Sulfur tolerant shift process and system for organic solid waste gasified synthesis gas

Abstract

The invention discloses a sulfur-tolerant shift method and a sulfur-tolerant shift system for organic solid waste gasified synthesis gas. The method comprises the following steps: pretreating organic solid waste; the method comprises the following steps: conveying organic solid waste into a fixed bed gasifier, and carrying out gasification reaction under the action of a gasifying agent to obtain sulfur-containing synthesis gas; sulfur-containing synthesis gas is sequentially and circularly introduced into the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor for catalyst circulating vulcanization; the method comprises the following steps: pumping sulfur-containing synthesis gas by adopting a high-pressure steam pumping device, boosting to obtain raw material gas, sequentially conveying the raw material gas into a first sulfur-tolerant shift reactor and a second sulfur-tolerant shift reactor, and respectively carrying out shift reaction. According to the method disclosed by the invention, the stability of the sulfur content of the synthesis gas is ensured by co-processing the organic solid wastes with different sulfur contents, and the sulfur-tolerant shift catalyst keeps high activity; and meanwhile, the sulfur-containing synthesis gas is circulated to sulfurize the catalyst and the tar is converted in the furnace, so that pre-sulfurization and gas purification cooling sections outside the reactor are avoided, and direct high-temperature conversion hydrogen production of the synthesis gas is realized.

Description

Technical Field

[0001] The present application belongs to the technical field of sulfur-resistant conversion of synthesis gas, and specifically relates to a sulfur-resistant conversion method and system for converting organic solid waste into synthesis gas. Background Art

[0002] With the rapid development of industrialization, urbanization and economy, the treatment of solid waste is a problem faced by most countries in the world. Improper disposal will lead to huge health and environmental burdens. Different types of solid waste can be divided into industrial, agricultural, sanitary and municipal waste according to their sources. At the same time, these wastes are rich in organic matter and have high application potential. Due to the depletion of fossil fuels and their negative impact on the environment, people generally need clean and affordable energy, which has also promoted the transition to renewable energy, thereby providing reliable, cost-effective and carbon-neutral energy. Thermal conversion technology can convert organic solid waste into products with resource characteristics and can also dispose of waste safely and effectively. Among them, gasification technology is carried out under a certain atmosphere, generally air, O2, CO2, steam, etc., which can convert organic solid waste into synthesis gas, and has been widely studied and applied in industry. With the increasing interest in clean technology and renewable energy, hydrogen has become a promising energy carrier. Gasification synthesis gas is therefore used as a raw gas to produce hydrogen through the water-gas shift reaction.

[0003] At present, the synthesis gas water gas shift reaction can be mainly divided into three major catalytic processes according to the type of catalyst: iron-chromium based, copper based, and cobalt-molybdenum based. The synthesis gas produced by waste gasification contains trace amounts of sulfur, which can cause rapid deactivation of the catalyst. In this case, sulfur poisoning is one of the main issues related to the industrial application of the water gas shift reaction, and the development of sulfur-resistant catalysts has become a relevant issue. Cobalt-molybdenum based catalysts are good sulfur-resistant wide-temperature shift catalysts and can be used for the water gas shift reaction of sour gas. However, the activity of these catalysts depends on the concentration of sulfur in the feed and the concentration of sulfur in the sulfidation source. Cobalt-molybdenum based catalysts can only maintain a high water gas shift activity when they are in a sulfided state.

[0004] However, the composition of organic solid waste varies, and the gasification characteristics are also very different. Existing technologies mainly focus on the energy conversion potential of specific types of organic solid waste, which is not conducive to the comprehensive treatment and transformation of organic solid waste, and cannot guarantee the sulfur concentration of synthesis gas. At the same time, the tar content of organic solid waste gasification is high, and the decoking and purification process is required, which leads to additional energy consumption and process costs.

[0005] From this point of view, the existing technology has always been the key problem that plagues the industrial expansion of organic solid waste gasification and hydrogen production, including the sulfur-resistant conversion process of organic solid waste synthesis gas with poor uniformity, the unstable composition of the synthesis gas, and the reduced activity of the sulfur-resistant conversion catalyst caused by changes in the sulfur content. Summary of the invention

[0006] The present application aims to solve one of the technical problems in the related art at least to a certain extent. To this end, the purpose of the present application is to propose a sulfur-resistant conversion method and system for organic solid waste gasification synthesis gas.

[0007] In one aspect of the present application, the present application proposes a sulfur-resistant conversion method for organic solid waste gasification synthesis gas. According to an embodiment of the present application, the method includes:

[0008] (1) Pretreatment of organic solid waste;

[0009] (2) transporting the organic solid waste to a fixed bed gasifier, performing a gasification reaction under the action of a gasifying agent, and obtaining sulfur-containing synthesis gas;

[0010] (3) circulating the sulfur-containing synthesis gas into a first sulfur-tolerant shift reactor and a second sulfur-tolerant shift reactor in sequence to perform catalyst circulation sulfurization, and when the sulfur content of the synthesis gas after the catalyst circulation sulfurization is stable, the catalyst circulation sulfurization is terminated, and the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor are respectively provided with catalysts;

[0011] (4) A high-pressure steam extractor is used to extract the sulfur-containing synthesis gas and increase its pressure to obtain a raw gas, and the raw gas is sequentially transported to the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor to perform shift reactions respectively.

