System and method for coal gasification co-production of water-soluble potassium products with zero carbon emissions

Abstract

The present disclosure relates to a system and method for realizing zero carbon emission and co-production of water-soluble potassium product by coal gasification, which is provided with a gasification device, a cooling and purification acid gas separation device, a calcination device and a carbon fixation device. The gasification device is used for the coal material loaded with potassium-containing catalyst to generate a gasification reaction to generate a crude coal gas and a gasification ash. The gasification ash, the mixture material and oxygen are activated and treated in the calcination device to generate a solid material and flue gas. The cooling and purification acid gas separation device is used for cooling and separating carbon dioxide in the crude coal gas and the flue gas to obtain coal gas, carbon dioxide and salt-containing wastewater. The solid material, the salt-containing wastewater and the carbon dioxide are reacted in the carbon fixation device to generate carbonate and water-soluble potassium product, realizing carbon dioxide fixation and zero carbon emission, and the co-produced water-soluble potassium product can be used as the catalyst required for the gasification reaction of the gasification device.

Description

Technical Field

[0001] This disclosure relates to the field of coal gasification technology, and in particular to a system and method for co-producing water-soluble potassium products through coal gasification with zero carbon emissions. Background Technology

[0002] Currently, coal remains my country's most abundant fossil fuel in terms of energy reserves. The coal conversion process involves significant carbon emissions, making it crucial to explore clean and efficient ways to utilize coal and achieve low-carbon utilization of this high-carbon energy source in the coal chemical industry.

[0003] Catalytic gasification technology is an important way to utilize coal cleanly and efficiently. It uses water-soluble potassium as a catalyst to allow coal to react with a gasifying agent at relatively low temperatures under the catalytic action of the catalyst, producing high concentrations of methane. However, water-soluble potassium is currently in short supply.

[0004] Therefore, the problem to be solved in this application is how to utilize the abundant potassium feldspar and other potassium raw materials in nature to achieve zero carbon dioxide emissions in the coal gasification process, while also obtaining water-soluble potassium products as catalysts for coal gasification. Summary of the Invention

[0005] To solve the above-mentioned technical problems, or at least partially solve them, this disclosure provides a system and method for achieving zero carbon emissions from coal gasification and co-producing water-soluble potassium products.

[0006] In a first aspect, this disclosure provides a system for co-producing water-soluble potassium products through coal gasification to achieve zero carbon emissions, including a gasification unit, a cooling and purification acid gas separation unit, a roasting unit, and a carbon fixation unit. The gasification device is used to gasify coal loaded with a potassium catalyst to generate crude coal gas and gasification ash. The gasification device has a crude coal gas outlet for discharging the crude coal gas and an ash outlet for discharging the gasification ash. The roasting device has a first inlet connected to the ash outlet, a second inlet for the mixed material to enter, and a third inlet for oxygen to enter, so that the gasified ash, the mixed material, and the oxygen are activated within the roasting device to generate solid material and flue gas; the roasting device has a first outlet for the flue gas to be discharged and a second outlet for the solid material to be discharged. The cooling inlet of the cooling and purifying acid gas separation device is connected to the first outlet and the crude coal gas outlet, respectively. The cooling and purifying acid gas separation device is used to cool the crude coal gas and the flue gas and separate the carbon dioxide in the crude coal gas and the flue gas to obtain coal gas, carbon dioxide and saline wastewater. The cooling and purifying acid gas separation device has a carbon dioxide outlet for carbon dioxide discharge and a saline wastewater outlet for saline wastewater discharge. The carbon fixation device has a carbon fixation inlet that is connected to the second outlet, the saline wastewater outlet, and the carbon dioxide outlet, respectively, so that the carbon dioxide, the saline wastewater, and the solid material react in the carbon fixation device to generate carbonate and water-soluble potassium products.

[0007] According to one embodiment of this disclosure, a conversion separation device is further included, wherein the conversion inlet of the conversion separation device is connected to the cooling outlet of the cooling and purifying acid gas separation device, and the conversion separation device is used to convert the coal gas entering through the conversion inlet to form chemicals and natural gas.

[0008] According to one embodiment of the present disclosure, a solid-liquid separation device is further included, the solid-liquid separation device having a solid-liquid inlet communicating with the solid carbon outlet of the carbon fixation device, the solid-liquid separation device being used to perform solid-liquid separation on the carbonate and water-soluble potassium products entering through the solid-liquid inlet to obtain a carbonate and water-soluble potassium solution.

[0009] According to one embodiment of this disclosure, a coal preparation device is further included, the coal preparation device having a liquid inlet connected to the solid-liquid separation device and a material inlet for coal to enter, so that the water-soluble potassium solution and the coal are mixed in the coal preparation device to form the coal loaded with potassium catalyst; the coal preparation device has a coal outlet connected to the gasification device to provide the coal loaded with potassium catalyst to the gasification device.

[0010] According to one embodiment of the present disclosure, a gas-solid separation device is further included, the gas-solid separation device having a gas-solid separation inlet connected to the crude gas outlet, the gas-solid separation device being used to perform gas-solid separation on the crude gas to obtain crude gas and solid fly ash; the gas-solid separation device having a fly ash outlet for discharging the solid fly ash, the fly ash outlet being connected to the roasting device.

[0011] According to one embodiment of this disclosure, a waste heat recovery device is further included; the waste heat recovery device has a waste heat inlet connected to the gas-solid separation device and the first outlet respectively, and the waste heat recovery device is used to cool the crude coal gas and the flue gas to form crude coal gas and water vapor; the waste heat recovery device has a water vapor outlet connected to the gasification device and a crude coal gas outlet connected to the cooling and purification acid gas separation device.

[0012] According to one embodiment of this disclosure, the cooling and purification acid gas separation device includes a cooling and purification device, a cooling inlet is provided on the cooling and purification device, and the cooling inlet is connected to the crude coal gas outlet. The cooling and purification device is used to cool the crude coal gas and separate carbon dioxide from the crude coal gas to obtain cooled crude coal gas and saline wastewater. The saline wastewater outlet is provided on the cooling and purification device.

[0013] According to one embodiment of this disclosure, the cooling and purification acid gas separation device further includes an acid gas separation device connected to the cooling and purification device. The acid gas separation device is used to separate carbon dioxide from the cooled crude coal gas to obtain carbon dioxide and the coal gas. The carbon dioxide outlet is located on the acid gas separation device.

[0014] According to one embodiment of this disclosure, a grinding device is further included, the grinding device having a grinding inlet for entering potassium raw material and calcium-containing solid waste, the grinding device being used to grind the potassium raw material and the calcium-containing solid waste to form the mixture; the grinding device having a material outlet for discharging the mixture, the material outlet being connected to the second inlet.

