Hydrogen sulfide to methane reforming apparatus and systems and methods employing the same

Abstract

The application discloses a hydrogen sulfide and methane reforming device, which at least comprises: a reforming unit arranged at the bottom of the device and having a reforming settling zone and a reforming reaction zone; in the reforming reaction zone in the form of a fluidized bed, H2S and CH4 are used as fluidized gas, and H2S and CH4 are converted into H2 and CS2 through a reforming reaction under the action of a sulfidized catalyst; a regeneration unit having a regeneration zone and a regeneration settling zone arranged at the top of the device; the regeneration zone is an internal space of a riser pipe extending upward from the bottom of the device to the regeneration settling zone, and is used for driving the deactivated catalyst from the reforming reaction zone to move upward and be oxidatively regenerated by taking air as fluidized gas; and a sulfidation unit having an upper gas collecting zone for guiding H2S gas to be bended, a sulfidation zone and a lower gas collecting zone; the sulfidation zone is a radial reaction zone, in the sulfidation zone, the oxidized catalyst from the regeneration settling zone moving axially downward is contacted with the radial H2S gas, and the oxidized catalyst is pre-sulfidized by taking H2S as sulfidation gas, so that the sulfidized catalyst is generated and is conveyed downward to the reforming settling zone.

Description

Technical Field

[0001] This invention relates to the field of hydrogen sulfide utilization technology, and in particular to a hydrogen sulfide and methane reforming apparatus, as well as a system and method for using the apparatus. Background Technology

[0002] Hydrogen sulfide (H2S) is an important sulfur resource, mainly produced in sulfur-containing natural gas and petroleum refining processes, and also generated in coking, coal gasification, and petrochemical processes. H2S not only causes corrosion of metals and other materials, but also easily leads to catalyst poisoning and deactivation in chemical production; furthermore, H2S harms human health and causes environmental pollution. Therefore, the proper treatment and utilization of acidic gases containing H2S is both a necessity for efficient resource utilization and a requirement of increasingly stringent environmental protection standards.

[0003] Currently, H2S treatment mainly employs the Claus sulfur recovery process, which is also the most widely used sulfur recovery technology. However, in the Claus process, only sulfur (S) is recovered as a sulfur product, while hydrogen (H) is converted into H2O in the thermal reaction section, resulting in a significant loss of hydrogen resources. Furthermore, sulfur itself has low added value, and the market supply of sulfur exceeds demand. Therefore, the Claus sulfur recovery process is primarily positioned as an environmentally friendly technology.

[0004] Existing technologies include extensive research on the direct decomposition of H2S, a relatively ideal technological route for the resource utilization of H2S. This route can render H2S harmless while producing hydrogen and elemental sulfur, enabling the recycling of hydrogen resources in petroleum processing and reducing the large amounts of carbon dioxide emissions from traditional hydrocarbon reforming for hydrogen production. However, this technology is currently in the experimental exploration stage, and problems such as low theoretical conversion rates and the tendency of generated sulfur to clog pipelines have not yet been effectively resolved.

[0005] To achieve efficient utilization of H2S, the new hydrogen sulfide methane reforming technology uses H2S as raw material. Under the action of a proprietary catalyst, H2S undergoes a reforming reaction with CH4 to produce H2 and CS2. The application prospects of hydrogen sulfide methane reforming technology include: (1) it can be directly used for the treatment of sulfur-containing natural gas, achieving efficient desulfurization while also obtaining hydrogen-blended natural gas and by-product CS2; (2) it can also be combined with refinery sulfur recovery to form a joint unit, generating hydrogen from a large amount of acid gas and co-producing CS2, thus turning waste into treasure. Compared with the raw materials, the products (H2 and CS2) have higher added value.

[0006] Chinese patent application CN113428861A discloses a process for producing hydrogen from methane and hydrogen sulfide through reforming. The method includes the following steps: (1) catalytically reacting a feed gas containing CH4 and H2S at 600-900℃ to obtain reaction gas I; (2) separating reaction gas I to obtain sulfur and reaction gas II; (3) flash distilling reaction gas II to obtain crude CS2 liquid and reaction gas III; (4) rectifying the crude CS2 liquid to obtain liquid CS2 with a mass fraction of not less than 99.5%; contacting reaction gas III with an absorbent to obtain hydrogen-rich gas and a rich absorbent; and (5) separating the hydrogen-rich gas to obtain hydrogen with a volume fraction of more than 99.99% and a desorbed gas. In this scheme, the catalytic reactor is a tubular reactor, with the feed gas flowing through the tube side and the fuel gas flowing through the shell side. The catalytic reforming reaction in the tube side is a strongly endothermic reaction, and the heat for the reaction is provided by burning the fuel gas in the shell side.

[0007] The catalysts involved in this type of process are highly susceptible to carbon buildup when reacting with methane and hydrogen sulfide at high temperatures, leading to catalyst deactivation. When the deactivated catalyst is regenerated, the process faces intermittent shutdowns, which is unacceptable for industrial plants. This existing technology does not offer a solution to ensure the continuous and stable operation of the entire process.

[0008] Therefore, there is an urgent need for a hydrogen sulfide and methane reforming unit, as well as a system and method for using such a unit, so that reforming, regeneration and sulfidation can be continuously cycled and completed in the same unit during the reforming reaction, which can effectively ensure the continuous and stable operation of the reforming process.

[0009] The information disclosed in this background section is intended only to enhance the understanding of the overall background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art known to those skilled in the art. Summary of the Invention

[0010] The purpose of this invention is to provide a hydrogen sulfide and methane reforming device, as well as a system and method for using the device. By setting up a reforming unit, a regeneration unit, and a sulfidation unit in the same reforming device to form a process cycle, the problem of the reaction not being able to run continuously due to carbon deposition and deactivation of the reforming catalyst can be effectively solved, thereby enabling the catalyst to achieve long-term operation under high activity.

