Preheating type radial methanol synthesis reactor

Abstract

The utility model relates to a preheating type radial methanol synthesis reactor which comprises a barrel body, the barrel body is in a vertical cylindrical shape, the upper end and the lower end of the barrel body are respectively connected with an upper sealing head and a lower sealing head, the side wall of the barrel body is hollow, a plurality of air holes are formed in the inner wall of the barrel body, and a catalyst is arranged in the barrel body; the shell wall of the upper sealing head is hollow and is communicated with the side wall of the cylinder body; a reaction gas outlet communicated with the inner cavity of the shell wall of the upper sealing head is formed in the upper sealing head; the lower sealing head is filled with heat accumulators, and a discharge port and a gas collecting pipe are arranged on the shell wall of the lower sealing head; the heat exchange structure is arranged in the barrel body, and a heat exchange medium can flow through the heat exchange structure to exchange heat with reaction gas; the central pipe is arranged in the barrel, the upper end of the central pipe is closed, the lower end of the central pipe is open, and a through hole is formed in the side wall of the central pipe; and the gas distributor is arranged in the lower sealing head and is communicated with the lower end of the central pipe and the gas inlet pipe at the same time. According to the utility model, the problem that the catalyst is inconvenient to unload is solved.

Description

Technical Field

[0001] The utility model relates to a chemical plant, in particular to a methanol synthesis reactor, specifically a preheating radial methanol synthesis reactor. Background Art

[0002] In the chemical industry, methanol, as an important chemical raw material, has a wide range of application value and plays an important role in the fields of medicine, organic synthesis, coatings, etc. Synthetic methanol has become an important industry in the chemical industry due to its low production cost and wide range of uses. Its working principle is to generate methanol by synthesizing carbon monoxide, carbon dioxide and hydrogen under high pressure and low temperature conditions.

[0003] At present, the most widely used synthetic methanol process with large production capacity in the market is the radial methanol synthesis reactor, which is equipped with a catalyst bed and a heat exchange device. The heat exchange device is mostly a tube-sheet heat exchanger, which is composed of a plurality of vertical heat exchange tubes, the upper and lower ends of which are respectively connected to the plate-shaped tube sheet, and the catalyst is filled between the tube sheet and the heat exchange tube. The reaction gas flows radially through the catalyst bed and reacts chemically with the catalyst. At the same time, the heat generated in the reaction is taken away by the heat exchange device to ensure that the reaction continues.

[0004] However, this type of reactor has the following problems:

[0005] Inconvenient catalyst unloading: The catalyst needs to be unloaded from the lower tube plate, which makes the operation inconvenient and easily causes problems such as incomplete catalyst removal, affecting operational efficiency and increasing maintenance costs.

[0006] The low inlet temperature of the reaction gas leads to an increase in side reactions between the reaction gas and the catalyst, thus reducing the chemical reaction efficiency of the reactor.

[0007] Therefore, it needs to be improved to better meet the market demand. Utility Model Content

[0008] The purpose of the utility model is to provide a preheating radial methanol synthesis reactor to address the deficiencies of the prior art, which can effectively solve the problem of inconvenient catalyst unloading, increase the inlet temperature of the reaction gas, reduce the side reactions between the reaction gas and the catalyst, and improve the chemical reaction efficiency of the reactor.

[0009] The technical solution of the utility model is:

[0010] A preheating radial methanol synthesis reactor comprises a cylinder, wherein the cylinder is a vertical cylindrical body with two ends open, the side wall of the cylinder is hollow, and the inner wall of the cylinder is provided with a plurality of air holes that are connected with the inner cavity of the side wall; a catalyst is provided inside the cylinder;

[0011] It also includes an upper end cap and a lower end cap, which are respectively connected to the upper and lower ends of the cylinder; the shell wall of the upper end cap is hollow and connected to the side wall of the cylinder; the upper end cap is provided with a reaction gas outlet connected to the inner cavity of its shell wall; the lower end cap is filled with a heat storage body to support the catalyst; the lower end cap is provided with a discharge port and an air inlet pipe that are connected inside and outside;

[0012] It also includes a heat exchange structure, which is arranged in the cylinder and can allow the heat exchange medium to flow through it to exchange heat with the reaction gas;

[0013] It also includes a central tube, which is arranged in the cylinder, has a closed upper end, an open lower end, and a plurality of through holes extending from the inside to the outside on the side wall;

[0014] It also includes a gas distributor, which is arranged in the lower head and is connected to the lower end of the central pipe and the air inlet pipe at the same time.

