Method and device for preparing sulfur by promoting gasification of carbon-based material and reduction of sulfur dioxide

Abstract

The invention relates to a method and device for promoting carbon-based material gasification and sulfur dioxide reduction to prepare sulfur, and the method comprises the following steps: adding a carbon-based material, introducing carbon dioxide, introducing sulfur dioxide or carbonyl sulfide and hydrogen sulfide, and carrying out gasification reaction on the carbon-based material to obtain gasified gas; introducing gasified gas, introducing sulfur dioxide, carrying out a reduction reaction of the sulfur dioxide to obtain reducing gas, and returning part of the reducing gas to the gasification reaction of the carbon-based material; introducing other reducing gas, introducing sulfur dioxide, and carrying out Claus reaction to obtain product gas; product gas is cooled, sulfur is recycled, the rest of carbon dioxide and water vapor are secondarily cooled, part of carbon dioxide is returned to the gasification reaction of the carbon-based material, and the rest of carbon dioxide is recycled. Compared with the prior art, the method has the advantages of efficiently initiating the carbon-based material, promoting the reduction conversion of sulfur dioxide to prepare sulfur, reducing the energy consumption of the gasification section, and improving the gasification reaction rate of the gasification section and the sulfur dioxide reduction rate of the reduction section.

Description

Technical Field

[0001] The invention belongs to the technical field of material processing, energy and environmental protection, and relates to a method and a device for promoting the gasification of carbon-based materials and reducing sulfur dioxide to produce sulfur. Background Art

[0002] my country's energy structure is mainly coal, and the sulfur in coal will produce a large amount of sulfur dioxide gas during the combustion process. At present, there are many types of sulfur dioxide treatment technologies, among which the most mature technology is the limestone gypsum method. However, the limestone gypsum method not only consumes a large amount of limestone, but also the by-product gypsum is currently in a state of oversupply. Long-term stacking will pose a risk of environmental pollution. Reducing sulfur dioxide to sulfur is a relatively effective sulfur dioxide treatment method. Compared with other desulfurization products, sulfur has the smallest molecular weight and is insoluble in water in solid form, which is convenient for transportation and storage, can effectively control safety risks, and has high added value. However, the reaction temperature of sulfur dioxide reduction to sulfur is high, the side reactions are difficult to control, and the types of by-products are relatively complex. The gases produced during the gasification of carbon-based materials mainly include carbon monoxide, hydrogen, methane, carbon dioxide and nitrogen. The mixture of carbon monoxide and hydrogen is called synthesis gas, which is the main product of carbon-based material gasification. However, this process has problems such as high gasification reaction temperature and poor selectivity of reduction products.

[0003] The method of catalytically reducing sulfur dioxide using gasification gas of carbon-based materials such as coal, coke or biomass is relatively economical, but there are also problems such as high gasification reaction temperature, poor selectivity of reduction products and poor sulfur quality. Patent CN103303872A discloses a system device and method for recovering sulfur dioxide from flue gas to produce sulfur, the method is that the absorption and pyrolysis unit absorbs and pyrolyzes the flue gas to obtain pure sulfur dioxide gas, and the reduction unit converts sulfur dioxide into elemental sulfur by catalytic reaction. However, the patent has the disadvantages of long production process, complex process and high operating cost. Patent CN111821851A discloses a system and method for reducing sulfur dioxide-containing gas by binary method, the system includes: a gasifier, which is used for gasification reaction of carbon-based solid fuel and gasifying agent, and is used for binary reduction of sulfur dioxide using coal gas and semi-coke produced by the gasification reaction. However, the reaction temperature of this patent is high and the energy consumption is large. Summary of the invention