[0011] To achieve the above objectives, according to a first aspect of the present invention, a hydrogen sulfide and methane reforming apparatus is provided, comprising at least: a reforming unit disposed at the bottom of the apparatus and having a reforming settling zone and a reforming reaction zone; wherein, in the reforming reaction zone in the form of a fluidized bed, H2S and CH4 are used as fluidizing gases, and under the action of a sulfide-state catalyst, H2S and CH4 are reformed to generate H2 and CS2; and a regeneration unit having a regeneration zone and a regeneration settling zone located at the top of the apparatus; the regeneration zone extends from the bottom of the apparatus upwards to the regeneration settling zone. The internal space of the riser in the zone is used to drive the deactivated catalyst from the reforming reaction zone upward and perform oxidation regeneration using air as the fluidizing gas; the sulfidation unit has an upper gas collecting zone, a sulfidation zone, and a lower gas collecting zone for guiding H2S gas through a deflection process; the sulfidation zone is a radial reaction zone in which the oxidized catalyst moving axially downward from the regeneration settling zone comes into contact with the radially moving H2S gas, and is used to pre-sulfidate the oxidized catalyst using H2S as the sulfidation gas to generate a sulfidated catalyst, which is then transported downward to the reforming settling zone.

[0012] Furthermore, in the above technical solution, the vulcanization zone is a radial reactor structure with multiple uniformly spaced hollow walls. The radial reactor has an inner wall and an outer wall, which are used to allow the H2S gas that is deflected here to pass through the inner and outer walls to form H2S gas running radially within the vulcanization zone.

[0013] Furthermore, in the above technical solution, the upper gas collecting zone, the sulfidation zone, and the lower gas collecting zone can be constructed as a baffle channel for H2S gas.

[0014] Furthermore, in the above technical solution, the baffle channel can be constructed by an upper baffle plate, a lower baffle plate, and an arc-shaped baffle plate; the upper baffle plate can be located at the bottom of the upper gas collection zone and on the side of the device wall, the lower baffle plate can be located at the top of the lower gas collection zone and on the side of the device axis, and the arc-shaped baffle plate can be located circumferentially between adjacent radial reactors.

[0015] Furthermore, in the above technical solution, a gas outlet is provided at the bottom of the lower gas collection zone of the sulfidation unit, and the gas outlet pipeline extends downward to the fluidized bed of the reforming reaction zone, and a gas outlet regulating valve may be provided on the pipeline; a catalyst feed port is provided at the bottom of the sulfidation zone, and the feed port outlet pipeline extends downward to the reforming settling zone, and a feed regulating valve may be provided on the pipeline.

[0016] Furthermore, in the above technical solution, a first cyclone separator is provided at the top of the reforming reaction zone to separate the high-temperature reforming reaction gaseous products from the catalyst particles, and the separated catalyst particles are returned to the fluidized bed of the reforming reaction zone.

[0017] Furthermore, in the above technical solution, the high-temperature reforming reaction gas phase products can exchange heat with the H2S gas prepared for pre-sulfurization that is about to enter the upper gas collecting zone through the first heat exchanger.

[0018] Furthermore, in the above technical solution, the catalyst outlet at the bottom of the reforming reaction zone can be connected to the bottom of the riser through two sections of preheating inclined tubes; a second heat exchanger can be provided between the two sections of preheating inclined tubes to preheat the CH4 feed gas that is about to enter the reforming reaction zone with the high-temperature deactivated catalyst.

[0019] Furthermore, in the above technical solution, the preheated CH4 feed gas can be mixed with the preheated H2S feed gas through a gas mixer and then introduced into a gas distributor set at the bottom of the reforming reaction zone.

[0020] Furthermore, in the above technical solution, a second cyclone separator is provided at the top of the regeneration settling zone to receive the oxidized catalyst from the regeneration zone and perform gas-solid separation; the separated coke flue gas is discharged from the device and can be preheated by the H2S feed gas through a third heat exchanger.

[0021] Furthermore, in the above technical solution, a bed with a narrow diameter can be provided at the bottom of the regeneration settling zone to transport the oxidized catalyst to the sulfidation zone of the sulfidation unit. At the same time, the bottom of the bed can also leave enough gas collection space for the upper gas collection chamber of the sulfidation unit.

[0022] According to a second aspect of the present invention, the present invention provides a hydrogen sulfide and methane reforming system, employing the aforementioned apparatus, and further comprising: a CS2 separation unit, which receives the reaction products from the hydrogen sulfide and methane reforming unit, and obtains the CS2 product after flash evaporation and low-temperature distillation; an H2S separation unit, which receives a gaseous stream containing H2S, CH4, and H2 from the CS2 separation unit, and performs high-precision separation of H2S by low-temperature methanol washing, wherein the separated H2S can be recycled as feed gas for the hydrogen sulfide and methane reforming unit; and an H2 purification unit, which receives a gaseous stream containing CH4 and H2 from the H2S separation unit, and produces high-purity hydrogen by pressure swing adsorption; wherein the separated CH4 can be recycled as feed gas for the hydrogen sulfide and methane reforming unit.

[0023] Furthermore, in the above technical solution, the CS2 separation device preferably includes a primary flash tank, a secondary flash tank, and a distillation column; the H2S separation device preferably includes an H2S absorption column, a flash tank, and a methanol regeneration column; the H2 purification device can be a PSA unit.

[0024] According to a third aspect of the present invention, the present invention provides a method for reforming hydrogen sulfide and methane, employing the aforementioned system, comprising at least the following steps: A. In a reforming reaction zone in the form of a fluidized bed, using H2S and CH4 as fluidizing gases, H2S and CH4 are reformed to generate H2 and CS2 under the action of a sulfidated catalyst; B. Using air as the fluidizing gas, the catalyst deactivated from the reforming reaction zone is driven upward and oxidized and regenerated through a regeneration zone constructed by a riser; C. The oxidized and regenerated catalyst is conveyed downward to a sulfidation zone and contacted with radially moving H2S gas in the sulfidation zone, using H2S as the sulfidation gas to pre-sulfidate the oxidized catalyst, generating a sulfidated catalyst, which is then conveyed downward to the reforming settling zone; returning to step A to form a cycle.

