Hydrogen preparation desulfurization device and desulfurization method

Abstract

The invention relates to the technical field of hydrogen production equipment, in particular to a hydrogen preparation desulfurization device and a desulfurization method. According to the hydrogen preparation desulfurization device, a gas supply mechanism is connected with a gas-liquid separation tower for separating liquid in gas; the gas absorption mechanism comprises an absorption tower for absorbing H2S in gas, and a gas inlet of the absorption tower is communicated with a gas outlet of the gas-liquid separation tower; the absorption tower is filled with a catalyst which chemically reacts with H2S; the regeneration mechanism comprises a regeneration tower, the regeneration tower is communicated with the absorption tower, and the regeneration tower is connected with a feeding mechanism for reducing a solution in the absorption tower; the sulfur recovery mechanism comprises a filter for filtering elemental sulfur generated by the regeneration tower, a liquid inlet of the filter is communicated with the bottom of the regeneration tower, and a liquid outlet of the filter is communicated with the upper part of the side part of the regeneration tower through a first infusion pump, so that the elemental sulfur in the natural gas is recycled, and a catalyst can be regenerated and recycled; and energy waste is effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production equipment, and in particular to a hydrogen preparation and desulfurization device and a desulfurization method. Background Art

[0002] Hydrogen is a highly flammable, colorless, transparent, odorless and tasteless gas. Hydrogen is the smallest known gas in the world, with a density of only 1 / 14 of that of air, that is, at 0°C and a standard atmospheric pressure, the density of hydrogen is 0.0899 g / L, so hydrogen can be used as a filling gas for airships and hydrogen balloons. Hydrogen is a substance with the smallest relative molecular mass and has a strong reducing property, and is often used as a reducing agent in chemical reactions.

[0003] Since hydrogen has a wide range of uses in industry, there are currently five general methods for producing hydrogen in industry: 1. Hydrogen produced by methanol cracking; 2. Hydrogen produced by water gas; 3. Hydrogen produced by electrolysis of water; 4. Hydrogen produced by electrolysis of salt water in the chlor-alkali industry; 5. Hydrogen produced by natural gas. Among them, the use of methanol cracking to produce hydrogen is toxic and can easily cause occupational health hazards to production workers; a large amount of CO is present in the production process of hydrogen produced by water gas, and as we all know, CO is a highly toxic substance that can easily cause poisoning and death; the production of hydrogen by electrolysis of water consumes a lot of energy, and under high energy consumption, half of the product oxygen is directly or indirectly discharged into the atmosphere, causing energy loss; the production of hydrogen by electrolysis of salt water in the chlor-alkali industry requires high investment and high energy consumption, with an investment of more than 1 billion yuan or even several billion yuan, which is not suitable for the flexible and light production and use of hydrogen; therefore, the process technology of producing hydrogen from natural gas has been favored by more and more hydrogen producers.

[0004] Since the raw natural gas contains a small amount of sulfides, mainly H2S, organic sulfur components such as COS, CS2, mercaptan, and sulfide exist in some raw natural gas, and even exceed the content of H2S, most of the sulfides in the raw natural gas need to be removed in the process of producing hydrogen from natural gas. However, the existing desulfurization devices have problems such as low desulfurization efficiency, unclean desulfurization, and energy waste. Summary of the invention

[0005] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art and to provide a hydrogen preparation desulfurization device and a desulfurization method.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows: a hydrogen preparation and desulfurization device, comprising

[0007] A gas supply mechanism, wherein the gas supply mechanism is connected to a gas-liquid separation tower for separating liquid from gas;

[0008] A gas absorption mechanism, the gas absorption mechanism comprising an absorption tower for absorbing H2S in the gas, the gas inlet of the absorption tower being connected to the gas outlet of the gas-liquid separation tower; the absorption tower is filled with a catalyst that chemically reacts with H2S;

[0009] A regeneration mechanism, the regeneration mechanism comprising a regeneration tower, the regeneration tower being connected to the absorption tower, and the regeneration tower being connected to a feeding mechanism for reducing the solution in the absorption tower;

[0010] A sulfur recovery mechanism includes a filter for filtering sulfur generated by the regeneration tower, wherein the liquid inlet of the filter is connected to the bottom of the regeneration tower, and the liquid outlet of the filter is connected to the upper side of the regeneration tower through a first liquid pump.

