Device and method for preparing hydrogen and sulfur through continuous reaction of hydrogen sulfide

Abstract

The invention provides a device and a method for preparing hydrogen and sulfur through continuous reaction of hydrogen sulfide. The device comprises a gas distribution unit, a reaction unit and a tail gas absorption unit, wherein the reaction unit comprises at least two reaction tubes and at least two sulfur traps which are sequentially and alternately communicated, and a reaction heater for heating the reaction tubes; an outlet of the gas distribution unit is connected with an inlet of the first reaction tube, and an outlet of the last sulfur trap is connected with an inlet of the tail gas absorption unit. The hydrogen sulfide thermal catalytic decomposition method, the sulfur condensation recovery and the hydrogen sulfide and hydrogen separation process are combined, hydrogen sulfide is subjected to catalytic thermal decomposition into elemental sulfur and hydrogen, the conversion rate of hydrogen sulfide is increased through condensation, high-added-value sulfur is produced, and meanwhile hydrogen resources with the higher added value are recovered.

Description

Technical Field

[0001] The invention relates to the technical field of hydrogen sulfide treatment, and in particular to a device and method for producing hydrogen and sulfur through continuous reaction of hydrogen sulfide. Background Art

[0002] Hydrogen sulfide is a highly toxic, foul-smelling acidic gas that not only harms human health, but also causes corrosion of metals and other materials, damage to the environment, and causes ecological pollution and economic waste. Hydrogen sulfide exists in the natural raw materials (natural gas, crude oil and coal) of energy production. Therefore, the large amount of hydrogen sulfide gas produced in the energy production process must be treated harmlessly on site.

[0003] At present, the Claus process is the main technical route for hydrogen sulfide treatment. Hydrogen sulfide is converted into elemental sulfur for recovery through the high-temperature reaction section of the main combustion furnace and the low-temperature catalytic reaction section. This process method successfully solves the problem of hydrogen sulfide treatment in the energy production process. In the high-temperature combustion section of this process, hydrogen sulfide burns to generate sulfur dioxide. With the continuous improvement and development of Claus and its extended processes in equipment, instruments and catalysts, the total sulfur recovery rate continues to increase, and the emission concentration of sulfur dioxide in the tail gas is gradually decreasing. However, limited by the chemical equilibrium at the Claus reaction temperature, even if the equipment and operating conditions are good, the sulfur recovery rate of the Claus extended process is only slightly higher than 99%, resulting in 0.7%-1% of the sulfur in the tail gas being discharged into the atmosphere in the form of incineration into sulfur dioxide. Therefore, the sulfur recovery device needs to add a tail gas treatment device to meet the emission standards specified by the national standard. From the perspective of atomic economy, the Claus process recovers sulfur, but converts precious hydrogen resources into water. Direct cracking of hydrogen sulfide can shorten the Claus process flow, recover sulfur while obtaining hydrogen source, and have a high reaction atom utilization rate. At present, there are many research methods for direct cracking of hydrogen sulfide, such as: thermal decomposition (direct high-temperature decomposition, superadiabatic decomposition, catalytic thermal decomposition), electrochemical decomposition, photocatalytic decomposition, plasma decomposition, etc.

[0004] Among them, the process of electrolyzing hydrogen sulfide to produce hydrogen and sulfur is simple, the operating conditions are mild, the primary absorption rate of hydrogen sulfide is high, and it is insensitive to the content of hydrogen sulfide in the raw gas. However, there are some constraints, such as the absorption liquid is corrosive to the equipment and causes environmental pollution; the generated sulfur is of low purity and difficult to separate; it is difficult to develop electrode materials with reasonable price, long service life and excellent performance and reasonably designed electrolysis devices. Photocatalysis and photoelectrocatalysis use cheap and abundant solar energy as an energy source, with mild reaction conditions and low energy consumption, but this method has the disadvantages of low photon utilization efficiency, high preparation cost of visible light responsive catalysts, difficulty in recycling, and easy photocorrosion and poisoning of catalysts. Plasma decomposition of hydrogen sulfide can make hydrogen sulfide excited, dissociated and ionized at a lower temperature to obtain a higher conversion rate; however, this method mainly focuses on the design of plasma reactors and the optimization of discharge parameters, and the generated elemental sulfur is difficult to recover and has high energy consumption. Thermal decomposition refers to a method that uses heat to provide energy for hydrogen sulfide bond breaking. The process is simple and convenient, but the reaction is limited by thermodynamics. The reaction of hydrogen sulfide cracking into hydrogen and sulfur can only be carried out under high temperature conditions. When the temperature is 1000℃ and 1200℃, the conversion rate of hydrogen sulfide is only 20% and 38% respectively; when the temperature exceeds 1375℃, the conversion rate of hydrogen sulfide can reach more than 50%. This process requires a large amount of heat and high energy consumption. Since it is difficult to achieve a high hydrogen sulfide conversion rate by direct thermal decomposition, attempts are made to promote the conversion of hydrogen sulfide by changing conditions and removing products to cause chemical equilibrium shifts to obtain a higher conversion rate. Summary of the invention