[0025] Furthermore, in the above technical solution, the operating conditions for the reforming reaction are as follows: the reaction temperature is preferably 800℃, and the reaction pressure is preferably atmospheric pressure to 0.8 MPa. The catalyst used in the reforming reaction is preferably a supported catalyst, and the active component can be one or more of molybdenum oxide, iron oxide, cobalt oxide, etc.; the support can be one or more of alumina, silicon oxide, titanium oxide, silica-alumina molecular sieve, etc.

[0026] Furthermore, in the above technical solution, the method may also include the following steps: D. Performing two-stage flash evaporation and low-temperature distillation on the reaction product after the reforming reaction in step A to obtain CS2 product; E. Performing high-precision separation of H2S by low-temperature methanol washing on the gaseous stream containing H2S, CH4, and H2 separated in step D, and recycling the separated H2S as the feed gas for step A; F. Producing high-purity hydrogen by pressure swing adsorption on the gaseous stream containing CH4 and H2 separated in step E; recycling the separated CH4 as the feed gas for step A.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1) The hydrogen sulfide and methane reforming unit of this invention uses H2S as raw material. Under the action of a proprietary catalyst, H2S and CH4 undergo a reforming reaction (2H2S + CH4 → 4H2 + CS2) to produce H2 and CS2. The system and method of this invention employ a process route that utilizes hydrogen sulfide while also producing hydrogen. Compared with the Claus sulfur recovery process, this technology has extremely high atom utilization, achieving efficient utilization of H, C, and S elements. H elements recovered from H2S and CH4 can be used to produce high-purity hydrogen, while the recovered C and S elements can be converted into CS2. Compared with direct decomposition of hydrogen sulfide, the advantage of this technology lies in the fact that the addition of methane significantly improves the conversion rate of hydrogen sulfide, resulting in a high hydrogen production rate; and compared with CH4 steam reforming for hydrogen production, there are no CO or CO2 emissions.

[0029] 2) The reforming device of the present invention adopts a fluidized bed reforming reaction zone, which can discharge the deactivated catalyst with carbon deposits online and continuously regenerate it in the upward riser. Then, the catalyst is pre-sulfurized in the continuously flowing radial reaction zone. After the catalyst is restored to its active state, it is recycled back to the reforming unit for continuous use. Through the reforming-regeneration-sulfurization process, the regeneration and stable circulation of the catalyst are realized, ensuring the stable operation of the process.

[0030] 3) Since the reforming reaction is an endothermic process and the regeneration reaction is an exothermic process, this invention couples the two processes and designs the reforming, regeneration, and sulfidation reactions in an axial partition according to their functions; it adopts a mode of embedding the regeneration unit (i.e., the upward riser) within the reforming unit and the sulfidation unit, using the heat released by the regeneration reaction to provide heat for the reforming and sulfidation reactions, reducing the reaction's need for external heating; at the same time, it also recovers heat from the material flow before and after the reaction, thereby achieving optimized utilization of heat internally;

[0031] 4) The reforming device of the present invention, by using the internal space of the riser as the regeneration zone, can not only integrate the reforming, regeneration and sulfidation processes in the same device, but also realize the continuous and stable operation of the device. It can effectively solve the problem that the reaction cannot be continuously operated due to the deactivation of the catalyst due to carbon deposition during the reforming of hydrogen sulfide and methane, and enable the catalyst to achieve long-term operation under high activity.

[0032] 5) The reforming apparatus of the present invention guides the H2S gas to be deflected in the sulfidation unit and forms a radial flow (i.e., a radial reaction zone) in the sulfidation zone, which can achieve full contact between the H2S gas and the oxidized catalyst, convert the oxidized catalyst into the sulfided state, so that it has higher reforming reaction activity, better pre-sulfidation effect, and can create better conditions for the reforming reaction.

[0033] 6) The reforming apparatus of the present invention can make full use of the heat of the gas phase reaction products to preheat the feed gas by setting the first heat exchanger and the third heat exchanger; and can make full use of the deactivated high-temperature solid catalyst to preheat the feed gas by setting the second heat exchanger, thus achieving full utilization of heat.

[0034] 7) The reforming device of the present invention uses a “narrowing” bed in the lower part of the regeneration settling zone. That is, the upper part of the regeneration settling zone is cylindrical and the lower part is conical with a concave center. This structure facilitates the uniform dispersion of catalyst solid particles along the circumferential direction. The catalyst flows downward into the sulfidation zone (i.e., the radial reaction zone) through symmetrically distributed catalyst feed pipes. While supplying oxidized catalyst to the sulfidation zone of the sulfidation unit, the narrowing of the bottom of the bed can also leave enough gas collection space for the upper gas collection chamber of the sulfidation unit, creating more favorable conditions for the “radial inflow” into the sulfidation zone.

[0035] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it according to the contents of the specification, and to make the above and other objects, technical features and advantages of the present invention easier to understand, one or more preferred embodiments are listed below and described in detail with reference to the accompanying drawings. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the hydrogen sulfide and methane reforming apparatus of the present invention.

[0037] Figure 2 yes Figure 1 A schematic diagram of the sulfurization unit in the reforming plant (the arrows in the diagram indicate the direction of H2S gas flow).

[0038] Figure 3 yes Figure 1 A top view of the cross-section at point AA.

[0039] Figure 4 yes Figure 1 A top view of the cross-section at point BB.

[0040] Figure 5 yes Figure 1 A top-view cross-section of the CC section (the dashed arrows in the figure indicate the direction of gas flow in the sulfidation zone).

[0041] Figure 6 yes Figure 1 A top view of the cross-section at point DD.

[0042] Figure 7 This is a schematic diagram of the connection of the hydrogen sulfide and methane reforming system of the present invention.

[0043] Explanation of key figure labels:

[0044] R1 - Hydrogen sulfide and methane reforming unit, D1 - Primary flash tank, D2 - Secondary flash tank, D3 - Distillation column, S1 - H2S absorption column, S2 - Flash tank, S3 - Methanol regeneration column, H1 - PSA unit.

[0045] 1-Reforming unit, 1A-Reforming settling zone, 1B-Reforming reaction zone, 11-Gas distributor, 110-Gas mixer, 12-Sulfur gas outlet pipeline, 13-First cyclone separator, 14-Reforming inclined tube, 141-Reforming agent regulating valve.

