Methylamine synthesis reaction heat exchanger

Abstract

The utility model discloses a methylamine synthesis reaction heat exchanger, which is characterized in that fixed partition plates are respectively arranged in an upper seal head and a lower seal head, and a plurality of groups of openings are formed in the fixed partition plates; a plurality of groups of inner tubes are vertically distributed in the shell, tube plates are respectively welded at the upper ends and the lower ends of the inner tubes, cavities are formed in the tube plates, and the cavities are respectively communicated with the inner tubes and the openings; the outer part of the inner pipe is coated with an outer pipe, and the end parts of the adjacent outer pipes are communicated through a connecting pipe. According to the device disclosed by the utility model, high-temperature reaction synthesis gas can be utilized to heat a mixture raw material to the greatest extent, energy recycling is fully realized, and meanwhile, reasonable cooling of the reaction synthesis gas can be realized, so that by arranging the heat exchanger, not only is the temperature of the mixture raw material increased, but also the effective cooling of the synthesis reactor is realized; and heat can be recycled, so that multiple purposes are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical industry, in particular to a methylamine synthesis reaction heat exchanger. Background Art

[0002] At present, methylamine is usually prepared by catalytic synthesis using methanol and liquid ammonia as raw materials to obtain crude methylamine. The crude methylamine then passes through a series of distillation processes such as a deamination tower, an extraction tower, a dehydration tower, and a separation tower to obtain monomethylamine, dimethylamine, and trimethylamine respectively.

[0003] In the aforementioned process of catalyzing the synthesis of crude methylamine from methanol and liquid ammonia, the reaction requires high reaction temperatures and generates significant heat. Prior to the reaction, the raw materials must be heated from ambient temperature to the desired reaction temperature. After the reaction, the product must be cooled from a high temperature to a low temperature before being fed into the subsequent distillation process.

[0004] The above-mentioned heating and cooling operations inevitably result in energy waste. To address this energy waste during the reaction, prior art generally utilizes multiple heat exchangers before the raw materials enter the synthesis tower, allowing for multiple heat exchanges to recycle the energy during the reaction and reduce energy consumption.

[0005] For example, the utility model patent with announcement number CN115193344A discloses a high-efficiency, energy-saving methylamine synthesis system and method. In this system, a liquid ammonia pump is connected to the low-temperature heat exchanger feed inlet via a liquid ammonia pipeline; a methanol pump is connected to the liquid ammonia pipeline via a first pipeline; a methanol pump is connected to the liquid-phase methanol inlet of the synthesis tower via a second pipeline; a methanol pump is connected to the material inlet of the methanol vaporizer via a third pipeline, and the methanol vaporizer is then connected to the vapor-phase methanol inlet of the synthesis tower via a vaporized methanol pipeline; the low-temperature heat exchanger is sequentially connected to the high-temperature heat exchanger feed inlet, the electric heating furnace feed inlet, and the synthesis tower mixed material inlet via pipelines; the synthesis tower discharge port is also connected to the methanol vaporizer heat source inlet and the high-temperature heat exchanger heat source inlet via pipelines, and the methanol vaporizer heat source outlet and the high-temperature heat exchanger heat source outlet are connected to the low-temperature heat exchanger heat source inlet via heat source pipelines. This patent allows for the reuse of energy from the reaction, but requires the configuration of multiple low-temperature and high-temperature heat exchangers, resulting in a large number of devices and complex piping connections. Utility Model Content

[0006] In order to solve the problems mentioned in the above background technology, the utility model provides a methylamine synthesis reaction heat exchanger.