[0011] Furthermore, it also includes a flash tank, which is installed on the side of the absorption tower and is used to separate organic gas in the solution; the bottom of the flash tank is connected to the regeneration tower.

[0012] Furthermore, a first stirring member is installed in the absorption tower, and the first stirring member includes a first motor installed outside the absorption tower, and a first rotating shaft is provided at the output end of the first motor, and a first stirring blade is installed on the first rotating shaft.

[0013] Furthermore, a second stirring member is installed in the regeneration tower, and the second stirring member includes a second motor installed outside the regeneration tower. A second rotating shaft is provided at the output end of the second motor, and a second stirring blade is installed on the second rotating shaft.

[0014] Furthermore, a slurry pump is installed between the regeneration tower and the filter, and one end of the liquid outlet of the slurry pump is connected to the liquid inlet of the filter; and the other end is connected to the bottom of the regeneration tower.

[0015] Furthermore, the bottom of the regeneration tower is conical.

[0016] Furthermore, a second liquid pump is connected above the regeneration tower, and a liquid outlet of the second liquid pump is communicated with the absorption tower, so as to pump the catalyst in the regeneration tower back to the absorption tower for recycling.

[0017] Furthermore, the feeding mechanism includes a regeneration fan, which is connected to the regeneration tower and is used to inject oxygen into the regeneration tower to oxidize the solution in the regeneration tower.

[0018] Furthermore, it also includes a reagent replenishing mechanism, which is installed on the side of the absorption tower and is used to add catalyst into the absorption tower.

[0019] A desulfurization method for a hydrogen preparation desulfurization device, using the above-mentioned hydrogen preparation desulfurization device, the desulfurization method is as follows:

[0020] S1: The raw natural gas is supplied to the gas-liquid separation tower through the gas supply mechanism for gas-liquid separation. After gas-liquid separation, the gas enters the absorption tower and undergoes H2S oxidation reaction with the catalyst in the absorption tower. During the oxidation reaction, H2S is oxidized to elemental sulfur. After a period of reaction, the gas is cooled and liquid-separated to separate the droplets entrained in the gas and then sent to the hydrogen production equipment;

[0021] S2, the catalyst that has absorbed H2S and the elemental sulfur generated by the reaction are sent to the flash tank through the pressure difference. The flash pressure is controlled at 0.20-0.30MPa. Under this pressure condition, the organic gas in the catalyst is flashed and separated. The catalyst and the elemental sulfur after flashing enter the regeneration tower for solution regeneration and separation of elemental sulfur.

[0022] S3. In the regeneration tower, the catalyst from the flash tank fully contacts and reacts with the oxygen blown in by the regeneration blower. After multi-stage oxidation, the catalyst is oxidized. During the oxidation process, the sulfur element also agglomerates, which increases the particle size of the solid particles and enters the sedimentation tank.

[0023] S4. Separate the regenerated catalyst and sulfur from the regeneration tower. The separated sulfur catalyst is sent back to the absorption tower for cyclic absorption through the second pumping pump. The sulfur at the bottom of the regeneration tower is sent to the filter of the sulfur recovery mechanism through the sulfur slurry pump for solid-liquid separation. After separation, the liquid is pumped back to the regeneration tower by the first pumping pump to recycle the catalyst.

[0024] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0025] 1. This application realizes the recovery and utilization of sulfur in natural gas by setting up a gas supply mechanism, a gas absorption mechanism, a regeneration mechanism, and a sulfur recovery mechanism, and the catalyst can be regenerated and recycled, effectively avoiding energy waste.

[0026] 2. The process of the present application is simple, and the one-step treatment process can quickly oxidize hydrogen sulfide directly into elemental sulfur, with high efficiency in removing sulfur.

