Hydrogen distribution system in low-load production period of hydrogen production device

Abstract

The utility model belongs to the field of hydrogenation reaction devices, and discloses a hydrogen distribution system in a low-load production period of a hydrogen production device. Comprising a low-pressure gas liquid separation tank, a low-pressure gas compressor, a raw material liquid separation tank, a raw material preheater, a medium-pressure gas water separation tank, a hydrogenation reactor, a desulfurization reactor and a converter. Aiming at the problems existing in the hydrogen distribution system during the low-load production period of the hydrogen production device, the hydrogen distribution system disclosed by the utility model is optimized, and the hydrogenation catalyst is prevented from losing activity due to over-high hydrogen distribution amount. When the device is in low-load operation, medium bias flow in a reformer tube is avoided by increasing the hydrogen distribution amount, and a hydrogen distribution line crossing a hydrogenation reactor is added, so that the activity of a hydrogenation catalyst is ensured, the refining effect is achieved, and the total feeding amount of a conversion inlet is increased through the hydrogen distribution amount.

Description

Technical Field

[0001] The utility model belongs to the field of hydrogenation reaction devices, and in particular relates to a hydrogen distribution system during low-load production of a hydrogen production device. Background Art

[0002] The hydrogenation of the device uses hydrogenation low-fraction gas and self-produced hydrogen. The purpose of hydrogenation is to use hydrogen as a reactant to participate in the hydrogenation reaction of the raw materials, that is, to hydrogenate the organic sulfur in the raw materials into inorganic sulfur and hydrogenate the olefins to saturate them, so as to meet the requirements for the use of the conversion catalyst. When natural gas is used as the raw material of the device, the amount of hydrogen in the raw material is generally controlled to be 10-20% (volume fraction) of the natural gas feed amount. Too low a hydrogenation amount is likely to cause incomplete hydrogenation reaction, and too high a hydrogenation amount is likely to cause the active components of the hydrogenation catalyst to be reduced to oxides, causing the catalyst to lose activity.

[0003] In order to optimize the balance of the hydrogen pipeline network, the hydrogen production unit often adjusts the production load to achieve a load operation below 30%, mainly by increasing the hydrogen dosage and water-carbon ratio to ensure that "the load of the unit is reduced without reducing the total feed volume at the conversion inlet" to avoid the medium bias in the conversion furnace tube. If the hydrogen dosage exceeds 30% of the natural gas feed volume, the excessively high hydrogen partial pressure will easily cause the active components of the hydrogenation catalyst to be reduced to oxides, causing the hydrogenation catalyst to lose its activity. Utility Model Content

[0004] In order to overcome the deficiencies of the prior art, the utility model provides a hydrogen distribution system for a hydrogen production device during low-load production. The hydrogen distribution system is optimized to solve the problems existing in the hydrogen distribution system during low-load production of the hydrogen production device, avoid the loss of activity of the hydrogenation catalyst due to excessive hydrogen distribution, and optimize the hydrogen distribution system. When the device is running at low load, the medium bias in the reformer tube is avoided by increasing the hydrogen distribution amount, and a hydrogen distribution line across the hydrogenation reactor is added, which ensures the activity of the hydrogenation catalyst and achieves a refining effect, and increases the total feed amount at the reforming inlet through the hydrogen distribution amount.

[0005] The above-mentioned purpose of the utility model is achieved through the following technical solutions: a hydrogen distribution system for a hydrogen production device during low-load production, comprising a low-gas liquid separator tank, a low-gas compressor, a raw material liquid separator tank, a raw material preheater, a medium-transformation gas water separator tank, a hydrogenation reactor, a desulfurization reactor, and a converter; a self-produced hydrogen pipeline, a low-gas pipeline, and a reforming hydrogen pipeline are connected to the low-gas liquid separator tank, and the low-gas liquid separator tank is also provided with a pipeline leading to one end of the low-gas compressor, and the pipeline at the other end of the low-gas compressor is divided into two routes, one of which is a first hydrogen distribution pipeline, and the first hydrogen distribution pipeline and the natural gas pipeline are connected to the raw material liquid separator tank together, and the raw material liquid separator tank is also provided with a pipeline leading to the raw material preheater a, and the raw material preheater a is also provided with a pipeline leading to the raw material preheater b, a medium-transformation The raw material preheater b is also provided with a steam inlet pipeline, a steam distribution pipeline leading to the converter, and a pipeline leading to the top of the hydrogenation reactor. The bottom of the hydrogenation reactor is provided with a pipeline leading to the top of the desulfurization reactor a, the bottom of the desulfurization reactor a is provided with a pipeline leading to the top of the desulfurization reactor b, and the bottom of the desulfurization reactor b is provided with a pipeline leading to the converter. The other route of the low-gas compressor is the second hydrogen distribution pipeline, and the second hydrogen distribution pipeline is connected to the pipeline from the desulfurization reactor b to the converter. The first hydrogen distribution pipeline is also provided with a branch reflux pipeline whose end point is the low-gas liquid separator tank, and the branch reflux pipeline is provided with a water cooler. The second hydrogen distribution pipeline is also provided with parallel hydrogen distribution filters a and b.

