Dry catalytic deacidification agent for removing flue gas and preparation method and application system thereof

Abstract

The present invention provides a dry catalytic deacidifying agent for removing flue gas, a preparation method thereof and an application system, which belong to the technical field of flue gas purification. The dry catalytic deacidifying agent for removing flue gas comprises, by mass percentage, 42.7% - 88% of high specific surface area calcium hydroxide, 1.0% - 10.0% of cobalt nitrate and 11.0% - 49.0% of composite oxide. The specific surface area of the high specific surface area calcium hydroxide is ≥ 40 m 2 / g, and the dry catalytic deacidifying agent further comprises an auxiliary agent. The present invention prepares a catalytic deacidifying agent precursor with highly dispersed main active components and auxiliary agents through a mixing method, and obtains the catalytic deacidifying agent through kneading and molding; the dry catalytic deacidifying agent prepared by the mixing method of the present invention has high deacidification efficiency, with a SO2 removal rate > 94%, an HF removal rate > 90%, and an HCl removal rate > 90%; the application system of the present invention has a full-process anhydrous process, does not generate desulfurization wastewater, and there is no problem of equipment corrosion.

Description

Technical Field

[0001] The invention belongs to the technical field of flue gas purification, and in particular relates to a dry catalytic deacidification agent for removing flue gas, a preparation method thereof and an application system thereof. Background Art

[0002] A large amount of flue gas is generated during the production of electrolytic aluminum. In addition to hydrogen fluoride, fluoride, and dust, the flue gas also contains a large amount of SO 2 , its SO 2 The concentration is 100mg / Nm 3 ~300mg / Nm 3 Most of the fluoride in the flue gas comes from the fluoride salt in the electrolytic cell, which volatilizes at high temperatures and is released with the flue gas. Long-term exposure can cause fluoride poisoning, affecting the health of teeth and bones; SO 2 It is mainly produced by the sulfur in the raw materials and the electrolytic reaction. It has a strong pungent odor and can cause respiratory diseases. Therefore, the flue gas of electrolytic aluminum enterprises must be deeply purified before it can be discharged into the atmosphere. With the implementation of the "ultra-low emission" policy for flue gas in various regions, it is required to reduce SO 2 The concentration is controlled at 35mg / Nm 3 Below, almost all the flue gas of electrolytic aluminum enterprises needs to be deeply desulfurized and defluorinated.

[0003] At present, the main flue gas desulfurization methods for aluminum electrolysis include wet desulfurization and dry desulfurization; the wet flue gas desulfurization technology that has been implemented is mainly the limestone-gypsum wet desulfurization technology used in the power industry. Several aluminum electrolytic enterprises that have adopted this technology for wet desulfurization technology transformation have reported that although the wet technology has high desulfurization efficiency, it is not suitable for the aluminum electrolytic industry. The main reason is that the most commonly used wet desulfurization method is the limestone-gypsum method. This method uses limestone slurry to absorb sulfur dioxide in the flue gas to generate calcium sulfate (gypsum), which has a high efficiency and stable desulfurization effect. However, the acidic substances in the flue gas during the wet desulfurization process will cause serious corrosion to the equipment, especially when dealing with flue gas containing corrosive gases. The corrosion problem of the equipment is more serious, which not only affects the life of the equipment, but may also cause equipment failure and affect the desulfurization efficiency. In addition, the wet desulfurization technology requires the flue gas after washing to be reheated, which is a step with high energy consumption and increased operating costs. In summary, the unique pollution factors in the flue gas of the electrolytic aluminum industry will cause serious secondary pollution and other subsequent problems in the wet desulfurization process, which are mainly manifested as follows: First, the flue gas of electrolytic aluminum is rich in fluoride ions, and the post-treatment of the desulfurization wastewater containing fluoride ions is extremely difficult and expensive; second, the desulfurization wastewater containing fluoride ions is extremely corrosive to the equipment, and the desulfurization equipment put into operation will face corrosion overhaul problems in about one year; third, the desulfurization gypsum produced by wet desulfurization is difficult to treat and requires high costs.

[0004] The dry desulfurization processes currently implemented mainly include activated carbon adsorption, electron beam irradiation, etc. These methods are only suitable for specific scenarios, but the technology is complex and the cost is high; and there are no application examples in the actual electrolytic aluminum flue gas desulfurization environment. Summary of the invention

[0005] Based on the problems existing in the prior art, the present invention proposes a dry catalytic deacidifier for removing flue gas and its preparation method and application system, which solves the problems of high cost, secondary pollution, equipment corrosion and so on in the existing wet desulfurization technology, and meets the market demand for deep purification of flue gas in the electrolytic aluminum industry.

[0006] In order to achieve the above-mentioned object, according to the first aspect of the technical solution of the present invention, the present invention provides a dry catalytic deacidification agent for removing flue gas, the dry catalytic deacidification agent for removing flue gas comprises 42.7% to 88% of high specific surface calcium hydroxide, 1.0% to 10.0% of cobalt nitrate and 11.0% to 49.0% of composite oxide in mass percentage, the specific surface area of ​​the high specific surface calcium hydroxide is ≥40m 2 / g, the dry catalytic deacidification agent further includes an auxiliary agent.

[0007] Preferably, the auxiliary agent is potassium molybdate, the mass percentage of the auxiliary agent to the total mass of the dry catalytic deacidification agent is 2.0-5.0%, and the composite oxide is any one of magnesium oxide and titanium dioxide.