[0007] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A methylamine synthesis reaction heat exchanger, wherein the upper head and the lower head are respectively provided with fixed partitions, and the fixed partitions are provided with multiple groups of openings;

[0009] Multiple groups of inner tubes are vertically distributed in the shell, and tube sheets are welded to the upper and lower ends of the inner tubes respectively. The tube sheets are provided with cavities inside, and the cavities are respectively connected to the inner tubes and the open port;

[0010] The outer tube is covered with an outer tube, and the ends of adjacent outer tubes are connected by connecting tubes. The bottom side of the outer tube is connected to the mixed raw material inlet pipe, and the top side is connected to the mixed raw material outlet pipe;

[0011] The upper head and the fixed partition are an integrally formed structure, and the lower head and the fixed partition are an integrally formed structure.

[0012] Preferably, the top of the upper head is connected to a reaction synthesis gas inlet pipe; the bottom of the lower head is connected to a reaction synthesis gas outlet pipe.

[0013] Preferably, the inner diameter of the opening gradually increases from an end close to the inner tube to an end far away from the inner tube.

[0014] Preferably, a bottom side of the shell is connected to a cold and hot medium inlet, and an upper side is connected to a cold and hot medium outlet.

[0015] Preferably, the shell is filled with cold and hot media, and the cold and hot media enter the heat exchanger through the cold and hot media inlet.

[0016] Preferably, the inner tube and the outer tube are fixed by baffles, and the baffles are fixed on both sides of the inner wall of the shell and are staggered so that the flow of the cold and hot media is in an "S" shape.

[0017] Preferably, the upper and lower ends of the outer tube are both closed.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] The utility model can maximize the use of high-temperature reaction synthesis gas to heat the mixed raw materials, fully realize the recovery and utilization of energy, and at the same time realize the reasonable cooling of the reaction synthesis gas. Therefore, through the setting of the heat exchanger in the utility model, it is possible to achieve both the heating of the mixed raw materials and the effective cooling of the synthesis reactor, and the recovery and utilization of heat, achieving multiple goals at one stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 This is a schematic diagram of the connection structure of the heat exchanger of the utility model;

[0022] Figure 2 This is a schematic diagram of the internal structure of the heat exchanger of the utility model;

[0023] Figure 3 This is a schematic diagram of the installation structure of the lower head of the utility model;

[0024] Figure 4 This is a schematic diagram of the installation structure of the outer tube of the utility model.

[0025] In the figure: shell 4, upper head 41, lower head 42, mixed raw material inlet pipe 43, mixed raw material outlet pipe 44, reaction synthesis gas outlet pipe 45, reaction synthesis gas inlet pipe 46, cold and hot medium inlet 47, cold and hot medium outlet 48, fixed partition 49, open port 410, inner tube 411, outer tube 412, baffle 413, connecting pipe 414, tube sheet 415. DETAILED DESCRIPTION

[0026] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, 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 embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Reference Figure 1-4 The methylamine synthesis reaction heat exchanger includes a shell 4, an upper head 41 and a lower head 42. The upper head 41 and the lower head 42 are respectively provided with a fixed partition 49. The fixed partition 49 is provided with multiple groups of openings 410. The inner diameter of the opening 410 gradually increases from the end close to the inner tube 411 to the end away from the inner tube 411.

[0028] Multiple groups of inner tubes 411 are vertically distributed in the shell 4, and tube sheets 415 are welded to the upper and lower ends of the inner tube 411 respectively. A cavity is provided inside the tube sheet 415, and the cavity is connected to the inner tube 411 and the opening 410 respectively. The upper and lower ends of the outer tube 412 are both closed to prevent leakage of the mixed raw material when entering the outer tube 412 through the mixed raw material inlet pipe 43. The mixed raw material enters the outer tube 412 through the mixed raw material inlet pipe 43, and the reaction synthesis gas enters the upper head 41 through the reaction synthesis gas inlet pipe 46, and then enters the inner tube 411 through the opening 410, thereby achieving heating of the mixed raw material, achieving efficient heat exchange effect, and realizing energy recycling.

[0029] The upper head 41 and the fixed partition 49 are an integrally formed structure; the lower head 42 and the fixed partition 49 are an integrally formed structure, which can avoid gas leakage problems and maximize the guarantee that the reaction synthesis gas enters the inner tube 411 smoothly.