[0006] Furthermore, the volume ratio of the self-produced hydrogen entering the raw material separation tank through the first hydrogen distribution pipeline and the natural gas fed through the natural gas pipeline is (1-2):10.

[0007] Furthermore, the self-produced hydrogen pipeline and the low-gas pipeline are connected into one pipeline and then enter the low-gas liquid separator tank.

[0008] Furthermore, the pipeline from the low-gas-liquid separator tank to the low-gas-compressor runs from the top of the low-gas-liquid separator tank to the low-gas-compressor.

[0009] Furthermore, the first hydrogen distribution pipeline and the natural gas pipeline are connected into one pipeline and then enter the raw material separation tank.

[0010] Furthermore, the pipeline from the raw material separator tank to the raw material preheater a, the pipeline leads from the top of the raw material separator tank to the raw material preheater a.

[0011] Furthermore, the steam introduced into the steam inlet pipeline is 3.5MPa steam.

[0012] Furthermore, the steam distribution pipeline is a pipeline leading from the desulfurization reactor b to the converter.

[0013] Compared with the prior art, the utility model has the following beneficial effects: it aims at the problems existing in the hydrogen distribution system during the low-load production of the hydrogen production device, avoids the loss of activity of the hydrogenation catalyst due to excessive hydrogen distribution, and optimizes the hydrogen distribution system. When the device is running at a low load, the medium bias in the reformer tube is avoided by increasing the hydrogen distribution amount, and a hydrogen distribution line across the hydrogenation reactor is added, which ensures the activity of the hydrogenation catalyst and achieves the refining effect, and increases the total feed amount of the reforming inlet by hydrogen distribution. During the low-load period of the hydrogen production device, the natural gas feed is 4000-6000Nm 3 / h, steam 25-35t / h, water-carbon ratio 6-9, hydrogen 4000-7000Nm 3 / h, of which the first route is hydrogen 500-1500Nm 3 / h, the second hydrogen supply is 4000-6000Nm 3 / h, the production load is only 20-30%, the medium flow rate in the reformer tube is 7-9m / s (when the device is 50% loaded, the medium flow rate in the furnace tube is 7-95m / s), the device has been in production and operation for 3 months, and no red tube and spot phenomenon occurs due to the medium deviation in the reformer tube, the production operation is stable, and the product quality is qualified. The present invention realizes the low-load long-term stable operation of the hydrogen production device and improves the operation flexibility of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below in conjunction with the accompanying drawings and specific implementations.

[0015] Figure 1 It is a system diagram of the hydrofining process flow of the prior art;

[0016] Figure 2 It is a structural diagram of the hydrogen distribution system of the utility model hydrogen production device during low-load production.

