A liquid distributor suitable for use in a column reactor of a test apparatus

Abstract

The utility model discloses a liquid distributor suitable for test device multitubular reactor, it includes first distributor, second distributor who sets up up and down, the first distributor is distributed with small hole, and the second distributor is established on the reactor pipe board top above of reaction tube, the second distributor includes bottom plate, is equipped with with the reaction tube corresponding setting downcomer on bottom plate, and the lower extreme of downcomer is communicated with corresponding reaction tube through the reducing pipe. The neck pipe export size is slightly smaller than reaction tube, makes the liquid that enters reaction tube to fall on the torus of catalyst bed layer top circular surface center, is more favorable to the uniform distribution of liquid in catalyst bed layer. The liquid distributor provided by the utility model can evenly distribute raw materials in test device multitubular reactor to each reaction tube and carry out the reaction.

Description

Technical Field

[0001] This utility model relates to a liquid distributor suitable for a tubular reactor in a test apparatus, belonging to the field of fluid distribution technology for chemical equipment. Background Technology

[0002] In fixed-bed catalytic reactors, the uniform distribution of feedstock within the catalyst bed directly affects not only catalyst performance but also product distribution, product properties, and catalyst lifetime. Due to the low density of gases, uniform distribution can be achieved through proper catalyst loading and the resistance of the catalyst bed, eliminating the need for specialized distribution facilities. However, liquid feedstocks have a much higher density than gases, making uniform distribution impossible through catalyst bed resistance alone. Therefore, a distributor must be installed before liquid feedstocks enter the catalyst bed. Tubular reactors, a special type of fixed-bed reactor, are designed for catalytic processes with high exothermic (or endothermic) reaction rates and consist of multiple reaction tubes. This places higher demands on liquid feedstock distributors, especially for tubular reactors used in experimental settings. Past experience has shown that improperly designed liquid distributors have resulted in unsatisfactory reaction outcomes in experimental tubular reactors. Uneven feedstock distribution in experimental tubular reactors has been a major challenge for researchers, making the development of a liquid distributor suitable for experimental tubular reactors that can uniformly distribute liquid feedstock into each reaction tube imperative. Summary of the Invention

[0003] The technical problem to be solved by this utility model is to provide a liquid distributor suitable for a tubular reactor in an experimental device.

[0004] To address the aforementioned technical problems, this utility model provides a liquid distributor suitable for a tubular reactor in an experimental device. It includes a first distributor and a second distributor arranged vertically. The first distributor has small holes distributed on it, and the second distributor is located above the upper tube sheet of the reactor at the top of the reaction tubes. The second distributor includes a base plate with a downcomer corresponding to the reaction tube on the base plate. The lower end of the downcomer is connected to the corresponding reaction tube via a necking pipe. The outlet size of the necking pipe is slightly smaller than that of the reaction tube, causing the liquid entering the reaction tube to fall onto the annular surface near the center of the circular surface at the top of the catalyst bed, which is more conducive to the uniform distribution of liquid in the catalyst bed.

[0005] Preferably, the opening of each downcomer protrudes from the base plate and is provided with a bubble cap.

[0006] More preferably, the lower edge of the blister is 5-10 mm below the opening of the downcomer, and there is a gap between the inner wall of the blister and the outer wall of the downcomer, and a gap between the lower edge of the blister and the base plate. This is to ensure that the liquid falling on the base plate overflows into the downcomer in a timely manner through the flow section formed by the two and does not stagnate on the base plate.

[0007] More preferably, the sidewall of the blister pack is provided with ventilation strips.

[0008] Furthermore, the venting strip protrudes from the side wall of the bubble cap, and the bottom edge of the venting strip is 5mm higher than the downcomer opening, ensuring that the liquid falling on the distribution plate will not directly splash into the downcomer.

[0009] Furthermore, the ventilation strip protrudes 2-5mm from the outer surface of the blister pack and has an outward structure, ensuring that the liquid falling on the blister pack avoids the ventilation strip when flowing down the surface. Even if gas passes through the strip quickly, it will not carry the liquid into the downcomer and cause uneven liquid distribution.

[0010] Preferably, the bottom plate and the upper tube sheet of the reactor are both horizontally arranged.

[0011] Preferably, the downcomer, the narrowing pipe, and the reaction pipe are arranged coaxially.

[0012] Preferably, the downcomer, the narrowing pipe, and the reaction pipe are arranged perpendicular to the base plate.

