Zero-leakage vertical acid condenser

Abstract

The zero-leakage vertical acid condenser comprises an upper tube box, a lower tube box and a vertical tube shell heat exchange assembly, the vertical tube shell heat exchange assembly comprises a shell, an upper tube plate, a lower tube plate, a glass heat exchange tube and a baffle plate, and an air inlet and an air outlet are formed in the upper portion and the lower portion of the shell respectively. The upper tube box and the lower tube box are respectively provided with a flue gas outlet and a flue gas inlet, and the bottom of the lower tube box is provided with an acid discharge port. According to the acid condenser, high-temperature process gas enters the acid cooler from the side face of the bottom, the rectifying wall is arranged at the bottom, the process gas evenly enters all the glass tubes, the breakage probability of the glass tubes is reduced, and the heat exchange performance of the whole heat exchanger is improved. The upper tube plate and the glass heat exchange tube in the acid condenser adopt a zero-leakage sealing form, and the lower tube plate adopts a zero-leakage sealing form, so that zero leakage of the acid condenser can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchange equipment, and in particular to a zero-leakage vertical acid condenser. Background Art

[0002] Hydrogen sulfide is produced in the production processes of natural gas purification, petroleum refining, coal gas, leather, pharmaceuticals, papermaking, synthetic chemical fibers, etc. It is one of the main air pollutants, which not only harms human health, but also seriously corrodes equipment. Therefore, it is necessary to treat and utilize the acidic gas containing hydrogen sulfide, which is not only a need for comprehensive resource utilization, but also a requirement for environmental protection.

[0003] The process flow of wet acid making process (WSA process) is as follows: acid gas, coal gas and heated air are sent into the incinerator for combustion. 2 S is burned to generate SO 2 , SO 2 SO is produced by catalytic oxidation of WSA catalyst 3 , SO 3 It reacts with water to generate sulfuric acid, which is then condensed into liquid sulfuric acid by the WSA condenser, containing trace amounts of SO 2 The tail gas containing acid mist is discharged through the chimney after being treated to meet the standards.

[0004] The working principle of WSA condenser is based on the principle of heat energy transfer and phase change. 3 When sulfuric acid (and water vapor) flows through the WSA condenser, these gases first react with water vapor to form sulfuric acid vapor, which is then cooled by the external room temperature air in the condenser to condense into sulfuric acid liquid. During this process, a large number of vertical glass tubes are installed inside the WSA condenser. These glass tubes are both corrosion-resistant and shock-resistant, and can effectively promote the condensation of sulfuric acid vapor. For example, the sulfuric acid condenser described in references 1 and 2:

[0005] Reference 1: Chinese patent document with publication number CN206793088U

[0006] Reference 1 records a sulfuric acid vapor condenser for wet sulfuric acid production, which includes a lower acid tank, an intermediate heat exchanger and an upper box body, wherein the upper box body, the intermediate heat exchanger and the lower acid tank are connected by flange compression; the intermediate heat exchanger is a vertical shell and tube heat exchanger, which is composed of a shell, an upper tube sheet, a lower tube sheet, a quartz glass tube and a baffle; the upper tube sheet and the lower tube sheet are respectively arranged at the top and the bottom of the shell, and the two ends of the quartz glass tube are respectively fixed to the upper tube sheet and the lower tube sheet; a plurality of baffles for changing the flow direction of the cooling medium are arranged in the shell, and the middle part of the quartz glass tube is fixed to the baffle; a square demisting unit is arranged inside the upper box body, and the demisting unit is an acid-resistant fiber made of PTFE or PFA. The sulfuric acid vapor condenser is easy to operate and has strong industrial applicability. After being treated by the sulfuric acid vapor condenser, the tail gas emission can meet the environmental protection requirements, and the leakage of acid gas can be effectively avoided during use, and the safety is good.

[0007] Reference 2: Chinese patent document with publication number CN211752603U

[0008] Reference 2 records a condenser for sulfuric acid condensation, the condenser includes a tube heat exchanger and a plate heat exchanger, the tube heat exchanger is arranged below the plate heat exchanger, and a collecting tank is also arranged below the tube heat exchanger; a plurality of condensing tubes are arranged in the tube heat exchanger, and after the flue gas to be cooled passes through the condensing tubes and is cooled, the cooling material falls into the collecting tank along the tube wall of the condensing tube. The condenser uses a combination of a plate heat exchanger and a tube heat exchanger, which reduces the length of the glass tube in the tube heat exchanger, and overcomes the problem that the overly long glass tube is easy to break and difficult to manufacture.