[0005] In order to solve the above technical problems, the object of the present invention is to provide a device and method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, so as to improve the yield of the product under mild reaction conditions.

[0006] To achieve the above-mentioned purpose, the present invention provides a device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which comprises a gas distribution unit, a reaction unit, and a tail gas absorption unit;

[0007] Wherein, the reaction unit comprises at least two reaction tubes and at least two sulfur traps which are alternately connected in sequence, and a reaction heater for heating the reaction tubes;

[0008] The outlet of the gas distribution unit is connected to the inlet of the first reaction tube, and the outlet of the last sulfur trap is connected to the inlet of the tail gas absorption unit.

[0009] The present invention combines the hydrogen sulfide thermal catalytic decomposition method, sulfur condensation recovery and hydrogen sulfide hydrogen separation process, catalytically decomposes hydrogen sulfide into elemental sulfur and hydrogen, utilizes condensation to improve the hydrogen sulfide conversion rate, produces high value-added sulfur, and recovers hydrogen resources with higher added value at the same time.

[0010] In the above-mentioned device for continuously reacting hydrogen sulfide to produce hydrogen and sulfur, preferably, the tail gas absorption unit comprises a scrubbing bottle, a drying tube and a hydrogen absorption bottle connected in sequence; the inlet of the scrubbing bottle is connected to the outlet of the last sulfur trap.

[0011] In the above-mentioned device for continuously reacting hydrogen sulfide to produce hydrogen and sulfur, preferably, the gas distribution unit includes a hydrogen sulfide storage tank and a mixed gas tank body connected by a pipeline, and a gas flow meter is provided on the pipeline between the two. The gas flow meter is used to control the flow of hydrogen sulfide. The gas flow meter is required to be corrosion-resistant, and the maximum flow range is 0.1-10L / min. The gas distribution unit of the present invention is convenient for controlling the concentration of hydrogen sulfide in the mixed gas, and exploring the hydrogen sulfide concentration range applicable to the method of the present invention.

[0012] The mixed gas tank body of the present invention is made of hydrogen sulfide corrosion resistant material and comprises 2-5 air inlets. A sampling port is arranged behind the gas outlet of the tank body, about 3 cm away from the outlet end of the mixed gas tank body, the diameter of the sampling port is 3-6 mm, and the sampling port is connected to the gas outlet of the mixed gas tank body and the reaction tube through a three-way ferrule.

[0013] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the reaction unit comprises 3-6 reaction tubes.

[0014] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, a catalyst is installed in the reaction tube.

[0015] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, a catalyst is placed in each reaction tube starting from the second reaction tube. More preferably, a catalyst is placed in each reaction tube.

[0016] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the first reaction tube is an L-shaped reaction tube or an inverted U-shaped reaction tube; and each reaction tube from the second reaction tube onwards is an inverted U-shaped reaction tube.

[0017] In the above-mentioned device for continuously reacting hydrogen sulfide to produce hydrogen and sulfur, preferably, the width (a section with an inlet) of the L-shaped reaction tube is 15-30 cm, the length (a section with an outlet) is 30-80 cm, the inner diameter is 0.5-2 cm, and the outer diameter is 1-3 cm. Preferably, the width of the inverted U-shaped reaction tube is 15-60 cm, the length (platform section) is 30-80 cm, the inner diameter is 0.5-2 cm, and the outer diameter is 1-3 cm. A catalyst can be placed in the platform section of the inverted U-shaped reaction tube. The material of the reaction tube is a high temperature resistant material such as quartz and corundum.