[0015] According to one embodiment of this disclosure, a cooling and heat recovery device is further included, the cooling and heat recovery device having a recovery inlet communicating with the second outlet, the cooling and heat recovery device being used to cool the solid material entering through the recovery inlet; the cooling and heat recovery device having a recovery outlet for discharging the solid material.

[0016] According to one embodiment of this disclosure, a crushing device is further included, the crushing device having a crushing inlet communicating with the recovery outlet, the crushing device being used to crush the solid material, and the crushing device having a crushing outlet communicating with the carbon inlet.

[0017] According to one embodiment of this disclosure, the roasting apparatus further has a feed port for feeding pulverized coal into the roasting apparatus.

[0018] Secondly, this disclosure also provides a method for co-producing water-soluble potassium products using the aforementioned system for achieving zero carbon emissions through coal gasification, the method comprising: Coal loaded with a potassium catalyst is introduced into the gasification device so that the coal loaded with the potassium catalyst undergoes a gasification reaction in the gasification device to generate crude coal gas and gasification ash. The generated gasified ash, oxygen, and mixture are sent to a calcination unit for activation treatment to generate solid materials and flue gas. The generated crude coal gas and flue gas are sent to a cooling and purification acid gas separation device to separate coal gas, carbon dioxide and saline waste liquid. The solid material, the separated carbon dioxide, and the saline waste liquid are sent to a carbon fixation device for reaction to produce carbonate and water-soluble potassium products.

[0019] According to one embodiment of this disclosure, after the step of sending the generated crude coal gas and the flue gas to a cooling and purification acid gas separation device to separate coal gas, carbon dioxide, and saline waste liquid, the method further includes: The separated coal gas is sent to a conversion and separation unit for conversion to produce chemicals and natural gas.

[0020] According to one embodiment of this disclosure, after the step of sending the solid material, the separated carbon dioxide, and the saline waste liquid to a carbon fixation device for reaction to generate a mixture of carbonate and water-soluble potassium solution, the method further includes: The carbonate and water-soluble potassium solution are fed into a solid-liquid separation device for solid-liquid separation to obtain the carbonate and water-soluble potassium solution.

[0021] According to one embodiment of this disclosure, the step of sending the generated gasified ash, oxygen, and mixture to a calcination device for activation treatment to generate solid materials and flue gas includes: Potassium feldspar and calcium-containing solid waste are mixed and crushed to form a mixture. The mixture is mixed with the gasification ash and solid fly ash obtained by coal gasification reaction in the gasification device and then sent to the roasting device. Oxygen is introduced into the roasting device to activate the oxygen, the mixture, the gasified ash, and the solid fly ash within the roasting device, thereby generating the solid material and the flue gas.

[0022] According to one embodiment of this disclosure, the mass ratio of the calcium-containing solid waste to the potassium feldspar in the mixture is between 1 and 3.

[0023] According to one embodiment of this disclosure, the calcium-containing solid waste is calcium chloride, the activation temperature in the roasting device is between 700°C and 900°C, and the activation time in the roasting device is between 1 hour and 3 hours. The calcium-containing solid waste is solid waste phosphogypsum, the activation temperature is between 1000℃ and 1300℃, and the activation time is between 1.5h and 4h. The calcium-containing solid waste is calcium oxide, the activation temperature is between 150℃ and 300℃, and the activation time is between 1h and 3h.

[0024] According to one embodiment of this disclosure, prior to the step of introducing oxygen into the roasting apparatus to activate the oxygen, the mixture, the gasified ash, and the solid fly ash within the roasting apparatus, the method further includes: An additive is introduced into the calcining apparatus to combine with the potassium feldspar in the mixture; wherein the activation temperature in the calcining apparatus is between 150°C and 250°C; and the activation time in the calcining apparatus is between 1 hour and 3 hours.

[0025] According to one embodiment of this disclosure, the mass ratio of the saline wastewater to the solid material is 3:1-5:1; the partial pressure of carbon dioxide is between 2MPa and 5MPa; and the molar ratio of carbon dioxide to calcium in the solid material is between 1 and 3.

[0026] According to one embodiment of this disclosure, when the solid material, the separated carbon dioxide, and the saline waste liquid are sent to a carbon fixation device for reaction to generate carbonate and water-soluble potassium products, the carbon fixation device is stirred by a stirring device; wherein the stirring speed of the stirring device is between 200 r / min and 500 r / min, and the reaction time in the carbon fixation device is between 0.5 h and 2 h.

[0027] The technical solution provided in this disclosure has the following advantages compared with the prior art: This disclosure provides a system and method for achieving zero-carbon emissions through coal gasification and co-production of water-soluble potassium products. The system includes a gasification unit, a cooling and purification acid gas separation unit, a roasting unit, and a carbon fixation unit. The gasification unit is used to gasify coal loaded with a potassium-containing catalyst to produce crude coal gas and gasification ash. The gasification ash, the mixture, and oxygen are activated in the roasting unit to produce solid materials and flue gas. The cooling and purification acid gas separation unit cools the crude coal gas and flue gas and separates carbon dioxide from them to obtain coal gas, carbon dioxide, and saline wastewater. The carbon fixation unit reacts carbon dioxide, saline wastewater, and solid materials to produce carbonates and water-soluble potassium products. In other words, the gasification ash generated by the gasification unit is activated by the roasting device with potassium raw materials and calcium-containing solid waste to generate solid materials. The carbon fixation device cools and separates the solid materials and the crude coal gas generated by the gasification unit to react with saline wastewater, carbon dioxide and other substances to generate carbonates and water-soluble potassium products, thereby achieving carbon dioxide fixation and zero carbon emissions, and also producing water-soluble potassium products that can be used as catalysts for the gasification reaction in the gasification unit. Attached Figure Description

[0028] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0029] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 This is a schematic diagram of the system for achieving zero carbon emissions through coal catalytic gasification and co-production of water-soluble potassium products as described in this disclosure. Figure 2 This disclosure presents a flowchart of a method for co-producing water-soluble potassium products using a system that achieves zero carbon emissions through coal catalytic gasification.

