Jacket inlet connecting piece and quenching heat exchanger with same

Abstract

The utility model relates to the technical field of petrochemical equipment, in particular to a jacket inlet connecting piece and a quenching heat exchanger with the jacket inlet connecting piece, which comprises a lower central pipe and an inlet outer pipe, the lower central pipe is positioned in the inlet outer pipe, a lower annular channel with a sealed bottom is formed between the lower central pipe and the inlet outer pipe, and the lower central pipe and the inlet outer pipe are communicated with a transversely arranged jacket medium introduction pipe; the heat exchanger is characterized in that the axis of the jacket medium introduction pipe and the axis of the inlet outer pipe are arranged in a staggered mode, and the inner wall of the jacket medium introduction pipe and the inner wall of the inlet outer pipe are arranged in a tangent mode. The cooling medium flows spirally after entering the lower annular channel, solid impurities are difficult to deposit and gather under the spiral thrust of the cooling medium, and the cooling medium flows more smoothly in the lower annular channel, so that the flow state is improved, the impact is reduced, and the equipment stability is improved. Moreover, the upper port of the lower central pipe and the jacket medium introduction pipe are staggered, namely, a welding seam between the lower central pipe and the inner sleeve is staggered from the jacket medium introduction pipe, so that the service life of the welding seam is prevented from being influenced by washing of high-pressure saturated water.

Description

Technical Field

[0001] The utility model relates to the technical field of petrochemical equipment, in particular to a jacket inlet connector and a quenching heat exchanger with the same. Background Art

[0002] The cracking furnace is a key unit of the ethylene plant. After the cracking raw materials are cracked at high temperature in the cracking furnace tube, they enter the quench heat exchanger for rapid cooling to prevent the occurrence of secondary reactions, reduce olefin losses, and recover heat energy to generate steam. With the development of ethylene cracking furnace quenching technology, in order to further shorten the residence time of the adiabatic section of the quench heat exchanger and avoid the problem of uneven distribution of cracked gas, most of the quench heat exchangers for newly built and renovated cracking furnaces use linear quench heat exchangers.

[0003] The linear quench heat exchanger is mainly composed of an inlet connector, a double-tube heat exchange element, a cooling medium connector, an outlet connector, a water vapor header, a high-temperature medium header, a hydraulic coke removal hole, etc. Based on this, the structure of the linear quench heat exchanger is as follows: Each double-tube heat exchange element is composed of two concentric tubes, wherein the inner tube (tube side) carries the high-temperature medium - cracked gas at about 800°C, and the annular gap (shell side or jacket) between the outer tube and the inner tube carries the cooling medium - a water vapor mixture at about 350°C. Each double-tube heat exchange element is connected to the outlet furnace tube of the cracking furnace through the inlet connector, and the double-tube heat exchange elements are arranged in parallel in a single row or double row, and are connected together through a water vapor header and a high-temperature medium header to form a linear quench heat exchanger.

[0004] Long-term operation of the shell and tube heat exchanger will cause the equipment to be blocked by scale, which will reduce efficiency, increase energy consumption and shorten life. If the scale cannot be removed in time, there will be a risk of equipment maintenance, shutdown or scrapping and replacement.

[0005] The bottom of the annular groove of the inlet connector of a traditional shell-and-tube heat exchanger is parallel to the cooling inlet axis. The flow of the cooling medium may theoretically form a medium retention area directly opposite the inlet. The medium retention area has a small scouring force due to the intersection of water flows in the annular channels, which can easily cause the deposition of suspended solids and the formation of scale, greatly increasing the possibility of scouring damage at this location, reducing the strength of the tube, and affecting the safety and service life of the equipment.

[0006] Therefore, the applicant has previously developed a jacket anti-solid deposition structure for a shell and tube heat exchanger as disclosed in the Chinese patent document with announcement number CN216385198U, including an inner sleeve, an outer sleeve, an inlet connector and an outlet connector, the inner sleeve is concentrically inserted into the outer sleeve, and an annular jacket channel is formed between the outer wall of the inner sleeve and the inner wall of the outer sleeve; the bottom of the lower annular channel is an inclined surface that gradually increases in the direction away from the jacket medium inlet pipe. During operation, the cooling water flowing in from the jacket medium inlet pipe will flow around the annular space and meet and intersect at the opposite side. Since the place is higher, it can be drained to form an upward component, which can avoid the cooling medium static zone that appears at the position opposite to the inlet, making it difficult for solid suspended matter to deposit and accumulate at this place, thereby avoiding the defect of solid impurities depositing the cooling medium at this position. The structure is simple and the manufacturing cost is low, and it is suitable for various shell and tube heat exchanger equipment.