[0012] According to the sulfur-resistant conversion method for organic solid waste gasification synthesis gas of the embodiment of the present application, first, compared with the traditional process, the method of the present application is more in line with the source characteristics of organic solid waste synthesis gas, and reduces the formation of tar and improves the process efficiency, avoiding the synthesis gas cooling and purification section. Second, compared with the commonly used sulfur-resistant conversion process, the method of the present application synergistically disposes of a variety of organic solid wastes to produce synthesis gas with stable sulfur content, and uses sulfur-containing synthesis gas to achieve catalyst circulation sulfurization, avoiding additional pre-sulfurization process and equipment investment. Third, compared with the multi-stage low-temperature conversion process, the method of the present application directly produces hydrogen through high-temperature conversion, avoiding the energy loss of multiple heating and cooling, reducing the cost of preparing hot air and water vapor, and the comprehensive utilization efficiency of heat is high.

[0013] In addition, the sulfur-resistant conversion method for converting organic solid waste into synthesis gas according to the above embodiment of the present application may also have the following additional technical features:

[0014] In some embodiments of the present application, between step (1) and step (2), the following further comprises: (1-5) high-pressure thermoforming of the pretreated organic solid waste to prepare homogeneous formed particles.

[0015] In some embodiments of the present application, in step (1), the organic solid waste includes a first organic solid waste and a second organic solid waste, the sulfur content of the first organic solid waste is lower than the sulfur content of the second organic solid waste; the first organic solid waste includes agricultural and forestry biomass, and the second organic solid waste includes at least one of waste automobile tires, municipal garbage, industrial solid waste, and sludge.

[0016] In some embodiments of the present application, in step (2), the volume content of oxygen in the gasifying agent is 30% to 50%; and / or, in step (2), the tar content in the sulfur-containing synthesis gas is less than 500 mg / m 3 ; and / or, in step (2), the sulfur content in the sulfur-containing synthesis gas is 300ppm~1300ppm; and / or, in step (2), the temperature of the sulfur-containing synthesis gas is 450℃~650℃.

[0017] In some embodiments of the present application, in step (3), the catalyst has Al2O3-MgO-TiO2 as a carrier, Co-Mo as an active component, and CeO2 as an active additive; and / or, in step (3), the temperatures in the first sulfur-resistant shift reactor and the second sulfur-resistant shift reactor are 300°C to 600°C, respectively.

[0018] In some embodiments of the present application, taking the total content of the catalyst as 100%, the CoO content in the catalyst is 2.0% to 5.0%, the MoO3 content in the catalyst is 5.0% to 10.0%, the MgO content in the catalyst is 10.0% to 20.0%, the Al2O3 content in the catalyst is 30.0% to 40.0%, the TiO2 content in the catalyst is 15.0% to 20.0%, and the CeO2 content in the catalyst is 10.0% to 15.0%.

[0019] In some embodiments of the present application, in step (4), the steam-to-gas ratio of the raw gas is 1.0-2.0, and the pressure is 4.0 MPa-7.0 MPa; and / or, in step (4), the temperature of the shift reaction in the first sulfur-resistant shift reactor is 500°C-600°C, and the temperature of the shift reaction in the second sulfur-resistant shift reactor is 300°C-400°C.

[0020] In some embodiments of the present application, the above method further includes: (5) desulfurizing and decarbonizing the gas obtained by the conversion reaction in step (4).

[0021] In a second aspect of the present application, the present application proposes a system for implementing the sulfur-resistant conversion method for organic solid waste gasification synthesis gas described in the above embodiment. According to the embodiment of the present application, the system includes:

[0022] Organic solid waste pretreatment system;

[0023] A high-pressure molding machine, wherein the feed port of the high-pressure molding machine is connected to the discharge port of the organic solid waste pretreatment system;

[0024] A fixed bed gasifier, wherein the feed port of the fixed bed gasifier is connected to the discharge port of the high pressure molding machine;

[0025] a first sulfur-resistant shift reactor, wherein an air inlet of the first sulfur-resistant shift reactor is connected to a gas outlet of the fixed bed gasifier;

[0026] a second sour-resistant shift reactor, wherein an air inlet of the second sour-resistant shift reactor is connected to an air outlet of the first sour-resistant shift reactor;

[0027] a first high-pressure steam extractor, the first high-pressure steam extractor being disposed between the fixed-bed gasifier and the first sour-resistant shift reactor;

[0028] A second high-pressure steam extractor is disposed between the first sour-tolerant shift reactor and the second sour-tolerant shift reactor.