[0031] The components include: 1. Gasification unit; 11. Crude gas outlet; 12. Ash and slag outlet; 13. Gas inlet; 2. Cooling and purification acid gas separation unit; 21. Cooling inlet; 22. Carbon dioxide outlet; 23. Saline wastewater outlet; 24. Cooling outlet; 25. Cooling and purification unit; 26. Acid gas separation unit; 3. Roasting unit; 31. First inlet; 32. Second inlet; 33. First outlet; 34. Second outlet; 35. Feed port; 4. Carbon fixation unit; 41. Carbon fixation inlet; 42. Carbon fixation outlet; 5. Conversion and separation unit; 51. Conversion inlet; 6. Solid-liquid separation unit. Separation device; 61. Solid-liquid inlet; 7. Coal preparation device; 71. Liquid inlet; 72. Material inlet; 73. Coal outlet; 81. Gas-solid separation device; 811. Gas-solid separation inlet; 812. Fly ash outlet; 82. Waste heat recovery device; 821. Waste heat inlet; 822. Steam outlet; 823. Crude gas outlet; 91. Grinding device; 911. Grinding inlet; 912. Material outlet; 92. Cooling and heat recovery device; 921. Recovery inlet; 922. Recovery outlet; 93. Crushing device; 931. Crushing inlet; 932. Crushing outlet. Detailed Implementation

[0032] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0033] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0034] Example 1 Reference Figure 1 As shown, this embodiment provides a system for co-producing water-soluble potassium products by coal gasification with zero carbon emissions, including a gasification unit 1, a cooling and purification acid gas separation unit 2, a roasting unit 3, and a carbon fixation unit 4.

[0035] The gasification unit 1 is used to gasify coal loaded with a potassium-containing catalyst to produce crude coal gas and gasification ash. The gasification unit 1 has a crude coal gas outlet 11 for discharging the crude coal gas and an ash outlet 12 for discharging the gasification ash. Specifically, the gasification unit 1 also has an air inlet 13 for allowing steam and oxygen to enter. The gasification unit 1 is used to allow the coal loaded with the potassium-containing catalyst to undergo a coal gasification reaction with steam and oxygen to produce crude coal gas and gasification ash. The crude coal gas can be discharged through the crude coal gas outlet 11 to the subsequent cooling and purification acid gas separation unit 2, while the gasification ash enters the roasting unit 3 through the ash outlet 12 to be activated with the mixture in the roasting unit 3.

[0036] Specifically, coal loaded with potassium catalyst is crushed and screened to form pulverized coal smaller than 2mm. The pulverized coal is then mixed with water-soluble potassium catalyst, impregnated, and dried to obtain the coal loaded with potassium catalyst. The moisture content of the coal is less than 8%.

[0037] In this embodiment, the gasification device 1 can specifically be a pressurized fluidized bed gasifier. The gasification temperature of the gasification device 1 for the coal gasification reaction is 700-850℃, and the gasification pressure is 2.5-4.5MPa. After gasification, a crude coal gas rich in methane, syngas, and carbon dioxide with a high temperature and pressure is obtained, as well as gasification ash containing potassium. The potassium in the gasification ash exists in two forms: water-soluble and water-insoluble. The water-soluble potassium (K) is potassium carbonate and potassium sulfate, while the water-insoluble potassium is mainly potassium aluminosilicate.

[0038] The roasting device 3 has a first inlet 31 connected to the ash outlet 12 for supplying gasified ash, a second inlet 32 ​​for supplying mixed materials, and a third inlet for supplying oxygen, so that the gasified ash, mixed materials, and oxygen are activated within the roasting device 3 to generate solid materials and flue gas. The roasting device 3 also has a first outlet 33 for discharging flue gas and a second outlet 34 for discharging solid materials.

[0039] In practice, the potassium feldspar obtained from mining is used as potassium raw material. It is mixed and crushed with calcium-containing solid waste from chlor-alkali, phosphorus chemical or calcium carbide digestion industries, etc., and then mixed with potassium-containing gasification ash from the catalytic gasification process of the gasification unit and potassium-containing solid fly ash from the crude coal gas generated by gasification. The mixture is then sent to the roasting unit 3 for activation treatment.

[0040] It should be noted that the purpose of adding calcium-containing solid waste is to disrupt the stable crystal structure of insoluble potassium aluminosilicate in potassium feldspar, potassium-containing gasification ash, or potassium-containing solid fly ash during the activation process in roasting unit 3. This allows the calcium-containing solid waste to be converted into calcium silicates and aluminosilicates, which are more readily reacted with carbon dioxide. The process parameters for activation can be specifically set according to the type of calcium-containing solid waste used.

[0041] For example, if calcium chloride from the chlor-alkali industry is used as calcium-containing solid waste, the required activation temperature is 700-900℃ and the activation time is 1-3h. The reactions that occur during the roasting activation process are as follows: KAlSi3O8 + 0.5CaCl2 → 0.5CaAl2Si2O8 + 2SiO2 + KCl; KAlSiO4 + 0.5CaCl2 → 0.5CaAl2Si2O8 + KCl.

[0042] For example, if phosphogypsum from the phosphoric acid industry is used as a calcium-containing solid waste, the required activation temperature is 1000-1300℃ and the activation time is 1.5-4h. The reactions that occur during the calcination activation process are as follows: 2KAlSi3O8+ CaSO4→CaAl2Si2O8+ K2SO4 + CaSiO3; 2KAlSiO4+ CaSO4→CaAl2Si2O8+K2SO4.

[0043] For example, if calcium oxide is used, the required activation temperature is 150-300℃, the activation time is 1-3h, and the reactions that occur are: CaO + KAlSi3O8 + H2O → CaSiO3 + CaAl2Si2O8 + KOH; CaO + 2KAlSiO4 + H2O → CaAl2Si2O8 + 2KOH.

[0044] It should be noted that the activation temperature and activation time of the above three different calcium-containing solid wastes are determined according to the specific reaction kinetic requirements. The activation reaction can proceed at the optimal rate under the activation temperature and activation time. However, if the activation temperature is too high, it will result in increased energy consumption, higher requirements for equipment materials, and increased investment. If the activation temperature is too low, the activation reaction will be slow and incomplete. If the activation time is too short, the reaction will be incomplete. If the activation time is too long, the equipment size will be increased and the processing capacity will be limited.

[0045] It should be noted that, in order to reduce the temperature and energy consumption during the activation process in the roasting device 3, a certain type of additive can be added to activate non-water-soluble potassium minerals such as potassium feldspar at low temperatures. Specifically, an alcohol amine additive can be used, preferably triethanolamine. The low-temperature activation treatment temperature is 150-250℃, and the activation time is 1-3 hours. Setting the activation temperature to 150-250℃ and the activation time to 1-3 hours ensures the effectiveness of the activation reaction, that is, the additive forms a complex with Al3+ in potassium feldspar to promote the dissolution of Al3+ in potassium feldspar, thereby breaking the stable crystal structure of potassium feldspar and catalyzing its conversion into calcium aluminosilicates and silicates under low-temperature conditions.

[0046] In addition, the mass ratio of calcium-containing solid waste to water-soluble potassium-containing minerals such as potassium feldspar can be controlled to 1-3. After roasting and activation treatment, water-soluble potassium salts and other solid materials can be easily reacted with carbon dioxide produced by coal gasification to form aluminosilicates and silicates that can fix CO2.