[0008] According to the second aspect of the technical solution of the present invention, the present invention provides a method for preparing a dry catalytic deacidification agent for removing flue gas, which comprises the following steps:

[0009] Step S1: preparation of a catalytic deacidification agent precursor;

[0010] Step S2: kneading and forming the catalytic deacidifying agent;

[0011] Step S1 further includes step S11, wherein 42.7% to 88% of high-specific calcium hydroxide, 1.0% to 10.0% of cobalt nitrate and 2.0% to 5.0% of an additive are mixed into solution I according to mass percentage; wherein the high-specific calcium hydroxide is first placed in a certain amount of water and stirred for 5 minutes, and then the cobalt nitrate and the additive are added and stirred for 30 minutes;

[0012] Step S1 further includes step S12, wherein an alkaline precipitant and water glass are prepared into solution II; specifically, the alkaline precipitant and water glass are weighed in a ratio of 1:1 by mass, and the alkaline precipitant in a ratio of 1:1 by mass is added to the water glass and stirred for 10 minutes; the alkaline precipitant is one or both of urea or ammonium bicarbonate solution;

[0013] Step S13, adding solution I and solution II into a reactor in parallel and performing an aging reaction; and step S14, filtering the slurry after the aging reaction to obtain a filter cake, washing the filter cake with deionized water and drying it to obtain a catalytic deacidification agent precursor;

[0014] Step S2 further includes step S21, adding a certain amount of catalytic deacidification agent precursor prepared in step S1, an appropriate amount of composite oxide and one or two of methyl cellulose and field sesbania powder, using dilute acid or silica sol as a binder, using a silane coupling agent as a molding aid, kneading for 10 to 60 minutes to form a mass, and then extruding it into a shape.

[0015] According to a third aspect of the technical solution of the present invention, the present invention provides an application system of a dry catalytic deacidification agent, the application system of the dry catalytic deacidification agent comprises a bottom plate, a pretreatment device is fixedly connected to one side of the bottom plate, a bag dust removal mechanism is fixedly connected to the top of the bottom plate, and a deacidification mechanism is fixedly connected to the other side of the bottom plate; the deacidification mechanism comprises a cylinder, one side of the cylinder is connected to a smoke exhaust pipe, a rotating pipe is arranged on the top of the cylinder, a first pulley is fixedly connected to the surface of the rotating pipe, a mounting frame is fixedly connected to one side of the cylinder, a second motor is fixedly connected to the top of the mounting frame, a second pulley is fixedly connected to the output end of the second motor, the second pulley is connected to the first pulley through a belt transmission connection, a second connecting pipe is connected to the top of the rotating pipe, the bottom of the rotating pipe passes through the top of the cylinder and extends to the inner cavity of the cylinder, a nozzle is connected to the surface of the rotating pipe, and a distribution plate is fixedly connected to the surface of the rotating pipe and located below the nozzle; the flue gas enters the interior of the cylinder through the smoke exhaust pipe, and is connected to the feeding device of the catalytic deacidification agent through the second connecting pipe, the catalytic deacidification agent is transported to the nozzle through the inside of the rotating pipe, and is evenly sprayed on the surface of the distribution plate through the nozzle.

[0016] Preferably, the pretreatment device includes a box body, the bottom of one side of the box body is connected to a smoke inlet pipe, a cooling box is fixedly connected to one side above the bottom plate and below the box body, one side of the cooling box is connected to a first connecting pipe, one side of the first connecting pipe is connected to a circulation pump, one side of the circulation pump is connected to a circulation pipe, one side of the circulation pipe passes through one side of the box body and extends to the inner cavity of the box body.

[0017] Preferably, the side of the circulation pipe away from the circulation pump is connected to the spray rack through a hose, the upper side of one side of the box body is fixedly connected to a shell, and one side of the shell is fixedly connected to the first motor.

[0018] Preferably, the output end of the first motor passes through the inner cavity of the outer shell and is fixedly connected to a circular gear, and the inner cavity of the outer shell is movably connected to a sector gear via a bearing.

[0019] More preferably, the sector gear meshes with the circular gear, a rotating rod is fixedly connected to the surface of the sector gear, a side of the rotating rod away from the sector gear penetrates into the inner cavity of the box, and one side of the rotating rod is fixedly connected to the spray rack.

[0020] Furthermore, the bag dust removal mechanism includes a shell, the bottom of the shell is fixedly connected to the base plate, the bottom of the shell is connected to a cleaning bucket, the top of the shell is connected to a delivery pipe, the side of the delivery pipe away from the shell is connected to the box body, the inner cavity of the shell is fixedly connected to a bag dust collector, and the top of one side of the shell is connected to a smoke exhaust pipe.

[0021] Furthermore, there are four distribution plates, and flow channels are opened on the surface of the distribution plates, and the flow channels are distributed in a circular pattern; the bottom of the cylinder is fixedly connected to a base frame, the bottom of the base frame is fixedly connected to the bottom plate, and the bottom of one side of the cylinder is connected to a smoke exhaust pipe.

[0022] Compared with the prior art, the dry catalytic deacidification agent for removing flue gas and its preparation method and application system of the present invention have the following advantages and positive effects:

[0023] 1. The dry catalytic deacidification agent for removing flue gas and its preparation method of the present invention adopts a mixed method to prepare a catalytic deacidification agent with high deacidification efficiency. 2 The removal rate is >94%, the HF removal rate is >90%, and the HCl removal rate is >90%. The system uses an anhydrous process throughout the entire process, does not produce desulfurization wastewater, and does not have equipment corrosion problems.