[0027] 3. The operating cost of this application is low, because the catalysts in various reagents used in the desulfurization process can be regenerated and recycled without side reactions, and only a small amount of catalyst lost in the desulfurization process needs to be supplemented.

[0028] 4. The catalyst of the present application has high selectivity, and almost no secondary salt is generated and waste liquid is discharged. In the catalytic desulfurization, the catalyst oxidizes hydrogen sulfide to sulfur element, and the desulfurization process has few side reactions; it is non-toxic and harmless to the environment and human body, and has good environmental benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the structure of a hydrogen preparation and desulfurization device in a preferred embodiment of the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of an absorption tower in a preferred embodiment of the present invention;

[0031] Figure 3 It is a schematic diagram of the structure of the regeneration tower in a preferred embodiment of the present invention.

[0032] Figure numerals: 1. air supply mechanism; 2. gas-liquid separation tower; 3. absorption tower; 4. regeneration tower; 5. feeding mechanism; 6. filter; 7. first liquid pump; 8. flash tank; 9. first stirring member; 901. first motor; 902. first rotating shaft; 903. first stirring blade; 10. second stirring member; 1001. second motor; 1002. second rotating shaft; 1003. second stirring blade; 11. slurry pump; 12. second liquid pump; 13. reagent replenishing mechanism. DETAILED DESCRIPTION

[0033] The technical solutions in the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0034] Reference Figure 1-Figure 3 As shown, a preferred embodiment of the present invention, a hydrogen preparation desulfurization device, comprising

[0035] A gas supply mechanism 1, wherein the gas supply mechanism 1 is connected to a gas-liquid separation tower 2 for separating liquid from gas;

[0036] A gas absorption mechanism, the gas absorption mechanism comprises an absorption tower 3 for absorbing H2S in the gas, the air inlet of the absorption tower 3 is connected to the air outlet of the gas-liquid separation tower 2; the absorption tower 3 is filled with a catalyst that reacts chemically with H2S;

[0037] A regeneration mechanism, the regeneration mechanism comprising a regeneration tower 4, the regeneration tower 4 is connected to the absorption tower 3, and the regeneration tower 4 is connected to a feeding mechanism 5 for reducing the solution in the absorption tower 3;

[0038] The sulfur recovery mechanism includes a filter 6 for filtering the sulfur generated by the regeneration tower 4, the liquid inlet of the filter 6 is connected to the bottom of the regeneration tower 4, and the liquid outlet of the filter 6 is connected to the upper side of the regeneration tower 4 through a first liquid pump 7, thereby realizing the recovery of the sulfur in the natural gas, and the catalyst can be regenerated and recycled, effectively avoiding the waste of energy.

[0039] As a preferred embodiment of the present invention, it may also have the following additional technical features: it also includes a flash tank 8, which is installed on the side of the absorption tower 3 and is used to separate the organic gas in the solution; the bottom of the flash tank 8 is connected to the regeneration tower 4. In this way, the organic gas in the catalyst can be separated, and the gas is a small amount of light hydrocarbon gas, which can be directly burned as fuel after flashing out to provide energy for the desulfurization device.

[0040] In this embodiment, a first stirring member 9 is installed in the absorption tower 3, and the first stirring member 9 includes a first motor 901 installed outside the absorption tower 3, and the output end of the first motor 901 is provided with a first rotating shaft 902 extending into the absorption tower, and a first stirring blade 903 is installed on the first rotating shaft 902. In this way, the reaction process can be accelerated, so that the natural gas can fully react with the catalyst.

[0041] In this embodiment, a second stirring member 10 is installed in the regeneration tower 4, and the second stirring member 10 includes a second motor 1001 installed on the outside of the regeneration tower 4, and the output end of the second motor 1001 is provided with a second rotating shaft 1002 extending into the interior of the regeneration tower, and a second stirring blade 1003 is installed on the second rotating shaft 1002; and the feeding mechanism 5 includes a regeneration fan, which is connected to the regeneration tower 4 and is used to inject oxygen into the regeneration tower 4 to oxidize the solution in the regeneration tower, thereby allowing the catalyst to be fully regenerated and effectively reducing the production cost of hydrogen production.