[0046] 2-Regeneration unit, 2A-Regeneration zone (inside the riser pipe), 2B-Regeneration settling zone, 21-Second cyclone separator, 22-Bed diameter reduction section, 23-Catalyst inlet pipe of sulfidation zone;

[0047] 3-Sulfurization unit, 3A-Upper gas collection zone, 3B-Sulfurization zone, 3C-Lower gas collection zone, 30-Sulfurization gas inlet, 301-Radial reactor inner wall, 302-Radial reactor outer wall, 303-Sulfurization zone catalyst discharge port, 304-Discharge port regulating valve, 305-Sulfurization gas outlet, 306-Gas outlet regulating valve, 31-Upper isolation plate, 32-Lower isolation plate, 33-Arc-shaped isolation plate;

[0048] E1 - First heat exchanger, E2 - Second heat exchanger, E3 - Third heat exchanger. Detailed Implementation

[0049] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but it should be understood that the scope of protection of the present invention is not limited to the specific embodiments.

[0050] Unless otherwise expressly stated, throughout the specification and claims, the term "comprising" or its variations such as "including" or "comprises" shall be understood to include the stated elements or components without excluding other elements or other components.

[0051] In this document, for ease of description, spatial relative terms such as “below,” “under,” “down,” “above,” “above,” “upper,” etc., are used to describe the relationship of one element or feature to another element or feature in the accompanying drawings. It should be understood that spatial relative terms are intended to encompass different orientations of an object in use or operation, in addition to those depicted in the figures. For example, if an object in the figure is flipped, an element described as “below” or “under” another element or feature would be oriented “above” that element or feature. Thus, the exemplary term “below” can encompass both the downward and upward orientations. An object may also have other orientations (rotated 90 degrees or other orientations), and the spatial relative terms used herein should be interpreted accordingly.

[0052] In this document, the terms "first," "second," etc., are used to distinguish two different elements or parts, and are not used to define specific positions or relative relationships. In other words, in some embodiments, the terms "first," "second," etc., can also be used interchangeably.

[0053] The hydrogen sulfide and methane reforming unit of this invention uses H2S as raw material. Under the action of a proprietary catalyst, H2S and CH4 undergo a reforming reaction (2H2S + CH4 → 4H2 + CS2) to produce H2 and CS2. The system and method of this invention employ a process route that utilizes hydrogen sulfide while also producing hydrogen. Compared with the Claus sulfur recovery process, this technology has extremely high atom utilization, achieving efficient utilization of H, C, and S elements. H element recovered from H2S and CH4 can be used to produce high-purity hydrogen, while recovered C and S elements can be converted into CS2. Compared with direct decomposition of hydrogen sulfide, the advantage of this technology lies in the fact that the addition of methane significantly improves the conversion rate of hydrogen sulfide, resulting in a high hydrogen production rate. Compared with CH4 steam reforming for hydrogen production, there are no CO or CO2 emissions.

[0054] like Figure 1 As shown, the present invention provides a hydrogen sulfide and methane reforming apparatus R1, comprising at least a reforming unit 1, a regeneration unit 2, and a sulfidation unit 3. The reforming unit 1 is located at the bottom of the reforming apparatus and has a reforming settling zone 1A and a reforming reaction zone 1B. In the fluidized bed-type reforming reaction zone 1B, H2S and CH4 are used as fluidizing gases, and under the action of a sulfidated catalyst, H2S and CH4 are reformed to generate H2 and CS2. The regeneration unit 2 has a regeneration zone 2A and a regeneration settling zone 2B located at the top of the reforming apparatus. The regeneration zone 2A is the internal space of a riser pipe extending upward from the bottom of the apparatus to the regeneration settling zone 2B, used to drive the deactivated catalyst from the reforming reaction zone 1B upward for oxidative regeneration using air as the fluidizing gas. The sulfidation unit 3 has an upper gas collecting zone 3A, a sulfidation zone 3B, and a lower gas collecting zone 3C for guiding the flow of H2S gas. The sulfidation zone 3B is a radial reaction zone. Within the sulfidation zone 3B, the axially downward-moving oxidized catalyst from the regeneration settling zone 2B contacts the radially moving H2S gas, which is used to pre-sulfidate the oxidized catalyst using H2S as the sulfidation gas, generating a sulfidated catalyst, which is then conveyed downward to the reforming settling zone 1A. Thus, the hydrogen sulfide and methane reforming unit R1 of the present invention completes one cycle of reforming-regeneration-sulfidation-reforming.

[0055] This invention employs the above-mentioned technical solution, using the internal space of the riser as a regeneration zone. This not only integrates the reforming, regeneration, and sulfidation processes into the same device but also enables continuous and stable operation of the device. It effectively solves the problem of catalyst deactivation due to carbon buildup during the reforming of hydrogen sulfide and methane, which prevents continuous operation of the reaction. This allows the catalyst to operate for a long period under high activity. By guiding the H2S gas to bend in the sulfidation unit and forming a radial flow (i.e., a radial reaction zone) in the sulfidation zone, sufficient contact between the H2S gas and the oxidized catalyst can be achieved, converting the oxidized catalyst into the sulfided state, giving it higher reforming reaction activity and better pre-sulfidation effect, thus creating better conditions for the reforming reaction.

[0056] Further as Figure 1 , 2 As shown, the vulcanization zone 3B of the vulcanization unit 3 is a radial reactor structure with multiple evenly spaced perforated walls. The radial reactor has an inner wall 301 and an outer wall 302 (see reference). Figure 2 This is used to guide the H2S gas flowing here through the inner and outer walls, forming a radially flowing H2S gas within the sulfidation zone 3B. The upper gas collecting zone 3A, the sulfidation zone 3B, and the lower gas collecting zone 3C are collectively constructed as a baffle channel for the H2S gas. Preferably, but not limitingly, the baffle channel can be accessed through the upper isolation plate 31 and the lower isolation plate 32 (see reference). Figure 2 ) and curved isolation plate 33 (reference) Figure 4 , Figure 5 The upper isolation plate 31 is located at the bottom of the upper gas collecting zone 3A and on the side of the device wall; the lower isolation plate 32 is located at the top of the lower gas collecting zone 3C and on the side of the device axis; and the arc-shaped isolation plate 33 is arranged circumferentially between adjacent radial reactors, so that the H2S gas running to this location can only move along the axis of the device. Figure 5 The dashed arrows indicate radial flow. The upper and lower baffles can also be positioned in opposite directions; that is, the upper baffle can be positioned on the axial side of the device, and the lower baffle can be positioned on the wall side of the device, as long as a "baffle channel" can be constructed and the H2S gas can flow radially in the sulfidation zone 3B.