[0024] 2. The dry catalytic deacidification agent for removing flue gas and the preparation method thereof of the present invention use high specific surface area calcium hydroxide, which has higher desulfurization efficiency and lower investment cost. The desulfurization efficiency of high specific surface area calcium hydroxide can reach more than 94%, or even more than 95%, while the desulfurization efficiency of ordinary calcium hydroxide is relatively low. In addition, the high specific surface area calcium hydroxide dry desulfurization process requires less investment, low operating costs, and does not require a grinding system, which further reduces investment and operating costs.

[0025] 3. The application system of the dry catalytic deacidifier for removing flue gas of the present invention is a fully water-free process, which does not generate secondary pollution and other wastes. The flue gas in the electrolytic aluminum production process does not require secondary heating, and the energy consumption is low. The catalytic desulfurizer is small in size, occupies a small area, and requires a small investment. In addition, the desulfurizer loaded with the dry catalytic desulfurizer has much smaller resistance than the wet desulfurization tower, and has low operating costs.

[0026] 4. The application system of the dry catalytic deacidification agent for removing flue gas of the present invention adopts a pretreatment device that can be flexibly adjusted according to the temperature, dust content and composition characteristics of the flue gas in different industrial scenarios, so that the entire system can adapt to the flue gas treatment needs of various different working conditions. Whether it is high-concentration or low-concentration acid gas flue gas, the application system can effectively respond. Through efficient deacidification treatment, the emission of acid gas is significantly reduced, the occurrence of environmental problems such as acid rain is effectively reduced, and the ecological environment and human health are protected. At the same time, the pollution of water bodies by a large amount of wastewater generated by wet deacidification is avoided, and the generation of secondary pollutants is reduced from the source. In addition, the stability and long-life operation characteristics of the application system reduce the maintenance and replacement frequency of equipment, reduce the full life cycle cost of equipment, and help enterprises improve their economic benefits and social image.

[0027] 5. The application system of the dry catalytic deacidifier for removing flue gas of the present invention pre-treats the flue gas. On the one hand, it effectively avoids the reduction of the activity of the catalytic deacidifier due to excessively high temperature and prolongs the service life of the catalytic deacidifier. On the other hand, it prevents the condensation of acidic gas caused by excessively low temperature and affects the subsequent deacidification reaction, ensuring that the deacidification reaction can be carried out efficiently at an appropriate temperature. The use of bag dust collector can efficiently remove dust and particulate matter in the flue gas, with a removal rate of more than 99%. This not only protects subsequent equipment and avoids the reduction of the activity of the catalytic deacidifier due to the clogging of the pores by particulate matter, but also prevents the damage to the structure of the catalytic deacidifier due to wear, thereby maintaining the long-term stable performance of the catalytic deacidifier, reducing the replacement frequency of the catalytic deacidifier, and reducing operating costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic diagram of the three-dimensional structure of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention;

[0029] Figure 2 A schematic cross-sectional view of a cylinder structure of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention;

[0030] Figure 3 A schematic diagram of the structure of a distribution plate of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention;

[0031] Figure 4 A schematic cross-sectional view of the shell structure of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention;

[0032] Figure 5 A schematic cross-sectional view of a shell structure of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention;

[0033] Figure 6The figure is a side view schematic diagram of the box structure of an application system of a dry catalytic deacidification agent for removing flue gas according to the present invention.

[0034] Explanation of reference numerals in the accompanying drawings: 1. bottom plate; 2. pre-treatment device; 201. box body; 202. smoke inlet pipe; 203. cooling box; 204. first connecting pipe; 205. circulation pump; 206. circulation pipe; 207. spray rack; 208. housing; 209. first motor; 210. circular gear; 211. sector gear; 212. rotating rod; 3. bag dust removal mechanism; 301. housing; 302. cleaning bucket; 303, conveying pipe; 304, bag filter; 305, smoke exhaust pipe; 4, deacidification mechanism; 401, cylinder; 402, rotating pipe; 403, first pulley; 404, mounting frame; 405, second motor; 406, second pulley; 407, second connecting pipe; 408, nozzle; 409, distribution plate; 5, flow channel; 6, base frame; 7, smoke exhaust pipe; 8, sprayer; 9, conditioner. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0037] The present invention provides a dry catalytic deacidification agent for removing flue gas, a preparation method thereof and an application system thereof, which belong to the technical field of flue gas purification. The dry catalytic deacidification agent for removing flue gas comprises 42.7% to 88% of high-specific surface calcium hydroxide, 1.0% to 10.0% of cobalt nitrate and 11.0% to 49.0% of composite oxide in terms of mass percentage, and the specific surface area of ​​the high-specific surface calcium hydroxide is ≥40m 2 / g, the dry catalytic deacidification agent further includes an auxiliary agent. In a preferred embodiment, the composite oxide is one or two of magnesium oxide and titanium dioxide, the auxiliary agent is potassium molybdate, and the mass percentage of the auxiliary agent to the total mass of the dry catalytic deacidification agent is 2.0-5.0%. The present invention obtains a catalytic deacidification agent precursor with a highly dispersed main active component and auxiliary agent by a mixing method, and obtains a catalytic deacidification agent by kneading and molding; the catalytic deacidification agent prepared by the mixing method of the present invention has high deacidification efficiency, SO 2The removal rate is >94%, the HF removal rate is >90%, and the HCl removal rate is >90%. The whole process is water-free, no desulfurization wastewater is generated, and there is no equipment corrosion problem. The pretreatment device can be flexibly adjusted according to the temperature, dust content and composition characteristics of the flue gas in different industrial scenarios, so that the whole system can adapt to the flue gas treatment needs of various working conditions. Through efficient deacidification treatment, the emission of acidic gases is significantly reduced.