[0029] According to the system of the embodiment of the present application, various organic solid wastes can be synergistically treated to produce synthesis gas with stable sulfur content, and the sulfur-containing synthesis gas can be used to realize catalyst circulation sulfurization, avoiding additional pre-sulfurization process and equipment investment. At the same time, the system of the present application can directly produce hydrogen by high-temperature conversion, avoiding the energy loss of multiple heating and cooling, reducing the cost of preparing hot air and water vapor, and has the characteristics of simple design and low investment, and has good economic benefits and application prospects.

[0030] In addition, the system according to the above embodiment of the present application may also have the following additional technical features:

[0031] In some embodiments of the present application, stop valves are respectively provided between the first high-pressure steam extractor and the first sulfur-resistant conversion reactor, between the second high-pressure steam extractor and the second sulfur-resistant conversion reactor, and between the first sulfur-resistant conversion reactor and the second sulfur-resistant conversion reactor; and / or, the above-mentioned system also includes: a desulfurization and decarbonization tower, the air inlet of the desulfurization and decarbonization tower is connected to the air outlet of the second sulfur-resistant conversion reactor.

[0032] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0034] Figure 1 This is a schematic flow diagram of the sulfur-resistant conversion method for converting organic solid waste into synthesis gas in the present application;

[0035] Figure 2 This is a schematic diagram of the structure of the sulfur-resistant conversion system for converting organic solid waste gas into synthesis gas in the present application.

[0036] Reference numerals:

[0037] Among them, 1-organic solid waste pretreatment system, 2-high pressure molding machine, 3-fixed bed gasification furnace, 4-first high-pressure steam extractor, 5-first sulfur-resistant shift reactor, 6-second high-pressure steam extractor, 7-second sulfur-resistant shift reactor, 8-first stop valve, 9-second stop valve, 10-third stop valve, 11-fourth stop valve, 12-fifth stop valve, 13-desulfurization and decarbonization tower. DETAILED DESCRIPTION

[0038] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0039] In one aspect of the present application, the present application proposes a sulfur-resistant conversion method for organic solid waste gasification synthesis gas. According to the embodiments of the present application, referring to the attached Figure 1 The method includes: S100: pre-treating organic solid waste; S200: transporting the organic solid waste to a fixed bed gasifier, performing a gasification reaction under the action of a gasifying agent, and obtaining a sulfur-containing synthesis gas; S300: circulating the sulfur-containing synthesis gas into a first sulfur-resistant shift reactor and a second sulfur-resistant shift reactor in sequence, and performing a catalyst circulation sulfurization. When the sulfur content of the synthesis gas after the catalyst circulation sulfurization is stable, the catalyst circulation sulfurization is terminated, and the first sulfur-resistant shift reactor and the second sulfur-resistant shift reactor are respectively provided with catalysts; S400: using an extractor to extract the sulfur-containing synthesis gas and increase the pressure to obtain a raw gas, and transporting the raw gas to the first sulfur-resistant shift reactor and the second sulfur-resistant shift reactor in sequence, and performing a conversion reaction respectively. Therefore, the method of the present application realizes the coordinated disposal of organic solid waste. By co-disposing of organic solid waste with different sulfur contents, the sulfur content of the synthesis gas is ensured to be stable, and the sulfur-resistant conversion catalyst is kept highly active. At the same time, the sulfur-containing synthesis gas circulating sulfurization catalyst and the conversion in the tar furnace avoid the pre-sulfurization and gas purification and cooling sections outside the reactor, realize the direct high-temperature conversion of the synthesis gas to produce hydrogen, reduce the process cost, and have good economic benefits and application prospects.

[0040] The sulfur-resistant conversion method for organic solid waste gasification synthesis gas proposed in this application is described in detail below:

[0041] Specifically, refer to the attached Figure 1 The above-mentioned sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas comprises the following steps:

[0042] S100: pre-treatment of organic solid waste;

[0043] In this step, the organic solid waste first enters the coarse crusher to be roughly crushed into large particles with a particle size of less than 10 cm, and then the non-combustibles and combustibles are separated by magnetic separation, screening, wind separation and other sorting equipment. Then the combustibles enter the fine crusher for secondary crushing to obtain small particles with a particle size of less than 1 cm, and the organic solid wastes with different sulfur contents (two or more) are evenly mixed and then enter the dryer to reduce the moisture content to less than 10%.

[0044] According to some specific embodiments of the present application, the above-mentioned organic solid waste includes a first organic solid waste and a second organic solid waste, and the sulfur content of the first organic solid waste is lower than the sulfur content of the second organic solid waste; the first organic solid waste includes agricultural and forestry biomass (low-sulfur organic solid waste), and the second organic solid waste includes at least one of waste automobile tires, municipal garbage, industrial solid waste, and sludge.