[0057] Further as Figure 1 , 2 As shown, the lower gas collection zone 3C of the sulfidation unit 3 has a gas outlet 305 at its bottom, and the gas outlet pipe 12 extends downward to the fluidized bed of the reforming reaction zone 1B, with a gas outlet regulating valve 306 on the pipe 12. The bottom of the sulfidation zone 3B has a catalyst feed port 303, and the feed port outlet pipe extends downward to the reforming settling zone 1A, with a feed regulating valve 304 on the pipe. Furthermore, the top of the reforming reaction zone 1B has a first cyclone separator 13, used to separate the high-temperature reforming reaction gaseous products from the catalyst particles; the separated catalyst particles are returned to the fluidized bed of the reforming reaction zone 1B. The high-temperature reforming reaction gas phase products exchange heat with the H2S gas for pre-sulfurization that is about to enter the upper gas collection zone 3A through the first heat exchanger E1. That is, the high temperature of the reaction gas is used to preheat the H2S gas entering the sulfurization unit 3, heating the H2S gas to a certain temperature before it enters the upper gas collection zone 3A of the sulfurization unit 3, so as to optimize the use of energy.

[0058] Further as Figure 1As shown, the catalyst outlet at the bottom of the reforming reaction zone 1B is connected to the bottom of the riser 2A via two sections of preheating inclined tubes 14. A second heat exchanger E2 is installed between the two sections of preheating inclined tubes 14, which can be used to preheat the CH4 feed gas that is about to enter the reforming reaction zone 1B with the high-temperature deactivated catalyst. That is, the high-temperature deactivated catalyst is used to preheat the CH4 gas, recover energy, and achieve optimized utilization. A preheating agent regulating valve 141 can also be installed on the preheating inclined tubes 14. Further, the preheated CH4 feed gas is mixed with the preheated H2S feed gas through a gas mixer 110 and then introduced into a gas distributor 11 installed at the bottom of the reforming reaction zone 1B, and then the reforming reaction takes place in the reforming reaction zone 1B in the form of a fluidized bed.

[0059] Further as Figure 1 As shown, a second cyclone separator 21 is installed at the upper part of the regeneration settling zone 2B to receive the oxidized catalyst from the regeneration zone 2A (i.e., the riser) and perform gas-solid separation; the separated coke flue gas is discharged from the exhaust device, and the H2S feed gas is preheated through the third heat exchanger E3. Furthermore, a narrow-diameter bed (i.e., bed narrowing section 22) is installed at the lower part of the regeneration settling zone 2B, specifically as shown... Figure 1 As shown, the upper part of the regeneration settling zone 2B is cylindrical, and the lower part is conical with a concave center (the angle with the riser can be set to 30-60°). This structure facilitates the uniform dispersion of catalyst solid particles along the circumferential direction, and the catalyst flows downward into the sulfidation zone 3B (i.e., the radial reaction zone) through the symmetrically distributed catalyst feed pipe 23. While supplying oxidized catalyst to the sulfidation zone 3B of the sulfidation unit 3, the bottom of this bed (i.e., the bottom of the narrowing section 22) can also leave sufficient gas collection space for the upper gas collection chamber 3A of the sulfidation unit 3, creating more favorable conditions for the "radial inflow" of the sulfidation zone.

[0060] The following is for reference. Figures 1 to 6 Starting with reforming unit 1, the reforming process, regeneration process, and vulcanization process are explained in detail:

[0061] Reforming Process: Reforming reaction zone 1B is a fluidized bed. The specific reaction process is as follows: The sulfidated catalyst is uniformly fed into the reforming settling zone 1A through symmetrically distributed feed ports 303, and flows downwards to the reforming reaction zone 1B to participate in the reaction. H2S and CH4 are pre-mixed by gas mixer 110 and then enter from the bottom of the bed in reforming reaction zone 1B. They are uniformly dispersed by gas distributor 11, flowing counter-currently upwards to contact the sulfidated catalyst and undergo a reforming reaction. The deactivated catalyst after the reaction enters the second heat exchanger E2 through the waiting inclined tube 14 to preheat the CH4 feed gas before entering the regeneration zone 2A (i.e., the riser reactor) for oxidative regeneration. The gaseous products after the reaction and the unreacted H2S and CH4 are separated in the first cyclone separator 13. The solid catalyst particles return to the catalyst bed in reforming reaction zone 1B, while the separated gas stream is discharged from the top of the first cyclone separator 13 into reforming reaction zone 1B and enters the first heat exchanger E1 to react with the sulfidated gas (i.e., the gaseous products). Figure 2 The H2S gas (30 rpm) before the inlet of the sulfidation gas undergoes heat exchange to recover some energy.

[0062] Regeneration Process: Regeneration zone 2A is an upward-flowing riser. The specific reaction process is as follows: Deactivated catalyst from the upper inclined tube 14 enters the second heat exchanger E2 for heat recovery (preheating the CH4 feed gas), and then enters regeneration zone 2A (i.e., the riser reactor) at a certain flow rate under the action of regulating valve 141. On one hand, air is used as the fluidizing gas to lift and transport the deactivated catalyst upwards; on the other hand, air is used to oxidize the catalyst at high temperature and burn off the carbon deposits, transforming the deactivated catalyst into an oxidized state. The stream obtained from the riser outlet undergoes gas-solid separation in the second cyclone separator 21. The regenerated coke flue gas is discharged from the top of the regeneration zone and enters the third heat exchanger E3 to exchange heat with the H2S feed gas (this portion of H2S feed gas can be used as feed gas for the reforming reaction zone 1B) for energy recovery. The solid oxidized catalyst obtained from the second cyclone separator 21 enters the regeneration settling zone 2B, which has a narrowed bottom, and flows along the catalyst inlet pipe 23 of the sulfidation zone (see reference). Figure 2 , 3 4) Enter the vulcanization zone downwards.