[0038] In the present invention, high specific surface area calcium hydroxide adopts a calcium hydroxide product with an extremely high specific surface area. Specific surface area is an important parameter to measure the ratio of the surface area to the volume of a substance. A high specific surface area means more reaction sites, thereby improving the reaction efficiency and performance of the substance. The high specific surface area calcium hydroxide in the present invention generally has a specific surface area of ​​40 to 60 square meters per gram (m² / g), which is 2 to 3 times the specific surface area of ​​ordinary calcium hydroxide. In a preferred embodiment, the specific surface area of ​​the high specific surface area calcium hydroxide is ≥40m 2 / g. ‌

[0039] ‌Cobalt nitrate is an inorganic compound with the chemical formula CO(NO 3 ) 2 , usually in the form of red crystals or particles. Cobalt nitrate is easily soluble in water and alcohol, soluble in acetone, and has oxidizing properties. Contact with flammable materials may cause fire or explosion. Composite oxides are oxides formed by the combination of two or more metal elements and oxygen. In a preferred embodiment, the composite oxide is one of titanium dioxide and magnesium oxide. Titanium dioxide reacts with SO during low-temperature sintering. 2 It has the best adsorption performance and good desulfurization performance; magnesium oxide can be used as a desulfurizer to react with sulfur oxides (such as sulfur dioxide) to generate solid magnesium sulfate or magnesium sulfite, thereby reducing the emission of sulfur oxides. Potassium molybdate is often used as a catalyst and auxiliary agent. The role of potassium molybdate as an auxiliary agent in the desulfurization process is mainly reflected in its catalytic effect. Potassium molybdate can be used as a catalyst to promote the desulfurization reaction. Potassium molybdate can improve the desulfurization efficiency and reduce the emission of harmful gases. ‌‌

[0040] In another embodiment, a method for preparing a dry catalytic deacidification agent for removing flue gas comprises the following steps:

[0041] Step S1: preparation of a catalytic deacidification agent precursor;

[0042] Step S2: kneading and forming the catalytic deacidifying agent;

[0043] Step S1 further includes step S11, wherein 42.7% to 88% of high-specific calcium hydroxide, 1.0% to 10.0% of cobalt nitrate and 2.0% to 5.0% of an additive are mixed into solution I according to mass percentage; wherein the high-specific calcium hydroxide is first placed in a certain amount of water and stirred for 5 minutes, and then the cobalt nitrate and the additive are added and stirred for 30 minutes;

[0044] Step S1 further includes step S12, wherein an alkaline precipitant and water glass are prepared into solution II; specifically, the alkaline precipitant and water glass are weighed in a ratio of 1:1 by mass, and the alkaline precipitant in a ratio of 1:1 by mass is added to the water glass and stirred for 10 minutes; the alkaline precipitant is one or both of urea or ammonium bicarbonate solution;

[0045] Step S13, adding solution I and solution II into a reactor in parallel and performing an aging reaction; and step S14, filtering the slurry after the aging reaction to obtain a filter cake, washing the filter cake with deionized water and drying it to obtain a catalytic deacidification agent precursor;

[0046] Step S2 further includes step S21, adding a certain amount of catalytic deacidification agent precursor prepared in step S1, an appropriate amount of composite oxide and one or two of methyl cellulose and field sesbania powder, using dilute acid or silica sol as a binder, using a silane coupling agent as a molding aid, kneading for 10 to 60 minutes to form a mass, and then extruding it into a shape.

[0047] In a preferred embodiment, the alkaline precipitant is one or both of urea and ammonium bicarbonate solution; the composite oxide is one of titanium dioxide and magnesium oxide; and the dilute acid is one of nitric acid, citric acid, and acetic acid.

[0048] The present invention provides a dry catalytic deacidification agent application system comprising a base plate, a pretreatment device fixedly connected to one side of the base plate, a bag dust removal mechanism fixedly connected to the top of the base plate, and a deacidification mechanism fixedly connected to the other side of the base plate. The deacidification mechanism includes a cylinder, one side of the cylinder is connected to the smoke exhaust pipe, a rotating pipe is arranged on the top of the cylinder, a first pulley is fixedly connected to the surface of the rotating pipe, a mounting frame is fixedly connected to one side of the cylinder, a second motor is fixedly connected to the top of the mounting frame, an output end of the second motor is fixedly connected to the second pulley, the second pulley is connected to the first pulley through a belt, a second connecting pipe is connected to the top of the rotating pipe, the bottom of the rotating pipe passes through the top of the cylinder and extends to the inner cavity of the cylinder, a nozzle is connected to the surface of the rotating pipe, a distribution plate is fixedly connected to the surface of the rotating pipe and located below the nozzle, smoke enters the interior of the cylinder through the smoke exhaust pipe, a feeding device for catalytic deacidification agent is connected through the second connecting pipe, the catalytic deacidification agent is transported to the nozzle through the interior of the rotating pipe, and is evenly sprayed on the surface of the distribution plate through the nozzle, the second motor is started by the controller, the second motor drives the second pulley to rotate, and the second pulley drives the first The pulley rotates, and the first pulley drives the rotating tube to rotate, and the rotating tube drives the distribution plate and the nozzle to rotate. During the rotation of the distribution plate, the catalytic deacidifier can be evenly distributed in the tower, which greatly increases the contact area between the catalytic deacidifier and the flue gas. Compared with the traditional single-layer structure, the multi-layer distribution plate can effectively increase the contact area, ensuring that the flue gas can fully contact with the catalytic deacidifier during transportation, improve the reaction efficiency, and remove the acid gas more fully. By setting up the cylinder, using solid materials and reasonable structural design, it can withstand high temperature, high pressure and other harsh conditions. The multi-layer distribution plate inside is reasonably designed and not prone to blockage, deformation and other problems, ensuring the long-term and stable deacidification reaction. Good sealing effectively prevents flue gas leakage, ensures the safety of operators, and avoids pollution to the surrounding environment. The efficient thermal insulation performance reduces heat loss and maintains the temperature in the tower stable, which is conducive to the continuous deacidification reaction, reduces energy consumption, and improves the energy utilization efficiency of the system.