[0004] The purpose of the present invention is to overcome at least one of the defects of the above-mentioned prior art, such as the high gasification temperature of conventional carbon-based raw materials and the difficulty in effectively reducing sulfur dioxide, and to provide a method and device for promoting the gasification of carbon-based materials and reducing sulfur dioxide to produce sulfur. The present invention efficiently initiates carbon-based materials, promotes the reduction and conversion of sulfur dioxide to produce sulfur, reduces the energy consumption of the gasification section, and increases the gasification reaction rate in the gasification section and the sulfur dioxide reduction rate in the reduction section.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] One of the technical solutions of the present invention is to provide a method for promoting the gasification of carbon-based materials and reducing sulfur dioxide to produce sulfur, the method comprising the following steps:

[0007] S1. Add carbon-based materials, introduce gasification raw gas or recycled gas containing carbon dioxide (CO2), introduce reduction raw gas containing sulfur dioxide (SO2) or reduction gas containing carbonyl sulfide (COS) or hydrogen sulfide (H2S), and perform gasification reaction of carbon-based materials, using carbon dioxide as a gasifying agent, using sulfur dioxide or its reduction product hydrogen sulfide or carbonyl sulfide as a promoter, and promoting the gasification reaction of carbon-based materials to obtain gasified gas, wherein hydrocarbons in the carbon-based materials exist in the form of carbon monoxide (CO) and hydrogen (H2) in the gasified gas, and sulfur in the gasified gas exists in the form of hydrogen sulfide or carbonyl sulfide;

[0008] S2, introducing gasification gas, introducing reduction raw gas containing sulfur dioxide, and carrying out reduction reaction of sulfur dioxide. The hydrogen sulfide and carbonyl sulfide coexisting in the gasification gas significantly promote the reaction of carbon monoxide and hydrogen reducing sulfur dioxide, and generate one or more sulfur-containing gases of hydrogen sulfide and carbonyl sulfide. Part of the reducing gas is returned to the gasification reaction of the carbon-based material to promote the hydrolysis of the carbon-based material, and the rest is introduced with water vapor to hydrolyze the carbonyl sulfide generated by the reduction of sulfur dioxide, so that all sulfides exist in the form of hydrogen sulfide, and the reducing gas is obtained. The reducing gas includes hydrogen sulfide, carbon dioxide, and water vapor (H2O);

[0009] S3, introducing the remaining reducing gas, introducing the reducing raw gas containing sulfur dioxide, and carrying out Claus reaction, sulfur dioxide and hydrogen sulfide quickly undergo low-temperature Claus reaction to generate sulfur, and obtain product gas, which includes sulfur vapor, carbon dioxide, and water vapor;

[0010] S4. The product gas is cooled, and the sulfur vapor in the product gas is condensed into liquid for recovery. The remaining carbon dioxide and water vapor are cooled again, and the water vapor is condensed into liquid. Part of the carbon dioxide is returned to the gasification reaction of the carbon-based material to participate in the gasification reaction, and the rest is recovered for treatment.

[0011] Furthermore, in step S1, the carbon-based raw material is selected from one or more of coal, lignite, coke, and biomass, the volume of the reducing raw gas or the sulfur-containing gas in the reducing gas is 1-10% of the carbon dioxide in the gasification raw gas or the recovered gas, and the sum of the volume proportions of carbon monoxide and hydrogen in the gasification gas is greater than 50%.

[0012] Furthermore, the gasification raw gas in step S1 also includes one or more auxiliary agents in oxygen (O2) and water vapor, and the volume of the auxiliary agent in the gasification raw gas is 5-20% of carbon dioxide. Oxygen or water vapor and carbon dioxide are used to co-gasify carbon-based materials to produce hydrogen.

[0013] As a preferred technical solution, in step S1, gasification raw gas containing carbon dioxide is introduced at the beginning of operation, and recovery gas containing carbon dioxide is introduced in subsequent operation, and the space velocity of the gasification raw gas is 1000-6000 mL / (min·kg).

[0014] As a preferred technical solution, in step S1, a reducing raw gas containing sulfur dioxide is introduced at the beginning of the operation, and a reducing gas containing carbonyl sulfide or hydrogen sulfide is introduced in the subsequent operation, and the space velocity of the reducing raw gas is 1000-6000 mL / (min·kg).