[0013] Preferably, the inlet of the downcomer extends 10-30mm above the bottom plate, selected according to the feed flow rate and the allowable residence time of the liquid on the distribution plate, and the inlets of all downcomers are on the same horizontal plane; the bottom outlet of the constricted tube is inserted into the reaction tube by 5-10mm to avoid the gas in the feed carrying some liquid onto the reactor tube sheet when it flows out of the downcomer outlet, causing inconsistent liquid volume entering each reaction tube.

[0014] The liquid distributor provided by this invention can uniformly distribute raw materials into each reaction tube in the tubular reactor of the experimental device for reaction. Attached Figure Description

[0015] Figure 1 A schematic diagram of a liquid distributor for a tubular reactor in an experimental apparatus provided by this utility model;

[0016] Figure 2 This is a magnified view of a portion of the second distributor;

[0017] Figure 3 This is a magnified view of a portion of the blister pack. Detailed Implementation

[0018] To make this utility model more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0019] Example

[0020] like Figure 1As shown, this utility model provides a liquid distributor suitable for a tubular reactor in an experimental device. It includes a first distributor 1 and a second distributor 3 arranged vertically. The first distributor 1 has small holes 2 distributed on it, and the second distributor 3 is located above the upper tube plate 9 of the reactor at the top of the reaction tube 10. The first distributor 1 is a distribution plate installed between the upper end flange of the tubular reactor and the flange of the second distributor 3. The distribution plate is a flat plate with densely distributed small holes, and its edge rests on a pre-set concave edge during the machining of the upper flange of the second distributor 3. The upper surface of the first distributor 1 is lower than the upper flange surface of the second distributor 3 to avoid affecting the seal with the top end of the reactor. The orifice diameter on the distribution plate is selected according to the viscosity of the feed liquid; small holes are selected for low-viscosity liquids, and the orifice diameter needs to be appropriately enlarged for high-viscosity liquids. The opening ratio of the first distributor 1 is determined by the liquid flow rate through the holes. The function of the first distributor 1 is to allow the feed to slowly fall into the second distributor 3 after passing through the small holes, avoiding impact on the liquid surface accumulated on the bottom plate of the second distributor 3, thereby ensuring an equal amount of liquid entering each reaction tube 10.

[0021] like Figure 2 As shown, the second distributor 3 includes a base plate 5, on which a downcomer 6 is provided corresponding to the reaction tube 10. The lower end of the downcomer 6 is connected to the corresponding reaction tube 10 through a necked tube 8. The dimensions of the base plate 5 are the same as those of the upper tube sheet 9 of the reactor. The dimensions and number of downcomers 6 are the same as those of the reaction tubes 10, and they are arranged concentrically on the base plate 5 with the reaction tubes 10 below. If there is a space between the outlet of the downcomer 6 extending below the base plate 5 and the top opening of the reactor 10, the gas in the feed will carry some liquid onto the upper tube sheet 9 of the reactor when it flows out of the outlet of the downcomer 6, causing the amount of liquid entering each reaction tube 10 to be inconsistent. Therefore, the downcomer 6 extending below the base plate 5 uses a necked tube 8, and the outlet should be inserted 5-10 mm below the opening of the reaction tube 10 to ensure that the liquid entering the downcomer 6 flows completely into the corresponding reaction tube 10. The outlet size of the constricted tube 8 is slightly smaller than that of the reaction tube 10, so that the liquid entering the reaction tube 10 falls on the annular surface near the center of the circular surface at the top of the catalyst bed, which is more conducive to the uniform distribution of the liquid in the catalyst bed. The edge of the base plate 5 is machined into a flange form, with the lower flange face sealing to the upper tube sheet flange of the reactor, and the upper flange face sealing to the upper end flange of the reactor. An appropriate distance is maintained between the first distributor 1 and the highest point of the bubble cap 4 on the base plate 5. Positioning pins are set on the lower surfaces of the upper tube sheet flange of the reactor and the second distributor flange to ensure that the downcomer 6 is completely aligned with the reaction tube 10 during installation. The downcomer 6 is 10-30mm higher than the surface of the base plate 5, depending on the feed flow rate and the allowable residence time of the liquid on the distribution plate. The downcomer 6 and the distribution plate can be welded or threaded (if threaded, ensure that the threads do not leak liquid). The key is to ensure that the upper openings of all downcomers 6 are on the same horizontal plane, so that when the liquid level accumulated on the distribution plate rises to the upper opening of the downcomer 6, it overflows into each downcomer 6 at the same flow rate.