[0042] In this embodiment, a slurry pump 11 is installed between the regeneration tower 4 and the filter 6, and one end of the liquid outlet of the slurry pump 11 is connected to the liquid inlet of the filter 6; the other end is connected to the bottom of the regeneration tower 4. That is, the liquid outlet of the slurry pump 11 is divided into two paths, one of which returns to the conical bottom of the regeneration tower for circulation disturbance to prevent sulfur deposition and blockage; the other path is sent to the filter 6 for separation to obtain sulfur with a solid content of 65% and clean catalyst filtrate, and the separated filtrate is recovered to the regeneration tower through the filtrate pump; the sulfur paste with a solid content greater than 65% can be dragged out of the factory as a raw material for the adjacent acid plant, and can also be melted and refined to obtain industrial qualified sulfur (sulfur content greater than or equal to 99wt%) after the separated sulfur paste, and the user can choose according to the actual situation (this solution is designed according to the output of sulfur paste with a solid content greater than 65%).

[0043] In this embodiment, the bottom of the regeneration tower 4 is conical, so that it is convenient to discharge the material.

[0044] In this embodiment, a second liquid pump 12 is connected above the regeneration tower 4, and the liquid outlet of the second liquid pump 12 is connected to the absorption tower 3, which is used to pump the catalyst in the regeneration tower 4 back to the absorption tower 3 for recycling, thereby realizing the recycling of resources, effectively avoiding waste of resources, and reducing operating production costs.

[0045] In this embodiment, a reagent replenishing mechanism 13 is also included, and the reagent replenishing mechanism 13 is installed on the side of the absorption tower 3, and is used to add catalyst into the absorption tower 3. Because the catalyst will be consumed during the desulfurization process, it is necessary to replenish fresh catalyst in time to prevent the effective composition in the whole system from changing significantly, thereby ensuring the maximum desulfurization effect.

[0046] A desulfurization method for a hydrogen preparation desulfurization device, using the above-mentioned hydrogen preparation desulfurization device, the desulfurization method is as follows:

[0047] S1: The raw natural gas is supplied to the gas-liquid separation tower 2 through the gas supply mechanism 1 for gas-liquid separation. After the gas-liquid separation, the gas enters the absorption tower 3, and undergoes H2S oxidation reaction with the catalyst in the absorption tower 3. During the oxidation reaction, H2S is oxidized to elemental sulfur. After a period of reaction, the gas is cooled and liquid-separated to separate the droplets entrained in the gas and then sent to the hydrogen production equipment;

[0048] S2, the catalyst that has absorbed H2S and the elemental sulfur generated by the reaction are sent to the flash tank 8 through the pressure difference. The flash pressure is controlled at 0.20-0.30 MPa. Under this pressure condition, the organic gas in the catalyst is flashed and separated. The catalyst and the elemental sulfur after flashing enter the regeneration tower 4 for solution regeneration and separation of elemental sulfur.

[0049] S3, in the regeneration tower 4, the catalyst from the flash tank 8 fully contacts and reacts with the oxygen blown in by the regeneration blower, and the catalyst is oxidized through multi-stage oxidation. During the oxidation process, the sulfur element also agglomerates, and the particle size of the solid particles increases and enters the sedimentation tank;

[0050] S4. Separate the regenerated catalyst and sulfur from the regeneration tower. The separated sulfur catalyst is sent back to the absorption tower through the second pumping pump for cyclic absorption. The sulfur at the bottom of the regeneration tower is sent to the filter of the sulfur recovery mechanism through the sulfur slurry pump for solid-liquid separation. The separated liquid is used to pump the catalyst back to the regeneration tower through the first pumping pump for recycling, thereby realizing a one-step method to quickly oxidize hydrogen sulfide directly into sulfur. The sulfur removal efficiency is high, and the process is simple, the operating cost is low, it is non-toxic and harmless to the environment and human body, and it has good environmental benefits.

[0051] Under the premise that no conflict occurs, those skilled in the art may freely combine and superimpose the above-mentioned additional technical features.