[0007] The axis of the jacket medium introduction pipe passes through the axis of the inner sleeve / outer sleeve, that is, it is arranged in the center, and the inflowing cooling medium flows toward both sides of the lower annular channel and meets and intersects on the opposite side. The applicant further discovered in research and development that the inlet flow state can be further improved to avoid the deposition of impurities at the bottom. In addition, the applicant found that in some prior art, the weld between the upper end of the lower center pipe and the lower end of the inner sleeve is aligned with the jacket medium introduction pipe. When in use, high-pressure saturated water flushes the weld, affecting the service life of the equipment. Summary of the invention

[0008] In view of the above technical problems in the prior art, the utility model provides a jacket inlet connector and a quench heat exchanger with the same.

[0009] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0010] Provided is a jacket inlet connector, comprising a lower central tube and an inlet outer tube, wherein the lower central tube is located in the inlet outer tube, a lower annular channel with a bottom sealed is formed between the lower central tube and the inlet outer tube, and a jacket medium introduction tube arranged transversely is connected thereto, wherein the axis of the jacket medium introduction tube is staggered with the axis of the inlet outer tube, and the inner wall of the jacket medium introduction tube is tangent to the inner wall of the inlet outer tube; and the upper port of the lower central tube is staggered with the jacket medium introduction tube.

[0011] As a further optional solution, the inner diameter of the jacket medium introduction pipe is r, the inner diameter of the inlet outer pipe is R, and r≤1 / 2R.

[0012] As a further optional solution, the jacket medium introduction pipe is arranged perpendicularly to the inlet outer pipe.

[0013] As a further optional solution, the lower central tube and / or the inlet outer tube are circular tubes.

[0014] As a further optional solution, the bottom of the lower annular channel is an inclined surface, and the jacket medium introduction pipe is connected to the lower position of the inclined surface; or the bottom of the lower annular channel is a constant height surface.

[0015] As a further optional solution, the inlet outer pipe includes an expanded diameter section and a connecting pipe section from bottom to top, the inner diameter of the expanded diameter section is larger than the inner diameter of the connecting pipe section, and the jacket medium introduction pipe is connected to the expanded diameter section.

[0016] As a further optional solution, a tapered transition section is provided between the diameter expansion section and the connecting pipe section.

[0017] As a further optional solution, the lower center pipe and the inlet outer pipe are integrally cast structures.

[0018] The utility model also provides a rapid cooling heat exchanger, which is characterized in that it includes an inner sleeve, an outer sleeve, an outlet connector and an inlet connector, the inlet connector is the jacket inlet connector, the inner sleeve is concentrically inserted into the outer sleeve, and an annular jacket channel is formed between the outer wall of the inner sleeve and the inner wall of the outer sleeve; the lower center tube of the inlet connector is welded to fix the lower end of the inner sleeve, and the inlet outer tube is welded to fix the lower end of the outer sleeve.

[0019] As a further optional scheme, the outlet connecting piece includes an upper center tube and an outlet outer tube. The upper center tube is connected to the upper end of the inner sleeve and is passed through the outlet outer tube. An upper annular channel with a top seal is formed between the upper center tube and the outlet outer tube. The outlet outer tube is connected to the upper end of the outer sleeve and is connected to a laterally arranged cooling medium lead-out pipe.

[0020] Beneficial effects of the utility model:

[0021] Compared with the prior art, the utility model discloses a jacket inlet connector and a rapid cooling heat exchanger with the same. Since the axis of the jacket medium inlet pipe is staggered with the axis of the inlet outer pipe, and the inner wall of the jacket medium inlet pipe is tangent to the inner wall of the inlet outer pipe, the cooling medium flows in a spiral after entering the lower annular channel, and solid impurities are difficult to deposit and gather under the spiral thrust of the cooling medium. Moreover, the cooling medium flows more smoothly in the lower annular channel, improving the flow state and thus reducing the impact, thereby improving the stability of the equipment. Furthermore, the upper port of the lower center pipe is staggered with the jacket medium inlet pipe, that is, the weld between the lower center pipe and the inner sleeve is staggered with the jacket medium inlet pipe, so as to avoid the weld being affected by the scouring of high-pressure saturated water and affecting its service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the structure of the rapid cooling heat exchanger in the embodiment.

[0023] Figure 2 It is a three-dimensional diagram of the first embodiment of the inlet connector of the utility model.