[0047] The cooling inlet 21 of the cooling and purifying acid gas separation device 2 is connected to the first outlet 33 and the crude coal gas outlet 11, respectively. The cooling and purifying acid gas separation device 2 is used to cool the crude coal gas and flue gas and separate the carbon dioxide in the crude coal gas and flue gas to obtain coal gas, carbon dioxide and saline wastewater. The cooling and purifying acid gas separation device 2 has a carbon dioxide outlet 22 for carbon dioxide discharge and a saline wastewater outlet 23 for saline wastewater discharge.

[0048] The carbon fixation device 4 has a carbon fixation inlet 41 connected to the second outlet 34, the saline wastewater outlet 23, and the carbon dioxide outlet 22, respectively. This allows carbon dioxide, saline wastewater, and solid materials to react within the carbon fixation device 4 to generate carbonates and water-soluble potassium products, thereby achieving carbon dioxide fixation and achieving zero carbon emissions while producing water-soluble potassium products that can be used as catalysts in coal gasification. It should be noted that the water-soluble potassium products can also be used as potash fertilizer.

[0049] In summary, the system for co-producing water-soluble potassium products through coal gasification with zero carbon emissions provided in this embodiment includes a gasification unit 1, a cooling and purification acid gas separation unit 2, a roasting unit 3, and a carbon fixation unit 4. The gasification unit 1 is used to gasify coal loaded with a potassium-containing catalyst to generate crude coal gas and gasification ash. The gasification ash is sent to the roasting unit 3 for activation treatment with the mixture and oxygen therein to generate solid materials and flue gas. The cooling and purification acid gas separation unit 2 is used to cool and purify the crude coal gas generated by the gasification unit 1 and the flue gas generated by the roasting unit 3, and to separate the carbon dioxide to obtain coal gas, carbon dioxide, and saline wastewater. The carbon dioxide and saline wastewater are sent to the carbon fixation unit 4, as are the solid materials. The carbon fixation unit 4 allows the carbon dioxide, saline wastewater, and solid materials to react within the unit to generate carbonates and water-soluble potassium products. In other words, the gasification ash, solid fly ash, potassium raw materials, and calcium-containing solid waste generated by the gasification unit 1 are activated by the roasting device 3 to generate solid materials. The carbon fixation device 4 reacts the solid materials with saline wastewater, carbon dioxide, etc. to generate carbonates and water-soluble potassium products, thereby achieving carbon dioxide fixation and zero carbon emissions, and also producing water-soluble potassium products that can be used as catalysts for the gasification reaction of the gasification unit 1.

[0050] Reference Figure 1 As shown, the system also includes a conversion and separation device 5. The conversion inlet 51 of the conversion and separation device 5 is connected to the cooling outlet 24 of the cooling and purification acid gas separation device 2. The conversion and separation device 5 is used to convert the coal gas entering through the conversion inlet 51 to form chemicals and natural gas.

[0051] In other words, the crude coal gas generated by the coal gasification reaction in gasification unit 1 is cooled and separated by acid gas separation unit 2 to form coal gas. The main components of this coal gas are methane and syngas. The methane and syngas then enter conversion and separation unit 5 for conversion and separation. This mainly includes the conversion and utilization of syngas and the separation of mixed products. The conversion and utilization of syngas can involve methanation to obtain methane products, or other conversions, such as the preparation of high-value-added chemicals like olefins, methanol, and aromatics. Different catalyst systems and reaction processes are used depending on the products obtained, and natural gas and high-value-added chemicals are obtained after separation.

[0052] Reference Figure 1 As shown, the system also includes a solid-liquid separation device 6, which has a solid-liquid inlet 61 connected to the carbon fixation outlet 42 of the carbon fixation device 4. The solid-liquid separation device 6 is used to perform solid-liquid separation on carbonate and water-soluble potassium products to obtain carbonate and water-soluble potassium solutions.

[0053] In practice, carbonates and water-soluble potassium products can be fed into a solid-liquid separation device 6 for solid-liquid separation to obtain a water-soluble potassium solution mainly composed of potassium chloride, potassium sulfate, potassium hydroxide, and potassium carbonate. Part of this water-soluble potassium solution can be passed into a gasification device 1 as a potassium-containing catalyst, while part of the water-soluble potassium solution can be evaporated and crystallized to obtain solid potassium fertilizer. The separated solid material is mainly composed of calcium and magnesium carbonates, which can be used as raw materials and additives for cement and building materials.

[0054] Reference Figure 1 As shown, the system also includes a coal preparation device 7, which has a liquid inlet 71 connected to the solid-liquid separation device 6 and a material inlet 72 for coal to enter, so that the water-soluble potassium solution and coal are mixed in the coal preparation device 7 to form coal loaded with a potassium-containing catalyst. That is, the water-soluble potassium solution, mainly composed of potassium chloride, potassium sulfate, potassium hydroxide, and potassium carbonate, separated by the solid-liquid separation device 6 can be used as a potassium-containing catalyst, thus forming coal loaded with a potassium-containing catalyst that can undergo coal gasification reaction in the gasification device 1 after mixing with the coal. The coal preparation device 7 has a coal outlet 73 connected to the gasification device 1 to supply coal to the gasification device 1.

[0055] Reference Figure 1 As shown, the system also includes a gas-solid separation device 81, which has a gas-solid separation inlet 811 connected to the gasification device 1. The gas-solid separation device 811 is used to separate the crude coal gas discharged through the crude coal gas outlet 11 to obtain crude coal gas and solid fly ash. The gas-solid separation device 81 has a fly ash outlet 812 for discharging solid fly ash, which is connected to the roasting device 3, so that the gasification ash and solid fly ash produced by the gasification device 1 enter the roasting device 3 and are mixed with the mixed materials for activation treatment.

[0056] Specifically, the high-temperature and high-pressure crude coal gas rich in methane, syngas, and carbon dioxide generated by the coal gasification reaction in the gasification unit 1 enters the gas-solid separation unit 81 for gas-solid separation to obtain crude coal gas and solid fly ash. The gas-solid separation unit 8 removes the solid fly ash contained in the crude coal gas and sends the solid fly ash directly to the roasting unit 3 through the fly ash outlet 812. The crude coal gas separated by the gas-solid separation unit 8 enters the waste heat recovery unit 82.

[0057] The waste heat recovery device 82 has a waste heat inlet 821 connected to the gas-solid separation device 81. The waste heat recovery device 82 is used to cool the crude coal gas entering through the waste heat inlet 821 and the flue gas activated by the roasting device 3 to form crude coal gas and water vapor. The waste heat recovery device 82 has a water vapor outlet 822 connected to the air inlet 13 to provide water vapor to the gasification device 1. The waste heat recovery device 82 also has a crude coal gas outlet 823 connected to the cooling and purification acid gas separation device 2 to send the crude coal gas to the cooling and purification acid gas separation device 2 for cooling, purification and separation.

