A gas purification and pretreatment device for dimethyl carbonate synthesis

Abstract

The utility model relates to a kind of gas purification pretreatment device for dimethyl carbonate synthesis, including processing tank, inlet valve pipe, pretreatment mechanism and exhaust pipe, the processing tank surface is connected with inlet valve pipe and exhaust pipe, the pretreatment mechanism is installed in processing tank, for by inlet valve pipe into the dimethyl carbonate synthesis gas preliminary purification of processing tank, dimethyl carbonate synthesis gas enters processing tank by inlet valve pipe, external purification liquid enters spray ring body by liquid supply pipe, atomized purification liquid is sprayed into processing tank, atomized purification liquid falling will repeatedly contact gas in processing tank, wherein control valve is equipped in liquid supply pipe, start driver drives stem body rotation, to control auger blade rotation, gas is sent upwards, for purification liquid sufficient contact, and auger blade is provided with hole portion, make part purification liquid seep through through-hole in ascending process, form liquid film droplet double contact mode, improve purification effect.

Description

Technical Field

[0001] This utility model relates to the technical field of gas purification equipment, specifically a gas purification and pretreatment device for the synthesis of dimethyl carbonate. Background Technology

[0002] Dimethyl carbonate (DMC), as a green chemical raw material, requires high-purity gases (such as carbon monoxide, oxygen, and methanol vapor) as raw materials for its synthesis processes (such as methanol oxidative carbonylation and transesterification). Impurities in the raw gas, such as sulfides, chlorides, dust, and moisture, can lead to catalyst poisoning, equipment corrosion, and decreased product purity. Therefore, impurities must be removed through gas purification and pretreatment devices.

[0003] Existing gas purification and pretreatment devices mostly adopt a structure combining a scrubbing tower and a spray system: the raw gas enters from the bottom of the tower and comes into countercurrent contact with the purification liquid sprayed from the top of the tower, such as alkaline solution or adsorbent solution, to remove impurities through absorption or adsorption. To improve purification efficiency, some devices will install packing material inside the tower to extend the gas-liquid contact path, but the following problems exist:

[0004] Limited gas-liquid contact efficiency: The fixed structure of traditional packing makes it easy for gas to form a "short-circuit flow". Some gas rises directly from the gaps between the packing without sufficient contact, resulting in a short actual contact path and difficulty in thoroughly purifying low-concentration impurities. At the same time, the purification liquid mostly flows down along the surface of the packing after spraying, resulting in insufficient uniformity of mixing with the gas. Therefore, we need to provide a gas purification pretreatment device for dimethyl carbonate synthesis. Utility Model Content

[0005] The purpose of this invention is to provide a gas purification and pretreatment device for the synthesis of dimethyl carbonate. The device has a pretreatment mechanism inside the treatment tank, which can spray atomized purification liquid from the top of the treatment tank through a spray nozzle. The gas entering the treatment tank is also lifted by the rotation of the auger blades, so that it can fully contact the atomized purification liquid, thereby improving the impurity absorption efficiency. This is especially beneficial for the deep purification of low-concentration harmful components, thus solving the problems mentioned in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a gas purification and pretreatment device for dimethyl carbonate synthesis, comprising:

[0007] The system includes a processing tank, an inlet valve pipe, a pretreatment mechanism, and an exhaust pipe. The surface of the processing tank is connected to the inlet valve pipe and the exhaust pipe. The pretreatment mechanism is installed inside the processing tank and is used for the preliminary purification of the gas used in the synthesis of dimethyl carbonate that enters the processing tank through the inlet valve pipe.

[0008] The pretreatment mechanism includes a rod, auger blades, and a spray component. The rod is rotatably installed inside the treatment tank, and the auger blades are fixedly installed on its surface. The spray component is installed inside the treatment tank and is used to spray the purified liquid into atomized spray of the purified gas.

[0009] Preferably, the spraying component includes a liquid supply pipe, a base, and a spraying ring. The base is movably sleeved on the surface of the rod and fixed inside the treatment tank by a bracket. The spraying ring is fixedly installed on the top of the base.

[0010] Preferably, the base is a conical base, and the external purification liquid enters the spray ring through the liquid supply pipe and is sprayed out from the nozzle on the surface of the spray ring.