[0045] According to some specific embodiments of the present application, the following may be further included between step S100 and step S200:

[0046] S150: performing high-pressure thermoforming on the pretreated organic solid waste to prepare homogeneous formed particles;

[0047] Specifically, the dried organic solid waste is fed into a screw extrusion high pressure molding machine 2 and compressed into 1 t / m 3 High-density molded fuel of about 10000 tons; the discharged material obtains homogeneous molded particles with a particle size of 40mm to 60mm. The molded particles are dry columns with stable sulfur content and are then naturally cooled and stored.

[0048] S200: transporting the organic solid waste to a fixed bed gasifier, and performing a gasification reaction under the action of a gasifying agent to obtain sulfur-containing synthesis gas;

[0049] In this step, a feeding system is arranged above the fixed bed gasifier 3, and the above-mentioned molded particles are transported into the feeding system. Control valves are respectively arranged at the top and bottom of the feeding system, and the bottom control valve is closed; then the top and bottom air inlets of the fixed bed gasifier 3 are opened, and the gasifying agent is introduced into the furnace to exhaust the air; then the top valve of the feeding system is closed, and the bottom control valve of the feeding system is opened to start feeding; finally, the gasifier is ignited, and the feeding is continuously controlled to reach a gasification temperature of 800°C to 900°C, and the molded particles are oxygen-enriched and gasified to obtain sulfur-containing synthesis gas, and ash is intermittently discharged from the bottom of the gasifier.

[0050] The fixed bed gasifier 3 may be provided with a double oxidation layer and adopt an oxygen-rich gasifying agent to realize the conversion of tar in the furnace and obtain a high-temperature, low-tar, sulfur-containing synthesis gas.

[0051] According to some further specific embodiments of the present application, the volume content of oxygen in the gasifying agent is 30% to 50%, and as an example, it can be 30%, 35%, 40%, 45%, 50%, etc., thereby further ensuring the conversion in the tar furnace to obtain a high-temperature low-tar sulfur-containing synthesis gas, so that the tar content in the sulfur-containing synthesis gas is less than 500 mg / m 3 , and at the same time, the sulfur content in the sulfur-containing synthesis gas is 300ppm~1300ppm.

[0052] According to some further specific embodiments of the present application, the temperature of the sulfur-containing synthesis gas at the outlet of the fixed bed gasifier may be 450°C to 650°C, preferably 500°C to 600°C.

[0053] S300: circulating the sulfur-containing synthesis gas into the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor in sequence to perform catalyst circulation sulfurization;

[0054] In this step, the above-mentioned sulfur-containing synthesis gas is circulated into the first sulfur-resistant conversion reactor 5 and the second sulfur-resistant conversion reactor 7 in sequence to carry out catalyst circulation sulfidation. When the sulfur content of the synthesis gas after the catalyst circulation sulfidation is stable, the catalyst circulation sulfidation is completed. The first sulfur-resistant conversion reactor 5 and the second sulfur-resistant conversion reactor 7 are respectively provided with catalysts.

[0055] Reference Figure 2, open the first stop valve 8, the second stop valve 9 and the fourth stop valve 11, close the third stop valve 10 and the fifth stop valve 12, and circulate the above-mentioned sulfur-containing synthesis gas into the catalyst bed in the first sulfur-resistant shift reactor 5 and the second sulfur-resistant shift reactor 7 in sequence; the sulfur-containing synthesis gas flows through the catalyst bed to promote the catalyst to heat up, and after a uniform heating process, the temperature balance of each point of the catalyst bed is maintained, and the outlet temperature of the sulfur-containing synthesis gas at the sulfur-resistant shift reactor is maintained to be not less than 300°C. As the catalyst bed temperature gradually increases, the catalyst in the shift reactor undergoes a sulfurization reaction, and the catalyst is gradually activated; the hydrogen sulfide concentration of the sulfur-containing synthesis gas at the outlet of the shift reactor is detected every 60 minutes. When the hydrogen sulfide content of the sulfur-containing synthesis gas at the outlet of the shift reactor is greater than 300ppm, the catalyst bed of the shift reactor enters the sulfurization period; at this time, the active components of the catalyst are sulfurized: CoO+H2S→H2O+CoS, MoO3+H2+2H2S→3H2O+MoS2. Then open the third stop valve 10 appropriately and adjust its opening to keep the catalyst bed temperature no higher than 600°C. When the hydrogen sulfide content of the sulfur-containing synthesis gas at the outlet of the conversion reactor is greater than 300 ppm and lasts for more than 8 hours, that is, when the sulfur content of the outlet gas at the third stop valve 10 is continuously consistent, the catalyst bed sulfurization period ends and the synthesis gas high-temperature sulfur-resistant conversion reaction stage can be entered.

[0056] According to some other specific embodiments of the present application, the above-mentioned catalyst uses Al2O3-MgO-TiO2 as a carrier, Co-Mo as an active component, and CeO2 as an active additive. Specifically, taking the total content of the catalyst as 100%, the CoO content in the catalyst is 2.0%~5.0%, the MoO3 content in the catalyst is 5.0%~10.0%, the MgO content in the catalyst is 10.0%~20.0%, the Al2O3 content in the catalyst is 30.0%~40.0%, the TiO2 content in the catalyst is 15.0%~20.0%, and the CeO2 content in the catalyst is 10.0%~15.0%.