[0015] Furthermore, the temperature of the gasification reaction in step S1 is 700-950°C.

[0016] As a preferred technical solution, in step S1, residual ash residue from the gasification reaction of the carbon-based material is discharged.

[0017] As a preferred technical solution, after step S1, the temperature of the gasified gas is cooled to 450-550°C to recover the waste heat.

[0018] As a preferred technical solution, after step S1, the gasification gas is dusted and ash is discharged, and the particulate matter brought out by the gasification gas is removed.

[0019] Furthermore, the catalyst for the reduction reaction in step S2 is selected from sulfides of one or more metals selected from cobalt (Co), molybdenum (Mo), and tungsten (W). The volume of sulfur dioxide in the reducing raw gas is 33% of the sum of carbon monoxide and hydrogen in the gasification gas, and sulfur dioxide can just react completely with carbon monoxide and hydrogen.

[0020] As a preferred technical solution, the space velocity of the reducing raw gas in step S2 is 1000-6000 mL / (min·kg).

[0021] Furthermore, the volume ratio of water vapor to sulfur dioxide introduced in step S2 is (1-1.2):1, and the water vapor hydrolyzes carbonyl sulfide produced by the reduction of sulfur dioxide, so that all sulfur-containing gases exist in the form of hydrogen sulfide.

[0022] Furthermore, the temperature of the reduction reaction in step S2 is 400-500°C.

[0023] Furthermore, the catalyst for the Claus reaction in step S3 uses an aluminum-based catalytic material modified with a cobalt (Co) or molybdenum (Mo) active component, and the volume of sulfur dioxide in the reducing raw gas is 50% of the hydrogen sulfide in the reducing gas, so that sulfur dioxide and hydrogen sulfide react completely.

[0024] As a preferred technical solution, the space velocity of the reducing raw gas in step S3 is 1000-6000 mL / (min·kg).

[0025] Furthermore, the temperature of the Claus reaction in step S3 is 250-400°C.

[0026] One of the technical solutions of the present invention is to provide a device for promoting the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur. The device implements the method to promote the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur. The device comprises a gasification section, a reduction section and a reaction section connected in sequence. A gasification gas cooling unit is arranged between the gasification section and the reduction section. A sulfur cooling unit and a carbon dioxide cooling unit are arranged in sequence after the reaction section. The reduction section is connected to the regasification section. The carbon dioxide cooling unit is connected to the regasification section.

[0027] In the gasification section, carbon-based materials, carbon dioxide, and sulfur dioxide or its reduction product hydrogen sulfide or carbonyl sulfide are mixed to perform a gasification reaction of the carbon-based materials to obtain gasification gas containing carbon monoxide, hydrogen, hydrogen sulfide, carbonyl sulfide, and carbon dioxide. The gasification gas cooling unit cools the gasification gas.

[0028] In the reduction section, the gasification gas and sulfur dioxide are mixed to carry out a reduction reaction of sulfur dioxide to obtain a reduction gas, part of which is returned to the gasification section, and the rest is sent to the reaction section.

[0029] In the reaction section, reducing gas and sulfur dioxide are mixed to carry out Claus reaction to obtain product gas. In the sulfur cooling unit, the product gas is cooled to separate sulfur vapor from carbon dioxide and water vapor to recover sulfur. In the carbon dioxide cooling unit, carbon dioxide and water vapor are cooled to separate carbon dioxide and water vapor, part of the carbon dioxide is returned to the gasification section, and the rest is recovered for treatment.

[0030] As a preferred technical solution, the gasification section adopts one or more of a fixed bed, a moving bed or a fluidized bed.

[0031] As a preferred technical solution, the reduction section adopts one or more of a fixed bed, a moving bed or a fluidized bed.

[0032] As a preferred technical solution, the reaction section adopts one or more of a fixed bed, a moving bed or a fluidized bed.