[0049] In one embodiment, the number of distribution plates is four, and flow channels are opened on the surface of the distribution plates. The flow channels are distributed circumferentially and evenly distributed on the surface of the distribution plates, which can effectively increase the contact area between the distribution plates and the flue gas. At the same time, the catalytic deacidifying agent can be evenly sprayed on the surface of the distribution plate flow channels, thereby increasing the neutralization effect of the flue gas and the catalytic deacidifying agent.

[0050] In one embodiment, the pretreatment device includes a box body, the bottom of one side of the box body is connected to a smoke inlet pipe, a side above the bottom plate and located below the box body is fixedly connected to a cooling box, one side of the cooling box is connected to a first connecting pipe, one side of the first connecting pipe is connected to a circulation pump, one side of the circulation pump is connected to a circulation pipe, one side of the circulation pipe passes through one side of the box body and extends to the inner cavity of the box body, the side of the circulation pipe away from the circulation pump is connected to a spray rack through a hose, a shell is fixedly connected to the top of one side of the box body, one side of the shell is fixedly connected to a first motor, the output end of the first motor passes through the inner cavity of the shell and is fixedly connected to a circular gear, the inner cavity of the shell is movably connected to a fan gear through a bearing, the fan gear is meshed with the circular gear, the surface of the fan gear is fixedly connected to a rotating rod, the The side of the rotating rod away from the fan gear penetrates into the inner cavity of the box body, and one side of the rotating rod is fixedly connected to the spray rack. The smoke enters the interior of the box body through the smoke inlet pipe at the bottom of one side of the box body, and a fan is arranged on the top of the smoke inlet pipe. The smoke is continuously input into the interior of the box body under the action of the fan. By starting the circulation pump, the circulation pump extracts the coolant inside the cooling box through the first connecting pipe, and transports it to the interior of the spray rack through the circulation pipe. The coolant cools the smoke through the nozzle at the bottom of the spray rack. At the same time, by starting the first motor, the first motor drives the circular gear to rotate, the circular gear drives the fan gear to rotate, the fan gear drives the rotating rod to rotate, and the rotating rod drives the spray rack to rotate, so that the spray angle of the spray rack can be adjusted. During the rotation process, the contact area between the coolant and the smoke is guaranteed, the cooling effect is improved, and the purpose of rapid cooling is achieved.

[0051] The water-cooling method can accurately control the high-temperature flue gas temperature to 100℃~200℃, which matches the optimal temperature range of the deacidification reaction. On the one hand, it effectively avoids the reduction of the activity of the catalytic deacidification agent due to excessively high temperature and prolongs the service life of the catalytic deacidification agent. On the other hand, it prevents the condensation of acidic gases due to excessively low temperature, which affects the subsequent deacidification reaction and ensures that the deacidification reaction can be carried out efficiently at an appropriate temperature.

[0052] Furthermore, the bag-type dust removal mechanism includes a shell, the bottom of which is fixedly connected to the bottom plate, the bottom of which is connected to a cleaning bucket, the top of which is connected to a conveying pipe, the side of which is away from the shell and is connected to a box body, the inner cavity of the shell is fixedly connected to a bag-type dust collector, the top of one side of the shell is connected to a smoke exhaust pipe, the cooled flue gas enters the interior of the shell through the conveying pipe, and under the action of the bag-type dust collector, dust and particulate matter in the flue gas can be removed, impurities and particles are discharged through the bottom of the shell, and the flue gas enters the interior of the deacidification mechanism through the smoke exhaust pipe for deacidification treatment. During the flue gas transportation process, the conditioner is started, and the conditioner sprays an appropriate amount of water vapor or other additives into the flue gas, thereby optimizing the humidity and composition of the flue gas.

[0053] The use of bag dust collector can effectively remove dust and particulate matter in the flue gas, with a removal rate of more than 99%. This not only protects subsequent equipment and prevents the catalytic deacidifier from reducing its activity due to particulate matter clogging its pores, but also prevents wear from damaging the structure of the catalytic deacidifier, thereby maintaining the long-term stability of the catalytic deacidifier, reducing the replacement frequency of the catalytic deacidifier, and reducing operating costs. The conditioner can optimize the humidity and composition of the flue gas by spraying an appropriate amount of water vapor or other additives into the flue gas. For example, for some acidic gases with high viscosity, appropriately increasing the humidity can improve their dispersibility in the flue gas, making it easier to contact and react with the catalytic deacidifier; for specific acidic gas components, adding corresponding additives can promote chemical reactions, significantly improve the deacidification efficiency, and enhance the system's adaptability to flue gases with different components.