[0057] According to some other specific embodiments of the present application, the catalyst is in the shape of strips or columns, and its average particle size is 2 mm to 5 mm.

[0058] According to some further specific embodiments of the present application, in step S300, the temperatures in the first sulfur-resistant shift reactor and the second sulfur-resistant shift reactor are respectively 300° C. to 600° C., thereby further ensuring the smooth progress of the catalyst sulfurization reaction.

[0059] S400: A high-pressure steam extractor is used to extract the sulfur-containing synthesis gas and increase its pressure to obtain a raw gas, and the raw gas is sequentially transported to a first sulfur-tolerant shift reactor and a second sulfur-tolerant shift reactor to perform shift reactions respectively.

[0060] Reference Figure 2 , close the first stop valve 8, the second stop valve 9 and the fourth stop valve 11, open the third stop valve 10 and the fifth stop valve 12, start the first high-pressure steam extractor 4 to extract the above-mentioned sulfur-containing synthesis gas and increase the pressure to add water vapor to obtain raw gas, control the steam-gas ratio of the raw gas, and send the raw gas to the first sulfur-resistant shift reactor 5 for high-temperature rough shift reaction; then start the second high-pressure steam extractor 6 to extract the conversion gas obtained by the reaction of the first sulfur-resistant shift reactor 5 and increase the pressure, and enter the second sulfur-resistant shift reactor 7 for medium-temperature fine shift reaction, and the conversion reaction is: CO+water vapor→H2+CO2. The outlet gas of the second sulfur-resistant shift reactor 7 is a rough product gas, in which the CO content is less than 1.0%.

[0061] According to some other specific embodiments of the present application, the steam-to-gas ratio (volume ratio) of the above-mentioned raw gas is 1.0-2.0, preferably 1.6-2.0, and the pressure is 4.0MPa-7.0MPa, preferably 4.0MPa-6.0MPa, thereby further ensuring the full progress of the conversion reaction, further reducing the CO concentration and increasing the hydrogen concentration.

[0062] According to some other specific embodiments of the present application, the temperature of the shift reaction in the first sulfur-resistant shift reactor is 500°C to 600°C, and the temperature of the shift reaction in the second sulfur-resistant shift reactor is 300°C to 400°C, so as to further reduce the CO concentration and increase the hydrogen concentration.

[0063] The above method further includes:

[0064] S500: Desulfurizing and decarbonizing the raw product gas obtained by the shift reaction in step S400.

[0065] In this step, the crude product gas is air-cooled and then enters the desulfurization and decarbonization tower 13, where it is washed with methanol solution to remove carbon dioxide and sulfur-containing gases to obtain crude hydrogen, wherein the H2S content of the crude hydrogen is reduced to below 0.1ppm, the CO2 content is less than 20ppm, and the hydrogen content is higher than 90.0%.

[0066] The sulfur-resistant conversion method for converting organic solid waste into synthesis gas according to the embodiment of the present application has at least one of the following advantages:

[0067] First, compared with the traditional process, the method of the present application is more in line with the source characteristics of organic solid waste synthesis gas, reduces the formation of tar and improves process efficiency, and avoids the synthesis gas cooling and purification stage.

[0068] Second, compared with the commonly used sulfur-resistant conversion process, the method of the present application synergistically treats a variety of organic solid wastes to produce synthesis gas with stable sulfur content, and utilizes the sulfur-containing synthesis gas to achieve catalyst circulation sulfurization, avoiding additional pre-sulfurization process and equipment investment.

[0069] Third, compared with the multi-stage low-temperature conversion process, the method of the present application directly produces hydrogen through high-temperature conversion, which avoids the energy loss of multiple heating and cooling processes, reduces the cost of preparing hot air and water vapor, and has a high comprehensive utilization efficiency of heat.

[0070] In the second aspect of the present application, the present application proposes a system for implementing the above embodiment method. According to the embodiment of the present application, referring to the attached Figure 2 The system includes: an organic solid waste pretreatment system 1; a high pressure molding machine 2, the feed port of the high pressure molding machine 2 is connected to the discharge port of the organic solid waste pretreatment system 1; a fixed bed gasifier 3, the feed port of the fixed bed gasifier 3 is connected to the discharge port of the high pressure molding machine 2; a first sulfur-resistant shift reactor 5, the air inlet of the first sulfur-resistant shift reactor 5 is connected to the air outlet of the fixed bed gasifier 3; a second sulfur-resistant shift reactor 7, the air inlet of the second sulfur-resistant shift reactor 7 is connected to the air outlet of the first sulfur-resistant shift reactor 5; a first high-pressure steam extractor 4, the first high-pressure steam extractor 4 is arranged between the fixed bed gasifier 3 and the first sulfur-resistant shift reactor 5; a second high-pressure steam extractor 6, the second high-pressure steam extractor 6 is arranged between the first sulfur-resistant shift reactor 5 and the second sulfur-resistant shift reactor 7. Therefore, the system of the present application can synergistically treat a variety of organic solid wastes to produce synthesis gas with stable sulfur content, use sulfur-containing synthesis gas to achieve catalyst circulation sulfurization, and avoid additional presulfurization process and equipment investment. At the same time, the system of the present application can directly produce hydrogen through high-temperature conversion, avoiding energy loss from multiple heating and cooling, reducing the cost of preparing hot air and water vapor, and has the characteristics of simple design and low investment, and has good economic benefits and application prospects.