[0024] Figure 3 It is a plan view of the first embodiment of the inlet connector of the utility model.

[0025] Figure 4 for Figure 3 A cross-sectional view with AA as the section.

[0026] Figure 5 It is a schematic diagram of the second embodiment of the inlet connector of the utility model.

[0027] Figure 6 for Figure 5 The sectional view with section BB as the section.

[0028] Figure 7 It is a three-dimensional diagram of the third embodiment of the inlet connector of the utility model.

[0029] Figure 8 This is a schematic diagram of the internal structure of the third embodiment of the inlet connector of the utility model.

[0030] Reference numerals:

[0031] Inner casing 1, outer casing 2, jacket channel 3

[0032] Inlet connector 4, lower center pipe 41, inlet outer pipe 42, diameter expansion section 421, connecting pipe section 422, conical transition section 423, lower annular channel 43, jacket medium introduction pipe 44;

[0033] Outlet connector 5 and cooling medium outlet pipe 51. DETAILED DESCRIPTION

[0034] The following will be combined with the accompanying drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0035] The quench heat exchanger of this embodiment is as follows Figures 1 to 6As shown, it includes an inner sleeve 1, an outer sleeve 2, an inlet connector 4 and an outlet connector 5. The inner sleeve 1 is concentrically inserted into the outer sleeve 2, and an annular jacket channel 3 is formed between the outer wall of the inner sleeve 1 and the inner wall of the outer sleeve 2. The inlet connector 4 includes a lower central tube 41 and an inlet outer tube 42. The lower central tube 41 is connected to the lower end of the inner sleeve 1 and is inserted into the inlet outer tube 42. A lower annular channel 43 with a bottom seal is formed between the lower central tube 41 and the inlet outer tube 42. The bottom surface of the lower annular channel 43 is a concave arc groove surface. The inlet outer tube 42 is connected to the lower end of the outer sleeve 2 and is connected to a jacket medium introduction pipe 44 arranged laterally. The lower central tube 41 and the inlet outer tube 42 and the jacket medium introduction pipe 44 are a common integral casting structure. The lower central tube 41 and the lower end of the inner sleeve 1, and the inlet outer tube 42 and the lower end of the outer sleeve 2 are both welded fixed structures.

[0036] As the main improvement in this embodiment, the axis of the jacket medium introduction pipe 44 is staggered with the axis of the inlet outer pipe 42, and the inner wall of the jacket medium introduction pipe 44 is tangent to the inner wall of the inlet outer pipe 42. After the cooling medium enters the lower annular channel 43, it flows in a spiral, and solid impurities are difficult to deposit and accumulate under the spiral thrust of the cooling medium. In addition, the cooling medium flows more smoothly in the lower annular channel 43, improving the flow state and thus reducing the impact, thereby improving the stability of the equipment. Furthermore, the upper port of the lower center pipe 41 is staggered with the jacket medium introduction pipe 44, that is, the weld between the lower center pipe 41 and the inner sleeve 1 is improved, so that the weld is staggered with the jacket medium introduction pipe 44, so as to avoid the weld being affected by the scouring of high-pressure saturated water and affecting its life.

[0037] In this embodiment, the inner diameter of the jacket medium introduction pipe 44 is r, and the inner diameter of the inlet outer pipe 42 is R, r≤1 / 2R, that is, the inner diameter of the jacket medium introduction pipe 44 is not larger than the inner radius of the inlet outer pipe 42, so that all the cooling medium flows in a unidirectional spiral in the lower annular channel 43, further improving the flow state.

[0038] In this embodiment, the jacket medium introduction pipe 44 is arranged perpendicularly to the inlet outer pipe 42. The lower center pipe 41 and the inlet outer pipe 42 are circular tubes.

[0039] like Figure 3 In the embodiment shown, the bottom of the lower annular channel 43 is a plane of equal height. Figure 5 In the embodiment shown, the bottom of the lower annular channel 43 is an inclined surface, specifically, inclined radially, or inclined around an annular spiral, and the jacket medium introduction pipe 44 is connected to the lower position of the inclined surface. Preferably, the inclined surface can push the solid impurities spiral upward to avoid the precipitation of solid impurities, and there is no need to set a normally closed sewage pipe separately, saving manufacturing costs and work efficiency.