[0063] Sulfidation Process: Sulfidation zone 3B is a gas-solid radial reaction zone. Specifically, the oxidized catalyst enters the symmetrically arranged sulfidation zone 3B (i.e., the radial reaction zone) from the regeneration settling zone 2B. The catalyst moves vertically downwards in sulfidation zone 3B and is discharged under the control of the bottom outlet regulating valve 304, entering the reforming settling zone 1A, and then downwards into the reforming reaction zone 1B for reaction. The sulfiding gas enters from the upper gas collecting zone 3A and is baffled by the upper baffle plate 31, lower baffle plate 32, and arc-shaped baffle plate 33, guiding the sulfiding gas to the inner wall 301 of sulfidation zone 3B (reference). Figure 2The gas passes radially through the inner wall 301 and comes into radial contact with the catalyst in the sulfidation zone 3B to undergo a sulfidation reaction. The reacted gas continues to pass radially through the outer wall 302 and is collected in the lower gas collection zone 3C under the guidance of the arc-shaped isolation plate 33 and the lower isolation plate 32. The sulfidated gas then enters the interior of the reforming reaction zone 1B through the sulfidation gas outlet 305 and, under the action of the gas outlet regulating valve 306, flows downward along the sulfidation gas outlet pipe 12, where it undergoes a reforming reaction with the catalyst together with the raw material gas entering from the bottom.

[0064] like Figure 7 As shown, the present invention also provides a hydrogen sulfide and methane reforming system, employing the aforementioned hydrogen sulfide and methane reforming unit R1, and further including a CS2 separation unit, an H2S separation unit, and an H2 purification unit. The CS2 separation unit receives the reaction products from the hydrogen sulfide and methane reforming unit R1, and obtains the CS2 product after flash evaporation and cryogenic distillation. Preferably, but not limitingly, the CS2 separation unit may include... Figure 7 The system comprises a primary flash tank D1, a secondary flash tank D2, and a distillation column D3. The H2S separation unit receives a gaseous stream containing H2S, CH4, and H2 from the CS2 separation unit. High-precision H2S separation is achieved through low-temperature methanol washing, and the separated H2S is recycled as feed gas for the hydrogen sulfide and methane reforming unit R1. Preferably, but not limitingly, the H2S separation unit may include an H2S absorption tower S1, a flash tank S2, and a methanol regeneration tower S3. The H2 purification unit receives a gaseous stream containing CH4 and H2 from the H2S separation unit and produces high-purity hydrogen through pressure swing adsorption (PSA). The separated CH4 is recycled as feed gas for the hydrogen sulfide and methane reforming unit R1. The H2 purification unit is preferably a PSA unit.

[0065] refer to Figures 1 to 7 As shown, the present invention also provides a method for reforming hydrogen sulfide and methane, using the aforementioned system, and comprising at least the following steps:

[0066] Step S101, Reforming Reaction: In the fluidized bed reforming reaction zone 1B, H2S and CH4 are used as fluidizing gases, and under the action of a sulfide-state catalyst, H2S and CH4 are reformed to produce H2 and CS2. Operating conditions for the reforming reaction: The preferred reaction temperature is 800℃, and the preferred reaction pressure is atmospheric pressure to 0.8 MPa. The catalyst used in the reforming reaction is preferably a supported catalyst, and the active component can be one or more of molybdenum oxide, iron oxide, cobalt oxide, etc.; the support can be one or more of alumina, silicon oxide, titanium oxide, silica-alumina molecular sieves, etc.

[0067] Step S102, regeneration reaction: using air as the fluidizing gas, the catalyst from the reforming reaction zone 1B, which has been deactivated, is driven upward through the regeneration zone 2A constructed by the riser and undergoes oxidative regeneration.

[0068] Step S103, Sulfidation reaction: The oxidized and regenerated catalyst is conveyed downward to the sulfidation zone 3B and comes into contact with the radially moving H2S gas in the sulfidation zone 3B. The oxidized catalyst is pre-sulfided with H2S as the sulfidation gas to generate a sulfidated catalyst, which is then conveyed downward to the reforming settling zone 1A; return to step S101 to form a cycle.

[0069] The method may also include the following steps:

[0070] Step S104, CS2 separation process: The reaction product after the reforming reaction in step S101 is subjected to two-stage flash evaporation and low-temperature distillation to obtain the CS2 product.

[0071] Step S105, H2S separation process: The gaseous stream containing H2S, CH4 and H2 separated in step S104 is subjected to high-precision H2S separation by low-temperature methanol washing. The separated H2S is recycled as the raw material gas for step S101.

[0072] In step S106, the gaseous stream containing CH4 and H2 separated in step S105 is used to produce high-purity hydrogen through pressure swing adsorption; the separated CH4 is recycled as the feed gas in step S101.

[0073] Example 1

[0074] refer to Figures 1 to 7 The sulfidated catalyst is uniformly fed into the reforming settling zone 1A through symmetrically distributed feed ports 303, and flows downward to the reforming reaction zone 1B to participate in the reaction. H2S (0.36 mol / h) and CH4 (0.19 mol / h) are pre-mixed and enter from the bottom of the bed in the reforming reaction zone 1B. They are uniformly dispersed by the gas distributor 11, flow countercurrently upward to contact the sulfidated catalyst, and undergo a reforming reaction at 800℃ and 0.8MPa to generate H2 and CS2. The gaseous products after the reaction and the unreacted H2S and CH4 are separated into gas and solid in the first cyclone separator 13. The solid catalyst particles are returned to the catalyst bed in the reforming reaction zone 1B, and the separated gas stream is discharged from the top of the first cyclone separator into the reforming reaction zone 1B and enters the first heat exchanger E1 to exchange heat with the sulfided gas that is about to enter the upper gas collection zone 3A of the sulfidation unit 3, recovering some energy.

