Device, system and method for recycling and reusing analytical gas obtained from methanol cracking for hydrogen production

Abstract

An embodiment of the present application provides a device, a system and a method for recycling and reusing the analysis gas in methanol cracking for hydrogen production. The device for recycling and reusing the analysis gas in methanol cracking for hydrogen production is arranged behind the adsorption equipment for methanol cracking for hydrogen production, and includes the following equipment connected in sequence: a first analysis gas buffer tank, a second analysis gas buffer tank and an analysis gas compressor; wherein, the first analysis gas buffer tank is connected to the adsorption equipment through a first pipeline, and a first programmable control valve is arranged on the first pipeline; the second analysis gas buffer tank is connected to the adsorption equipment through a second pipeline, and a second programmable control valve is arranged on the second pipeline. On the one hand, this device and system solve the problem of environmental pollution caused by directly discharging the analysis gas, and on the other hand, reuse the waste gas as a raw material, reduce the unit consumption of methanol, save raw material resources and reduce production costs.

Description

Technical Field

[0001] The present application relates to the technical field of alcohol cracking, and particularly to a device, a system and a method for recycling and reusing the desorbed gas in methanol cracking to produce hydrogen. Background Art

[0002] In the process of methanol cracking to produce hydrogen, the obtained hydrogen is mixed with various impurity gases. Usually, pressure swing adsorption technology is used to purify hydrogen. In the current pressure swing adsorption device, while purifying hydrogen, during the reverse blow process, carbon monoxide, carbon dioxide, and a very small amount of methane and hydrogen are directly discharged into the atmosphere. As intermediate and final products of methanol cracking, carbon monoxide and hydrogen are directly discharged into the atmosphere, which not only causes environmental pollution but also wastes available energy. Moreover, the desorbed gas and air will form an explosive mixture. Continuously discharging it into the atmosphere may cause the flare stack to catch fire, posing a safety hazard. Therefore, there is an urgent need for a desorbed gas recycling and reusing device to solve the environmental pollution problem caused by the direct discharge of desorbed gas. Summary of the Invention

[0003] Embodiments of the present application provide a device for recycling and reusing the desorbed gas in methanol cracking to produce hydrogen to solve or alleviate one or more technical problems in the prior art.

[0004] As an aspect of the embodiments of the present application, an apparatus for recycling and reusing the desorbed gas in methanol cracking to produce hydrogen is provided. The apparatus is arranged after the adsorption equipment in methanol cracking to produce hydrogen, and the apparatus includes the following equipment connected in sequence: a first desorbed gas buffer tank, a second desorbed gas buffer tank, and a desorbed gas compressor;

[0005] Wherein, the first desorbed gas buffer tank is connected to the adsorption equipment through a first pipeline, and a first program-controlled valve is arranged on the first pipeline;

[0006] The second desorbed gas buffer tank is connected to the adsorption equipment through a second pipeline, and a second program-controlled valve is arranged on the second pipeline.

[0007] In one embodiment, a first filter is further arranged between the first desorbed gas buffer tank and the first program-controlled valve.

[0008] In one embodiment, a pressure gauge is arranged on the pipeline connecting the first filter and the first desorbed gas buffer tank.

[0009] In one embodiment, a third desorbed gas buffer tank is further connected between the second desorbed gas buffer tank and the desorbed gas compressor; a water washing tower is further connected after the desorbed gas compressor.

[0010] In one embodiment, the following equipment is also connected between the analytical gas compressor and the water washing tower: a second filter.

[0011] In one embodiment, valves are provided between each piece of equipment.

[0012] In one embodiment, the valves between the first analytical gas buffer tank and the second analytical gas buffer tank successively include a front stop valve, a pressure reducing valve, and a rear stop valve.

[0013] In one embodiment, the volume of the first analytical gas buffer tank is 75 - 85 m 3 , and the volume of the second analytical gas buffer tank is 3 - 5 m 3 ; the settings of the volumes of the first analytical gas buffer tank and the second analytical gas buffer tank are determined according to the amount of analytical gas generated in the early stage of reverse release.