[0018] In the above-mentioned device for producing hydrogen and sulfur through continuous reaction of hydrogen sulfide, preferably, the reaction tube is arranged inside the reaction heater.

[0019] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, a partition is provided in the sulfur trap. Adding a partition to the sulfur trap can improve the purity of the sulfur product.

[0020] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the sulfur collector is provided with an air inlet and an air outlet, the air inlet is connected to the outlet of the previous reaction tube, and the air outlet is connected to the next reaction tube.

[0021] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the number of sulfur collectors is the same as the number of reaction tubes.

[0022] In the present invention, the air inlet and outlet of the sulfur collector are connected to the reaction tube through a straight-through ferrule. A heating belt (high-temperature glass fiber heating belt) is provided on the pipeline between the sulfur collector and the reaction tube for heat preservation, with a width of 3-5 cm and a maximum temperature of 350° C. A sampling port is provided after the air outlet of the last sulfur collector, about 3 cm away from the outlet end of the sulfur collector tank body, and the diameter of the sampling port is 3-6 mm. The sampling port is connected to the air outlet of the sulfur collector tank body and the washing bottle through a three-way ferrule.

[0023] In the above-mentioned device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the device also includes pipelines, valves and automatic control instruments connecting the various units.

[0024] The device of the present invention can safely and reliably decompose hydrogen sulfide efficiently and continuously under mild conditions. The gas distribution unit, the reaction unit and the tail gas absorption unit are connected by pipelines, valves and automatic control instruments to control the temperature of the reaction process. By designing a new reaction tube, the continuous reaction of hydrogen sulfide is achieved, which will have important research significance and practical value for realizing the resource utilization of hydrogen sulfide.

[0025] The present invention also provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which comprises the following steps:

[0026] After heating and cooling the hydrogen sulfide mixed gas, it is subjected to a continuous multi-stage thermal catalytic decomposition reaction, wherein the process gas generated by each stage of the thermal catalytic decomposition reaction is subjected to the next stage of thermal catalytic decomposition reaction after condensing sulfur, thereby obtaining hydrogen-containing tail gas and sulfur products;

[0027] The residual hydrogen sulfide in the hydrogen-containing tail gas is absorbed by an alkaline solution to obtain a hydrogen product.

[0028] In the method of the present invention, the hydrogen sulfide mixed gas is reacted in a high-temperature reaction tube, and the generated high-temperature sulfur vapor is rapidly cooled and solidified to form insoluble sulfur. The mixed gas is catalytically reacted in the high-temperature reaction tube again, and the generated high-temperature sulfur vapor is condensed again to form insoluble sulfur. The reaction cycle is continuous, and the hydrogen is absorbed and purified by amine liquid and then recovered.

[0029] The above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide is preferably implemented by using the above device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, and the method comprises the following steps:

[0030] The hydrogen sulfide mixed gas is heated in the first reaction tube and cooled in the first sulfur trap, and then enters other alternately connected reaction tubes and sulfur traps to alternately perform multi-stage thermal catalytic decomposition reactions and multi-stage sulfur condensation, and hydrogen-containing tail gas is obtained at the outlet of the last reaction tube, and each sulfur trap obtains a sulfur product;

[0031] The hydrogen-containing tail gas is allowed to enter a tail gas absorption unit to absorb residual hydrogen sulfide and dry to obtain a hydrogen product.

[0032] In the method of the present invention, when no catalyst is placed in the first reaction tube, hydrogen sulfide gas will also undergo partial decomposition reaction during the heating process to produce sulfur products. Therefore, the present invention connects a sulfur collector after the first reaction tube to separate the sulfur products.

[0033] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the thermal catalytic decomposition reaction is carried out at level 2-5.

[0034] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the scrubber of the tail gas absorption unit is filled with an alkaline solution, and the hydrogen-containing tail gas is freed of hydrogen sulfide in the scrubber.

[0035] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the alkaline solution comprises alkali solution and amine solution. The alkali solution comprises sodium hydroxide and / or potassium hydroxide, and the amine solution comprises ethylenediamine and / or diethanolamine.