[0075] The deactivated catalyst after the reaction enters the second heat exchanger E2 through the upper inclined tube 14 to preheat the CH4 feed gas for heat recovery. Then, under the action of the regulating valve 141, it enters the regeneration zone 2A to undergo an oxidation reaction with air at 800°C and burn off the carbon deposits, transforming the deactivated catalyst into an oxidized state. The stream obtained from the outlet of the riser of the regeneration zone 2A undergoes gas-solid separation in the second cyclone separator. The regenerated coke flue gas is discharged from the top of the riser and enters the third heat exchanger E3 to exchange heat with H2S gas. The solid oxidized catalyst obtained from the second cyclone separator 21 enters the regeneration settling zone 2B, which has a conical bottom, and then enters the symmetrically arranged sulfidation zone 3B vertically downward through the catalyst inlet pipe 23 of the sulfidation zone. Here, the catalyst undergoes a sulfidation reaction and is transformed into a sulfidated catalyst. Under the control of the bottom outlet regulating valve 304, it is discharged and enters the reforming settling zone 1A, and then enters the bed of the reforming reaction zone 1B for reaction.

[0076] After heat exchange in the first heat exchanger E1, the sulfided gas enters from the upper gas collection zone 3A. Under the action of the upper isolation plate 31, the lower isolation plate 32, and the arc-shaped isolation plate 33, the sulfided gas is baffled and guided to the inner wall 301 of the sulfidation zone 3B. It passes radially through the inner wall and comes into radial contact with the catalyst to carry out the sulfidation reaction. The gas after the reaction continues to pass radially through the outer wall 302 and is collected in the lower gas collection zone 3C under the guidance of the arc-shaped isolation plate 33 and the lower isolation plate 32. The sulfided gas enters the interior of the reforming reaction zone 1B through the gas outlet 305 under the action of the regulating valve 306, and together with the bottom raw material gas, it undergoes a reforming reaction with the catalyst.

[0077] The catalyst is circulated within the same unit R1 according to functional zones for reforming, regeneration, and sulfidation, achieving a continuous reaction process. The reforming reaction product is compressed to an outlet pressure of 3.02 MPa, cooled to an outlet temperature of 20°C by the first heat exchanger E1, and then passes through a primary flash tank D1 for gas-liquid separation. The gas phase mainly contains H2, CH4, H2S, and a small amount of CS2, while the liquid phase mainly contains CS2 and some H2S that is easily soluble in CS2. The gas phase exiting the primary flash tank D1 is cooled to -20°C by a heat exchanger to further liquefy the CS2, and then passes through a secondary flash tank D2 to separate the liquefied CS2. The gas phase exiting the secondary flash tank D2 is sent to an H2S separation unit. The liquid phase from the two flashes enters a CS2 distillation column D3. The H2S obtained from the top of the column after distillation is recycled back to the reforming unit R1 of this invention, and the bottom of the column yields a CS2 product with a mass fraction of 98.9 wt.% (0.17 mol / h).

[0078] The gaseous stream from the CS2 separator is cooled to -20°C via a heat exchanger and then enters the H2S absorption tower S1 as rich gas, where it undergoes countercurrent absorption with the lean liquid. Methanol is used as the absorbent in the lean liquid, and the temperature is -40°C and the pressure is 3.0 MPa. The lean gas exiting the top of the H2S absorption tower S1 enters the H2 purification unit. The rich liquid at the bottom of the tower is depressurized to 0.4 MPa and then enters the flash evaporator S2 to flash non-condensable gases, which are then returned to the absorption tower S1. The liquid phase from the flash evaporator S2 is then heat-exchanged and enters the methanol regeneration tower S3 for methanol regeneration. The gaseous stream at the top of the tower is returned to the reforming unit R1 as recycled H2S, and the stream from the bottom of the tower is regenerated methanol, which is recycled back to the H2S absorption tower S1 as lean liquid.

[0079] The H2 purification unit employs a process flow of 12 adsorption towers, 2 adsorption tower feeds, and 6 pressure equalization processes. The feed gas, at a temperature of 20℃ and a pressure of 3.0 MPa, enters from the bottom of the adsorption towers, flows upward through the bed, and exits from the top of the adsorption towers as hydrogen gas with a purity of 98.98% (0.64 mol / h).

[0080] The foregoing description of specific exemplary embodiments of the present invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. Any simple modifications, equivalent changes, and alterations made to the foregoing exemplary embodiments should fall within the scope of protection of the present invention.

Claims

1. A hydrogen sulfide and methane reforming apparatus, characterized in that, include: A reforming unit is located at the bottom of the device and has a reforming settling zone and a reforming reaction zone; In the fluidized bed reforming reaction zone, H2S and CH4 are used as fluidizing gases, and under the action of a sulfurized catalyst, H2S and CH4 are reformed to generate H2 and CS2. The regeneration unit has a regeneration zone and a regeneration settling zone located at the top of the device; the regeneration zone is the internal space of a riser pipe that runs through the bottom of the device and extends upward to the regeneration settling zone, and is used to drive the deactivated catalyst from the reforming reaction zone upward and perform oxidative regeneration using air as the fluidizing gas; The sulfidation unit has an upper gas collection zone, a sulfidation zone, and a lower gas collection zone for guiding H2S gas through a deflection process. The sulfidation zone is a radial reaction zone in which the oxidized catalyst moving axially downward from the regeneration settling zone comes into contact with the radially moving H2S gas. This is used to pre-sulfidate the oxidized catalyst with H2S as the sulfidation gas, generating a sulfidated catalyst which is then transported downward to the reforming settling zone.

2. The hydrogen sulfide and methane reforming apparatus according to claim 1, characterized in that, The vulcanization zone is a radial reactor structure with multiple evenly spaced perforated walls. The radial reactor has an inner wall and an outer wall, which are used to allow H2S gas that has been deflected here to pass through the inner and outer walls, forming H2S gas that runs radially within the vulcanization zone.

