Heat exchange assembly and fixed bed reactor
By designing convenient heat exchange components and fixed bed reactor structure, the problem of inconvenient catalyst loading and unloading in traditional reactors is solved, the construction efficiency is improved and the maintenance cost is reduced.
Patent Information
- Application Number
- CN202420881303.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-26
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2034-04-26
AI Technical Summary
The catalyst loading and unloading in traditional fixed-bed chemical reactors is inconvenient, resulting in low construction efficiency and high maintenance costs.
A heat exchange assembly including an upper distributor, a lower distributor and a heat exchange tube was designed. The catalyst was filled by a heat exchange tube between the upper and lower distributors, and the catalyst was easily loaded and unloaded and replaced by a semi-spherical seal and discharge port. .
It improves construction efficiency, reduces equipment maintenance costs, and realizes efficient and convenient loading, unloading and replacement of catalysts.
Smart Images
Figure CN222240182U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a chemical device, in particular to a heat exchange structure suitable for synthetic ammonia or synthetic methanol reaction and a corresponding fixed bed reactor, specifically a heat exchange component and a fixed bed reactor. Background Art
[0002] Fixed bed chemical reactor is one of the core equipment of chemical production, widely used in chemical industry, oil refining, metallurgy and other fields. The advanced level of its technology has an important impact on chemical production, directly affecting the investment scale and production cost of the device. Fixed bed reactor refers to a reactor filled with granular solid catalyst or solid reactant to form a stacked bed layer of a certain height. Gas or liquid materials flow through the static fixed bed layer through the gaps between particles to realize a heterogeneous reaction process. In many fixed bed chemical reaction processes, it is often accompanied by energy exchange, mainly in the form of heat absorption and heat release, that is, it is necessary to take away the heat generated by the reaction in time or bring in the heat required for the reaction in time.
[0003] At present, the tube-sheet heat exchanger is mainly installed in the reactor. This type of heat exchanger is composed of a plurality of vertical heat exchange tubes, both ends of which are connected to the plate-shaped tube sheets. Catalysts are filled between the tube sheets, and the outer side is a heat exchange medium channel, so that the heat exchange medium flows through the heat exchange tubes and exchanges heat with the reaction gas flowing through the catalyst, thereby taking away the heat generated by the catalytic reaction.
[0004] However, in a reactor using the above-mentioned heat exchange structure, since the catalyst needs to be loaded between the upper and lower tube sheets, when the catalyst needs to be replaced, the tube sheets often need to be removed, or the catalyst needs to be cleaned out using a vacuum cleaner, which makes the operation extremely inconvenient, affects the construction efficiency, and increases the maintenance cost.
[0005] Therefore, it needs to be improved to better meet production needs. Utility Model Content
[0006] The purpose of the utility model is to provide a heat exchange component and a fixed bed reactor to address the deficiencies of the prior art, which can effectively solve the problem of inconvenient loading and unloading of catalysts in the reactor, improve construction efficiency, and reduce equipment maintenance costs.
[0007] The technical solution of the utility model is:
[0008] A heat exchange component comprises an upper distributor, a lower distributor and a heat exchange tube, wherein the upper distributor and the lower distributor have the same structure and shape, and both comprise a main tube and a branch tube; the main tube is a straight tube with two open ends; the branch tube is a straight tube, one end of which is connected to the main tube, and the other end is a suspended end and is closed; there are a plurality of branch tubes, which are symmetrically arranged on both sides of the main tube and are in the same plane; the distance between the center of the end face of the suspended end of each branch tube and the center of the main tube is the same; the upper distributor and the lower distributor are arranged in parallel up and down; the heat exchange tube is a straight tube, arranged vertically, and its two ends are respectively connected to the branch tubes of the upper distributor and the lower distributor; there are a plurality of heat exchange tubes, which are arranged in a circular straight line.
[0009] Furthermore, the branch pipe is perpendicular to the main pipe.
[0010] Furthermore, the branch pipes are equidistant from each other.
[0011] Furthermore, the diameters of the main pipe and the branch pipe of the upper distributor are larger than those of the main pipe and the branch pipe of the lower distributor.
[0012] A fixed bed reactor comprises the heat exchange component; and also comprises a barrel; the barrel is a vertical cylindrical shape, and its upper and lower ends are open and respectively connected to an upper head and a lower head; the upper head is provided with an air inlet; the lower head is provided with an air outlet and a discharge port; the heat exchange component is arranged in the barrel; the two ends of the main pipe extend out of the barrel; a catalyst is arranged between the upper distributor and the lower distributor; and the lower head is filled with a heat storage body to the lower distributor.