[0040] like Figure 6As shown, the inlet outer pipe 42 includes an expanded diameter section 421 and a connecting pipe section 422 from bottom to top, the inner diameter of the expanded diameter section 421 is larger than the inner diameter of the connecting pipe section 422, the jacket medium introduction pipe 44 is connected to the expanded diameter section 421, and the connecting pipe section 422 is connected to the inner sleeve 1. After the cooling medium enters the lower annular channel 43, there is a large space, the medium flow is large, and solid deposition is further prevented. A conical transition section 423 is provided between the expanded diameter section 421 and the connecting pipe section 422.

[0041] In this embodiment, the outlet connector 5 can adopt the existing technology, which includes an upper central tube and an outlet outer tube. The upper central tube is connected to the upper end of the inner sleeve 1 and is inserted into the outlet outer tube. An upper annular channel with a top seal is formed between the upper central tube and the outlet outer tube. The outlet outer tube is connected to the upper end of the outer sleeve 2 and is connected to a transversely arranged cooling medium outlet pipe 51. The upper central tube and the outlet outer tube are an integrally formed structure. The upper central tube and the upper end of the inner sleeve 1, and the outlet outer tube and the upper end of the outer sleeve 2 are both welded fixed structures.

[0042] In the description of the present invention, it is obvious that the described embodiments are only some embodiments of the present invention, rather than all embodiments. The components of the embodiments of the present invention generally described and shown in the drawings herein can be arranged and designed in various different configurations.

[0043] Therefore, the above detailed description of the embodiments of the utility model provided in the accompanying drawings is not intended to limit the scope of the utility model claimed for protection, but merely represents selected embodiments of the utility model. Based on the embodiments of the utility model, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of the utility model.

[0044] In the description of the present utility model, it should be noted that the terms "middle", "upper", "lower", "horizontal", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or the positions or positional relationships in which the invented product is usually placed when in use, which are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific position, be constructed and operated in a specific position, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "disposed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be directly connected or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A jacket inlet connector, comprising a lower central tube and an inlet outer tube, wherein the lower central tube is located in the inlet outer tube, a lower annular channel with a bottom seal is formed between the lower central tube and the inlet outer tube, and is connected to a jacket medium introduction pipe arranged laterally, wherein: The axis of the jacket medium introduction pipe is staggered with the axis of the inlet outer pipe, and the inner wall of the jacket medium introduction pipe is tangent to the inner wall of the inlet outer pipe; the upper port of the lower center pipe is staggered with the jacket medium introduction pipe.

2. A jacket inlet connector according to claim 1, characterized in that: The inner diameter of the jacket medium inlet pipe is r, and the inner diameter of the inlet outer pipe is R, r≤1 / 2R.

3. A jacket inlet connector according to claim 1, characterized in that: The jacket medium inlet pipe is arranged vertically to the inlet outer pipe.

4. A jacket inlet connector according to claim 1, characterized in that: The lower central tube and / or the inlet outer tube are round tubes.

5. A jacket inlet connector according to claim 1, characterized in that: The bottom of the lower annular channel is an inclined surface, and the jacket medium introduction pipe is connected to the lower position of the inclined surface; or the bottom of the lower annular channel is a constant height surface.

6. A jacket inlet connector according to claim 1, characterized in that: The inlet outer pipe comprises an expanded diameter section and a connecting pipe section from bottom to top, the inner diameter of the expanded diameter section is larger than the inner diameter of the connecting pipe section, and the jacket medium introduction pipe is connected to the expanded diameter section.

7. A jacket inlet connector according to claim 6, characterized in that: A tapered transition section is provided between the diameter expansion section and the pipe connection section.

8. A jacket inlet connector according to claim 1, characterized in that: The lower center pipe and the inlet outer pipe are an integrated casting structure.

9. A quench heat exchanger comprising an inner casing, an outer casing, an outlet connector and an inlet connector, characterized in that: The inlet connector is a jacket inlet connector as described in any one of claims 1 to 8, wherein the inner sleeve is concentrically inserted into the outer sleeve, and an annular jacket channel is formed between the outer wall of the inner sleeve and the inner wall of the outer sleeve; the lower center tube of the inlet connector is welded to fix the lower end of the inner sleeve, and the inlet outer tube is welded to fix the lower end of the outer sleeve.

10. The quench heat exchanger according to claim 9, characterized in that: The outlet connector includes an upper center tube and an outlet outer tube. The upper center tube is connected to the upper end of the inner sleeve and is passed through the outlet outer tube. An upper annular channel with a sealed top is formed between the upper center tube and the outlet outer tube. The outlet outer tube is connected to the upper end of the outer sleeve and is connected to a transversely arranged cooling medium lead-out pipe.

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