Reboiler for reusing polyolefin heavy components
By introducing a three-stage material distribution system and an inner groove fin-type heat exchange tube structure into the polyolefin recombination reboiler, the problem of poor heat transfer effect is solved, and efficient flow boiling heat transfer and energy consumption reduction is achieved.
Patent Information
- Application Number
- CN202422062960.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-26
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2034-08-26
AI Technical Summary
The existing siphon heat exchanger has poor heat transfer effect in polyolefin devices and the material dwells for a long time, which affects subsequent process optimization.
The material three-stage distribution system, inner groove fin heat exchange tube and steam coil structure are adopted, including cross distribution tube, screen plate distribution box and single-tube cyclone distributor, to optimize the reboiler structure of recombinant components such as carbon 8 and carbon 10 to improve the efficiency of flow boiling heat transfer.
It improves heat transfer effect, reduces energy consumption, optimizes material distribution, reduces liquid level fluctuations and dry wall phenomena, and improves evaporation efficiency.
Smart Images
Figure CN223196556U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of petrochemical refining equipment, and in particular relates to a reboiler for recycling polyolefin heavy components. Background Art
[0002] The heavy components such as C8 and C10 from the bottom of the deweighting tower of the polyolefin unit enter the C8 tower. Under the pressure reduction operation, the asphaltene at the bottom of the tower is extracted and sent to the residue oil cracking unit. Secondly, it passes through the siphon heat exchanger, is heated by steam and then boiled before returning to the C8 tower.
[0003] The current siphon heat exchanger has problems such as poor heat transfer effect and long material residence time, which has a great impact on subsequent process optimization. Utility Model Content
[0004] The purpose of the utility model is to overcome the deficiencies in existing products and provide a reboiler with high heat transfer efficiency.
[0005] In order to achieve the above-mentioned purpose, the present invention provides the following technical solution: a reboiler for recycling polyolefin heavy components, comprising a reboiler body, characterized in that a feed pipe is provided on the top of the reboiler body, a three-stage material distribution system is connected below the feed pipe, and the three-stage material distribution system is connected to an inner groove fin-type heat exchange tube sealedly arranged in the middle of the reboiler body.
[0006] Specifically, the above-mentioned reboiler for recycling polyolefin heavy components, the three-stage material distribution system includes a first-level cross distribution pipe, a second-level sieve plate distribution box and a third-level single-tube swirl distributor. The cross distribution pipe is directly fixed to the bottom of the feed pipe, the sieve plate distribution box is fixed outside the cross distribution pipe, and a single-tube swirl distributor is separately installed on the top of each of the inner groove fin-type heat exchange tubes.
[0007] Specifically, in the above-mentioned reboiler for recycling polyolefin heavy components, the bottom of the cross distribution pipe has 5 rows of distribution holes evenly distributed within a range of 120 degrees.
[0008] Specifically, in the above-mentioned reboiler for recycling the polyolefin heavy component, the sieve plate distribution box is fixed overhead with bolts just above each single-tube cyclone distributor.
[0009] Specifically, in the above-mentioned reboiler for recycling polyolefin heavy components, the single-tube swirl distributor protrudes from the plane where the top of the inner groove fin-type heat exchange tube is located.
[0010] Specifically, in the above-mentioned reboiler for recycling polyolefin heavy components, the inner grooved-fin type heat exchange tube is provided with a grooved-fin type inner wall.
[0011] Specifically, in the above-mentioned reboiler for recycling polyolefin heavy components, the outer diameter of the single-tube swirl distributor is 6 mm smaller than the inner diameter of the inner groove fin type heat exchange tube, the length of the single-tube swirl distributor is 80 mm, and the tube head of the single-tube swirl distributor is a bell-mouth type, and the outer diameter of the tube head is 4 mm smaller than the inner diameter of the inner groove fin type heat exchange tube.
[0012] Specifically, in the above-mentioned reboiler for recycling polyolefin heavy components, the single-tube swirl distributor is connected to the inner grooved fin-type heat exchange tube through three wedge-shaped positioning blocks spot-welded on the outside.
[0013] Specifically, in the above-mentioned reboiler for recycling the polyolefin heavy component, a triangular overflow port is opened on the side of the single-tube cyclone distributor.
[0014] Specifically, in the reboiler for recycling the polyolefin heavy component, a steam coil is provided on the top of the reboiler body.
[0015] The utility model relates to a new type of reboiler application suitable for returning heavy components such as C8 and C10 in a polyolefin unit to a tower for reuse. The equipment mainly includes a three-stage material distribution system, a single-tube swirl distributor, an inner groove fin-type heat exchange tube, and a steam coil for external heating of inlet and outlet materials, thereby improving the flow boiling heat transfer efficiency of the equipment.