[0013] Furthermore, the upper head and the lower head have the same structure, both of which are hemispherical shells with their openings facing the interior of the cylinder.
[0014] Furthermore, the air inlet and the air outlet are located at the center of the upper head and the lower head respectively.
[0015] Furthermore, the discharge port is arranged obliquely.
[0016] Furthermore, there are two discharge ports, which are symmetrically arranged on both sides of the air outlet.
[0017] Beneficial effects of the utility model:
[0018] The utility model has reasonable design, simple structure and is easy to use. By improving the structure of the heat exchange component, it effectively solves the inconvenience of traditional reactors in catalyst loading and unloading, improves construction efficiency, reduces equipment maintenance costs, and fully meets production needs. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1It is a structural schematic diagram of the heat exchange component of the utility model.
[0020] Figure 2 It is a structural schematic diagram of the fixed bed reactor of the utility model.
[0021] Among them, 1-upper distributor; 2-lower distributor; 3-heat exchange tube; 4-main pipe; 5-branch pipe; 6-cylinder; 7-catalyst; 8-lower head; 9-discharge port; 10-gas outlet; 11-heat storage body; 12-upper head; 13-gas inlet. DETAILED DESCRIPTION
[0022] The utility model is further described below in conjunction with the accompanying drawings and embodiments.
[0023] like Figure 1 As shown, the utility model provides a heat exchange component, comprising an upper distributor 1, a lower distributor 2 and a heat exchange tube 3.
[0024] The upper distributor 1 and the lower distributor 2 have the same structure and shape, and both include a main pipe 4 and a branch pipe 5. The main pipe 4 is a straight pipe with both ends open. The branch pipe 5 is a straight pipe, one end of which is connected to the main pipe 4, and the other end is a suspended end and is closed. There are multiple branch pipes 5, which are symmetrically arranged on both sides of the main pipe and in the same plane. At the same time, the distance between the end face center of the suspended end of each branch pipe 5 and the center of the main pipe 4 is the same, so that they are arranged in a slightly circular structure, which is convenient for subsequent installation.
[0025] The branch pipes 5 are perpendicular to the main pipe 4, and the branch pipes 5 are equidistantly distributed. Preferably, the spacing between the branch pipes is 10-30 mm.
[0026] The upper distributor 1 and the lower distributor 2 are arranged in parallel up and down. The heat exchange tube 3 is a straight tube, which is vertically arranged between the upper distributor 1 and the lower distributor 2, and its two ends are respectively connected to the branch pipes of the upper distributor 1 and the lower distributor 2. There are multiple heat exchange tubes 3, and they are arranged in a circular straight line.
[0027] like Figure 2 As shown, the utility model is a fixed bed reactor, comprising a cylinder 6.
[0028] The cylinder 6 is in the shape of a vertical cylinder, and its upper and lower ends are both open and connected to the upper head 12 and the lower head 8 respectively, so that the upper and lower ends of the cylinder 6 are closed.
[0029] The upper head 12 and the lower head 8 have the same structure, both of which are hemispherical shells, and their openings face the interior of the cylinder 6, which is conducive to the convergence of gas, liquid or granular solids.
[0030] The center of the upper end cap 12 is provided with an air inlet 13 for inputting reaction gas and catalyst etc. The center of the lower end cap 8 is provided with an air outlet 10 for the reaction gas to flow out.
[0031] The heat exchange assembly is arranged in the cylinder, and the two are matched so that the upper and lower distributors are respectively located at the upper and lower ends of the cylinder. At the same time, the two ends of the main pipe extend out of the cylinder and are connected to the external steam drum, so that the heating medium from the steam drum can flow through the heat exchange assembly from bottom to top. Preferably, the diameters of the main pipe and branch pipe of the upper distributor are larger than those of the main pipe and branch pipe of the lower distributor, so that the volume of the upper distributor is 105-130% of the volume of the lower distributor, so as to meet the requirements of phase change of the heat exchange medium due to heat absorption during the heat exchange process.
[0032] A catalyst 7 is provided between the upper distributor and the lower distributor, and the heat exchange tube 3 is buried in the catalyst 7. At the same time, a heat storage body 11 is filled in the lower head 8, and the top surface of the heat storage body 11 is located at the lower distributor, so as to support the catalyst 7. At the same time, a metal mesh structure is provided on the gas outlet 10 to prevent the heat storage body from falling out.