[0033] As a preferred technical solution, the gasification gas cooling unit recovers waste heat.

[0034] As a preferred technical solution, the sulfur cooling unit recovers waste heat.

[0035] As a preferred technical solution, the sulfur cooling unit is connected to a sulfur recovery unit, and sulfur is recovered through the sulfur recovery unit.

[0036] As a preferred technical solution, the carbon dioxide cooling unit recovers waste heat.

[0037] As a preferred technical solution, the carbon dioxide cooling unit is connected to a carbon dioxide recovery unit, and the carbon dioxide is recovered through the carbon dioxide recovery unit.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] (1) The present invention uses a gasification-reduction combined device system to utilize the reduction sulfurization product to enhance the gasification of carbon-based materials by carbon dioxide, and utilizes the coexisting sulfur-containing gas and sulfur dioxide feed gas to generate active sulfur species to enhance the deep reduction of sulfur dioxide by gasification gas, thereby efficiently initiating carbon-based materials and promoting the reduction conversion of sulfur dioxide to produce sulfur;

[0040] (2) Through the application of the present invention, the temperature required for the gasification stage can be reduced from the conventional 1000°C or above to below 950°C by using the active sulfur generated by partial reflux of the sulfidation product and pre-reduction of the raw gas, and the temperature required for the reduction stage can be reduced to below 500°C, and the catalyst activity can be kept stable for a long time; the separated carbon dioxide can be partially returned to the gasification stage and recycled as a gasifying agent, and the excess carbon dioxide has a high purity and can be directly recycled and utilized as a resource, and the energy consumption of the gasification stage is significantly reduced, the gasification reaction rate of the gasification stage and the sulfur dioxide reduction rate of the reduction stage are increased, and the separation and recycling of carbon dioxide can be achieved;

[0041] (3) The process of the present invention is simple and has low operating costs. By utilizing active sulfur, the selectivity of the reduction product can be effectively improved, thereby facilitating the high-value resource utilization of sulfur dioxide, a by-product of industrial flue gas in metallurgy and other industrial fields, while achieving efficient sulfur preparation and industrial carbon emission reduction, and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 It is a schematic structural diagram of a device for promoting gasification of carbon-based materials and reduction of sulfur dioxide to produce sulfur in an embodiment of the present invention.

[0043] Description of the markings in the figure:

[0044] 1—gasification section, 2—gasification gas cooling unit, 3—reduction section, 4—reaction section, 5—sulfur cooling unit, 6—carbon dioxide cooling unit, 7—sulfur recovery unit, 8—carbon dioxide recovery unit. DETAILED DESCRIPTION

[0045] The present invention is described in detail below in conjunction with specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0046] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", "third", etc. are used to describe common objects, which only refer to different instances of the same object, and are not intended to imply that the objects described in this way must adopt a given order, whether in time, space, order or any other way.

[0047] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0048] Unless otherwise specified, the equipment used in the following examples are all conventional equipment in the art; the reagents used are all commercially available products or prepared by conventional methods in the art unless otherwise specified. Anything not described in detail in the following examples can be achieved by conventional experimental means in the art.

[0049] A device for promoting gasification of carbon-based materials and reduction of sulfur dioxide to produce sulfur, such as Figure 1 As shown, it includes a gasification section 1, a reduction section 3 and a reaction section 4 connected in sequence, a gasification gas cooling unit 2 is arranged between the gasification section 1 and the reduction section 3, a sulfur cooling unit 5 and a carbon dioxide cooling unit 6 are arranged in sequence after the reaction section 4, the reduction section 3 is connected to the regasification section 1, the carbon dioxide cooling unit 6 is connected to the regasification section 1, the sulfur cooling unit 5 is connected to the sulfur recovery unit 7, the carbon dioxide cooling unit 6 is connected to the carbon dioxide recovery unit 8,

[0050] In the gasification section 1, carbon-based materials, carbon dioxide, and sulfur dioxide or its reduction product hydrogen sulfide or carbonyl sulfide are mixed to perform a gasification reaction of the carbon-based materials to obtain gasification gas containing carbon monoxide, hydrogen, hydrogen sulfide, carbonyl sulfide, and carbon dioxide. The gasification gas is cooled in the gasification gas cooling unit 2 to recover the waste heat.