[0016] The three-stage material distribution system mainly includes a first-level cross distribution pipe, a second-level sieve plate distribution box, and a third-level single-tube swirl distributor. The first-level cross distribution pipe has a total of 5 rows of distribution holes processed within a 120° range. The second-level sieve plate distribution box is fixed with bolts and placed directly above the single-tube swirl distributor. The third-stage single-tube swirl distributor distributes the C8 and C10 materials evenly to each heat exchange tube by overflow, and flows downward in a film-like manner along the inner groove wing wall of the heat exchange tube, so that the reboiler feed liquid level is stable and the flow rate is controllable. Fluctuations in the flow rate will not cause fluctuations in the liquid level, or dry wall or liquid-filled tubes, so that the film on the inner wall of the heat exchange tube is evenly distributed.
[0017] The three-stage single-tube swirl distributor mainly processes a tube head with an outer diameter 6mm smaller than the inner diameter of the heat exchange tube and a length of 80mm. Three wedge-shaped positioning blocks are spot-welded on the outside of the tube head to fix it to the inner diameter of the heat exchange tube. After a straight groove is processed on the inside, a bell mouth is processed on the tube head. Three triangular overflow ports are evenly distributed on the side to distribute the overflow evenly.
[0018] The internal grooved fin heat exchange tube mainly adopts a grooved fin structure, and the grooves and fins are machined on the inner surface of the smooth tube to enhance the flow boiling heat transfer process.
[0019] The inlet and outlet materials are heated by external steam coils, which mainly involves setting steam heating coils on the outside of the inlet and outlet pipe boxes to increase the inlet and outlet temperatures of the materials, thereby improving the reboiling effect.
[0020] Compared with the existing technology, the beneficial effect of the reboiler for recycling polyolefin heavy components of the utility model is as follows: the equipment optimizes the reboiler structure of the original polyolefin device for returning carbon 8, carbon 10 and other heavy components to the tower for reboiling by fully adopting the main structures such as the three-stage material distribution system and the inner groove fin-type heat exchange tube. The modified heat exchanger has the advantages of a wide viscosity range, low pressure drop, good heat transfer effect, and high evaporation efficiency. It can reduce the energy consumption of traditional tower bottom heat exchange equipment by more than 20% with minimal investment, and has great energy-saving potential. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 This is a schematic diagram of a reboiler for recycling polyolefin heavy components according to the present invention.
[0022] Figure 2 This is a schematic diagram of a three-stage distribution system of a reboiler for recycling polyolefin heavy components in the utility model.
[0023] Figure 3 This is a schematic diagram of a single-tube cyclone distributor of a reboiler for recycling polyolefin heavy components according to the present invention.
[0024] Figure 4 This is a schematic diagram of the inner groove fin type heat exchange tube of a reboiler for recycling polyolefin heavy components according to the utility model.
[0025] Figure 5 for Figure 4 A partial enlarged view of the inner groove fin type heat exchange tube.
[0026] Among them: 1, sieve plate distribution box 2, steam coil 3, single-tube swirl distributor 301, distribution channel 302, wedge-shaped positioning block 4, inner groove fin type heat exchange tube 401, groove fin type inner wall 5, feed pipe 501, cross distribution pipe 6, upper sealing layer 7, lower sealing layer. DETAILED DESCRIPTION
[0027] The following is combined with Figure 1 The embodiments of the present invention are described in more detail with reference to the accompanying drawings so that those skilled in the art can implement the invention accordingly after studying the specification.
[0028] Refer to the attached Figure 1 : The utility model is a reboiler for recycling polyolefin heavy components, including a reboiler body, which is sealed and divided into three parts: top, middle and bottom by an upper sealing layer 6 and a lower sealing layer 7. A steam coil 2 is provided on the top of the reboiler body.
[0029] Refer to the attached Figure 2The reboiler body is topped with a feed pipe 5, connected to a three-stage material distribution system. This system is connected to the inner fluted fin heat exchange tubes 4, which are sealed and positioned in the middle of the reboiler body. The inner fluted fin heat exchange tubes 4 connect the top and bottom of the reboiler body. The three-stage material distribution system comprises a cross-shaped distribution pipe 501 (primary), a sieve plate distribution box 1 (secondary), and a single-tube swirl distributor 3 (tertiary). The cross-shaped distribution pipe 501 is directly fixed to the bottom of the feed pipe 5, while the sieve plate distribution box 1 is fixed to the outside of the cross-shaped distribution pipe 501. Each inner fluted fin heat exchange tube 4 is topped with a separate single-tube swirl distributor 3. The bottom of the cross-shaped distribution pipe 501 has five rows of distribution holes evenly spaced over a 120-degree angle. The sieve plate distribution box 1 is bolted overhead directly above each single-tube swirl distributor 3. The single-tube swirl distributor 3 protrudes above the plane of the inner fluted fin heat exchange tube 4.