[0033] The lower end cap 8 is also provided with a discharge port 9 for discharging the heat storage body and the catalyst. The discharge port 9 is obliquely arranged, and the angle between its center line and the center line of the cylinder 6 is about 45°. At the same time, there are two or more discharge ports 9, which are symmetrically distributed with the gas outlet as the center, making the discharge more convenient.
[0034] The method of using the utility model is:
[0035] First, the heat storage body is poured into the reactor from the air inlet, so that it is filled in the lower head. The heat storage body includes but is not limited to aluminum oxide, mullite, etc., which is granular with a particle size of 1.5~2mm, and can smoothly pass through the upper and lower distributors and enter the lower head to form a support structure, which can support the catalyst bed and will not react chemically with the reaction gas.
[0036] After the heat storage body is filled, the catalyst is poured into the reactor through the air inlet. The catalyst is granular, with a particle size of about 2.5mm, and can smoothly pass through the gap between the upper distributor and the heat exchange tube, and is supported by the heat storage body at the lower distributor, so that it is filled between the upper and lower distributors to form a catalyst bed, and the heat exchange tube is buried in it.
[0037] Then, the main pipe port of the upper distributor is connected to the inlet of the external steam drum, and the main pipe port of the lower distributor is connected to the outlet of the steam drum, so that the heat exchange medium from the steam drum flows through the lower distributor, heat exchange tubes and upper distributor in sequence to achieve circulating flow.
[0038] During production, the reaction gas enters the reactor from the air inlet and flows downward through the catalyst bed to react. At the same time, the reaction heat is taken away through heat exchange with the heat exchange tube to keep the catalyst bed temperature stable. After the reaction, the gas flows through the heat storage body and flows out from the gas outlet to complete the production.
[0039] When the catalyst needs to be replaced, open the discharge port and discharge the heat storage body first. The catalyst in the catalyst layer loses the support of the heat storage body and falls into the lower head, and flows out through the discharge port, thus completing the removal of the catalyst. This is not only efficient and convenient, but also can make the removal complete and thorough, without the need to use additional tools such as vacuum cleaners.
[0040] The utility model improves the structure of the heat exchange component, effectively solves the problem of inconvenience in loading and unloading the catalyst in the traditional reactor, improves the construction efficiency, reduces the equipment maintenance cost, and fully meets the production needs.
[0041] 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 heat exchange assembly, comprising an upper distributor, a lower distributor and a heat exchange tube, characterized in that: The upper distributor and the lower distributor have the same structure and shape, and both include a main pipe and a branch pipe; the main pipe is a straight pipe with two open ends; the branch pipe is a straight pipe, one end of which is connected to the main pipe, and the other end is a suspended end and is closed; there are multiple branch pipes, which are symmetrically arranged on both sides of the main pipe and are in the same plane; the distance between the center of the end face of the suspended end of each branch pipe and the center of the main pipe is the same; the upper distributor and the lower distributor are arranged in parallel up and down; the heat exchange tube is a straight tube, arranged vertically, and its two ends are respectively connected to the branch pipes of the upper distributor and the lower distributor; there are multiple heat exchange tubes, which are arranged in a circular straight line.
2. The heat exchange assembly according to claim 1, characterized in that: The branch pipe is perpendicular to the main pipe.
3. The heat exchange assembly according to claim 1, characterized in that: The branch pipes are equidistant from each other.
4. The heat exchange assembly according to claim 1, characterized in that: The diameters of the main pipe and the branch pipe of the upper distributor are larger than those of the main pipe and the branch pipe of the lower distributor.
5. A fixed bed reactor, characterized in that: It includes the heat exchange component described in any one of claims 1-2; and also includes a cylinder; the cylinder is a vertical cylindrical shape, and its upper and lower ends are open and respectively connected to the upper head and the lower head; the upper head is provided with an air inlet; the lower head is provided with an air outlet and a discharge port; the heat exchange component is arranged in the cylinder; the two ends of the main pipe extend out of the cylinder; a catalyst is provided between the upper distributor and the lower distributor; the lower head is filled with a heat storage body to the lower distributor.
6. The fixed bed reactor according to claim 5, characterized in that: The upper head and the lower head have the same structure, both are hemispherical shells, and their openings face the inside of the cylinder.
7. The fixed bed reactor according to claim 5, characterized in that: The air inlet and the air outlet are located at the center of the upper head and the lower head respectively.
8. The fixed bed reactor according to claim 5, characterized in that: The discharge port is arranged obliquely.
9. The fixed bed reactor according to claim 5, characterized in that: There are two discharge ports, which are symmetrically arranged on both sides of the air outlet.