[0030] The bottom side of the shell 4 is connected to a cold and hot medium inlet 47, and the upper side is connected to a cold and hot medium outlet 48. The inner tube 411 and the outer tube 412 are fixed by a baffle 413. The baffles 413 are fixed on both sides of the inner wall of the shell 4 and are staggered so that the flow of the cold and hot medium is in an "S" shape. It can be adjusted to a cold medium or a hot medium according to the actual temperature. After entering through the cold and hot medium inlet 47, it is discharged from the cold and hot medium outlet 48 and recycled, which can maximize the protection of energy loss in the heat exchanger.

[0031] The mixed raw material enters through the mixed raw material inlet pipe 43, and then enters the outer pipe 412 through the tube plate 415. At this time, the high-temperature reaction synthesis gas enters the upper head 41 through the reaction synthesis gas inlet pipe 46, and then enters the inner pipe 411 through the opening 410, so that the inner pipe 411 heats the mixed raw material in the outer pipe 412, while the high-temperature reaction synthesis gas is cooled, and the reverse heat exchange between the mixed raw material and the synthesis gas is completed, which not only realizes the heating of the mixed raw material, but also realizes the effective cooling of the synthesis reactor and can also recycle and utilize heat, achieving multiple goals at one stroke.

[0032] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation to the present invention.

[0033] In this utility model, unless otherwise expressly specified or limited, terms such as "disposed," "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; they may refer to mechanical connection, direct connection, or indirect connection through an intermediate medium; they may refer to internal communication between two elements or interaction between two elements. Those skilled in the art will be able to understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0034] The above is only a preferred specific implementation method of the present invention, but the protection scope of the present invention is not limited to this. Any technician familiar with the technical field within the technical scope disclosed by the present invention can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A methylamine synthesis reaction heat exchanger, comprising a shell (4), an upper head (41) and a lower head (42), characterized in that: The upper head (41) and the lower head (42) are respectively provided with fixed partitions (49), and the fixed partitions (49) are provided with multiple groups of openings (410); Multiple groups of inner tubes (411) are vertically distributed in the shell (4), and tube sheets (415) are welded to the upper and lower ends of the inner tubes (411). The tube sheets (415) are provided with cavities inside, and the cavities are respectively communicated with the inner tubes (411) and the open port (410); The outer tube (412) is coated on the outside of the inner tube (411), and the ends of adjacent outer tubes (412) are connected via a connecting tube (414). The bottom side of the outer tube (412) is connected to a mixed raw material inlet tube (43), and the top side is connected to a mixed raw material outlet tube (44). The upper sealing head (41) and the fixed partition (49) are an integrally formed structure, and the lower sealing head (42) and the fixed partition (49) are an integrally formed structure.

2. A methylamine synthesis reaction heat exchanger according to claim 1, characterized in that: The top of the upper end cap (41) is connected to a reaction synthesis gas inlet pipe (46); and the bottom of the lower end cap (42) is connected to a reaction synthesis gas outlet pipe (45).

3. A methylamine synthesis reaction heat exchanger according to claim 1, characterized in that: The inner diameter of the opening (410) gradually increases from an end close to the inner tube (411) to an end away from the inner tube (411).

4. A methylamine synthesis reaction heat exchanger according to claim 1, characterized in that: The bottom side of the shell (4) is connected to a cold and hot medium inlet (47), and the upper side is connected to a cold and hot medium outlet (48).

5. A methylamine synthesis reaction heat exchanger according to claim 1, characterized in that: The inner tube (411) and the outer tube (412) are fixed by a baffle (413). The baffles (413) are fixed to both sides of the inner wall of the shell (4) and are staggered so that the flow of the cold and hot media is in an "S" shape.

6. A methylamine synthesis reaction heat exchanger according to claim 1, characterized in that: The upper and lower ends of the outer tube are both closed.

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