[0014] As another aspect of the embodiments of the present application, the embodiments of the present application provide a methanol cracking hydrogen production analytical gas recovery and reuse system, including: the analytical gas recovery and reuse device according to any one of the above embodiments.

[0015] As another aspect of the embodiments of the present application, the embodiments of the present application provide an analytical gas recovery and reuse method, including the following steps: (1) When the pressure of the analytical gas is higher than 25 kPa, the analytical gas is successively introduced into the first analytical gas buffer tank and the second analytical gas buffer tank and flows to the analytical gas compressor; (2) When the pressure of the analytical gas drops to not more than 25 kPa, the analytical gas is directly introduced into the second analytical gas buffer tank and flows to the analytical gas compressor.

[0016] The methanol cracking hydrogen production analytical gas recovery and reuse device and system provided by the embodiments of the present application, on the one hand, solve the problem of environmental pollution caused by the direct discharge of analytical gas, and on the other hand, reuse the waste gas as a raw material, reduce the single consumption of methanol, save raw material resources, and reduce production costs.

[0017] The above summary is only for the purpose of the specification and is not intended to be limiting in any way. In addition to the above-described illustrative aspects, embodiments, and features, further aspects, embodiments, and features of the present application will be readily apparent by reference to the drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the drawings, unless otherwise specified, the same reference numerals throughout the several views denote the same or similar components or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application.

[0019] Figure 1Schematic diagram showing a device for recovering and recycling the analysis gas produced by methanol cracking to produce hydrogen according to an embodiment of the present application.

[0020] Reference numerals:

[0021] 1 - First program control valve; 2 - Second program control valve; 3 - First filter;

[0022] 4 - First analysis gas buffer tank; 5 - Pressure reducing valve; 6 - Second analysis gas buffer tank;

[0023] 7 - Third analysis gas buffer tank; 8 - Analysis gas compressor; 9 - Second filter;

[0024] 10 - Water washing tower; 11 - Reverse discharge pipe. Detailed implementation manners

[0025] In the following, only some exemplary embodiments are simply described. As those skilled in the art can recognize, the described embodiments can be modified in various different ways without departing from the spirit or scope of the present application. Therefore, the drawings and the description are considered to be exemplary in nature rather than restrictive.

[0026] Figure 1 Schematic diagram showing a device for recovering and recycling the analysis gas produced by methanol cracking to produce hydrogen according to an embodiment of the present application. As Figure 1 shown, the device may include: a first program control valve 1, a second program control valve 2, and the following devices connected in sequence: a first filter 3, a first analysis gas buffer tank 4, a second analysis gas buffer tank 6, a third analysis gas buffer tank 7, an analysis gas compressor 8, a second filter 9, and a water washing tower 10.

[0027] Since white powder is generated in the adsorption device for methanol cracking to produce hydrogen after pressure swing adsorption, a first filter 3, a second filter 9, and a water washing tower 10 are provided in the analysis gas recovery and recycling device to precipitate the white powder and prevent blockage of the entire device. The first analysis gas buffer tank 4, the second analysis gas buffer tank 6, and the third analysis gas buffer tank 7 are provided to stabilize the work of the hydrogen compressor.

[0028] Among them, the first analysis gas buffer tank 4 is connected to the adsorption device through a first pipeline, and a first program control valve 1 is provided on the first pipeline.

[0029] The second analysis gas buffer tank 6 is connected to the adsorption device through a second pipeline, and a second program control valve 2 is provided on the second pipeline.

[0030] In one example, a pressure gauge is provided on the pipeline connecting the first filter 3 and the first analysis gas buffer tank 4.

[0031] In one example, a valve is provided between each device.

[0032] In one example, the valves between the first desorbed gas buffer tank 4 and the second desorbed gas buffer tank 6 sequentially include a front stop valve, a pressure reducing valve 5, and a rear stop valve.

[0033] In one example, the volume of the first desorbed gas buffer tank 4 is 80 m 3 , and the volume of the second desorbed gas buffer tank 6 is 4 m 3 .

[0034] As another aspect of the embodiments of the present application, the embodiments of the present application provide a methanol cracking hydrogen production desorbed gas recovery and reuse system, including the desorbed gas recovery and reuse device of any of the above embodiments.