[0058] In practice, the crude coal gas and flue gas after passing through the waste heat recovery device 82 enter the cooling and purification acid gas separation device 2 for cooling and purification. The cooling and purification acid gas separation device 2 includes a cooling and purification device 25 and an acid gas separation device 26. The cooling and purification device 25 is used to cool the crude coal gas and flue gas and to wash and cool the carbon dioxide in the crude coal gas and flue gas with water to further remove a small amount of dust from the crude coal gas. The cooling and purification device 25 will generate a certain amount of saline wastewater containing alkali metals such as potassium, sodium, calcium, and magnesium, as well as alkaline earth metal salts. The dust-removed crude coal gas enters the acid gas separation device 26, while the saline wastewater enters the carbon fixation device 4.

[0059] In practice, the acid gas separation device 26 is used to separate carbon dioxide from the crude coal gas after it has been cooled and purified by the cooling and purification device 25, in order to obtain carbon dioxide and coal gas. The carbon dioxide is sent to the carbon fixation device 4 through the carbon dioxide outlet 22 for fixation, and the coal gas is methane and syngas, which can be further converted and utilized.

[0060] Reference Figure 1 As shown, the system also includes a grinding device 91, which has a grinding inlet 911 for potassium raw materials and calcium-containing solid waste to enter. The grinding device 91 is used to grind the potassium raw materials and calcium-containing solid waste to form a mixture.

[0061] Furthermore, it also includes a cooling and heat recovery device 92, which has a recovery inlet 921 connected to the second outlet 34. The cooling and heat recovery device 92 is used to cool the solid material entering through the recovery inlet 921. The cooling and heat recovery device 92 has a recovery outlet 922 for discharging the solid material.

[0062] The system also includes a crushing device 93, which has a crushing inlet 931 connected to the recovery outlet 922. The crushing device 93 is used to crush solid materials and has a crushing outlet 932 connected to the carbon fixation inlet 4. The crushed solid materials enter the carbon fixation device 4 and react with carbon dioxide and saline wastewater to generate carbonates and water-soluble potassium products. This achieves carbon dioxide fixation and zero carbon emissions while simultaneously producing water-soluble potassium products that can be used as gasification catalysts or potassium fertilizers.

[0063] Specifically, the solid material after roasting and activation treatment is cooled and heat recovered by the cooling and heat recovery device 92, and the by-product steam is used for the catalytic gasification process of the gasification device 1. After cooling, the solid material is crushed by the crushing device 93 to obtain particles with a particle size of less than 0.2 mm, which are then sent to the subsequent carbon fixation device 4 for carbon fixation treatment. The carbon fixation device 4 uses carbon dioxide generated by the catalytic gasification process as the reaction gas source to convert the unstable calcium and magnesium aluminosilicates and silicates in the solid material into stable carbonates. At the same time, saline wastewater generated by the catalytic gasification process is introduced into the carbon fixation device 4, and the calcium and magnesium compounds in the wastewater can be solidified by carbon dioxide. The main reactions are as follows: CaAl2Si2O8 + CO2 + H2O → CaCO3 + Al2O3·2SiO2; CaSiO3 + CO2 + H2O → CaCO3 + H4SiO4.

[0064] For example, the mass ratio of saline wastewater to solid material can be controlled at 3:1-5:1, converting calcium and magnesium salts in the saline wastewater into calcium carbonate and magnesium carbonate, which then solidify. To ensure uniform contact between the gas, liquid, and solid phases, a stirring element is installed in the carbon fixation device 4. The stirring rate is controlled at 200-500 r / min, and the reaction time is 0.5-2 h. This converts aluminosilicates and silicates into stable carbonates. (The stirring rate and time are to ensure a more complete reaction. Too fast stirring will create a vortex flow field in the carbon fixation device, causing uneven gas distribution and reducing the carbon fixation effect. Too fast stirring will also result in uneven contact between the three phases. The reaction time is determined based on the specific reaction rate; a short time will result in insufficient reaction, while a long time will reduce the device's processing capacity.) Simultaneously, the carbon dioxide produced by the catalytic gasification process is fixed, achieving zero carbon emissions from the catalytic gasification process. The partial pressure of carbon dioxide is controlled at 2-5 MPa, and the molar ratio of CO2 to calcium in the solid material is 1-3. The partial pressure of CO2 is determined based on the specific reaction. Since the reaction involves a decrease in gas volume, pressurization is beneficial. However, excessive pressure increases energy consumption, necessitating CO2 pressurization. A pressure of 2-5 MPa is considered in relation to the existing coal chemical separation section, better matching the pressure system of the carbon fixation unit. Maintaining a CO2 molar ratio of 1-3 times that of Ca ensures that all calcium aluminosilicates are converted to calcium carbonate. A slight excess ensures faster reaction kinetics, and the excess CO2 can react with calcium and magnesium salts in the wastewater to solidify into calcium carbonate and magnesium carbonate, achieving the treatment of concentrated brine while simultaneously solidifying more carbon dioxide. Too much CO2 will lead to excessively high gas pressure in the carbon fixation unit.

[0065] The carbon fixation device 4 can specifically be a high-pressure reactor, which has a three-phase state of gas, liquid, and solid. Carbon dioxide gas from the acid gas separator 26 and saline wastewater from the cooling and purification device 25 are fed into the carbon fixation device 4, where they react with the solid material activated and crushed from the upstream roasting device 3. The main process is to convert the unstable calcium and magnesium aluminosilicates in the gasification ash into stable carbonates. Simultaneously, the calcium and magnesium salts in the saline wastewater are converted into calcium carbonate and magnesium carbonate, which are then solidified. The high-pressure reactor is equipped with a stirring system. Under the stirring action, the aluminosilicates are converted into stable carbonates, and the carbon dioxide generated by the catalytic gasification process is fixed, thus achieving carbon emission reduction in the catalytic gasification process.

[0066] In practice, the roasting device 3 also has a feed port 35 for pulverized coal to be fed into the roasting device 3. Since the roasting activation temperature in the roasting device 3 is relatively high, the residual carbon in the potassium-containing gasification ash and solid fly ash produced by the gasification device 1 provides the heat required for the activation reaction by releasing heat through the activation treatment with oxygen. If the residual carbon in the gasification ash or solid fly ash is insufficient to provide the required carbon, a certain amount of pulverized coal needs to be added. Part of the carbon dioxide emitted from the activation treatment reacts directly with calcium-containing waste, potassium feldspar, etc. to form carbonates, and the other part leaves the roasting device 3 in the form of hot flue gas and is sent to the waste heat recovery device 82 and the cooling and purification device 25. It is then captured in the acid gas separation device 26 and subsequently fixed back into the carbonate product, ensuring that the entire process is carbon-free.