[0009] However, the existing condenser still has the following problems:

[0010] 1. The acidic process gas is not uniform when entering each glass tube, and the temperature difference between the inlet and outlet of the glass tube is large, which may easily lead to the breakage of the glass tube during long-term operation.

[0011] 2. The sealing performance between the tube sheet and the glass tube of the condenser is unstable and prone to leakage. Summary of the invention

[0012] The purpose of the present invention is to solve the technical problems of glass tubes being easily broken and leakage between tube sheets and glass tubes in condensers in the prior art, and to provide a zero-leakage vertical acid condenser.

[0013] The present invention solves the above-mentioned technical problems and adopts the following technical solutions: a zero-leakage vertical acid condenser, comprising an upper tube box, a lower tube box and a vertical tube shell heat exchange assembly, wherein the vertical tube shell heat exchange assembly comprises a shell, an upper tube sheet, a lower tube sheet, a glass heat exchange tube and a baffle, the upper and lower parts of the shell are respectively provided with an air inlet and an air outlet, the upper tube box and the lower tube box are respectively provided with a smoke outlet and a smoke inlet, and the bottom of the lower tube box is provided with an acid discharge port;

[0014] The upper tube plate is composed of a PTFE plate and a metal reinforcement plate located below the PTFE plate;

[0015] The lower tube plate is composed of a PTFE plate and a metal reinforcement plate located above it, or a metal plate wrapped with a PTFF / PFA layer;

[0016] The glass heat exchange tube is a reducer tube or a segmented plug-in tube;

[0017] If the glass heat exchange tube is a reducer, its large diameter section matches the upper tube sheet, and the small diameter section matches the lower tube sheet, and the outer diameter of the small diameter section is smaller than the inner diameter of the sealing ring matched with the large diameter section, the upper port of the large diameter section is flush with the upper end surface of the upper tube sheet, and an upper hanging internal spiral spoiler is provided in the reducer;

[0018] If the glass heat exchange tube is a segmented plug-in tube, it is composed of an upper tube body and a lower tube body plugged together, a support plate is provided in the middle of the shell, the support plate is provided with a through hole for the lower tube body of the glass heat exchange tube to pass through, the upper end of the lower tube body is provided with an expanded diameter portion, after the lower tube body is assembled, the expanded diameter portion is located above the support plate, the upper tube body is inserted into the expanded diameter portion of the lower tube body, the upper end of the upper tube body is flush with the upper end surface of the upper tube plate, and an upper-hanging internal spiral spoiler is provided in the upper tube body;

[0019] A wire mesh demister is arranged in the upper tube box.

[0020] As a further optimization of the zero-leakage vertical acid condenser of the present invention: the upper end surface of the PTFE plate of the upper tube plate is provided with an avoidance groove, the upper end of the upper tube body has an outer edge placed in the avoidance groove, and the upper tube body and the PTFE plate are sealed by a sealing ring.

[0021] As a further optimization of the zero-leakage vertical acid condenser of the present invention: the lower tube plate is composed of a PTFE plate and a metal reinforcement plate located on the inner side thereof, and the PTFE plate and the metal reinforcement plate are fixed together by screws.

[0022] As a further optimization of the zero-leakage vertical acid condenser of the present invention: the lower tube body and the lower tube plate are sealed by a sealing ring or a sealing sleeve.

[0023] As a further optimization of the zero-leakage vertical acid condenser of the present invention: the connection between the end of the upper tube body and the end of the lower tube body is sealed by covering the sleeve.

[0024] As a further optimization of the zero-leakage vertical acid condenser of the present invention: the end of the upper tube body and the end of the lower tube body are sealed by a sealing ring.

[0025] As a further optimization of the zero-leakage vertical acid condenser of the present invention: a support ring is arranged in the annular gap between the lower tube body and the support plate.

[0026] As a further optimization of the zero-leakage vertical acid condenser of the present invention: an upper flange is provided on the upper tube body.

[0027] As a further optimization of the zero-leakage vertical acid condenser of the present invention: a rectifying wall made of acid-resistant bricks is arranged at the bottom of the lower tube box, the rectifying wall is located on one side of the acid discharge port and faces the flue gas inlet, and a through hole is arranged at the bottom of the rectifying wall.