[0054] In one embodiment, the bottom of the cylinder is fixedly connected to a base frame, the bottom of the base frame is fixedly connected to the bottom plate, and the bottom of one side of the cylinder is connected to a smoke exhaust pipe. The cylinder is supported by the base frame to ensure the stability of the overall structure of the cylinder. At the same time, the smoke exhaust pipe can discharge the deacidified smoke, thereby improving the smoke emission effect.

[0055] Furthermore, a sprayer is connected to the surface of the delivery pipe, one side of the sprayer is connected to a conditioner, and the bottom of the conditioner is fixedly connected to the box. The conditioner can optimize the humidity and composition of the flue gas by spraying an appropriate amount of water vapor or other additives into the flue gas. For example, for some acidic gases with high viscosity, appropriately increasing the humidity can improve their dispersibility in the flue gas, making it easier for them to contact and react with the catalytic deacidification agent; for specific acidic gas components, adding corresponding additives can promote the chemical reaction, significantly improve the deacidification efficiency, and enhance the system's adaptability to flue gases with different components.

[0056] In one embodiment, a third connecting pipe is connected to the bottom of the box body, the bottom of the third connecting pipe is connected to the cooling box, the top of the third connecting pipe is connected to the box body, and the bottom of the third connecting pipe is connected to the cooling box, which can ensure the circulation of the coolant inside the box body, achieve the purpose of efficient circulation, and improve the cooling effect of the flue gas.

[0057] The technical solution of the present invention is further illustrated below through various specific embodiments.

[0058] The preparation method of the dry catalytic deacidification agent for removing flue gas of the present invention comprises the following steps:

[0059] Step S1: Preparation of a catalytic deacidification agent precursor. It further comprises the following steps:

[0060] Step S11, high specific surface calcium hydroxide, cobalt nitrate, and auxiliary agents are prepared into solution I; specifically, the high specific surface calcium hydroxide is first placed in a certain amount of water, stirred for 3min-6min, preferably 5min, cobalt nitrate and auxiliary agent potassium molybdate are added and stirred for 25min-35min, preferably 30min, and the cobalt nitrate and auxiliary agent potassium molybdate are dispersed as evenly as possible in the high specific surface calcium hydroxide by stirring, and after the later roasting step, the cobalt and potassium elements can be evenly dispersed in the calcium oxide. In a preferred embodiment, the auxiliary agent is potassium molybdate.

[0061] Step S12, alkaline precipitant and water glass are prepared into solution II;

[0062] Specifically, the alkaline precipitant and water glass are weighed in a ratio of 1:1 by mass, and the alkaline precipitant in the above ratio is added to the water glass and stirred for 8 minutes to 15 minutes, preferably 10 minutes.

[0063] In a preferred embodiment, the alkaline precipitant is one or both of urea and ammonium bicarbonate solution. Further, the alkaline precipitant is preferably urea.

[0064] Step S13, add 1000 ml of water to the reactor, heat the system to 60-95°C and start stirring, maintain normal pressure, set the stirring rate to 200-300 rpm / min, add solution I and solution II to the reactor in parallel, control the reaction time within 0.1-1 hour, preferably 45 minutes; maintain the same temperature for aging reaction for 0.5-5.0 hours, preferably 2 hours.

[0065] Step S14, after the aging reaction is completed, the slurry is filtered, the filter cake is washed with deionized water and then dried to obtain a catalytic deacidification agent precursor.

[0066] Step S2: kneading and molding the catalytic deacidification agent, adding a certain amount of the catalytic deacidification agent precursor prepared in step S1, an appropriate amount of composite oxide and one or two of methyl cellulose and sesbania powder, using dilute acid or silica sol as a binder, using a silane coupling agent as a molding aid, kneading for 10 to 60 minutes to form a mass, and then extruding and molding. Step S2 further includes the following steps:

[0067] Step S21, add a certain amount of catalytic deacidification agent precursor, one or two of appropriate composite oxides, methyl cellulose and sesbania powder, dilute acid or silica sol as a binder, silane coupling agent as a molding aid, knead for 10 minutes to 60 minutes to form a mass, and then extrude and mold, preferably 40 minutes. Specifically, take 70g of catalytic deacidification agent precursor, add 10g of magnesium oxide and 10.5g of 35% silica sol, 2.3g of methyl cellulose, 3.2g of sesbania powder, 15mL of 10% nitric acid solution, 2.0g of silane coupling agent as a molding aid, knead for 30 minutes to 60 minutes, preferably 40 minutes to form a mass, and extrude a cylindrical product.

[0068] In a preferred embodiment, the composite oxide is one of titanium dioxide and magnesium oxide, the dilute acid is one of nitric acid, citric acid, and acetic acid, and the silica sol is SiO 2 The concentration of alkaline silica sol is 35%. The amount of silane coupling agent added is 2% of the mass fraction of the catalytic deacidification agent.

[0069] Step S22, drying and calcining the formed catalytic deacidification agent. Specifically, the formed catalytic deacidification agent is placed in a high-temperature muffle furnace and heated to 150°C at a rate of 30°C / h for 2h, then heated to 350°C at a rate of 15°C / h for 1h, and finally heated to 550°C at a rate of 30°C / h for 2h.