[0067] In summary, this embodiment combines catalytic gasification with the utilization of abundant natural potassium feldspar, solving the problems of high cost of K catalysts, difficulty in recovering potassium from gasification ash, and large carbon emissions and wastewater volume in existing catalytic gasification processes. While fixing a large amount of carbon dioxide generated by coal chemical industry, it can also obtain water-soluble potassium catalysts required for catalytic gasification and co-produce scarce water-soluble potassium fertilizer, meeting China's potassium fertilizer demand.

[0068] In addition, by directly combining the solid fly ash and alkaline gasification ash produced by the catalytic gasification process with the roasting and activation treatment process of potassium feldspar, the problems of difficult conversion of solid fly ash and difficult catalyst recovery in the catalytic gasification process are solved. At the same time, the residual carbon in the gasification ash is utilized. While achieving near-zero carbon dioxide emissions, the saline wastewater from coal gasification is also efficiently utilized, realizing the resource utilization of saline wastewater.

[0069] Example 2 Reference Figure 2 As shown, this embodiment provides a method for co-producing water-soluble potassium products using a system that achieves zero carbon emissions through coal gasification. This method is implemented by performing all or part of the system for co-producing water-soluble potassium products using coal gasification that achieves zero carbon emissions in Example 1, so as to achieve zero carbon emissions and co-produce water-soluble potassium products that can be used as catalysts for the gasification reaction.

[0070] The method specifically includes the following steps: S101: Coal loaded with potassium catalyst is introduced into the gasification unit so that the coal loaded with potassium catalyst undergoes a gasification reaction in the gasification unit to generate crude coal gas and gasification ash. S102: The generated gasified ash, oxygen and mixture are sent to the calcination unit for activation treatment to generate solid materials and flue gas; S103: The generated crude coal gas and flue gas are sent to the cooling and purification acid gas separation device to separate coal gas, carbon dioxide and saline waste liquid. S104: Solid materials, separated carbon dioxide, and saline waste liquid are sent to a carbon fixation unit for reaction to produce carbonates and water-soluble potassium products.

[0071] In practice, the gasification unit is used to gasify coal loaded with a potassium-containing catalyst to produce crude coal gas and gasification ash. The gasification ash is sent to a roasting unit for activation treatment with the mixture and oxygen therein to produce solid materials and flue gas. The cooling, purification, and acid gas separation unit is used to cool and purify the crude coal gas from the gasification unit and the flue gas from the roasting unit, and to separate the carbon dioxide to obtain coal gas, carbon dioxide, and saline wastewater. The carbon dioxide and saline wastewater are sent to a carbon fixation unit, where the solid materials are also sent. The carbon fixation unit allows the carbon dioxide, saline wastewater, and solid materials to react to produce carbonates and water-soluble potassium products. In other words, the gasification ash, solid fly ash, potassium raw materials, and calcium-containing solid waste generated by the gasification unit are activated by the roasting device to generate solid materials. The carbon fixation device reacts the solid materials with saline wastewater and carbon dioxide to generate carbonates and water-soluble potassium products, thereby achieving carbon dioxide fixation and zero carbon emissions. The co-production of water-soluble potassium products can also be used as a catalyst for the gasification reaction in the gasification unit.

[0072] In step S104, to ensure uniform contact between the gas, liquid, and solid phases within the carbon fixation device, a stirring device can be used to agitate the device, converting aluminosilicates, silicates, etc., into stable carbonates. The stirring speed of the stirring device is between 200 r / min and 500 r / min, and the reaction time within the carbon fixation device is between 0.5 h and 2 h. It should be noted that the stirring rate and reaction time are designed to ensure a more complete reaction. Too rapid stirring will create a vortex flow field within the carbon fixation device, causing uneven gas distribution and reducing the carbon fixation effect; too rapid stirring will also result in uneven contact between the three phases. The reaction time is determined based on the specific reaction rate; a short time results in insufficient reaction, while a long time reduces the device's processing capacity.

[0073] According to one embodiment of this disclosure, after the step of sending the generated crude coal gas and flue gas to a cooling and purification acid gas separation device to separate coal gas, carbon dioxide and saline waste liquid, the method further includes: sending the separated coal gas to a conversion separation device for conversion to generate chemicals and natural gas.

[0074] In other words, the crude coal gas produced by the coal gasification reaction in the gasification unit is cooled and separated by an acid gas separation unit to form coal gas. The main components of this coal gas are methane and syngas. The methane and syngas then enter a conversion and separation unit for further processing. This mainly includes the conversion and utilization of syngas and the separation of mixed products. The conversion and utilization of syngas can involve methanation to obtain methane products, or other conversions, such as the preparation of high-value-added chemicals like olefins, methanol, and aromatics. Different catalyst systems and reaction processes are used depending on the products obtained, and the resulting natural gas and high-value-added chemicals are obtained through separation.

[0075] According to one embodiment of this disclosure, after the step of sending solid materials, separated carbon dioxide, and saline waste liquid to a carbon fixation device for reaction to generate a mixture of carbonates and water-soluble potassium solution, the method further includes: sending the carbonates and water-soluble potassium solution to a solid-liquid separation device for solid-liquid separation to obtain a water-soluble potassium solution mainly composed of potassium chloride, potassium sulfate, potassium hydroxide, and potassium carbonate. A portion of this water-soluble potassium solution can be passed into a gasification device as a potassium-containing catalyst, while a portion of the water-soluble potassium solution is evaporated and crystallized to obtain solid potassium fertilizer. The separated solid material is mainly composed of calcium and magnesium carbonates, which can be used as raw materials and additives for cement and building materials.

[0076] According to one embodiment of this disclosure, after the steps of obtaining carbonate and water-soluble potassium solution, the method further includes: feeding the water-soluble potassium solution into a coal preparation unit for use as a water-soluble potassium catalyst. The water-soluble potassium solution is then mixed with and dried with coal in the coal preparation unit to form coal loaded with a potassium-containing catalyst.

[0077] In practice, the mixture can be formed by crushing potassium feldspar and calcium-containing solid waste. The mass ratio of calcium-containing solid waste to potassium feldspar in the mixture is between 1 and 3. It should be noted that controlling the mass ratio of calcium-containing solid waste to potassium feldspar to 1-3 ensures that the calcium-containing solid waste contains enough calcium to displace the potassium from the potassium feldspar, ensuring a complete and sufficient reaction. This avoids problems such as insufficient displacement reaction due to insufficient calcium content, or waste and increased load on subsequent processing due to excessive calcium content.