[0071] In an embodiment of the present application, the above-mentioned organic solid waste pretreatment system 1 is used to pretreat organic solid waste. The organic solid waste first enters the coarse crusher to be coarsely crushed into large particles with a particle size of less than 10 cm, and the non-combustibles and combustibles are separated by magnetic separation, screening, air separation and other sorting equipment. Then the combustibles enter the fine crusher for secondary crushing to obtain small particles with a particle size of less than 1 cm, and the organic solid wastes with different sulfur contents (two or more) are evenly mixed and then enter the dryer to reduce the moisture content to less than 10%. The above-mentioned high-pressure molding machine 2 is used to perform high-pressure hot molding on the pretreated organic solid waste to prepare homogeneous molded particles. The above-mentioned fixed bed gasifier 3 is used to gasify the organic solid waste under the action of a gasifying agent to obtain sulfur-containing synthesis gas.

[0072] In an embodiment of the present application, catalysts are respectively provided in the above-mentioned first sulfur-tolerant conversion reactor 5 and the second sulfur-tolerant conversion reactor 7. First, the sulfur-containing synthesis gas is circulated into the first sulfur-tolerant conversion reactor 5 and the second sulfur-tolerant conversion reactor 7 in sequence to carry out catalyst circulation sulfurization. That is, when the sulfur content of the sulfur-containing synthesis gas at the outlet of the conversion reactor continues to be consistent, the sulfurization period of the catalyst ends, and the synthesis gas high-temperature sulfur-tolerant conversion reaction stage can be entered to react CO and water vapor in the sulfur-containing synthesis gas to generate H2+CO2.

[0073] In the embodiment of the present application, the first high-pressure steam extractor 4 is used to extract the sulfur-containing synthesis gas and increase the pressure to obtain the raw gas, control the steam-gas ratio of the raw gas, and send the raw gas to the first sulfur-resistant shift reactor 5 for high-temperature rough shift reaction. The second high-pressure steam extractor 6 is used to extract the shift gas obtained by the reaction of the first sulfur-resistant shift reactor 5 and increase the pressure, and enter the second sulfur-resistant shift reactor 7 for medium-temperature fine shift reaction.

[0074] According to some specific embodiments of the present application, a stop valve is respectively provided between the first high-pressure steam extractor 4 and the first sulfur-resistant shift reactor 5, between the second high-pressure steam extractor 6 and the second sulfur-resistant shift reactor 7, and between the first sulfur-resistant shift reactor 5 and the second sulfur-resistant shift reactor 7. Specifically, refer to the attached Figure 2 , including a first stop valve 8, a second stop valve 9, a third stop valve 10, a fourth stop valve 11 and a fifth stop valve 12.

[0075] According to some specific embodiments of the present application, it further comprises: a desulfurization and decarbonization tower 13, the air inlet of the desulfurization and decarbonization tower 13 is connected to the air outlet of the second sulfur-resistant shift reactor 7. The above-mentioned crude product gas enters the desulfurization and decarbonization tower 13 after air cooling, and is washed with methanol solution to remove carbon dioxide and sulfur-containing gas therein to obtain crude hydrogen.

[0076] The embodiments of the present application are described in detail below. It should be noted that the embodiments described below are exemplary and are only used to explain the present application, and should not be construed as limiting the present application. In addition, unless otherwise explicitly stated, all reagents used in the following embodiments are commercially available or can be synthesized according to this article or known methods, and the reaction conditions not listed are also easily available to those skilled in the art.

[0077] Example 1

[0078] The product gas preparation process of this embodiment is as follows Figure 1 As shown, this embodiment uses microalgae and automobile crushing residue as raw materials, and the specific implementation method is described as follows.

[0079] 1) Pretreatment of organic solid waste: The microalgae and automobile crushing residue are first respectively fed into a coarse crusher to be roughly crushed into large particles less than 10 cm, and then separated from the combustibles by magnetic separation, screening, air separation and other sorting equipment; then they are respectively fed into a fine crusher for secondary crushing to obtain small particles less than 1 cm; the sulfur content of the microalgae is 0.4wt%, and the sulfur content of the automobile crushing residue is 2.0wt%; the microalgae and the automobile crushing residue are uniformly mixed in a mass ratio of 4:6, and then fed into a dryer, and the moisture content is 6.4% after drying for 8 hours.