[0028] As a further optimization of the zero-leakage vertical acid condenser of the present invention: a temperature measuring port is provided on the upper side wall of the lower tube box.

[0029] The present invention has the following beneficial effects:

[0030] 1. In the acid condenser of the present invention, the high-temperature process gas enters the acid cooler from the bottom side, and a rectifying wall (acid-resistant brickwork) is arranged at the bottom, so that the process gas enters each glass tube evenly, reducing the probability of glass tube breakage and improving the heat exchange performance of the entire heat exchanger.

[0031] 2. In the acid condenser of the present invention, the upper tube sheet and the glass heat exchange tube adopt a zero leakage sealing form, and the lower tube sheet adopts a zero leakage sealing form, which can achieve zero leakage of the acid condenser.

[0032] 3. The heat exchange glass tube of the acid condenser of the present invention can adopt a reducer tube, wherein the large diameter section is not greater than 200 mm, and the rest are small diameter sections, and the outer diameter of the small diameter section is smaller than the inner diameter of the sealing ring matched with the large diameter section. The large diameter section is matched with the upper tube sheet, and the small diameter section is matched with the lower tube sheet. The tube is first passed through the upper tube sheet and finally through the lower tube sheet. The tube passing efficiency is improved, the glass tube breakage rate is reduced, and the stability of normal operation is improved.

[0033] 4. Different from the prior art, the glass heat exchange tube of the present invention does not have a demisting screen installed inside, the upper end of the glass heat exchange tube is flush with the upper surface of the upper tube plate, and the sulfuric acid in the upper tube box can flow from each glass tube to the lower tube box. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a schematic diagram of the overall structure of the acid condenser (first perspective);

[0035] Figure 2 It is the overall structural schematic diagram of the acid condenser (second perspective);

[0036] Figure 3 for Figure 1 A schematic diagram of the enlarged local structure at point A in the middle;

[0037] Figure 4 It is a schematic diagram of the plug-in structure of the upper tube body and the lower tube body of the glass heat exchange tube in the acid condenser (form one);

[0038] Figure 5 It is a schematic diagram of the plug-in structure of the upper tube body and the lower tube body of the glass heat exchange tube in the acid condenser (form 2);

[0039] Figure 6 It is a structural schematic diagram of the upper tube plate in the acid condenser;

[0040] Figure 7 It is a structural schematic diagram of the lower tube plate in the acid condenser;

[0041] Figure 8 It is a structural schematic diagram of the lower tube body in the acid condenser;

[0042] Fig. 9 It is a structural schematic diagram of the lower tube body in the acid condenser;

[0043] Fig.10 It is a structural schematic diagram of the rectifying wall in the acid condenser;

[0044] Fig.11 It is a schematic diagram of the structure of the variable diameter heat exchange tube in the acid condenser;

[0045] Markings in the figure:

[0046] 1. Upper tube box;

[0047] 2. Lower pipe box;

[0048] 3. Vertical shell and tube heat exchange assembly;

[0049] 4. Rectification wall;

[0050] 301, housing;

[0051] 302, upper tube plate;

[0052] 303, lower tube plate;

[0053] 304, glass heat exchange tube;

[0054] 305, baffle;

[0055] 306, support plate;

[0056] 307, spiral spoiler;

[0057] 308. Wire mesh demister;

[0058] 309, screws;

[0059] 310, sealing sleeve;

[0060] 311, covering casing;

[0061] 312, support ring;

[0062] 3041. Upper tube body;

[0063] 3042, lower tube body. DETAILED DESCRIPTION

[0064] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with embodiments, but the content of the present invention is not limited to the following embodiments.

[0065] like Figure 1-3 As shown: A zero-leakage vertical acid condenser includes an upper tube box 1, a lower tube box 2 and a vertical tube shell heat exchange assembly 3. The vertical tube shell heat exchange assembly 3 includes a shell 301, an upper tube sheet 302, a lower tube sheet 303, a glass heat exchange tube 304 and a baffle 305. The upper and lower parts of the shell 301 are respectively provided with an air inlet and an air outlet.

[0066] The upper pipe box 1, the lower pipe box 2 and the shell 301 are usually made of corrosion-resistant materials, such as stainless steel, titanium or acid-resistant alloy, to withstand the corrosion of acidic media. The thickness and material selection of the pipe box and the shell should be determined according to specific working conditions.