[0078] For example, if calcium chloride from the chlor-alkali industry is used as calcium-containing solid waste, the required activation temperature is 700-900℃ and the activation time is 1-3h. The reactions that occur during the roasting activation process are as follows: KAlSi3O8 + 0.5CaCl2 → 0.5CaAl2Si2O8 + 2SiO2 + KCl; KAlSiO4 + 0.5CaCl2 → 0.5CaAl2Si2O8 + KCl.

[0079] For example, if phosphogypsum from the phosphoric acid industry is used as a calcium-containing solid waste, the required activation temperature is 1000-1300℃ and the activation time is 1.5-4h. The reactions that occur during the calcination activation process are as follows: 2KAlSi3O8 + CaSO4 → CaAl2Si2O8 + K2SO4 + CaSiO3; 2KAlSiO4 + CaSO4 → CaAl2Si2O8 + K2SO4.

[0080] For example, if calcium oxide is used, the required activation temperature is 150-300℃ and the activation time is 1-3h. The reactions that occur are: CaO + KAlSi3O8 + H2O → CaSiO3 + CaAl2Si2O8 + KOH; CaO + 2KAlSiO4 + H2O → CaAl2Si2O8 + 2KOH.

[0081] It should be noted that the activation temperature and activation time of the above three different calcium-containing solid wastes are determined according to the specific reaction kinetic requirements. The activation reaction can proceed at the optimal rate under the activation temperature and activation time. However, if the activation temperature is too high, it will result in increased energy consumption, higher requirements for equipment materials, and increased investment. If the activation temperature is too low, the activation reaction will be slow and incomplete. If the activation time is too short, the reaction will be incomplete. If the activation time is too long, the equipment size will be increased and the processing capacity will be limited.

[0082] Alternatively, an additive can be introduced into the calcination apparatus to coordinate with potassium feldspar, thereby reducing the activation temperature and time within the apparatus. For example, after adding the additive, the activation temperature in the calcination apparatus is between 150℃ and 250℃, and the activation time is between 1 hour and 3 hours. The additive can specifically be triethanolamine. Setting the activation temperature to 150-250℃ and the activation time to 1-3 hours ensures the effectiveness of the activation reaction; that is, the additive forms a complex with Al3+ in the potassium feldspar, promoting the dissolution of Al3+ and thus breaking the stable crystal structure of potassium feldspar, allowing it to catalyze the conversion of potassium feldspar into calcium aluminosilicates and silicates under low-temperature conditions.

[0083] In addition, the mass ratio of saline wastewater to solid materials is 3:1-5:1; the partial pressure of carbon dioxide is between 2MPa and 5MPa; and the molar ratio of carbon dioxide to calcium in the solid materials is between 1 and 3. For example, controlling the mass ratio of saline wastewater to solid materials to 3:1-5:1 allows the calcium and magnesium salts in the saline wastewater to be converted into calcium carbonate and magnesium carbonate, which are then solidified. The specific partial pressure of CO2 is determined based on the specific reaction. Since the reaction involves a decrease in gas volume, pressurization is beneficial, but excessive pressure increases energy consumption, necessitating CO2 pressurization. 2-5MPa is considered in relation to the pressure of existing coal chemical separation sections, better matching the pressure system of the carbon fixation unit. Maintaining a CO2 molar ratio of 1-3 times that of Ca ensures that all calcium aluminosilicates are converted into calcium carbonate. A slight excess ensures faster reaction kinetics, and the excess CO2 can react with the calcium and magnesium salts in the wastewater to convert them into calcium carbonate and magnesium carbonate, thus treating the saline wastewater and simultaneously solidifying more carbon dioxide. Excessive CO2, however, will lead to excessively high gas pressure in the carbon fixation unit.

[0084] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0085] The above description is merely a specific embodiment of this disclosure, enabling those skilled in the art to understand or implement it. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this disclosure. Therefore, this disclosure is not to be limited to the embodiments described herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions, characterized in that, It includes a gasification unit (1), a cooling and purification acid gas separation unit (2), a roasting unit (3), and a carbon fixation unit (4). The gasification device (1) is used to gasify coal loaded with potassium catalyst to generate crude coal gas and gasification ash. The gasification device (1) has a crude coal gas outlet (11) for discharging the crude coal gas and an ash outlet (12) for discharging the gasification ash. The roasting device (3) has a first inlet (31) connected to the ash outlet (12), a second inlet (32) for the mixed material to enter, and a third inlet for oxygen to enter, so that the gasified ash, the mixed material, and the oxygen are activated in the roasting device (3) to generate solid material and flue gas; the roasting device (3) has a first outlet (33) for the flue gas to be discharged and a second outlet (34) for the solid material to be discharged; the mixed material is potassium feldspar and calcium-containing solid waste; The cooling inlet (21) of the cooling and purifying acid gas separation device (2) is connected to the first outlet (33) and the crude coal gas outlet (11) respectively. The cooling and purifying acid gas separation device (2) is used to cool the crude coal gas and the flue gas and separate the carbon dioxide in the crude coal gas and the flue gas to obtain coal gas, carbon dioxide and saline wastewater. The cooling and purifying acid gas separation device (2) has a carbon dioxide outlet (22) for carbon dioxide discharge and a saline wastewater outlet (23) for saline wastewater discharge. The carbon fixation device (4) has a carbon fixation inlet (41) that is connected to the second outlet (34), the saline wastewater outlet (23) and the carbon dioxide outlet (22) respectively, so that the carbon dioxide, the saline wastewater and the solid material react in the carbon fixation device (4) to generate carbonate and water-soluble potassium products.

2. The system for co-producing water-soluble potassium products through coal gasification with zero carbon emissions according to claim 1, characterized in that, It also includes a conversion separation device (5), the conversion inlet (51) of which is connected to the cooling outlet (24) of the cooling and purification acid gas separation device (2), the conversion separation device (5) being used to convert the coal gas entering through the conversion inlet (51) to form chemicals and natural gas.

3. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 1, characterized in that, It also includes a solid-liquid separation device (6), which has a solid-liquid inlet (61) connected to the solid carbon outlet (42) of the solid carbon device (4). The solid-liquid separation device (6) is used to perform solid-liquid separation on the carbonate and water-soluble potassium products entering through the solid-liquid inlet (61) to obtain carbonate and water-soluble potassium solutions.

4. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 3, characterized in that, It also includes a coal preparation device (7), which has a liquid inlet (71) connected to the solid-liquid separation device (6) and a material inlet (72) for coal to enter, so that the water-soluble potassium solution and the coal are mixed in the coal preparation device (7) to form the coal loaded with potassium catalyst; the coal preparation device has a coal outlet (73) connected to the gasification device (1) to provide the coal loaded with potassium catalyst to the gasification device (1).