[0070] For the dry catalytic deacidification agent prepared according to the above method of the present invention, the performance of the dry catalytic deacidification agent is evaluated or assessed, and the evaluation method is as follows:

[0071] 40 mL of the prepared catalytic deacidification agent was loaded into the fixed bed reactor and the preheated SO 2 , HCl and HF mixed gas, fixed bed reaction temperature 80 ~ 450 ℃, reaction pressure 0.1 ~ 1MPa, feed gas space velocity 100 ~ 1000h -1 The raw materials and products were analyzed using a Laoying 3023Y flue gas analyzer, and the results were corrected using the internal standard method. The flue gas removal efficiency was tested by controlling the feed rate, temperature, pressure, and mixed gas composition. The fixed bed can also directly use the application system of the dry catalytic deacidification agent provided by the present invention.

[0072] In another embodiment (Example 1), the preparation method of the dry catalytic deacidification agent for removing flue gas includes the following preparation method, which includes the steps of:

[0073] Step S1: Preparation of catalytic deacidification agent precursor. Dissolve 50g of high specific surface calcium hydroxide, 42.6g of potassium molybdate, and 11.5g of cobalt nitrate to prepare 1000mL of solution I, and dissolve 54g of urea and 10.4g of water glass to prepare 1000mL of alkaline precipitant solution II. Add 1000mL of aqueous solution to the reactor, start the stirring and heating system to 60°C, add solution I and solution II to the reactor in parallel, control the reaction time within 1.0 hour, and keep the same temperature to age the reaction solution for 5.0 hours. After the aging reaction solution is completed, filter the slurry, wash the filter cake with deionized water, and then dry it to obtain the catalytic deacidification agent precursor.

[0074] Step S2: kneading and molding the catalytic deacidification agent. Add 12.87g titanium dioxide and 12.5g 35% silica sol, 2.0g methyl cellulose, 3.0g sesbania powder, 10mL 10% nitric acid solution, and 2.34g silane coupling agent as a molding aid to the catalytic deacidification agent precursor prepared in the above step S1, knead for 10 minutes to form a mass, and then extrude it. The molded catalytic deacidification agent is dried at 120°C for 3 hours and then calcined at 400°C for 4 hours. In this embodiment, a total of 60g of oxide is added.

[0075] The performance of the catalytic deacidification agent prepared in this example was evaluated. The performance evaluation process of the catalytic deacidification agent was as follows: 40 mL of the prepared catalytic deacidification agent was loaded into a fixed bed reactor, and preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 80 ° C, pressure 0.1 MPa, feed gas space velocity 1000h -1 , the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0076] In another embodiment (Example 2), the preparation method of the dry catalytic deacidification agent for removing flue gas includes the following preparation method, which includes the steps of:

[0077] Step S1: Preparation of catalytic deacidification agent precursor. Dissolve 103g of high specific surface calcium hydroxide, 2.9g of potassium molybdate, and 1.1g of cobalt nitrate to prepare 1000mL of solution I, and dissolve 54g of ammonium bicarbonate and 10.4g of water glass to prepare 1000mL of alkaline precipitant solution II. Add 1000mL of aqueous solution to the reactor, start the stirring and heating system to 95°C, add solution I and solution II to the reactor in parallel, control the reaction time within 0.1 hour, and keep the reaction solution aged at the same temperature for 0.5 hours. After the aging reaction solution is completed, filter the slurry, wash the filter cake with deionized water, and then dry it to obtain the catalytic deacidification agent precursor.

[0078] Step S2: kneading and molding the catalytic deacidification agent. The catalytic deacidification agent precursor prepared above was added with 10g magnesium oxide and 12.5g 35% silica sol, 2.0g methyl cellulose, 3.0g sesbania powder, 10mL 10% nitric acid solution, and 2.34g silane coupling agent as a molding aid, kneaded for 60 minutes to form a mass, and then extruded to form. The molded catalytic deacidification agent was dried at 120°C for 3 hours and then calcined at 400°C for 4 hours.

[0079] The performance of the catalytic deacidification agent prepared in this example was evaluated. The performance evaluation process of the catalytic deacidification agent was as follows: 40 mL of the prepared catalytic deacidification agent was loaded into a fixed bed reactor, and preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 120 ° C, pressure 1.0 MPa, feed gas space velocity 100h -1 , the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0080] In another embodiment (Example 3), the preparation method of the dry catalytic deacidification agent for removing flue gas includes the following preparation method, which includes the steps of:

[0081] Step S1: Preparation of catalytic deacidification agent precursor. Dissolve 50g of high specific surface calcium hydroxide, 4.7g of potassium molybdate, and 5g of cobalt nitrate to prepare 1000mL of solution I, and dissolve 24g of urea and 1.4g of water glass to prepare 1000mL of alkaline precipitant solution II. Add 1000mL of aqueous solution to the reactor, start the stirring and heating system to 85°C, add solution I and solution II to the reactor in parallel, control the reaction time within 0.2 hours, and keep the same temperature to age the reaction solution for 3.0 hours. After the aging reaction solution is completed, filter the slurry, wash the filter cake with deionized water, and then dry it to obtain the catalytic deacidification agent precursor.

[0082] Step S2: kneading and molding the catalytic deacidification agent. Add 57.3g of magnesium oxide and 1.5g of 35% silica sol, 2.0g of methyl cellulose, 3.0g of sesbania powder, 10mL of 10% acetic acid solution, and 2.34g of silane coupling agent as molding aids to the catalytic deacidification agent precursor prepared above, knead for 20 minutes to form a mass, and then extrude and mold. The molded catalytic deacidification agent is dried at 120°C for 3 hours and then calcined at 400°C for 4 hours.