[0015] Furthermore, the upper head and the lower head are both dome-shaped, with their openings facing the interior of the cylinder.

[0016] Furthermore, the upper cover is provided with a manhole communicating with the interior thereof.

[0017] Furthermore, the gas distributor includes an outer tube, an inner tube and a connecting tube; the outer tube is a circular ring tube; the inner tube is a short straight tube, concentrically arranged within the ring of the outer tube, its upper end is connected to the lower end of the center tube, and its lower end is closed; the connecting tube is a straight tube, and its two ends are respectively connected to the outer tube and the inner tube; the air inlet pipe is a straight tube, passed through the lower head, and its inner end is connected to the outer tube.

[0018] Furthermore, a static mixer is provided in the connecting pipe.

[0019] Furthermore, the heat exchange structure includes an upper distribution head, a lower distribution head and a heat exchange tube; the upper and lower distribution heads have the same structure, both including a central ring tube, a main tube and a branch tube; the central ring tube is in the shape of a circular ring; the main tube is in the shape of a straight tube, disposed on the outer side of the central ring tube, one end of which is connected to the central ring tube, and the other end is a suspended end; there are two main tubes, which are symmetrically arranged; the branch tube is in the shape of a straight tube, one end of which is connected to the main tube or the central ring tube, and the other end is suspended and closed; there are multiple branch tubes, which are evenly distributed on both sides of the main tube; the central ring tube, the main tube and the branch tube are in the same plane; the upper and lower distribution heads are respectively disposed at the upper and lower ends of the cylinder, and the suspended end of the main tube is extended out of the cylinder and connected to the external heat exchange circulation pipeline; there are multiple heat exchange tubes, all of which are in the shape of straight tubes, evenly distributed, and their two ends are respectively connected to the upper and lower distribution heads.

[0020] Furthermore, the branch pipe is perpendicular to the main pipe; and the distances from the closed ends of the branch pipes to the center of the central ring pipe are the same.

[0021] Furthermore, the diameters of the central ring pipe, the main pipe and the branch pipe of the upper distribution head are respectively larger than the diameters of the central ring pipe, the main pipe and the branch pipe of the lower distribution head.

[0022] Furthermore, the central tube is centrally arranged in the cylinder, and the lower end thereof passes through the middle hole of the central ring tube of the lower distribution head and is connected to the inner tube.

[0023] Furthermore, the reaction gas outlet is centrally arranged on the upper head; and the discharge port is centrally arranged on the lower head.

[0024] Beneficial effects of the utility model:

[0025] The utility model has a reasonable design and a simple structure. By filling the heat storage body in the lower head, the catalyst layer is supported to ensure the normal progress of the catalytic reaction. During maintenance, the heat storage body can be removed from the discharge port on the lower head first, and then the catalyst can be easily removed, which greatly facilitates the maintenance operation, improves the construction efficiency, and reduces the maintenance cost. At the same time, by setting a gas distributor, the waste heat in the reactor is fully utilized, so that the reaction gas can be effectively preheated before entering the catalyst bed, effectively solving the problem of low reaction gas temperature, reducing the side reaction between the reaction gas and the catalyst, and improving the chemical reaction efficiency of the reactor, which fully meets the production needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a structural schematic diagram of the utility model.

[0027] Figure 2 It is a top view of the heat exchange structure of the present utility model.

[0028] Figure 3 It is a structural schematic diagram of the gas distributor of the utility model.

[0029] Among them, 1-manhole; 2-upper head; 3-cylinder; 4-heat exchange tube; 5-center tube; 6-catalyst; 7-lower distribution head; 8-air inlet pipe; 9-heat storage body; 10-discharge port; 11-lower head; 12-gas distributor; 12-1-outer tube; 12-2-connecting tube; 12-3-inner tube; 12-4-static mixer; 13-upper distribution head; 14-reaction gas inlet; 15-main pipe; 16-branch pipe; 17-center ring pipe. DETAILED DESCRIPTION

[0030] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0031] like Figures 1 to 3 shown.