[0051] In the reduction section 3, the gasification gas and sulfur dioxide are mixed to carry out a reduction reaction of sulfur dioxide to obtain a reduction gas. Part of the reduction gas is returned to the gasification section 1, and the rest is sent to the reaction section 4.

[0052] In the reaction section 4, the reducing gas and sulfur dioxide are mixed to carry out Claus reaction to obtain product gas. The product gas is cooled in the sulfur cooling unit 5 to recover the waste heat, separate sulfur vapor from carbon dioxide and water vapor, and recover sulfur through the sulfur recovery unit 7. In the carbon dioxide cooling unit 6, carbon dioxide and water vapor are cooled to recover the waste heat, separate carbon dioxide and water vapor, and part of the carbon dioxide is returned to the gasification section 1, and the rest is recovered and processed through the carbon dioxide recovery unit 8.

[0053] Embodiment 1:

[0054] A method for promoting the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur, using the above device to promote the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur, the specific steps are as follows:

[0055] S1. In the gasification section 1, a carbon-based material is added, a gasification raw gas or a recycled gas containing carbon dioxide (CO2) is introduced, a reduction raw gas containing sulfur dioxide (SO2) or a reduction gas containing carbonyl sulfide (COS) or hydrogen sulfide (H2S) is introduced, and a gasification reaction of the carbon-based material is carried out. Carbon dioxide is used as a gasifying agent, and sulfur dioxide or its reduction product hydrogen sulfide or carbonyl sulfide is used as a promoter to promote the gasification reaction of the carbon-based material to obtain a gasified gas. The hydrocarbons in the carbon-based material exist in the form of carbon monoxide (CO) and hydrogen (H2) in the gasified gas, and the sulfur in the gasified gas exists in the form of hydrogen sulfide or carbonyl sulfide;

[0056] The gasification section 1 uses a fixed bed reactor with an inner diameter of 300 mm and a length of 1.5 m;

[0057] The carbon-based raw material is 500g of coke with a particle size of 4±1mm. The volume of the reducing raw gas and the sulfur-containing gas in the reducing gas is 10% of the carbon dioxide in the gasification raw gas and the recovered gas. The volume proportions of carbon monoxide, hydrogen, carbon dioxide, hydrogen sulfide and carbonyl sulfide in the gasification gas are 60%, 5%, 6%, 3% and 3% respectively.

[0058] At the beginning of the operation, the gasification raw gas containing carbon dioxide is introduced, and the recovery gas containing carbon dioxide is introduced in the subsequent operation. The composition of the gasification raw gas is pure carbon dioxide, the space velocity is 2000mL / (min·kg), and the space velocity of the returned recovery gas is 3000mL / (min·kg);

[0059] At the beginning of the operation, a reducing raw gas containing sulfur dioxide is introduced, and a reducing gas containing carbonyl sulfide or hydrogen sulfide is introduced in the subsequent operation. The composition of the reducing raw gas is sulfur dioxide and nitrogen in a volume ratio of 1:2, the space velocity is 2500mL / (min·kg), and the space velocity of the returning reducing gas is 3000mL / (min·kg);

[0060] The temperature of the gasification reaction is 900°C;

[0061] Discharging ash residue remaining from the gasification reaction of carbon-based materials;

[0062] After step S1, the temperature of the gasified gas is cooled to 500° C. in the gasified gas cooling unit 2;

[0063] After step S1, in the gasification gas cooling unit 2, the gasification gas is dusted and ash is discharged, and the particulate matter brought out by the gasification gas is removed;