[0036] In the above-mentioned device for continuously reacting hydrogen sulfide to produce hydrogen and sulfur, preferably, the drying tube of the tail gas absorption unit is filled with at least one of color-changing silica gel, activated carbon, and molecular sieve. In the present invention, there are 2-3 gas washing bottles with a volume of 100-200ml, filled with 50-100ml of 20% alkali solution and 50-100ml of amine solution.

[0037] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the temperature of the thermal catalytic decomposition reaction is 500-1600°C, more preferably 800-1300°C.

[0038] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the total reaction residence time of each stage of thermal catalytic decomposition reaction is 6-30s.

[0039] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the thermal catalytic decomposition reaction is carried out under the catalysis of a catalyst, the catalyst is selected from a metal or its sulfide or oxide, and the metal is selected from Na, Li, K, Mg, Al, Fe, V, Cr, Mo, W. The catalyst is more preferably MoS.

[0040] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the temperature of multi-stage condensation of sulfur is 5-30°C.

[0041] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the temperature of the hydrogen absorption bottle is 25-90°C.

[0042] In the above method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, preferably, the hydrogen sulfide mixed gas comprises hydrogen sulfide and a carrier gas, wherein the hydrogen sulfide in the hydrogen sulfide mixed gas may have any concentration.

[0043] The present invention has the following advantages and beneficial effects:

[0044] The cyclic temperature-variable device and method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide provided by the present invention connects the gas distribution unit, the reaction unit, and the tail gas absorption unit through pipelines, valves, and automatic control instruments, controls the temperature of the reaction process, and realizes continuous reaction of hydrogen sulfide by designing a new reaction tube. The reaction method can break the reaction equilibrium, promote the forward movement of the hydrogen sulfide cracking reaction, and improve the primary yield under milder conditions; at the same time, the reaction device realizes the separation of hydrogen sulfide cracking products, and at the same time realizes the acquisition of sulfur and high-purity hydrogen. In some specific embodiments, the method of the present invention successfully achieves a hydrogen sulfide conversion rate of more than 70% under mild conditions, and a stable hydrogen yield of 70%. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a schematic diagram of the device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide in Example 1.

[0046] Description of Figure Numbers:

[0047] 1-1, first reaction tube, 1-2, second reaction tube, 1-3, third reaction tube, 2-1, first sulfur trap, 2-2, second sulfur trap, 2-3, third sulfur trap, 3, reaction heater, 4, mixed gas tank, 5-1, hydrogen sulfide storage tank, 5-2, nitrogen storage tank, 6-1, first gas flow meter, 6-2, second gas flow meter, 7, gas washing bottle, 8, drying tube, 9, hydrogen absorption bottle. DETAILED DESCRIPTION

[0048] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0049] Example 1

[0050] This embodiment provides a device for continuously reacting hydrogen sulfide to produce hydrogen and sulfur, such as Figure 1 As shown, it includes a gas distribution unit, a reaction unit, and a tail gas absorption unit;

[0051] The reaction unit comprises a first reaction tube 1-1, a first sulfur trap 2-1, a second reaction tube 1-2, a second sulfur trap 2-2, a third reaction tube 1-3, a third sulfur trap 2-3, and a reaction heater 3 for heating the reaction tubes, which are alternately connected in sequence, wherein the first reaction tube 1-1 is an L-shaped reaction tube, and the second reaction tube 1-2 and the third reaction tube 1-3 are both inverted U-shaped reaction tubes and are filled with catalysts; each sulfur trap is provided with a partition;

[0052] The gas distribution unit includes a mixed gas tank body 4 and a hydrogen sulfide storage tank 5-1 and a nitrogen storage tank 5-2 connected thereto, and a first gas flow meter 6-1 and a second gas flow meter 6-2 are respectively provided on the outlet pipelines of the hydrogen sulfide storage tank 5-1 and the nitrogen storage tank 5-2, and the outlet of the mixed gas tank body 4 is connected to the inlet of the first reaction tube 1-1;

[0053] The tail gas absorption unit comprises a scrubbing bottle 7, a drying pipe 8 and a hydrogen absorption bottle 9 which are connected in sequence, and the inlet of the scrubbing bottle 7 is connected to the outlet of the third sulfur trap 2-3.