[0030] Refer to the attached Figure 3 : A distribution channel 301 is opened obliquely up and down in the single-tube swirl distributor 3, and a wedge-shaped positioning block 302 is spot-welded on the outside of the single-tube swirl distributor 3. The single-tube swirl distributor 3 is connected to the inner groove fin type heat exchange tube 4 through the wedge-shaped positioning block 302. A triangular overflow port is opened on the side of the single-tube swirl distributor 3.
[0031] The outer diameter of the single-tube swirl distributor 3 is 6 mm smaller than the inner diameter of the inner groove fin type heat exchange tube 4. The length of the single-tube swirl distributor 3 is 80 mm. The tube head of the single-tube swirl distributor 3 is a bell-mouth type. The outer diameter of the tube head is 4 mm smaller than the inner diameter of the inner groove fin type heat exchange tube 4.
[0032] Refer to the attached Figure 4 、 5 The inner grooved-fin heat exchange tubes 4 are provided with grooved-fin inner walls 401. The single-tube swirl distributor 3 distributes the C8 and C10 materials evenly to each inner grooved-fin heat exchange tube 4 through overflow, and the materials flow downward in a film-like manner along the inner grooved-fin inner walls 401 of the heat exchange tubes. This ensures a stable reboiler feed level and controllable flow rate, preventing level fluctuations caused by flow rate fluctuations, dry wall formation, or liquid-filled tubes. The inner walls of the heat exchange tubes are evenly coated with the film.
[0033] The above is a description of one or more embodiments of the present invention, and while the description is relatively specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the scope of the present invention, and these modifications and improvements fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.
Claims
1. A reboiler for recycling polyolefin heavy components, comprising a reboiler body, characterized in that: A feed pipe (5) is provided on the top of the reboiler body, a three-stage material distribution system is connected below the feed pipe (5), and the three-stage material distribution system is connected to an inner groove fin type heat exchange tube (4) sealed and arranged in the middle of the reboiler body.
2. The reboiler for recycling polyolefin heavy components according to claim 1, characterized in that: The three-stage material distribution system includes a first-stage cross distribution pipe (501), a second-stage sieve plate distribution box (1) and a third-stage single-tube swirl distributor (3). The cross distribution pipe (501) is directly fixed to the bottom of the feed pipe (5), the sieve plate distribution box (1) is fixed outside the cross distribution pipe (501), and a single-tube swirl distributor (3) is separately installed on the top of each inner groove fin type heat exchange tube (4).
3. The reboiler for recycling polyolefin heavy components according to claim 2, characterized in that: The bottom of the cross distribution pipe (501) is evenly distributed with 5 rows of distribution holes within a range of 120 degrees.
4. The reboiler for recycling polyolefin heavy components according to claim 2, characterized in that: The sieve plate distribution box (1) is fixed overhead with bolts just above each single-tube cyclone distributor (3).
5. The reboiler for recycling polyolefin heavy components according to claim 2, characterized in that: The single-tube swirl distributor (3) protrudes from the plane where the top of the inner groove fin-type heat exchange tube (4) is located.
6. The reboiler for recycling polyolefin heavy components according to claim 5, characterized in that: The inner groove-fin type heat exchange tube (4) is provided with a groove-fin type inner wall (401).
7. The reboiler for recycling polyolefin heavy components according to claim 2, characterized in that: The outer diameter of the single-tube swirl distributor (3) is 6 mm smaller than the inner diameter of the inner groove fin type heat exchange tube (4), the length of the single-tube swirl distributor (3) is 80 mm, and the tube head of the single-tube swirl distributor (3) is a bell-mouth type, and the outer diameter of the tube head is 4 mm smaller than the inner diameter of the inner groove fin type heat exchange tube (4).
8. A reboiler for recycling polyolefin heavy components according to claim 2 or 7, characterized in that: The single-tube swirl distributor (3) is connected to the inner grooved fin-shaped heat exchange tube (4) through three wedge-shaped positioning blocks (302) spot-welded on the outside.
9. A reboiler for recycling polyolefin heavy components according to claim 2 or 7, characterized in that: The single-tube swirl distributor (3) is provided with a triangular overflow port on the side.
10. The reboiler for recycling polyolefin heavy components according to claim 1, characterized in that: A steam coil (2) is provided on the outside of the top of the reboiler body.