transmission pipeline (05), and the particulate matter content and particle size in the natural gas are detected through the cooperation of the optical signal transmitting end (08) and the optical signal receiving end (07) of the optical sensor (06). The natural gas after detection enters the dissolution tank (10) at the top of the optical sensor (06) and is absorbed and dissolved by the natural gas solvent in the dissolution tank (10).

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