[0067] The tube sheet is used to support and fix the glass heat exchange tube bundle to ensure that the glass heat exchange tubes are stably arranged in the shell. The tube sheet also needs to be made of corrosion-resistant materials, and the strength and stability of the tube sheet during operation must also be considered.

[0068] In this embodiment, the upper tube plate 302 is composed of a PTFE plate and a metal reinforcement plate located below it (such as Figure 6 The specific structure of the lower tube plate 303 is as follows: The lower tube plate 303 is composed of a PTFE plate and a metal reinforcement plate located above it (such as Figure 7 and 8 ), the PTFE plate and the metal reinforcing plate are fixed together by screws 309. Or a metal plate wrapped with a PTFF / PFA layer (such as Fig. 9 shown).

[0069] PTFE sheet, also known as polytetrafluoroethylene sheet or Teflon sheet, is a material made of polytetrafluoroethylene resin formed by molding at room temperature, sintering and cooling. PTFE sheet can maintain stable performance in a very wide temperature range, and its high temperature resistance can reach 260°C. Even under extreme temperature changes, it can maintain the integrity of the material. At the same time, PTFE sheet has extremely strong chemical stability and is almost not corroded by any chemical substances, including strong acids, strong alkalis, aqua regia, etc. This makes it very useful in environments that require high corrosion resistance.

[0070] Spraying PTFE coating on the surface of metal plate is also a way to combine metal with PTFE. Spraying PTFE coating on metal plate can significantly improve the corrosion resistance and wear resistance of metal surface. For example, PTFE coating material is evenly distributed in solvent to form dispersion, and the dispersion is atomized and sprayed on the surface of metal plate by high pressure air. After drying and sintering steps, the coating is firmly combined with metal plate. Alternatively, dry processing method is adopted to make PTFE coating material into extremely fine solid particles. Use appropriate method to attach micro powder coating particles to the surface of metal plate. Heat in oven to melt the coating material and form a mesh structure with the surface of metal plate.

[0071] The glass heat exchange tube 304 is the core component of the condenser, and is composed of multiple corrosion-resistant glass tubes. These glass tubes are arranged vertically and fixed on the tube sheets at both ends. The acid gas to be condensed flows inside the glass heat exchange tube 304, while the outside of the glass heat exchange tube 304 is cooled by the cooling medium (air).

[0072] In the present invention, the glass heat exchange tube can be in two forms: a reducing tube or a segmented plug-in tube.

[0073] like Fig.11 As shown, the glass heat exchange tube 304 is a reducer tube, whose large diameter section (diameter not exceeding 200 mm) cooperates with the upper tube plate 302, and the small diameter section cooperates with the lower tube plate 303, and the outer diameter of the small diameter section is smaller than the inner diameter of the sealing ring matched with the large diameter section, and the upper port of the large diameter section is flush with the upper end surface of the upper tube plate 302, and an upper-mounted internal spiral spoiler 307 is provided in the reducer.

[0074] Figure 4 and 5 As shown, the glass heat exchange tube 304 is composed of an upper tube body 3041 and a lower tube body 3042 that are plugged together. A support plate 306 is provided in the middle of the shell 301. The support plate 306 is provided with a through hole for the lower tube body 3042 of the glass heat exchange tube 304 to pass through. The upper end of the lower tube body 3042 is provided with an expanded diameter portion. After the lower tube body 3042 is assembled, the expanded diameter portion is located above the support plate 306, and the upper tube body 3041 is inserted into the expanded diameter portion of the lower tube body 3042.

[0075] The upper port of the upper tube body 3041 is flush with the upper end surface of the upper tube plate 302, and the upper part is thickened. An upper hanging inner spiral spoiler 307 is arranged in the upper tube body 3041, and a wire mesh demister 308 is arranged in the upper tube box 1.

[0076] The upper end surface of the PTFE plate of the upper tube plate 302 is provided with an avoidance groove, and the upper end of the upper tube body 3041 has an outer edge placed in the avoidance groove, and the upper tube body 3041 and the PTFE plate are sealed by a sealing ring.

[0077] The insertion joint between the upper tube body 3041 and the lower tube body 3042 can be sealed in two ways. The connection between the end of the upper tube body 3041 and the end of the lower tube body 3042 is sealed by the covering sleeve 311.

[0078] The end of the upper tube 3041 and the end of the lower tube 3042 are sealed by a sealing ring.

[0079] The lower tube body 3042 and the lower tube plate 303 are sealed by a sealing ring or a sealing sleeve 310 .