[0022] Each downcomer 6 has its opening protruding from the base plate 5, and each opening is fitted with a bubble cap 4. The top of the bubble cap 4 is closed and concentrically positioned with the downcomer 6, while the bottom of the bubble cap 4 is open and installed opposite the upper end of the downcomer 6. The lower edge of the bubble cap 4 is 5-10 mm below the opening of the downcomer 6. A gap exists between the inner wall of the bubble cap 4 and the outer wall of the downcomer 6, and a gap also exists between the lower edge of the bubble cap 4 and the base plate 5. The distance between the inner wall of the bubble cap 4 and the outer wall of the downcomer 6, as well as the distance between the lower edge of the bubble cap 4 and the base plate 5, must ensure that liquid falling onto the base plate 5 overflows into the downcomer 6 through the flow cross-section formed by the two, preventing stagnation on the base plate 5. The bubble cap 4 is approximately 50 mm high and is welded to the downcomer 6 using a connecting rod. When designing the tubular reactor, the spacing of the reaction tubes 10 must take into account the spacing of the bubble caps 4, ensuring that the spacing of the downcomer 6 is appropriate and that the bubble caps 4 are kept at a suitable distance.

[0023] like Figure 3 As shown, the sidewall of the blister pack 4 has ventilation slots 7. These slots protrude 2-5mm from the outer surface of the blister pack 4 and are outwardly oriented. This design ensures that liquid falling onto the blister pack flows down the surface, avoiding the slots. Even if gas passes rapidly through the slots, it will not carry liquid into the downcomer, causing uneven liquid distribution. The bottom edge of the ventilation slots 7 is 5mm higher than the opening of the downcomer 6, ensuring that liquid falling onto the distribution plate will not directly splash into the downcomer.

[0024] The base plate 5 and the upper tube sheet 9 of the reactor are both horizontally arranged. The corresponding downcomer 6, narrow-bore tube 8, and reaction tube 10 are coaxially arranged. The downcomer 6, narrow-bore tube 8, and reaction tube 10 are perpendicular to the base plate. The opening of the downcomer 6 is 10-30mm above the base plate 5, and the openings of all downcomers 6 are on the same horizontal plane; the bottom outlet of the narrow-bore tube 8 is inserted into the reaction tube 10 by 5-10mm.

Claims

1. A liquid distributor suitable for a tubular reactor in an experimental setup, characterized in that, It includes a first distributor (1) and a second distributor (3) arranged vertically. The first distributor (1) has small holes (2) distributed on it. The second distributor (3) is located above the reactor upper tube plate (9) at the top of the reaction tube (10). The second distributor (3) includes a bottom plate (5). The bottom plate (5) is provided with a downcomer (6) corresponding to the reaction tube (10). The lower end of the downcomer (6) is connected to the corresponding reaction tube (10) through a narrowing tube (8).

2. The liquid distributor for a tubular reactor in a test apparatus as described in claim 1, characterized in that, The opening of each of the downcomers (6) protrudes from the bottom plate (5) and is provided with a bubble cap (4).

3. The liquid distributor for a tubular reactor in a test apparatus as described in claim 2, characterized in that, The lower edge of the blister (4) is 5-10 mm lower than the opening of the downcomer (6). There is a gap between the inner wall of the blister (4) and the outer wall of the downcomer (6). There is also a gap between the lower edge of the blister (4) and the base plate (5).

4. The liquid distributor for a tubular reactor in a test apparatus as described in claim 2, characterized in that, The sidewall of the blister (4) has ventilation strip holes (7).

5. The liquid distributor for a tubular reactor in a test apparatus as described in claim 4, characterized in that, The ventilation strip hole (7) protrudes from the side wall of the bubble cap (4), and the bottom edge of the ventilation strip hole (7) is 5mm higher than the opening of the downcomer (6).

6. The liquid distributor for a tubular reactor in a test apparatus as described in claim 5, characterized in that, The ventilation strip hole (7) protrudes 2-5mm from the outer surface of the blister (4) and is an outward structure.

7. The liquid distributor for a tubular reactor in a test apparatus as described in claim 1, characterized in that, The bottom plate (5) and the upper tube plate (9) of the reactor are both horizontally arranged.

8. The liquid distributor for a tubular reactor in a test apparatus as described in claim 1, characterized in that, The corresponding downcomer (6), narrow-diameter pipe (8), and reaction pipe (10) are coaxially arranged.

9. The liquid distributor for a tubular reactor in a test apparatus as described in claim 1, 7, or 8, characterized in that, The downcomer (6), the narrowing pipe (8), and the reaction pipe (10) are arranged perpendicular to the bottom plate.

10. The liquid distributor for a tubular reactor in a test apparatus as described in claim 1, characterized in that, The opening of the downcomer (6) is 10-30mm higher than the bottom plate (5), and the openings of all downcomers (6) are on the same horizontal plane; the bottom outlet of the narrow-diameter pipe (8) is inserted into the reaction pipe (10) by 5-10mm.

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