[0011] Preferably, a receiving cylinder is threadedly installed at the bottom of the treatment tank, a filter screen is installed inside the receiving cylinder, and an agitator blade is fixedly installed at the lower end of the rod.

[0012] Preferably, after the receiving cylinder is installed at the bottom of the processing tank, the bottom of the stirring blade is infinitely close to the top of the filter screen, and a limiting ring for supporting the filter screen is fixedly installed on the inner wall of the receiving cylinder.

[0013] Preferably, the surface of the auger blade has multiple holes.

[0014] Preferably, the bottom of the processing tank is provided with a driver that drives the rod to rotate.

[0015] Preferably, the processing tank is provided with a support portion for auxiliary support of the rod.

[0016] Compared with the prior art, the beneficial effects of this utility model are:

[0017] This invention features a pretreatment mechanism within the treatment tank. Atomized purification liquid is sprayed from the top of the tank via a spray nozzle. The rotating auger blades draw the incoming gas upwards, ensuring full contact with the atomized purification liquid. A filter element at the exhaust pipe provides secondary filtration. The rotating auger blades create a spiral upward channel, significantly extending the gas's travel distance within the tank. Combined with the atomized purification liquid sprayed from the top nozzle, this significantly increases the gas-liquid contact time and area, improving impurity absorption efficiency. It is particularly beneficial for the deep purification of low-concentration harmful components. The channel guides the gas to flow uniformly, avoiding short-circuiting issues common in traditional devices, ensuring each gas component fully contacts the purification liquid and improving purification uniformity. The vortex effect created by the rotating auger blades enhances the dispersion of atomized droplets, reduces liquid film aggregation, and improves mass transfer efficiency. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural schematic diagram of the present invention;

[0019] Figure 2This is a front sectional view of the processing tank of this utility model;

[0020] Figure 3 This is a three-dimensional sectional view of the processing tank of this utility model;

[0021] Figure 4 This is a partial three-dimensional sectional view of the present invention;

[0022] Figure 5 This is a perspective view of the spray component of this utility model.

[0023] In the diagram: 1. Processing tank; 2. Inlet valve pipe; 3. Pre-treatment mechanism; 31. Rod body; 32. Screw blade; 33. Spray component; 331. Liquid supply pipe; 332. Base; 333. Spray ring body; 4. Exhaust pipe; 5. Receiving cylinder; 6. Filter screen; 7. Stirring blade; 8. Limiting ring; 9. Hole; 10. Driver. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Please see Figure 1-5 This utility model provides a technical solution: a gas purification and pretreatment device for dimethyl carbonate synthesis, comprising:

[0026] The treatment tank 1, the inlet valve pipe 2, the pretreatment mechanism 3 and the exhaust pipe 4 are connected on the surface of the treatment tank 1. The pretreatment mechanism 3 is installed in the treatment tank 1 and is used for the preliminary purification of the gas for dimethyl carbonate synthesis that enters the treatment tank 1 through the inlet valve pipe 2.

[0027] The pretreatment mechanism 3 includes a rod 31, an auger blade 32, and a spray component 33. The rod 31 is rotatably installed in the treatment tank 1, and the auger blade 32 is fixedly installed on its surface. The spray component 33 is installed in the treatment tank 1 and is used to spray the purified liquid of the purified gas into atomized spray.

[0028] Specifically, a pretreatment mechanism 3 is provided inside the treatment tank 1. Atomized purification liquid is sprayed from the top of the treatment tank 1 through the spray element 33. The gas entering the treatment tank 1 is raised by the rotation of the auger blades 32, which fully contacts the atomized purification liquid. A filter element is provided at the exhaust pipe 4 to achieve secondary filtration. The rotation of the auger blades 32 forms a spiral upward channel, which greatly extends the gas travel in the treatment tank 1. Combined with the atomized purification liquid sprayed by the top spray element 33, the gas-liquid contact time and contact area are significantly increased, improving the impurity absorption efficiency. It is especially beneficial for the deep purification of low-concentration harmful components. The channel can guide the gas to flow evenly, avoiding the gas short-circuit problem in traditional devices, so that each part of the gas can fully contact the purification liquid, improving the purification uniformity. The vortex effect formed by the rotation of the auger blades 32 can enhance the dispersion of atomized droplets, reduce liquid film aggregation, and improve mass transfer efficiency.