[0054] Example 2

[0055] This embodiment provides a device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which includes a gas distribution unit, a reaction unit, and a tail gas absorption unit;

[0056] The reaction unit comprises 6 reaction tubes and 6 sulfur collectors connected alternately, and a reaction heater for heating the reaction tubes, wherein the first reaction tube is an L-shaped reaction tube, which is 15 cm wide, 30 cm long, with an inner diameter of 0.5 cm and an outer diameter of 1 cm; the other 5 reaction tubes are inverted U-shaped reaction tubes and are filled with catalysts, which are 15 cm wide, 30 cm long, with an inner diameter of 0.5 cm and an outer diameter of 1 cm; a partition is provided in the sulfur collector, and the pipeline between the sulfur collector and the reaction tube is insulated by a heating belt, which is a high-temperature glass fiber heating belt with a width of 3 cm;

[0057] The tail gas absorption unit comprises two washing bottles, a drying tube and a hydrogen absorption bottle which are connected in sequence, and the inlet of the washing bottle is connected to the outlet of the third sulfur trap; 100 ml of ethylenediamine solution is respectively loaded into the washing bottles, the volume of the drying tube is 200 ml, 1 / 3 of color-changing silica gel, 1 / 3 of activated carbon, and 1 / 3 of molecular sieve are put in, and the outlet of the drying tube is connected to the hydrogen absorption bottle;

[0058] The gas distribution unit includes a 100mL mixed gas tank body and a hydrogen sulfide storage tank and a nitrogen storage tank connected thereto. Gas flow meters are respectively provided on the outlet pipelines of the hydrogen sulfide storage tank and the nitrogen storage tank. The outlet of the mixed gas tank body is connected to the inlet of the L-shaped reaction tube.

[0059] A gas sampling port is also provided after the gas outlet of the last sulfur collector to detect the concentration of hydrogen sulfide and hydrogen in the tail gas and determine the conversion rate. The gas sampling port is connected to the gas outlet of the sulfur collector and the inlet of the gas washing bottle through a three-way ferrule.

[0060] Example 3

[0061] The present embodiment provides a device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as the embodiment 2, except that the number of inverted U-shaped reaction tubes in the present embodiment is 3, and the corresponding number of sulfur collectors is 4; and the specifications of the reaction tubes are different. The specifications of the L-shaped reaction tube are: 23 cm wide, 55 cm long, 1 cm inner diameter of the reaction tube, and 2 cm outer diameter. The specifications of the inverted U-shaped reaction tube are: 23 cm wide, 55 cm long, 1 cm inner diameter of the reaction tube, and 2 cm outer diameter.

[0062] Example 4

[0063] The present embodiment provides a device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as the embodiment 2, except that the number of inverted U-shaped reaction tubes in the present embodiment is 2, and the corresponding number of sulfur collectors is 3; and the specifications of the reaction tubes are different. The specifications of the L-shaped reaction tube are: 30 cm wide, 80 cm long, 2 cm inner diameter of the reaction tube, and 3 cm outer diameter, and the specifications of the inverted U-shaped reaction tube are: 30 cm wide, 80 cm long, 2 cm inner diameter of the reaction tube, and 3 cm outer diameter.

[0064] Example 5

[0065] This embodiment provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is implemented using the device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide of embodiment 2. The method comprises the following steps:

[0066] The hydrogen sulfide and nitrogen are mixed by using a gas distribution unit to obtain a 10% concentration of hydrogen sulfide mixed gas (the volume concentration of hydrogen sulfide is 10%), and the flow rate of the mixed gas is controlled to be 100 mL / min by using a gas flow meter;

[0067] The hydrogen sulfide mixed gas is heated in the L-shaped reaction tube and cooled in the first sulfur trap, and then enters other alternately connected U-shaped reaction tubes and sulfur traps to alternately perform multi-stage thermal catalytic decomposition reactions and multi-stage sulfur condensation, and the outlet of the last reaction tube obtains hydrogen-containing tail gas, and each sulfur trap obtains a sulfur product; wherein the temperature of the reaction heater (i.e., the temperature of the L-shaped reaction tube and the U-shaped reaction tube) is 800°C, and the U-shaped reaction tube is filled with a catalyst MoS; the temperature of the pipeline heating zone is set to 250°C, and the temperature of the condensed sulfur is 25°C;

[0068] The hydrogen-containing tail gas is sequentially entered into the washing bottle and drying tube of the tail gas absorption unit, residual hydrogen sulfide is removed by ethylenediamine in the washing bottle, dried and purified in the drying tube, and finally enters into the hydrogen absorption bottle.