5. The system for co-producing water-soluble potassium products by coal gasification according to any one of claims 1 to 4, characterized in that, It also includes a gas-solid separation device (81), which has a gas-solid separation inlet (811) connected to the crude coal gas outlet (11). The gas-solid separation device (81) is used to perform gas-solid separation on the crude coal gas to obtain crude coal gas and solid fly ash. The gas-solid separation device (81) has a fly ash outlet (812) for discharging the solid fly ash. The fly ash outlet (812) is connected to the roasting device (3).

6. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 5, characterized in that, It also includes a waste heat recovery device (82); the waste heat recovery device (82) has a waste heat inlet (821) connected to the gas-solid separation device (81) and the first outlet (33) respectively, the waste heat recovery device (82) is used to cool the crude coal gas and the flue gas to form crude coal gas and water vapor; the waste heat recovery device (82) has a water vapor outlet (822) connected to the gasification device (1) and a crude coal gas outlet (823) connected to the cooling and purification acid gas separation device (2).

7. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 6, characterized in that, The cooling and purification acid gas separation device (2) includes a cooling and purification device (25), the cooling inlet (21) is located on the cooling and purification device (25), and the cooling inlet (21) is connected to the crude coal gas outlet (823). The cooling and purification device (25) is used to cool the crude coal gas and separate the carbon dioxide in the crude coal gas to obtain cooled crude coal gas and saline wastewater. The saline wastewater outlet (23) is located on the cooling and purification device (25).

8. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 7, characterized in that, The cooling and purification acid gas separation device (2) includes an acid gas separation device (26) connected to the cooling and purification device (25). The acid gas separation device (26) is used to separate carbon dioxide in the cooled crude coal gas to obtain carbon dioxide and the coal gas. The carbon dioxide outlet (22) is located on the acid gas separation device (26).

9. The system for co-producing water-soluble potassium products by coal gasification according to any one of claims 1 to 4, characterized in that, It also includes a grinding device (91), which has a grinding inlet (911) for entering potassium raw material and calcium-containing solid waste, and is used to grind the potassium raw material and the calcium-containing solid waste to form the mixture; the grinding device (91) has a material outlet (912) for discharging the mixture, and the material outlet (912) is connected to the second inlet (32); the potassium raw material is potassium feldspar.

10. The system for co-producing water-soluble potassium products by coal gasification according to any one of claims 1 to 4, characterized in that, It also includes a cooling and heat recovery device (92), which has a recovery inlet (921) connected to the second outlet (34), and is used to cool the solid material entering through the recovery inlet (921); the cooling and heat recovery device (92) has a recovery outlet (922) for the solid material to be discharged.

11. The system for co-producing water-soluble potassium products via coal gasification to achieve zero carbon emissions according to claim 10, characterized in that, It also includes a crushing device (93) having a crushing inlet (931) connected to the recovery outlet (922), the crushing device (93) being used to crush the solid material, and the crushing device (93) having a crushing outlet (932) connected to the carbon inlet (41).

12. The system for co-producing water-soluble potassium products by coal gasification according to any one of claims 1 to 4, characterized in that, The roasting device (3) also has a feed port (35) for feeding pulverized coal into the roasting device (3).

13. A method for co-producing water-soluble potassium products using a system for achieving zero carbon emissions through coal gasification as described in any one of claims 1 to 12, characterized in that, The method includes: Coal loaded with a potassium catalyst is introduced into the gasification device so that the coal loaded with the potassium catalyst undergoes a gasification reaction in the gasification device to generate crude coal gas and gasification ash. The generated gasified ash, oxygen, and mixture are sent to a calcination unit for activation treatment to generate solid materials and flue gas. The generated crude coal gas and flue gas are sent to a cooling and purification acid gas separation device to separate coal gas, carbon dioxide and saline waste liquid. The solid material, the separated carbon dioxide, and the saline waste liquid are sent to a carbon fixation device for reaction to generate carbonate and water-soluble potassium products.

14. The method according to claim 13, characterized in that, After the step of sending the generated crude coal gas and the flue gas to a cooling and purification acid gas separation device to separate coal gas, carbon dioxide and saline waste liquid, the method further includes: The separated coal gas is sent to a conversion and separation unit for conversion to produce chemicals and natural gas.

15. The method according to claim 13, characterized in that, After the step of sending the solid material, the separated carbon dioxide, and the saline waste liquid to a carbon fixation device for reaction to generate a mixture of carbonate and water-soluble potassium solution, the method further includes: The carbonate and the water-soluble potassium solution are sent to a solid-liquid separation device for solid-liquid separation to obtain the carbonate and the water-soluble potassium solution.

16. The method according to claim 13, characterized in that, The step of sending the generated gasified ash, oxygen, and mixture to a calcination device for activation treatment to generate solid materials and flue gas includes: Potassium feldspar and calcium-containing solid waste are mixed and crushed to form a mixture. The mixture is mixed with the gasification ash and solid fly ash obtained by coal gasification reaction in the gasification device and then sent to the roasting device. Oxygen is introduced into the roasting device to activate the oxygen, the mixture, the gasified ash, and the solid fly ash within the roasting device, thereby generating the solid material and the flue gas.

17. The method according to claim 16, characterized in that, The mass ratio of the calcium-containing solid waste to the potassium feldspar in the mixture is between 1 and 3.

18. The method according to claim 16, characterized in that, The calcium-containing solid waste is calcium chloride, and the activation temperature in the roasting device is between 700℃ and 900℃, while the activation time in the roasting device is between 1h and 3h. The calcium-containing solid waste is solid waste phosphogypsum, the activation temperature is between 1000℃ and 1300℃, and the activation time is between 1.5h and 4h. The calcium-containing solid waste is calcium oxide, the activation temperature is between 150℃ and 300℃, and the activation time is between 1h and 3h.

19. The method according to claim 16, characterized in that, Prior to the step of introducing oxygen into the roasting apparatus to activate the oxygen, the mixture, the gasified ash, and the solid fly ash within the roasting apparatus, the method further includes: An additive is introduced into the calcining apparatus to combine with the potassium feldspar in the mixture; wherein the activation temperature in the calcining apparatus is between 150°C and 250°C; and the activation time in the calcining apparatus is between 1 hour and 3 hours.

20. The method according to claim 13, characterized in that, The mass ratio of the saline wastewater to the solid material is 3:1 to 5:1; the partial pressure of carbon dioxide is between 2 MPa and 5 MPa; and the molar ratio of carbon dioxide to calcium in the solid material is between 1 and 3.

21. The method according to claim 13, characterized in that, When the solid material, the separated carbon dioxide, and the saline waste liquid are sent to the carbon fixation device for reaction to generate carbonate and water-soluble potassium products, the carbon fixation device is stirred by a stirring device; wherein the stirring speed of the stirring device is between 200 r / min and 500 r / min, and the reaction time in the carbon fixation device is between 0.5 h and 2 h.

Images