[0052] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A hydrogen preparation and desulfurization device, characterized in that: include A gas supply mechanism, wherein the gas supply mechanism is connected to a gas-liquid separation tower for separating liquid from gas; A gas absorption mechanism, the gas absorption mechanism comprising an absorption tower for absorbing H2S in the gas, the gas inlet of the absorption tower being connected to the gas outlet of the gas-liquid separation tower; the absorption tower is filled with a catalyst that chemically reacts with H2S; A regeneration mechanism, the regeneration mechanism comprising a regeneration tower, the regeneration tower being connected to the absorption tower, and the regeneration tower being connected to a feeding mechanism for reducing the solution in the absorption tower; A sulfur recovery mechanism includes a filter for filtering sulfur generated by the regeneration tower, wherein the liquid inlet of the filter is connected to the bottom of the regeneration tower, and the liquid outlet of the filter is connected to the upper side of the regeneration tower through a first liquid pump.

2. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: It also includes a flash tank, which is installed on the side of the absorption tower and is used to separate organic gas in the solution; the bottom of the flash tank is connected to the regeneration tower.

3. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: A first stirring member is installed in the absorption tower. The first stirring member includes a first motor installed outside the absorption tower. A first rotating shaft is provided at an output end of the first motor. A first stirring blade is installed on the first rotating shaft.

4. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: A second stirring member is installed in the regeneration tower. The second stirring member includes a second motor installed outside the regeneration tower. A second rotating shaft is provided at the output end of the second motor. A second stirring blade is installed on the second rotating shaft.

5. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: A slurry pump is installed between the regeneration tower and the filter, one end of the liquid outlet of the slurry pump is connected to the liquid inlet of the filter; and the other end is connected to the bottom of the regeneration tower.

6. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: The bottom of the regeneration tower is conical.

7. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: A second liquid pump is connected above the regeneration tower, and a liquid outlet of the second liquid pump is communicated with the absorption tower for pumping the catalyst in the regeneration tower back to the absorption tower for recycling.

8. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: The feeding mechanism comprises a regeneration fan, which is connected to the regeneration tower and is used for injecting oxygen into the regeneration tower to oxidize the solution in the regeneration tower.

9. The hydrogen preparation and desulfurization device according to claim 1, characterized in that: It also includes a reagent replenishing mechanism, which is installed on the side of the absorption tower and is used to add catalyst into the absorption tower.

10. A desulfurization method for a hydrogen preparation desulfurization device, characterized in that: The hydrogen preparation and desulfurization device according to any one of claims 1 to 9 is used, and the desulfurization method is as follows: S1: The raw natural gas is supplied to the gas-liquid separation tower through the gas supply mechanism for gas-liquid separation. After gas-liquid separation, the gas enters the absorption tower and undergoes H2S oxidation reaction with the catalyst in the absorption tower. During the oxidation reaction, H2S is oxidized to elemental sulfur. After a period of reaction, the gas is cooled and liquid-separated to separate the droplets entrained in the gas and then sent to the hydrogen production equipment; S2, the catalyst that has absorbed H2S and the elemental sulfur generated by the reaction are sent to the flash tank through the pressure difference. The flash pressure is controlled at 0.20-0.30MPa. Under this pressure condition, the organic gas in the catalyst is flashed and separated. The catalyst and the elemental sulfur after flashing enter the regeneration tower for solution regeneration and separation of elemental sulfur. S3. In the regeneration tower, the catalyst from the flash tank fully contacts and reacts with the oxygen blown in by the regeneration blower. After multi-stage oxidation, the catalyst is oxidized. During the oxidation process, the sulfur element also agglomerates, which increases the particle size of the solid particles and enters the sedimentation tank. S4. Separate the regenerated catalyst and sulfur from the regeneration tower. The separated sulfur catalyst is sent back to the absorption tower for cyclic absorption through the second pumping pump. The sulfur at the bottom of the regeneration tower is sent to the filter of the sulfur recovery mechanism through the sulfur slurry pump for solid-liquid separation. After separation, the liquid is pumped back to the regeneration tower by the first pumping pump to recycle the catalyst.

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