[0064] S2, in the reduction section 3, gasification gas is introduced, and reduction raw gas containing sulfur dioxide is introduced to carry out reduction reaction of sulfur dioxide. The hydrogen sulfide and carbonyl sulfide coexisting in the gasification gas significantly promote the reaction of carbon monoxide and hydrogen reducing sulfur dioxide, and one or more sulfur-containing gases of hydrogen sulfide and carbonyl sulfide are generated. Part of the reducing gas is returned to the gasification reaction of the carbon-based material to promote the hydrolysis of the carbon-based material, and the rest is introduced with water vapor to hydrolyze the carbonyl sulfide generated by the reduction of sulfur dioxide, so that all sulfides exist in the form of hydrogen sulfide, and reducing gas is obtained. The reducing gas includes hydrogen sulfide, carbon dioxide, and water vapor;

[0065] The reduction section 3 uses a fixed bed reactor with an inner diameter of 300 mm and a length of 1.5 m;

[0066] The catalyst for the reduction reaction is 100g of a composite catalyst of cobalt (Co) and molybdenum (Mo) sulfides with a particle size of 7±1mm. The catalyst carrier is alumina (Al2O3), and the loading amounts of cobalt and molybdenum are 3% and 10% respectively. The volume of sulfur dioxide in the reduction raw gas is 33% of the sum of carbon monoxide and hydrogen in the gasification gas. Sulfur dioxide can just react completely with carbon monoxide and hydrogen. The volume ratio of hydrogen sulfide to carbon dioxide in the reduction gas is 2:3, and the volume of water vapor is 6%;

[0067] The composition of the reduction feed gas is pure sulfur dioxide, and the space velocity is 2000 mL / (min·kg);

[0068] The volume ratio of water vapor to sulfur dioxide introduced is 1:1. Water vapor hydrolyzes carbonyl sulfide produced by the reduction of sulfur dioxide, so that all sulfur-containing gases exist in the form of hydrogen sulfide.

[0069] The temperature of the reduction reaction is 450°C;

[0070] S3, in the reaction section 4, the remaining reducing gas is introduced, and the reducing raw gas containing sulfur dioxide is introduced to carry out Claus reaction, sulfur dioxide and hydrogen sulfide quickly undergo low-temperature Claus reaction to generate sulfur, and obtain product gas, which includes sulfur vapor, carbon dioxide, and water vapor;

[0071] The reaction section 4 uses a fixed bed reactor with an inner diameter of 300 mm and a length of 1 m;

[0072] The catalyst for the Claus reaction is 100g of activated alumina with a particle size of 7±1mm. The volume of sulfur dioxide in the reducing raw gas is 50% of the hydrogen sulfide in the reducing gas, so that sulfur dioxide and hydrogen sulfide react completely. The volume ratio of sulfur vapor to carbon dioxide in the product gas is 1:2, and the volume of water vapor is 18%;

[0073] The composition of the reduction feed gas is pure sulfur dioxide, and the space velocity is 1000 mL / (min·kg);

[0074] The temperature of the Claus reaction is 250°C;

[0075] S4. In the sulfur cooling unit 5, the product gas is cooled, and the sulfur vapor in the product gas is condensed into liquid and recovered in the sulfur recovery unit 7. In the carbon dioxide cooling unit 6, the remaining carbon dioxide and water vapor are cooled again, and the water vapor is condensed into liquid. Part of the carbon dioxide is returned to the gasification reaction of the carbon-based material to participate in the gasification reaction, and the rest is recovered and processed in the carbon dioxide recovery unit 8.

[0076] In Example 1, the sulfur-containing components are all converted into hydrogen sulfide through a hydrolysis reaction and enter the Claus process, and then converted into a solid sulfur product with a purity of >99%, and the carbon element in the carbonyl sulfide is also converted into carbon dioxide through a hydrolysis reaction and recovered, thereby obtaining carbon dioxide with a purity of >99.9%. Example 1 utilizes the promoting effect of the sulfur-containing gas carbonyl sulfide / hydrogen sulfide on the carbon dioxide gasification process of the carbon-based material, while introducing a hydrolysis process to convert the carbonyl sulfide generated in the gasification process into hydrogen sulfide and carbon dioxide, thereby achieving efficient separation of sulfur resources and carbon resources.