[0080] 2) High-pressure hot forming: The dried and uniformly mixed combustibles are fed into a high-pressure screw extrusion forming machine 2, and compressed into 1 t / m at a high temperature of 200°C using solid alternative fuel preparation technology. 3 The high-density molded fuel is about 1000 g; the discharged material is homogeneous molded particles with a particle size of about 50 mm. The molded particles are dry columns with a stable sulfur content (1.36 wt%), and then naturally cooled and stored.

[0081] 3) Fixed bed oxygen-enriched gasification: The formed particles are transported in batches into the feeding system arranged above the fixed bed gasifier 3. The feeding rate is controlled by valves at the top and bottom of the feeding system. The top and bottom air inlets of the fixed bed gasifier 3 are opened, and a mixed gas gasifying agent of air and oxygen (oxygen content is 35%) is introduced into the furnace to exhaust the air; the top valve of the feeding system is closed, and the control valve at the bottom of the feeding system is opened to start feeding; the gasifier is ignited, and the formed particles begin to gasify with oxygen enrichment. The feeding is continuously controlled to reach a gasification temperature of 800°C to 900°C, and ash is intermittently discharged from the bottom of the gasifier; the fixed bed gasifier has a double oxide layer, and the above-mentioned oxygen-enriched gasifying agent (oxygen content is 35%) is used to realize the conversion in the tar furnace, and a high-temperature, low-tar sulfur-containing synthesis gas (tar content is less than 500mg / m 3 ), the syngas temperature at the gasifier outlet is about 600°C, and the sulfur content is stable at 300ppm~1000ppm.

[0082] 4) Catalyst circulation sulfurization: Open the first stop valve 8, the second stop valve 9 and the fourth stop valve 11, close the third stop valve 10 and the fifth stop valve 12, and circulate the above sulfur-containing synthesis gas into the catalyst bed in the first sulfur-resistant shift reactor and the second sulfur-resistant shift reactor in sequence. The above catalyst is in strip or column shape, with Al2O3-MgO-TiO2 as a carrier, Co-Mo as an active component, and CeO2 as an active additive, with a total content of 100%, a CoO content of 5.0%, a MoO3 content in the catalyst of 10.0%, a MgO content in the catalyst of 15.0%, an Al2O3 content in the catalyst of 40.0%, a TiO2 content in the catalyst of 15.0%, and a CeO2 content in the catalyst of 15.0%.

[0083] The sulfur-containing synthesis gas flows through the catalyst bed to cause the catalyst to heat up. After a uniform heating process, the temperature balance of each point of the catalyst bed is maintained, and the outlet temperature of the sulfur-containing synthesis gas in the sulfur-resistant shift reactor is maintained at not less than 300°C. As the catalyst bed temperature gradually increases, the catalyst in the shift reactor undergoes a sulfurization reaction, and the catalyst is gradually activated; the hydrogen sulfide concentration is detected every 60 minutes. When the hydrogen sulfide content of the outlet gas of the shift reactor is greater than 300ppm, the catalyst bed of the shift reactor enters the sulfurization period, and the active components of the catalyst are sulfurized. Then the third stop valve 10 is appropriately opened and its opening is adjusted to keep the catalyst bed temperature below 550°C. When the hydrogen sulfide content of the outlet gas is greater than 300ppm and lasts for more than 8 hours, that is, when the sulfur content of the outlet gas at the third stop valve 10 is continuously consistent, the catalyst bed sulfurization period ends and enters the synthesis gas high-temperature sulfur-resistant shift reaction stage.

[0084] 5) Synthesis gas high temperature sulfur-resistant shift: close the first stop valve 8, the second stop valve 9 and the fourth stop valve 11, open the third stop valve 10 and the fifth stop valve 12, start the first high-pressure steam extractor 4 to extract the above sulfur-containing synthesis gas and increase the pressure to obtain raw gas, control the steam-gas ratio of the raw gas (the steam-gas ratio of the raw gas is 2.0, and the pressure is 5.0MPa), and send the raw gas to the first sulfur-resistant shift reactor 5 for high-temperature rough shift reaction; then start the second high-pressure steam extractor 6 to extract the conversion gas obtained by the reaction of the first sulfur-resistant shift reactor 5 and increase the pressure (the steam-gas ratio of the raw gas is 2.0, and the pressure is 5.0MPa), and enter the second sulfur-resistant shift reactor 7 for medium-temperature fine shift reaction. The temperature of the shift reaction in the above-mentioned first sulfur-resistant shift reactor is 600°C, the temperature of the shift reaction in the second sulfur-resistant shift reactor is 360°C, and the outlet gas of the second sulfur-resistant shift reactor is a rough product gas, in which the CO content is less than 1.0%.