[0032] The utility model discloses a preheating type radial methanol synthesis reactor, which comprises a cylinder 3, a heat exchange structure, a gas distributor 12, a central tube 5, an air inlet tube 8 and the like.

[0033] The cylinder 3 is a vertical cylindrical shape, with its upper and lower ends both open and connected to the upper head 2 and the lower head 11 respectively, forming a closed structure. The side wall of the cylinder 3 is hollow, and a plurality of air holes are provided on its inner wall, which are connected to the inner cavity of the side wall. The air holes are evenly arranged in a triangular shape, and the aperture is 3-40 mm.

[0034] The upper head 2 and the lower head 11 are both dome-shaped, and their openings face the interior of the cylinder 3 to facilitate the gathering of gas.

[0035] The shell wall of the upper end cap 2 is hollow and connected to the side wall of the cylinder 3. At the same time, the upper end cap 2 is provided with a reaction gas outlet 14 connected to the inner cavity of its shell wall for the gas after the reaction to be discharged. Furthermore, the upper end cap 2 is also provided with a manhole 1 that penetrates inside and outside, so that the operator can enter the upper end cap to perform operations such as loading catalysts and equipment maintenance.

[0036] The heat exchange structure includes an upper distribution head 13, a lower distribution head 7 and a heat exchange tube 4, which is arranged in the cylinder 3 and enables the heat exchange medium to flow therethrough to exchange heat with the reaction gas.

[0037] The upper and lower distribution heads have the same structure, and both include a central ring pipe 17 , a main pipe 15 and a branch pipe 16 .

[0038] The central ring tube 17 is in a circular shape and is located in the center.

[0039] The main pipe 15 is a straight pipe, arranged outside the central ring pipe 17, one end of which is connected to the central ring pipe 17, and the other end of which is a suspended end. There are two main pipes 15, which are symmetrically arranged.

[0040] The branch pipe 16 is a straight pipe, one end of which is connected to the main pipe 15 or the central ring pipe 17, and the other end is suspended and closed. There are multiple branch pipes 16, which are evenly distributed on both sides of the main pipe 15. The central ring pipe 17, the main pipe 15 and the branch pipe 16 are in the same plane. At the same time, the branch pipe 16 is perpendicular to the main pipe 15, and the distance from its closed end to the center of the central ring pipe 17 is the same.

[0041] The upper and lower distribution heads are respectively arranged at the upper and lower ends of the cylinder 3, and the suspended end of the main pipe is extended out of the cylinder 3 so as to be connected with the external heat exchange circulation pipeline.

[0042] The heat exchange tubes 4 are multiple and straight tube-shaped and evenly distributed in the cylinder 3. Both ends of the heat exchange tubes 4 are respectively connected to the central ring tube, the main tube and the branch tube of the upper and lower distribution heads to form a flow passage for the heat exchange medium.

[0043] The heat exchange medium is saturated water. At the same time, the diameters of the central annular tube, main tube and branch tube of the upper distribution head 13 are respectively larger than the diameters of the central annular tube, main tube and branch tube of the lower distribution head 7, so as to meet the volume change requirement of saturated water after heating. Preferably, the inner diameter of the main tube of the upper distribution head 13 is 105-130% of the inner diameter of the main tube of the lower distribution head. The inner diameter of the central annular tube of the upper distribution head is 105-115% of the inner diameter of the central annular tube of the lower distribution head. The inner diameter of the branch tube of the upper distribution head is 105-115% of the inner diameter of the branch tube of the lower distribution head.

[0044] The central tube 5 is a long straight tube with an inner diameter of 100-500 mm and an outer diameter slightly smaller than the aperture of the central annular tube of the lower distribution head 7. The central tube 5 is centrally arranged in the cylinder 3, with its upper end being closed and adjacent to the central annular tube of the upper distribution head 13, and its lower end being open and slightly passing through the middle hole of the central annular tube of the lower distribution head 7. The side wall of the central tube 5 is provided with a plurality of through holes that penetrate inside and outside. The through holes are evenly arranged in a triangular shape, and the aperture is 2-30 mm.