[0069] In this embodiment, during the reaction process, the hydrogen sulfide mixed gas is reacted in a high-temperature reactor, and the generated high-temperature sulfur vapor is rapidly cooled and solidified to form insoluble sulfur. The mixed gas is catalytically reacted in the high-temperature reactor again, and the generated high-temperature sulfur vapor is rapidly cooled and solidified again to form insoluble sulfur, forming a continuous reaction cycle.

[0070] Example 6

[0071] This embodiment provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as that of Embodiment 5 and is also implemented using the apparatus for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide of Embodiment 2, except that the temperature of the reaction heater is 1300°C.

[0072] Example 7

[0073] This embodiment provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as that of Embodiment 5 and is also implemented using the apparatus for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide of Embodiment 2, except that the concentration of hydrogen sulfide in the hydrogen sulfide mixed gas is 20% and the temperature of the reaction heater is 800°C.

[0074] Example 8

[0075] This embodiment provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as that of Embodiment 5 and is also implemented using the apparatus for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide of Embodiment 2, except that the concentration of hydrogen sulfide in the hydrogen sulfide mixed gas is 50% and the temperature of the reaction heater is 800°C.

[0076] In the above examples 5-8, the tail gas was sampled at the sampling port of the last sulfur collector for gas chromatography analysis to calculate the reaction conversion rate and hydrogen yield; the samples were taken three times within 60 minutes, and the calculation results showed that the conversion rate exceeded 97%. In addition, a sampling port was connected after the gas washing bottle to test the purity of hydrogen. The specific measurement results are shown in Table 1.

[0077] Table 1 Hydrogen sulfide continuous reaction conversion rate and hydrogen purity under different reaction conditions

[0078]

[0079]

[0080] The device and method of the present invention promote the equilibrium reaction to move toward the product direction by alternately performing multi-stage thermal catalytic decomposition reaction and multi-stage desulfurization condensation. At a higher reaction temperature of 1300°C, the cumulative conversion rate of the multi-stage reaction can reach 97-99%; and at a lower reaction temperature, the conversion rate of hydrogen sulfide can also be improved. At the same time, the purity of the obtained hydrogen product is also relatively high.

[0081] Comparative Example 1

[0082] This comparative example provides a device for producing hydrogen and sulfur by reacting hydrogen sulfide, which is the same as Example 2, except that the number of reaction tubes and sulfur collectors in this comparative example is 1, and the reaction tube is an inverted U-shaped reaction tube.

[0083] Comparative Example 2

[0084] This comparative example provides a method for producing hydrogen and sulfur by reacting hydrogen sulfide, which is the same as Example 5, except that this comparative example is implemented using the apparatus of Comparative Example 1.

[0085] Comparative Example 3

[0086] This comparative example provides a device for producing hydrogen and sulfur by reacting hydrogen sulfide, which is the same as Example 2, except that this comparative example has no sulfur trap, and the reaction unit has only two inverted U-shaped reaction tubes connected by pipelines.

[0087] Comparative Example 4

[0088] This comparative example provides a method for producing hydrogen and sulfur by reacting hydrogen sulfide, which is the same as Example 5, except that this comparative example is implemented using the apparatus of Comparative Example 3.

[0089] Comparative Example 5

[0090] This comparative example provides a method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, which is the same as Example 5 and is also implemented using the device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide of Example 2, except that the temperature of the reaction heater is 300°C.

[0091] The hydrogen sulfide conversion rate and hydrogen product purity of the methods of Comparative Examples 2, 4 and 5 were tested, and the results are shown in Table 2.