[0035] As another aspect of the embodiments of the present application, the embodiments of the present application provide a desorbed gas recovery and reuse method, including the following steps: (1) When the pressure of the desorbed gas is higher than 25 kPa, the desorbed gas sequentially passes through the first desorbed gas buffer tank 4 and the second desorbed gas buffer tank 6 and flows to the desorbed gas compressor 8; (2) When the pressure of the desorbed gas drops to no more than 25 kPa, the desorbed gas directly enters the second desorbed gas buffer tank 6 and flows to the desorbed gas compressor 8.

[0036] The desorbed gas recovery and reuse device provided by the embodiments of the present application controls the desorbed gas generated by pressure swing adsorption through two program control valves at the end of the adsorption tower pipeline, and divides it into two paths to enter the desorbed gas buffer system. One path is: Since under high pressure, the desorbed gas will wash away some adsorbents in the adsorption tower, therefore, it first enters the first filter 3 to filter out the adsorbents brought by the desorbed gas. Further, since the amount of desorbed gas generated in the early stage of reverse pressure release is large, it first enters the 80 m 3 buffer tank (i.e., the first desorbed gas buffer tank 4, and the entering gas is 12.075 cubic meters), and then enters the 4 m 3 buffer tank (i.e., the second desorbed gas buffer tank 6, and the pressure of the 4 m 3 buffer tank is controlled to be 18 kPa through a regulating valve); the other path is: When the pressure of the desorbed gas is about 25 kPa, it directly enters the 4 m 3 buffer tank (i.e., the second desorbed gas buffer tank 6, and the entering gas is 0.495 cubic meters); then they enter the desorbed gas inlet buffer tank (the third desorbed gas buffer tank 7) together; then enter the desorbed gas compressor 8, after being pressurized by the compressor, enter the second filter 9, and then pass through the water washing tower 10 to wash away a small amount of adsorbents and a small amount of impurities such as methane brought from the compressor, and finally send it to the methanol cracking system for reuse. Thus, it is ensured that the pressurized desorbed gas coming out of the pressure swing adsorption becomes a stable atmospheric pressure state before entering the desorbed gas compressor 8, reducing the impact on the compressor.

[0037] The parameters of the above-mentioned first filter 3 are as follows: 1) Model: NYB-30; 2) Filter area: 30 square meters; 3) Filter cake volume: 600L; Rated working pressure: 0.1 - 0.4 MPa; Maximum working pressure: 0.5 MPa; Working temperature: ≤150 °C; Volume: 2300L.

[0038] The parameters of the above-mentioned second filter 9 are as follows: 1) Design pressure: 2.5 MPa; 2) Working pressure: 2.2 MPa; 3) Volume: 1.18m 3 ; 4) Design temperature: 60 degrees. This filter relies on adsorbents to filter the desorbed gas.

[0039] The parameters of the above-mentioned desorbed gas hydrogen compressor 8 are as follows: 1) Model: DW-15 / 23; 2) Power: 220 kW; 3) Flow rate: 900m 3 / H; 4) Outlet pressure: 2.3 MPa.

[0040] The two programmable control valves at the end of the adsorption tower pipeline are the first programmable control valve 1 and the second programmable control valve 2 respectively, to control the desorbed gas to enter the desorbed gas buffer system in two paths. The first programmable control valve 1 controls the high-pressure desorbed gas (about 0.15 MPa) coming out of the adsorption tower, and the second programmable control valve 2 controls the low-pressure desorbed gas (about 25 kPa). The above-mentioned first filter 3 is equipped with an inlet pipeline and an outlet pipeline, and the outlet pipeline is connected to an 80m 3 buffer tank, and a pressure gauge is installed on the outlet pipeline. The 80m 3 buffer tank outlet is equipped with front and rear stop valves, a pressure reducing valve 5 (control valve), and is connected to a 4m 3 buffer tank, and a bypass line is also provided for the maintenance of the pressure reducing valve 5 (control valve). The 4m 3 buffer tank is connected to the desorbed gas inlet buffer tank (the third desorbed gas buffer tank 7), and the pressure of this buffer tank is about 0.001 MPa, meeting the inlet pressure requirements of the desorbed gas compressor 8. A desorbed gas outlet filter (the second filter 9) is provided between the desorbed gas compressor 8 and the water washing tower 10. The desorbed gas after being compressed by the desorber needs to pass through the desorbed gas outlet filter to filter impurities such as carbon dioxide. After passing through the desorbed gas outlet filter, it still needs to enter the desorbed gas water washing tower to further wash away a small amount of adsorbents and a small amount of methane before entering the methanol cracking system.