[0029] The spraying component 33 includes a liquid supply pipe 331, a base 332 and a spraying ring 333. The base 332 is movably sleeved on the surface of the rod 31 and fixed in the treatment tank 1 by a bracket. The spraying ring 333 is fixedly installed on the top of the base 332.

[0030] Furthermore, the spray ring 333 is made of 316L stainless steel, and the spray range overlaps and covers the surface of the auger blades 32, ensuring that the purified liquid is atomized and forms a ring-shaped surface on one side inside the treatment tank 1, thereby increasing the spray range.

[0031] The base 332 is set as a conical seat. The external purification liquid enters the spray ring 333 through the liquid supply pipe 331 and is sprayed out from the nozzle on the surface of the spray ring 333.

[0032] It should be noted that the cone angle of the cone seat is 60° and the surface is coated with polytetrafluoroethylene. When the gas passes through the surface of the cone seat, it will be dispersed by the cone seat into the atomized purification liquid, reducing interference with the gas rising path.

[0033] A receiving cylinder 5 is threadedly installed at the bottom of the processing tank 1, and a filter screen 6 is installed inside the receiving cylinder 5. An agitator blade 7 is fixedly installed at the lower end of the rod body 31.

[0034] It is worth noting that the stirring blade 7 is made of Hastelloy and has a straight structure. The edge of the blade can be provided with a 0.5mm thick elastic scraper. The gap between the scraper and the surface of the filter screen 6 can be controlled at 0.1-0.3mm by adjusting the screw depth of the receiving cylinder 5. When the stirring blade 7 rotates with the rod 31, the elastic scraper can remove the initial crystal layer on the surface of the filter screen 6 in real time, which solves the problem of poor drainage caused by crystal blockage of the filter screen 6 in traditional devices and extends the cleaning cycle of the filter screen 6.

[0035] After the receiving cylinder 5 is installed at the bottom of the processing tank 1, the bottom of the stirring blade 7 is infinitely close to the top of the filter screen 6, and a limiting ring 8 supporting the filter screen 6 is fixedly installed on the inner wall of the receiving cylinder 5.

[0036] It is worth noting that the bottom of the treatment tank 1 is provided with a receiving cylinder 5, and the contact cylinder is threadedly installed with the treatment tank 1, and a sealing ring is provided at the connection. The purified liquid is collected, and impurities or crystals are intercepted by the filter screen 6 inside the receiving cylinder 5. A stirring blade 7 is provided at the lower end of the rod 31, which can move the debris on the filter screen 6 to avoid clogging the filter screen 6. The filter screen 6 is snapped on the limiting ring 8, which can easily remove the filter screen 6.

[0037] The surface of the auger blade 32 has multiple holes 9;

[0038] Among them, the hole 9 is a waist-shaped hole with a diameter of 5-8mm, which is staggered along the spiral direction of the auger blade 32, and the edge of the hole is provided with an upwardly protruding guide edge; when the auger blade 32 rotates, part of the purified liquid falls through the waist-shaped hole to form droplets and makes reverse contact with the rising gas, while the guide edge can guide another part of the purified liquid to the blade surface to form a continuous liquid film, realizing dual mass transfer of droplets and liquid film.

[0039] The bottom of the processing tank 1 is equipped with a driver 10 that drives the rod body 31 to rotate.

[0040] The processing tank 1 is equipped with a support part that provides auxiliary support for the rod 31;

[0041] The support part consists of a support frame and a support ring. The support ring is fixed on the surface of the rod 31. The support frame is installed inside the treatment tank 1 and supports the support ring. A sealed bearing can be provided at the bottom of the support ring, which not only achieves radial positioning of the rod 31, but also transforms the traditional sliding friction into rolling friction, thereby reducing the rotational resistance of the rod 31 and avoiding the risk of sparks generated by metal-to-metal contact.

[0042] The filter element adopts a gradient composite structure, consisting of a stainless steel wire mesh layer (50μm pore size), an activated carbon fiber layer (5mm thickness), and a molecular sieve membrane layer (0.3nm pore size) from the outside to the inside. The three-stage filtration structure can sequentially intercept residual droplets, organic impurities, and trace amounts of moisture in the purified gas, reducing the total impurity content in the gas to below 0.05ppm, which meets the stringent requirements of the dimethyl carbonate synthesis catalyst for the feed gas.