[0045] The gas distributor 12 includes an outer tube 12-1, an inner tube 12-3 and a connecting tube 12-2. The outer tube 12-1 is a circular ring tube. The inner tube 12-3 is a short straight tube, which is concentrically arranged in the ring of the outer tube 12-1, with an open upper end and a closed lower end. The connecting tube 12-2 is a straight tube, and its two ends are respectively connected to the outer tube 12-1 and the inner tube 12-3, and a static mixer 12-4 is arranged therein. The static mixer 12-4 is a conventionally purchased product, which is composed of a series of short sheet elements twisted 180° left and right, so that the gas flowing through can be uniformly radially mixed through repeated segmentation and rotation in forward and reverse directions.

[0046] The gas distributor 12 is disposed in the lower end cap 11, and the upper end of the inner tube 12-3 is connected to the lower end of the central tube 5. The gas inlet pipe 8 is a short straight pipe, which is passed through the lower end cap 11, and the inner end thereof is connected to the outer tube 12-1, and the outer end thereof is connected to the reaction gas input pipe.

[0047] The cylinder 3 is provided with a catalyst 6, and the heat exchange tube 4 and the central tube 5 are immersed in the catalyst 6. At the same time, the lower end cap 11 is filled with a heat storage body 9, which can support the catalyst 6 and form a bed structure of the catalyst. The heat storage body 9 can be aluminum oxide, mullite, etc., which only plays a supporting role and does not react chemically with the reaction gas.

[0048] A discharge port 10 that penetrates inside and outside is centrally arranged on the shell wall of the lower head 11 .

[0049] The working process of the utility model is:

[0050] First, the heat storage body is loaded through the manhole, the heat storage body fills up the lower head, and the gas distributor is immersed in the heat storage body.

[0051] Then, the catalyst is loaded through the manhole so that the catalyst fills the inner space of the cylinder under the support of the heat storage body, and the heat exchange tube and the central tube are completely immersed in the catalyst.

[0052] At the same time, the outer ends of the main pipes of the upper and lower distribution heads are connected to the external heat exchange circulation system, so that the saturated water flows through the lower distribution head, the heat exchange pipe and the upper distribution head in sequence to exchange heat with the gas in the cylinder.

[0053] During production, the reaction gas is input from the air inlet pipe. When it flows through the gas distributor, it exchanges heat with the heat storage body to increase its temperature. After flowing into the central tube, it flows into the cylinder from the through hole to react with the catalyst. The static mixer in the gas distributor can make the reaction gas flowing through fully radially mixed, enhancing the heat exchange effect. At the same time, the heat generated during the reaction is taken away by heat exchange with the saturated water in the heat exchange tube, so that the temperature in the catalyst bed is in a suitable state. After absorbing heat, the saturated water partially vaporizes to form a steam-water mixture. After the water vapor is removed by the gas-liquid separator in the heat exchange circulation system, it flows back to the heat exchange tube to realize the circulation operation.

[0054] The reacted gas flows into the inner cavity of the cylinder side wall from the air hole, then flows out from the reaction gas outlet after passing through the inner cavity of the upper head shell wall, and enters the next process.

[0055] When the catalyst needs to be replaced or repaired, the discharge port can be opened to discharge the heat storage body first. Then, the catalyst falls due to the loss of support and is discharged from the discharge port, which greatly facilitates the catalyst unloading operation, improves the operating efficiency, and reduces the maintenance cost.

[0056] The utility model not only effectively solves the problem of inconvenient catalyst replacement that existed in the past, but also, by arranging a gas distributor, makes full use of the waste heat in the reactor, so that the reaction gas can be effectively preheated before entering the catalyst bed, reduces the side reaction between the reaction gas and the catalyst, improves the chemical reaction efficiency of the reactor, and fully meets the production needs.

[0057] The parts not involved in the present invention are the same as the prior art or can be implemented by using the prior art.