[0092] Table 2 Hydrogen sulfide continuous reaction conversion rate and hydrogen purity under different reaction conditions

[0093]

[0094] According to Table 2, only one-stage thermal catalytic decomposition reaction occurred in Comparative Example 2, and the hydrogen sulfide conversion rate was very low; Comparative Example 4 did not cool and desulfurize the reaction products at each stage, and its hydrogen sulfide conversion rate was also very low; Comparative Example 5 had a low reaction temperature, an insufficient reaction, and a low hydrogen sulfide conversion rate.

Claims

1. A device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, comprising a gas distribution unit, a reaction unit, and a tail gas absorption unit; in, The reaction unit comprises at least two reaction tubes and at least two sulfur traps which are alternately connected in sequence, and a reaction heater for heating the reaction tubes; The outlet of the gas distribution unit is connected to the inlet of the first reaction tube, and the outlet of the last sulfur trap is connected to the inlet of the tail gas absorption unit.

2. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The tail gas absorption unit comprises a scrubbing bottle, a drying tube and a hydrogen absorption bottle which are connected in sequence; the inlet of the scrubbing bottle is connected to the outlet of the last sulfur trap.

3. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The gas distribution unit comprises a hydrogen sulfide storage tank and a mixed gas tank body which are connected through a pipeline, and a gas flow meter is arranged on the pipeline between the two.

4. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The reaction unit comprises 3-6 reaction tubes.

5. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The reaction tube is filled with a catalyst.

6. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: A catalyst is installed in each reaction tube starting from the second reaction tube.

7. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The first reaction tube is an L-shaped reaction tube or an inverted U-shaped reaction tube; and each reaction tube from the second reaction tube onwards is an inverted U-shaped reaction tube.

8. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The reaction tube is arranged inside the reaction heater.

9. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: A partition is arranged inside the sulfur capture.

10. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The sulfur capture is provided with an air inlet and an air outlet, wherein the air inlet is connected to the outlet of the preceding reaction tube, and the air outlet is connected to the succeeding reaction tube.

11. The device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 1, wherein: The device also includes pipelines, valves and automatic control instruments connecting the units.

12. A method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide, comprising the following steps: The hydrogen sulfide mixed gas is heated and cooled, and then subjected to a continuous multi-stage thermal catalytic decomposition reaction, wherein: The process gas generated by each stage of thermal catalytic decomposition reaction is subjected to the next stage of thermal catalytic decomposition reaction after condensing sulfur, thereby obtaining hydrogen-containing tail gas and sulfur products; The residual hydrogen sulfide in the hydrogen-containing tail gas is absorbed by an alkaline solution to obtain a hydrogen product.

13. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 12, wherein: The method is implemented by using the device for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to any one of claims 1 to 11, and the method comprises the following steps: The hydrogen sulfide mixed gas is heated in the first reaction tube and cooled in the first sulfur trap, and then enters other alternately connected reaction tubes and sulfur traps to alternately perform multi-stage thermal catalytic decomposition reactions and multi-stage sulfur condensation, and hydrogen-containing tail gas is obtained at the outlet of the last reaction tube, and each sulfur trap obtains a sulfur product; The hydrogen-containing tail gas is allowed to enter a tail gas absorption unit to absorb residual hydrogen sulfide and dry to obtain a hydrogen product.

14. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 13, wherein: The washing bottle of the tail gas absorption unit is filled with an alkaline solution, and the hydrogen-containing tail gas is desulfurized in the washing bottle.

15. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 13, wherein: The drying tube of the tail gas absorption unit is filled with at least one of color-changing silica gel, activated carbon and molecular sieve.

16. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 12 or 13, wherein: The temperature of the thermal catalytic decomposition reaction is 500-1600°C, preferably 800-1300°C.

17. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 12 or 13, wherein: The reaction residence time of each stage of thermal catalytic decomposition reaction is 6-30s.

18. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 12 or 13, wherein: The thermal catalytic decomposition reaction is carried out under the catalysis of a catalyst, wherein the catalyst is selected from a metal or its sulfide or its oxide, and the metal is selected from Na, Li, K, Mg, Al, Fe, V, Cr, Mo, and W.

19. The method for producing hydrogen and sulfur by continuous reaction of hydrogen sulfide according to claim 12 or 13, wherein: The temperature of multi-stage condensed sulfur is 5-30℃.

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