[0077] Embodiment 2:

[0078] A method for promoting gasification of carbon-based materials and reduction of sulfur dioxide to produce sulfur is basically the same as Example 1, except that the length of the reactor of the gasification section 1 in step S1 is 2.5 m;

[0079] The carbon-based raw material is 1000 g of biomass corn stalks with a particle size of 4±1 mm. In addition to the gasification process of the carbon-based material, step S1 also includes a pyrolysis process of the biomass. The volume proportions of carbon monoxide, hydrogen and carbon dioxide in the gasification gas are 50%, 15% and 5% respectively.

[0080] The space velocity of the returned recycled gas is 1000 mL / (min·kg);

[0081] The temperature of the gasification reaction is 800°C;

[0082] The mass of the catalyst for the reduction reaction in step S2 is 60 g;

[0083] The length of the reaction section 4 in step S3 is 0.8 m;

[0084] Solid sulfur products with a purity of >99% and carbon dioxide with a purity of >99.9% were successfully recovered in Example 2. Example 2 also utilized the promotion effect of sulfur-containing gas on the carbon dioxide gasification process of carbon-based materials to achieve efficient gasification of biomass, and utilized the autocatalytic effect of hydrogen sulfide and carbonyl sulfide on sulfur dioxide reduction to achieve the coupling of biomass conversion and sulfur resource recovery.

[0085] Embodiment 3:

[0086] A method for promoting the gasification of carbon-based materials and reducing sulfur dioxide to produce sulfur is basically the same as Example 1, except that in step S1, the gasified raw gas also includes water vapor as an auxiliary agent, the volume of the auxiliary agent in the gasified raw gas is 15% of the carbon dioxide, and the carbon-based materials are co-gasified by water vapor and carbon dioxide to produce hydrogen;

[0087] The volume proportions of carbon monoxide, hydrogen, carbon dioxide and hydrogen sulfide in the gasification gas are 60%, 5%, 6% and 6% respectively.

[0088] In Example 3, solid sulfur products with a purity of >99% and carbon dioxide with a purity of >99.9% were successfully recovered. Example 3 also utilized the promotion effect of sulfur-containing gas on the carbon dioxide / water vapor co-gasification process of carbon-based materials to achieve efficient gasification of coke, and utilized the hydrolysis and hydrogenation of carbonyl sulfide by water vapor and hydrogen to convert it into hydrogen sulfide, which entered the Claus process, achieving the coupling of coke utilization and sulfur resource recovery.

[0089] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A method for producing sulfur by promoting the gasification of carbon-based materials and reducing sulfur dioxide, characterized in that: The method comprises the following steps: S1. Add carbon-based materials, introduce gasification raw gas or recycled gas containing carbon dioxide, introduce reduction raw gas containing sulfur dioxide or reduction gas containing carbonyl sulfide and hydrogen sulfide, and perform gasification reaction of carbon-based materials to obtain gasified gas, wherein hydrocarbons in the carbon-based materials exist in the form of carbon monoxide and hydrogen in the gasified gas, and sulfur in the gasified gas exists in the form of hydrogen sulfide or carbonyl sulfide; S2, introducing gasification gas, introducing reducing raw gas containing sulfur dioxide, carrying out reduction reaction of sulfur dioxide, generating one or more sulfur-containing gases of hydrogen sulfide and carbonyl sulfide, returning part of the reducing gas to the gasification reaction of the carbon-based material to promote the hydrolysis of the carbon-based material, and introducing the rest of the reducing gas into water vapor to hydrolyze the carbonyl sulfide generated by the reduction of sulfur dioxide, so that all sulfides exist in the form of hydrogen sulfide, and obtaining reducing gas, which includes hydrogen sulfide, carbon dioxide, and water vapor; S3, introducing the remaining reducing gas, introducing the reducing raw gas containing sulfur dioxide, carrying out Claus reaction, and obtaining product gas, which includes sulfur vapor, carbon dioxide, and water vapor; S4. The product gas is cooled, and the sulfur vapor in the product gas is condensed into liquid for recovery. The remaining carbon dioxide and water vapor are cooled again, and the water vapor is condensed into liquid. Part of the carbon dioxide is returned to the gasification reaction of the carbon-based material to participate in the gasification reaction, and the rest is recovered for treatment.