[0043] The driver 10 involved in this application is a servo motor, which is implemented using existing mature technology and connected to an external PLC controller and power supply. This is a conventional technical means in this field, so its specific circuit connection, control logic and working process will not be described in detail.

[0044] In this device, the gas used for dimethyl carbonate synthesis enters the treatment tank 1 through the inlet valve pipe 2. External purified liquid enters the spray ring 333 through the supply pipe 331, atomizing the purified liquid and spraying it into the treatment tank 1. The atomized purified liquid falls and repeatedly contacts the gas inside the treatment tank 1. The supply pipe 331 is equipped with a control valve. Activating the driver 10 rotates the rod 31, thereby controlling the rotation of the auger blades 32, which transport the gas upwards for sufficient contact with the purified liquid. The auger blades 32 have holes 9, allowing some purified liquid to leak through the holes during its ascent, forming a double contact mode of liquid film and droplets, improving the purification effect. A receiving cylinder 5 is located at the bottom of the treatment tank 1, and the contact cylinder is positioned between the receiving cylinder and the treatment tank 1. The rod is threaded and has a sealing ring at the connection. The purified liquid is collected, and impurities or crystals are intercepted by the filter screen 6 inside the receiving cylinder 5. A stirring blade 7 is provided at the lower end of the rod 31 to move the debris on the filter screen 6 and prevent it from clogging. The filter screen 6 is snapped onto the limiting ring 8, which can be easily removed. The purified gas enters the filter element through the exhaust pipe 4 for secondary filtration. A sealing ring is provided at the connection between the rod 31 and the treatment tank 1, and a sealing ring is also provided at the connection between the air inlet valve pipe 2 and the treatment tank 1 to prevent gas from escaping from the treatment tank 1. The support part consists of a support frame and a support ring. The support ring is fixed to the surface of the rod 31, and the support frame is installed inside the treatment tank 1 and supports the support ring.

[0045] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A gas purification and pretreatment device for dimethyl carbonate synthesis, characterized in that, include: The treatment tank (1), the inlet valve pipe (2), the pretreatment mechanism (3) and the exhaust pipe (4) are connected on the surface of the treatment tank (1). The pretreatment mechanism (3) is installed inside the treatment tank (1) and is used for the preliminary purification of the gas for dimethyl carbonate synthesis that enters the treatment tank (1) through the inlet valve pipe (2). The pretreatment mechanism (3) includes a rod (31), an auger blade (32) and a spray component (33). The rod (31) is rotatably installed inside the treatment tank (1) and the auger blade (32) is fixedly installed on its surface. The spray component (33) is installed inside the treatment tank (1) and is used to spray the purified liquid of the purified gas into atomized spray.

2. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 1, characterized in that: The spraying component (33) includes a liquid supply pipe (331), a base (332) and a spraying ring (333). The base (332) is movably sleeved on the surface of the rod (31) and fixed inside the treatment tank (1) by a bracket. The spraying ring (333) is fixedly installed on the top of the base (332).

3. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 2, characterized in that: The base (332) is a conical base, and the external purification liquid enters the spray ring (333) through the liquid supply pipe (331) and is sprayed out from the nozzle on the surface of the spray ring (333).

4. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 1, characterized in that: The bottom of the treatment tank (1) is threaded with a receiving cylinder (5), a filter screen (6) is installed inside the receiving cylinder (5), and a stirring blade (7) is fixedly installed at the lower end of the rod (31).

5. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 4, characterized in that: After the receiving cylinder (5) is installed at the bottom of the processing tank (1), the bottom of the stirring blade (7) is infinitely close to the top of the filter screen (6), and a limiting ring (8) supporting the filter screen (6) is fixedly installed on the inner wall of the receiving cylinder (5).

6. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 1, characterized in that: The surface of the auger blade (32) is provided with multiple holes (9).

7. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 1, characterized in that: The bottom of the processing tank (1) is provided with a driver (10) that drives the rod (31) to rotate.

8. The gas purification and pretreatment device for dimethyl carbonate synthesis according to claim 1, characterized in that: The processing tank (1) is provided with a support part to provide auxiliary support for the rod (31).

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