[0017] In the figure, 1. self-produced hydrogen pipeline; 2. low-gas pipeline; 3. low-gas liquid separator tank; 4. low-gas compressor; 5. first hydrogen distribution pipeline; 6. natural gas pipeline; 7. raw material liquid separator tank; 8. raw material preheater a; 9. raw material preheater b; 10. hydrogenation reactor; 11. desulfurization reactor a; 12. desulfurization reactor b; 13. converter; 14. medium-gas inlet pipeline; 15. medium-gas water separator tank; 16. steam inlet pipeline; 17. steam distribution pipeline; 18. second hydrogen distribution pipeline; 19. reforming hydrogen pipeline; 20. water cooler; 21. hydrogen distribution filter a; 22. hydrogen distribution filter b. DETAILED DESCRIPTION

[0018] The present invention is described in detail below through specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0019] Example 1

[0020] A hydrogen distribution system for a hydrogen production device during low-load production, comprising a low-gas liquid separator tank, a low-gas compressor, a raw material liquid separator tank, a raw material preheater, a medium-gas water separator tank, a hydrogenation reactor, a desulfurization reactor, and a converter; a self-produced hydrogen pipeline, a low-gas pipeline, and a reformed hydrogen pipeline are connected to the low-gas liquid separator tank, and the low-gas liquid separator tank is provided with another pipeline leading to one end of the low-gas compressor, and the pipeline at the other end of the low-gas compressor is divided into two routes, one of which is a first hydrogen distribution pipeline, and the first hydrogen distribution pipeline and the natural gas pipeline are connected to the raw material liquid separator tank together, and the raw material The liquid separation tank is also provided with a pipeline leading to the raw material preheater a. The raw material preheater a is also provided with a pipeline leading to the raw material preheater b, a medium-gas inlet pipeline, and a pipeline leading to the medium-gas water separation tank. The raw material preheater b is also provided with a steam inlet pipeline, a steam distribution pipeline leading to the converter, and a pipeline leading to the top of the hydrogenation reactor. The bottom of the hydrogenation reactor is provided with a pipeline leading to the top of the desulfurization reactor a. The bottom of the desulfurization reactor a is provided with a pipeline leading to the top of the desulfurization reactor b. The bottom of the desulfurization reactor b is provided with a pipeline leading to the converter. The low-gas compressor The other is the second hydrogen distribution pipeline, which is connected to the pipeline from the desulfurization reactor b to the converter. The first hydrogen distribution pipeline is also provided with a branch return pipeline whose terminal is the low-gas separation tank. The branch return pipeline is provided with a water cooler. The second hydrogen distribution pipeline is also provided with a parallel hydrogen distribution filter a and a hydrogen distribution filter b; the volume ratio of the self-produced hydrogen entering the raw material separation tank through the first hydrogen distribution pipeline to the natural gas fed by the natural gas pipeline is (1-2):10; the self-produced hydrogen pipeline and the low-gas pipeline are parallel to form one line. The pipeline enters the low-gas separation tank after the low-gas separation tank; the pipeline from the low-gas separation tank to the low-gas compressor, the pipeline leads from the top of the low-gas separation tank to the low-gas compressor; the first hydrogen distribution pipeline and the natural gas pipeline are paralleled into one pipeline and then enter the raw material separation tank; the pipeline from the raw material separation tank to the raw material preheater a, the pipeline leads from the top of the raw material separation tank to the raw material preheater a; the steam introduced into the steam inlet pipeline is 3.5MPa steam; the steam distribution pipeline is a pipeline leading to the desulfurization reactor b to the converter.

[0021] The hydrogen distribution system of the hydrogen production unit has been modified to add a hydrogen distribution line from the outlet of the low-gas compressor to the outlet of the desulfurization reactor. That is, the hydrogen is distributed in two ways. The first way is mixed with the raw material and enters the hydrogenation reactor, and the second way is mixed with the desulfurized raw material and enters the converter.

[0022] During the low load period of the 50,000 Nm3 / h hydrogen production unit of Jinxi Petrochemical Branch, the natural gas feed is 4000-6000Nm 3 / h, steam 25-35t / h, water-carbon ratio 6-9, hydrogen 4000-7000Nm 3 / h, of which the first route is hydrogen 500-1500Nm 3 / h, the second route hydrogen distribution 4000-6000m 3 / h, the production load is only 20-30%, the medium flow rate in the converter tube is 7-9m / s, which is higher than the medium flow rate in the tube when the device is 50% loaded. The device has been in production and operation for 3 months, and there has been no red tube and spotting due to the deviation of the medium in the converter tube. The production operation is stable and the product quality is qualified.