2. A method for producing sulfur by promoting gasification of carbon-based materials and reduction of sulfur dioxide according to claim 1, characterized in that: In step S1, the carbon-based raw material is selected from one or more of coal, lignite, coke, and biomass. The volume of the reducing raw gas or the sulfur-containing gas in the reducing gas is 1-10% of the carbon dioxide in the gasification raw gas or the recovered gas, and the sum of the volume proportions of carbon monoxide and hydrogen in the gasification gas is greater than 50%.

3. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: In step S1, the gasified raw gas further includes one or more auxiliary agents such as oxygen and water vapor, and the volume of the auxiliary agent in the gasified raw gas is 5-20% of the carbon dioxide.

4. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The temperature of the gasification reaction in step S1 is 700-950°C.

5. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The catalyst for the reduction reaction in step S2 is selected from sulfides of one or more metals selected from cobalt, molybdenum and tungsten, and the volume of sulfur dioxide in the reduction raw gas is 33% of the sum of carbon monoxide and hydrogen in the gasification gas.

6. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The volume ratio of water vapor to sulfur dioxide introduced in step S2 is (1-1.2):

1.

7. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The temperature of the reduction reaction in step S2 is 400-500°C.

8. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The catalyst for the Claus reaction in step S3 is an aluminum-based catalytic material modified with a cobalt or molybdenum active component, and the volume of sulfur dioxide in the reducing raw gas is 50% of the hydrogen sulfide in the reducing gas.

9. The method for producing sulfur by promoting gasification of carbon-based materials and reducing sulfur dioxide according to claim 1, characterized in that: The temperature of the Claus reaction in step S3 is 250-400°C.

10. A device for promoting the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur, characterized in that: The device implements the method according to any one of claims 1 to 9 to promote the gasification of carbon-based materials and the reduction of sulfur dioxide to produce sulfur. The device comprises a gasification section (1), a reduction section (3) and a reaction section (4) which are connected in sequence. A gasification gas cooling unit (2) is arranged between the gasification section (1) and the reduction section (3). A sulfur cooling unit (5) and a carbon dioxide cooling unit (6) are arranged in sequence after the reaction section (4). The reduction section (3) is connected to the regasification section (1). The carbon dioxide cooling unit (6) is connected to the regasification section (1). In the gasification section (1), carbon-based materials, carbon dioxide, and sulfur dioxide or its reduction product hydrogen sulfide or carbonyl sulfide are mixed to perform a gasification reaction of the carbon-based materials to obtain gasification gas containing carbon monoxide, hydrogen, hydrogen sulfide, carbonyl sulfide, and carbon dioxide. The gasification gas cooling unit (2) cools the gasification gas. In the reduction section (3), the gasification gas and sulfur dioxide are mixed to carry out a reduction reaction of the sulfur dioxide to obtain a reduction gas, part of which is returned to the gasification section (1) and the rest is sent to the reaction section (4). In the reaction section (4), the reducing gas and sulfur dioxide are mixed to undergo a Claus reaction to obtain a product gas. In the sulfur cooling unit (5), the product gas is cooled to separate sulfur vapor from carbon dioxide and water vapor, and sulfur is recovered. In the carbon dioxide cooling unit (6), carbon dioxide and water vapor are cooled to separate carbon dioxide and water vapor, and part of the carbon dioxide is returned to the gasification section (1), and the rest is recovered for treatment.

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