[0041] Through the above operations, the desorbed gas generated after pressure swing adsorption enters the desorbed gas buffer system in two paths, and finally enters the desorbed gas compressor 8. After being pressurized by the compressor, it is sent to the methanol cracking system to reuse carbon monoxide and a small amount of hydrogen, thus achieving the purpose of recycling and reusing the desorbed gas generated by methanol cracking through pressure swing adsorption and reducing costs.

[0042] For other components of the methanol cracking hydrogen production and analytic gas recovery and reuse device and system of the above embodiments, various technical solutions known to those of ordinary skill in the art now and in the future can be adopted, which will not be described in detail here.

[0043] In the description of this specification, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to this application.

[0044] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of this application, "a plurality" means two or more unless otherwise specifically defined.

[0045] In this application, unless otherwise clearly specified and limited, the terms such as "installed", "connected", "connected to", "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0046] In this application, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0047] The foregoing disclosure provides many different embodiments or examples for implementing different structures of the present application. To simplify the disclosure of the present application, the components and settings of specific examples are described above. Of course, they are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0048] As described above, the foregoing are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present application can easily conceive of various changes or substitutions, and these should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An analytical gas recovery and reuse device for hydrogen production by methanol cracking, which is arranged behind the adsorption equipment for hydrogen production by methanol cracking, is characterized in that, The device comprises the following equipment connected in sequence: a first analytical gas buffer tank (4), a second analytical gas buffer tank (6) and an analytical gas compressor (8); The first analytical gas buffer tank (4) is connected to the adsorption device via a first pipeline, and a first program-controlled valve (1) is provided on the first pipeline; The second analytical gas buffer tank (6) is connected to the adsorption device via a second pipeline, and a second program-controlled valve (2) is provided on the second pipeline; A third desorption gas buffer tank (7) is also connected between the second desorption gas buffer tank (6) and the desorption gas compressor (8); A water washing tower (10) is connected after the analytical gas compressor (8); A first filter (3) is also provided between the first analytical gas buffer tank (4) and the first program-controlled valve (1); The following equipment is also connected between the analytical gas compressor (8) and the water washing tower (10): a second filter (9).

2. The analytical gas recovery and reuse device according to claim 1, wherein A pressure gauge is provided on the pipeline connecting the first filter (3) and the first analytical gas buffer tank (4).

3. The analytical gas recovery and reuse device according to any one of claims 1-2, characterized in that, Valves are provided between each device.

4. The analytical gas recovery and reuse device according to claim 3, characterized in that, The valves between the first analytical gas buffer tank (4) and the second analytical gas buffer tank (6) sequentially include a front stop valve, a pressure reducing valve (5) and a rear stop valve.

5. The analytical gas recovery and reuse device according to claim 1, characterized in that The volume of the first analytical gas buffer tank (4) is 75 - 85 m 3 , and the volume of the second analytical gas buffer tank (6) is 3 - 5 m 3 .

6. A hydrogen production and reforming gas recovery and reuse system for methanol cracking, characterized in that, A device for recovering and reusing the analytical gas comprising the device described in any one of claims 1 to 5.

7. A method for analyzing and recycling gas, characterized in that, The following steps are involved: (1) When the pressure of the gas to be analyzed is higher than 25 kPa, the analyzed gas is sequentially introduced into the first analyzed gas buffer tank (4) and the second analyzed gas buffer tank (6) according to any one of claims 1 to 5, and then flows to the analyzed gas compressor (8); (2) When the pressure of the analyzed gas drops to no more than 25 kPa, the analyzed gas is directly introduced into the second analyzed gas buffer tank (6) according to any one of claims 1 to 5 and then flows to the analyzed gas compressor (8).

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