[0080] A support ring 312 is disposed in the annular gap between the lower tube 3042 and the support plate 306 .

[0081] A rectifying wall 4 is provided at the bottom of the lower tube box 2. The rectifying wall 4 is made of acid-resistant bricks. The rectifying wall 4 is arranged facing the flue gas inlet, and a through hole is arranged at the bottom of the wall. The process gas enters each glass tube evenly, reducing the probability of glass tube breakage and improving the heat exchange performance of the entire heat exchanger. The acid-resistant insulation bricks are used as a cooling protective layer to cover the anti-corrosion layer without overheating. The bricks on the upper part of the protective layer are provided with a slope to facilitate the sulfuric acid to flow to the bottom.

[0082] A temperature measuring port is provided near the entrance of the glass tube in the lower tube box 2. When the temperature exceeds 260°C, cooling measures shall be adopted.

[0083] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. A zero-leakage vertical acid condenser, comprising an upper tube box (1), a lower tube box (2) and a vertical tube shell heat exchange assembly (3), wherein the vertical tube shell heat exchange assembly (3) comprises a shell (301), an upper tube sheet (302), a lower tube sheet (303), a glass heat exchange tube (304) and a baffle (305), and the upper and lower parts of the shell (301) are respectively provided with an air inlet and an air outlet, characterized in that: The upper tube plate (302) is composed of a PTFE plate and a metal reinforcement plate located below the PTFE plate; The lower tube plate (303) is composed of a PTFE plate and a metal reinforcement plate located above it, or is a metal plate wrapped with a PTFE / PFA layer; The glass heat exchange tube (304) is a reducer tube or a segmented plug-in tube; If the glass heat exchange tube (304) is a reducer tube, its large diameter section matches with the upper tube plate (302), and its small diameter section matches with the lower tube plate (303), and the outer diameter of the small diameter section is smaller than the inner diameter of the sealing ring matched with the large diameter section, and the upper end of the large diameter section is flush with the upper end surface of the upper tube plate (302), and an upper hanging type inner spiral spoiler (307) is provided in the reducer tube; If the glass heat exchange tube (304) is a segmented plug-in tube, it is composed of an upper tube body (3041) and a lower tube body (3042) plugged together, a support plate (306) is provided in the middle of the shell (301), the support plate (306) is provided with a through hole for the lower tube body (3042) of the glass heat exchange tube (304) to pass through, the upper end of the lower tube body (3042) is provided with an expanded diameter portion, after the lower tube body (3042) is assembled, the expanded diameter portion is located above the support plate (306), the upper tube body (3041) is inserted into the expanded diameter portion of the lower tube body (3042), the upper end of the upper tube body (3041) is flush with the upper end surface of the upper tube plate (302), and an upper-hanging inner spiral spoiler (307) is provided in the upper tube body (3041); A wire mesh demister (308) is provided in the upper tube box (1).

2. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The upper end surface of the PTFE plate of the upper tube plate (302) is provided with an avoidance groove, and the upper end of the upper tube body (3041) has an outer edge placed in the avoidance groove, and the upper tube body (3041) and the PTFE plate are sealed by a sealing ring.

3. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The lower tube plate (303) is composed of a PTFE plate and a metal reinforcement plate located inside the PTFE plate, and the PTFE plate and the metal reinforcement plate are fixed together by screws (309).

4. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The lower tube body (3042) and the lower tube plate (303) are sealed via a sealing ring or a sealing sleeve (310).

5. A zero-leakage vertical acid condenser as claimed in claim 6, characterized in that: The connection between the end of the upper tube body (3041) and the end of the lower tube body (3042) is sealed by a covering sleeve (311).

6. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The end of the upper tube body (3041) and the end of the lower tube body (3042) are sealed by a sealing ring.

7. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: A support ring (312) is provided in the annular gap between the lower tube body (3042) and the support plate (306).

8. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The upper portion of the upper tube body (3041) is provided with a flange.

9. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: A rectifying wall (4) is arranged at the bottom of the lower tube box (2). The rectifying wall (4) is made of acid-resistant bricks. The rectifying wall (4) is arranged facing the smoke inlet, and a through hole is arranged at the bottom of the wall.

10. A zero-leakage vertical acid condenser as claimed in claim 1, characterized in that: The lower tube box (2) is provided with a temperature measuring port close to the entrance of the glass tube.

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