[0023] Table 1 Main operating parameters of the hydrogen distribution system of the present invention at 20-30% load and the original system data at 50.00% load

[0024]

[0025]

[0026] The above-mentioned embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made to the present invention without departing from the principle and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. A hydrogen distribution system for a hydrogen production device during low-load production, characterized in that: The invention comprises a low-gas liquid separator tank (3), a low-gas compressor (4), a raw material liquid separator tank (7), a raw material preheater, a medium-gas water separator tank (15), a hydrogenation reactor (10), a desulfurization reactor, and a reforming furnace (13); a self-generated hydrogen pipeline (1), a low-gas pipeline (2) and a reforming hydrogen pipeline (19) are connected to the low-gas liquid separator tank (3); the low-gas liquid separator tank (3) is also provided with a pipeline connected to one end of the low-gas compressor (4); the low-gas compressor (4 ) The other end of the pipeline is divided into two routes, one of which is a first hydrogen distribution pipeline (5). The first hydrogen distribution pipeline (5) and the natural gas pipeline (6) are connected to the raw material separation tank (7). The raw material separation tank (7) is also provided with a pipeline leading to the raw material preheater a (8). The raw material preheater a (8) is also provided with a pipeline leading to the raw material preheater b (9), a medium-transformation gas inlet pipeline (14), and a pipeline leading to the medium-transformation gas water separation tank (15). The raw material preheater b ( 9) is also provided with a steam inlet pipeline (16), a steam distribution pipeline (17) leading to the reformer (13), and a pipeline leading to the top of the hydrogenation reactor (10); a pipeline leading to the top of the desulfurization reactor a (11) is provided at the bottom of the hydrogenation reactor (10); a pipeline leading to the top of the desulfurization reactor b (12) is provided at the bottom of the desulfurization reactor a (11); a pipeline leading to the top of the desulfurization reactor b (12) is provided at the bottom of the desulfurization reactor b (12); a pipeline leading to the reformer (13) is provided at the bottom of the desulfurization reactor b (12); the other route of the low-gas compressor (4) is a second hydrogen distribution pipeline (18); the second hydrogen distribution pipeline (18) is connected to the pipeline from the desulfurization reactor b (12) to the reformer (13); the first hydrogen distribution pipeline (5) is also provided with a branch reflux pipeline whose terminal is the low-gas liquid separator (3); a water cooler (20) is provided on the branch reflux pipeline; and the second hydrogen distribution pipeline (18) is also provided with a hydrogen distribution filter a (21) and a hydrogen distribution filter b (22) connected in parallel.

2. The hydrogen distribution system during low-load production of a hydrogen production device according to claim 1, characterized in that: The first hydrogen distribution pipeline (5) and the natural gas pipeline (6) are connected to the raw material separation tank (7) together, and the volume ratio of the self-produced hydrogen entering the raw material separation tank (7) through the first hydrogen distribution pipeline (5) to the natural gas fed through the natural gas pipeline (6) is (1-2):

10.

3. The hydrogen distribution system during low-load production of a hydrogen production device according to claim 1, characterized in that: The self-generated hydrogen pipeline (1) and the low-gas pipeline (2) are connected in parallel to form one pipeline and then enter the low-gas liquid separation tank (3).

4. The hydrogen distribution system during low-load production of a hydrogen production device according to claim 1, characterized in that: The pipeline from the low-gas-liquid separator tank (3) to the low-gas-compressor (4) is connected to the low-gas-compressor (4), and the pipeline runs from the top of the low-gas-liquid separator tank (3) to the low-gas-compressor (4).

5. The hydrogen distribution system during low-load production of a hydrogen production device according to claim 1, characterized in that: The first hydrogen distribution pipeline (5) and the natural gas pipeline (6) are connected in parallel to form one pipeline and then enter the raw material separation tank (7).

6. The hydrogen distribution system during low-load production of a hydrogen production device according to claim 1, characterized in that: The pipeline from the raw material liquid separation tank (7) to the raw material preheater a (8) is connected to the raw material preheater a (8) from the top of the raw material liquid separation tank (7).

7. The hydrogen distribution system for the hydrogen production device during low-load production according to claim 1, characterized in that: The steam introduced into the steam inlet pipeline (16) is 3.5 MPa steam.

8. The hydrogen distribution system for the hydrogen production device during low-load production according to claim 1, characterized in that: The steam distribution pipeline (17) is a pipeline leading from the desulfurization reactor b (12) to the reformer (13).

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