3. The hydrogen sulfide and methane reforming apparatus according to claim 2, characterized in that, The upper gas collecting zone, the sulfidation zone, and the lower gas collecting zone are collectively constructed as a baffle channel for H2S gas.

4. The hydrogen sulfide and methane reforming apparatus according to claim 3, characterized in that, The baffle channel is constructed by an upper baffle plate, a lower baffle plate, and an arc-shaped baffle plate; the upper baffle plate is located at the bottom of the upper gas collection zone and on the side of the device wall, the lower baffle plate is located at the top of the lower gas collection zone and on the side of the device axis, and the arc-shaped baffle plate is arranged circumferentially between adjacent radial reactors.

5. The hydrogen sulfide and methane reforming apparatus according to claim 1, characterized in that, The lower gas collection zone of the sulfidation unit is provided with a gas outlet at the bottom, and the gas outlet pipeline extends downward to the fluidized bed of the reforming reaction zone, and the pipeline is provided with a gas outlet regulating valve; the bottom of the sulfidation zone is provided with a catalyst feed port, and the feed port outlet pipeline extends downward to the reforming settling zone, and the pipeline is provided with a feed regulating valve.

6. The hydrogen sulfide and methane reforming apparatus according to claim 1, characterized in that, The reforming reaction zone is equipped with a first cyclone separator at the top, which is used to separate the high-temperature reforming reaction gaseous products from the catalyst particles. The separated catalyst particles are returned to the fluidized bed of the reforming reaction zone.

7. The hydrogen sulfide and methane reforming apparatus according to claim 6, characterized in that, The high-temperature reforming reaction gaseous products exchange heat with H2S gas, which is prepared to enter the upper gas collecting zone for pre-sulfurization, through the first heat exchanger.

8. The hydrogen sulfide and methane reforming apparatus according to claim 1, characterized in that, The catalyst outlet at the bottom of the reforming reaction zone is connected to the bottom of the riser through two sections of preheating inclined tubes; a second heat exchanger is provided between the two sections of preheating inclined tubes to preheat the CH4 feed gas that is about to enter the reforming reaction zone with the high-temperature deactivated catalyst.

9. The hydrogen sulfide and methane reforming apparatus according to claim 8, characterized in that, The preheated CH4 feed gas is mixed with the preheated H2S feed gas through a gas mixer and then introduced into a gas distributor located at the bottom of the reforming reaction zone.

10. The hydrogen sulfide and methane reforming apparatus according to claim 1, characterized in that, The upper part of the regeneration settling zone is equipped with a second cyclone separator, which is used to receive the oxidized catalyst from the regeneration zone and perform gas-solid separation; the separated coke flue gas is discharged from the device and the H2S feed gas is preheated through a third heat exchanger.

11. The hydrogen sulfide and methane reforming apparatus according to claim 10, characterized in that, The lower part of the regeneration settling zone is provided with a bed with a narrow diameter, which is used to transport the oxidized catalyst to the sulfidation zone of the sulfidation unit, while the bottom of the bed leaves enough gas collection space for the upper gas collection chamber of the sulfidation unit.

12. A hydrogen sulfide and methane reforming system, characterized in that, The apparatus according to any one of claims 1 to 11 further comprises: The CS2 separation unit receives the reaction products from the hydrogen sulfide and methane reforming unit, and obtains the CS2 product after flash evaporation and cryogenic distillation. The H2S separation unit receives a gaseous stream containing H2S, CH4 and H2 from the CS2 separation unit, and performs high-precision separation of H2S by low-temperature methanol washing. The separated H2S is recycled as feed gas for the hydrogen sulfide and methane reforming unit. The H2 purification unit receives a gaseous stream containing CH4 and H2 from the H2S separation unit and produces high-purity hydrogen through pressure swing adsorption. The separated CH4 is recycled as feed gas for the hydrogen sulfide and methane reforming unit.

13. The hydrogen sulfide and methane reforming system according to claim 12, characterized in that, The CS2 separation unit includes a primary flash tank, a secondary flash tank, and a distillation column; the H2S separation unit includes an H2S absorption column, a flash tank, and a methanol regeneration column; the H2 purification unit is a PSA unit.

14. A method for reforming hydrogen sulfide with methane, characterized in that, The system described in claim 12 or 13 includes the following steps: A. In a fluidized bed reforming reaction zone, H2S and CH4 are used as fluidizing gases, and under the action of a sulfurized catalyst, H2S and CH4 are reformed to produce H2 and CS2. B. Using air as the fluidizing gas, the catalyst from the reforming reaction zone, after being deactivated, is driven upward through the regeneration zone constructed by the riser and undergoes oxidative regeneration. C. The oxidized and regenerated catalyst is conveyed downward to the sulfidation zone and comes into contact with radially moving H2S gas in the sulfidation zone. The oxidized catalyst is pre-sulfided using H2S as the sulfidation gas to generate a sulfidated catalyst, which is then conveyed downward to the reforming settling zone; return to step A to form a cycle.

15. The method for reforming hydrogen sulfide and methane according to claim 14, characterized in that, Operating conditions for the reforming reaction: reaction temperature 800℃, reaction pressure atmospheric pressure to 0.8 MPa.

16. The method for reforming hydrogen sulfide and methane according to claim 14, characterized in that, The catalyst used in the reforming reaction is a supported catalyst, with the active component being one or more of molybdenum oxide, iron oxide, and cobalt oxide; the support is one or more of alumina, silicon oxide, titanium oxide, and silica-alumina molecular sieves.

17. The method for reforming hydrogen sulfide and methane according to claim 14, characterized in that, The method further includes the following steps: D. Perform two-stage flash evaporation and low-temperature distillation on the reaction product after the reforming reaction in step A to obtain the CS2 product; E. The gaseous stream containing H2S, CH4 and H2 separated in step D is subjected to high-precision H2S separation by low-temperature methanol washing, and the separated H2S is recycled as the raw material gas in step A. F. The gaseous stream containing CH4 and H2 separated in step E is used to produce high-purity hydrogen through pressure swing adsorption; the separated CH4 is recycled as the raw material gas in step A.

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