Claims

1. A preheating radial methanol synthesis reactor, comprising a cylinder, characterized in that: The cylinder is in the shape of a vertical cylinder with two open ends, a hollow side wall, and a plurality of air holes that are connected to the inner cavity of the side wall are arranged on the inner wall; a catalyst is arranged inside the cylinder; It also includes an upper end cap and a lower end cap, which are respectively connected to the upper and lower ends of the cylinder; the shell wall of the upper end cap is hollow and connected to the side wall of the cylinder; the upper end cap is provided with a reaction gas outlet connected to the inner cavity of its shell wall; the lower end cap is filled with a heat storage body to support the catalyst; the lower end cap is provided with a discharge port and an air inlet pipe that are connected inside and outside; It also includes a heat exchange structure, which is arranged in the cylinder and can allow the heat exchange medium to flow through it to exchange heat with the reaction gas; It also includes a central tube, which is arranged in the cylinder, has a closed upper end, an open lower end, and a plurality of through holes extending from the inside to the outside on the side wall; It also includes a gas distributor, which is arranged in the lower head and is connected to the lower end of the central pipe and the air inlet pipe at the same time.

2. The preheating radial methanol synthesis reactor according to claim 1, characterized in that: The upper head and the lower head are both in a dome-shaped shell shape, and their openings face the interior of the cylinder.

3. The preheating radial methanol synthesis reactor according to claim 1, characterized in that: The upper cover is provided with a manhole which is connected with the interior thereof.

4. The preheating radial methanol synthesis reactor according to claim 1 is characterized in that: The gas distributor includes an outer tube, an inner tube and a connecting tube; the outer tube is a circular ring tube; the inner tube is a short straight tube, which is concentrically arranged within the ring of the outer tube, its upper end is connected with the lower end of the center tube, and its lower end is closed; the connecting tube is a straight tube, and its two ends are respectively connected with the outer tube and the inner tube; the air inlet pipe is a straight tube, which is passed through the lower head, and its inner end is connected with the outer tube.

5. The preheating radial methanol synthesis reactor according to claim 4 is characterized in that: A static mixer is arranged in the connecting pipe.

6. The preheating radial methanol synthesis reactor according to claim 4, characterized in that: The heat exchange structure includes an upper distribution head, a lower distribution head and a heat exchange tube; the upper and lower distribution heads have the same structure, both including a central ring tube, a main tube and a branch tube; the central ring tube is in the shape of a circular ring; the main tube is in the shape of a straight tube, arranged on the outside of the central ring tube, one end of which is connected to the central ring tube, and the other end is a suspended end; there are two main tubes, which are symmetrically arranged; the branch tube is in the shape of a straight tube, one end of which is connected to the main tube or the central ring tube, and the other end is suspended and closed; there are multiple branch tubes, which are evenly distributed on both sides of the main tube; the central ring tube, the main tube and the branch tube are in the same plane; the upper and lower distribution heads are respectively arranged at the upper and lower ends of the cylinder, and the suspended end of the main tube is extended out of the cylinder and connected to the external heat exchange circulation pipeline; there are multiple heat exchange tubes, all of which are in the shape of straight tubes and evenly distributed, and their two ends are respectively connected to the upper and lower distribution heads.

7. The preheating radial methanol synthesis reactor according to claim 6 is characterized in that: The branch pipe is perpendicular to the main pipe; the distances from the closed ends of the branch pipes to the center of the central ring pipe are the same.

8. The preheating radial methanol synthesis reactor according to claim 6, characterized in that: The diameters of the central ring pipe, the main pipe and the branch pipe of the upper distribution head are respectively larger than the diameters of the central ring pipe, the main pipe and the branch pipe of the lower distribution head.

9. The preheating radial methanol synthesis reactor according to claim 6, characterized in that: The central tube is centrally arranged in the cylinder, and the lower end thereof passes through the middle hole of the central ring tube of the lower distribution head and is connected with the inner tube.

10. The preheating radial methanol synthesis reactor according to claim 1, characterized in that: The reaction gas outlet is centrally arranged on the upper end cover; the discharge port is centrally arranged on the lower end cover.

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