[0085] 6) Desulfurization and decarbonization: The crude product gas is air-cooled and then enters the desulfurization and decarbonization tower 13, where it is washed with methanol solution to remove carbon dioxide and sulfur-containing gases to obtain crude hydrogen, wherein the H2S content of the crude hydrogen is reduced to below 0.1ppm, the CO2 content is less than 10ppm, and the hydrogen content is higher than 95.0%.

[0086] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0087] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas, characterized in that: include: (1) Pretreatment of organic solid waste; (2) transporting the organic solid waste to a fixed bed gasifier to undergo a gasification reaction under the action of a gasifying agent to obtain sulfur-containing synthesis gas; (3) circulating the sulfur-containing synthesis gas into a first sulfur-tolerant shift reactor and a second sulfur-tolerant shift reactor in sequence to perform catalyst circulation sulfurization, and when the sulfur content of the synthesis gas after the catalyst circulation sulfurization is stable, the catalyst circulation sulfurization is terminated, and the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor are respectively provided with catalysts; (4) A high-pressure steam extractor is used to extract the sulfur-containing synthesis gas and increase its pressure to obtain a raw gas, and the raw gas is sequentially transported to the first sulfur-tolerant shift reactor and the second sulfur-tolerant shift reactor to perform shift reactions respectively.

2. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: The method further includes between step (1) and step (2): (1-5) The pretreated organic solid waste is subjected to high-pressure thermoforming to prepare homogeneous formed particles.

3. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: In step (1), the organic solid waste includes a first organic solid waste and a second organic solid waste, and the sulfur content of the first organic solid waste is lower than the sulfur content of the second organic solid waste; The first organic solid waste includes agricultural and forestry biomass, and the second organic solid waste includes at least one of waste automobile tires, municipal garbage, industrial solid waste, and sludge.

4. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: In step (2), the volume content of oxygen in the gasifying agent is 30% to 50%; And / or, in step (2), the tar content in the sulfur-containing synthesis gas is less than 500 mg / m 3 ; and / or, in step (2), the sulfur content in the sulfur-containing synthesis gas is 300 ppm to 1300 ppm; And / or, in step (2), the temperature of the sulfur-containing synthesis gas is 450°C to 650°C.

5. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: In step (3), the catalyst uses Al2O3-MgO-TiO2 as a carrier, Co-Mo as an active component, and CeO2 as an active additive; And / or, in step (3), the temperatures in the first sour-tolerant shift reactor and the second sour-tolerant shift reactor are respectively 300° C. to 600° C.

6. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 5, characterized in that: Taking the total content of the catalyst as 100%, the CoO content in the catalyst is 2.0% to 5.0%, the MoO3 content in the catalyst is 5.0% to 10.0%, the MgO content in the catalyst is 10.0% to 20.0%, the Al2O3 content in the catalyst is 30.0% to 40.0%, the TiO2 content in the catalyst is 15.0% to 20.0%, and the CeO2 content in the catalyst is 10.0% to 15.0%.

7. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: In step (4), the steam-gas ratio of the raw gas is 1.0-2.0, and the pressure is 4.0 MPa-7.0 MPa; And / or, in step (4), the temperature of the shift reaction in the first sulfur-tolerant shift reactor is 500°C to 600°C, and the temperature of the shift reaction in the second sulfur-tolerant shift reactor is 300°C to 400°C.

8. The sulfur-resistant conversion method for converting organic solid waste gas into synthesis gas according to claim 1, characterized in that: Also includes: (5) Desulfurizing and decarbonizing the gas obtained by the conversion reaction in step (4).

9. A system for implementing the sulfur-resistant conversion method for converting organic solid waste into synthesis gas according to any one of claims 1 to 8, characterized in that: include: Organic solid waste pretreatment system; A high-pressure molding machine, wherein the feed port of the high-pressure molding machine is connected to the discharge port of the organic solid waste pretreatment system; A fixed bed gasifier, wherein the feed port of the fixed bed gasifier is connected to the discharge port of the high pressure molding machine; a first sulfur-resistant shift reactor, wherein an air inlet of the first sulfur-resistant shift reactor is connected to a gas outlet of the fixed bed gasifier; a second sour-resistant shift reactor, wherein an air inlet of the second sour-resistant shift reactor is connected to an air outlet of the first sour-resistant shift reactor; a first high-pressure steam extractor, the first high-pressure steam extractor being disposed between the fixed-bed gasifier and the first sour-resistant shift reactor; A second high-pressure steam extractor is disposed between the first sour-tolerant shift reactor and the second sour-tolerant shift reactor.

10. The system according to claim 9, characterized in that Stop valves are respectively provided between the first high-pressure steam extractor and the first sour-resistant shift reactor, between the second high-pressure steam extractor and the second sour-resistant shift reactor, and between the first sour-resistant shift reactor and the second sour-resistant shift reactor; And / or, it also includes: a desulfurization and decarbonization tower, the air inlet of the desulfurization and decarbonization tower is connected to the air outlet of the second sulfur-resistant shift reactor.

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