[0083] The performance of the catalytic deacidification agent prepared in this example was evaluated. The performance evaluation process of the catalytic deacidification agent was as follows: 40 mL of the prepared catalytic deacidification agent was loaded into a fixed bed reactor, and preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 200 ° C, pressure 0.2 MPa, feed gas space velocity 500h -1, the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0084] In another embodiment (Example 4), the preparation method of the dry catalytic deacidification agent for removing flue gas includes the following preparation method, which includes the steps of:

[0085] Step S1: Preparation of catalytic deacidification agent precursor. Dissolve 51g of high specific surface calcium hydroxide, 3.7g of potassium molybdate, and 5g of cobalt nitrate to prepare 1000mL of solution I, and dissolve 11g of ammonium bicarbonate and 6.2g of water glass to prepare 1000mL of alkaline precipitant solution II. Add 1000mL of aqueous solution to the reactor, start the stirring and heating system to 45°C, add solution I and solution II to the reactor in parallel, control the reaction time within 0.3 hours, and keep the same temperature to age the reaction solution for 2.0 hours. After the aging reaction solution is completed, filter the slurry, wash the filter cake with deionized water, and then dry it to obtain the catalytic deacidification agent precursor.

[0086] Step S2: kneading and molding the catalytic deacidification agent. Add 57.3g of magnesium oxide and 1.2g of 35% silica sol, 2.0g of methyl cellulose, 3.0g of sesbania powder, 10mL of 10% citric acid solution, and 2.34g of silane coupling agent as molding aids to the catalytic deacidification agent precursor prepared above, knead for 30 minutes to form a mass, and then extrude and mold. The molded catalytic deacidification agent is dried at 120°C for 3 hours and then calcined at 400°C for 4 hours.

[0087] The performance of the catalytic deacidification agent prepared in this example was evaluated. The performance evaluation process of the catalytic deacidification agent was as follows: 40 mL of the prepared catalytic deacidification agent was loaded into a fixed bed reactor, and preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 300 ° C, pressure 0.1 MPa, feed gas space velocity 1000h -1 , the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0088] In another embodiment (Example 5), the preparation method of the dry catalytic deacidification agent for removing flue gas includes the following preparation method, which includes the steps of:

[0089] Step S1: Preparation of catalytic deacidification agent precursor. Dissolve 55g of high specific surface calcium hydroxide, 15.7g of potassium molybdate, and 3g of cobalt nitrate to prepare 1000mL of solution I, and dissolve 11g of urea and 6.2g of water glass to prepare 1000mL of alkaline precipitant solution II. Add 1000mL of aqueous solution to the reactor, start the stirring and heating system to 45°C, add solution I and solution II to the reactor in parallel, control the reaction time within 0.3 hours, and keep the same temperature to age the reaction solution for 2.0 hours. After the aging reaction solution is completed, filter the slurry, wash the filter cake with deionized water, and then dry it to obtain the catalytic deacidification agent precursor.

[0090] Step S2: kneading and molding the catalytic deacidification agent. Add 43.3g of magnesium oxide and 4.0g of 35% silica sol, 2.0g of methyl cellulose, 3.0g of sesbania powder, 10mL of 10% nitric acid solution, and 2.34g of silane coupling agent as molding aids to the catalytic deacidification agent precursor prepared above, knead for 30 minutes to form a mass, and then extrude and mold. The molded catalytic deacidification agent is dried at 120°C for 3 hours and then calcined at 400°C for 4 hours.

[0091] The performance of the catalytic deacidification agent prepared in this example was evaluated (the catalytic deacidification agent evaluation results in the following table are represented by Example 6). The performance evaluation process of the catalytic deacidification agent was as follows: 40 mL of the prepared catalytic deacidification agent was loaded into a fixed bed reactor, and preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 450 ° C, pressure 0.1 MPa, feed gas space velocity 1000h -1 , the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0092] The dry catalytic deacidification agent for removing flue gas prepared according to the preparation method of the present invention is compared with the existing catalytic deacidification agent. The specific conditions of the comparative experiment are as follows:

[0093] 1. Calcium hydroxide with a commercial content of 92% was loaded into the same fixed bed reactor. The loading amount of calcium hydroxide with a commercial content of 92% was 40 mL. The performance evaluation process conditions were as follows: Calcium hydroxide with a commercial content of 92% was loaded into the fixed bed reactor. Preheated SO 2 , HCl and HF mixture, maintaining the fixed bed reactor temperature at 80 ° C, pressure 0.1 MPa, feed gas space velocity 1000h -1 , use Laoying 3023Y flue gas analyzer to analyze the raw materials and products;

[0094] 2. 40 mL of the prepared catalytic deacidification agent was loaded into the fixed bed reactor. The performance evaluation process conditions were as follows: preheated SO 2, HCl and HF mixture, maintaining the fixed bed reactor temperature at 80 ° C, pressure 0.1 MPa, feed gas space velocity 1000h -1 , the raw materials and products were analyzed using Laoying 3023Y flue gas analyzer.

[0095] The flue gas deacidification performance was evaluated under the same reaction process conditions, and the comparative results are shown in Table 1 below.

[0096] Evaluation data show that the catalytic deacidification agent prepared by the present invention has a high effect on SO 2 The single-pass adsorption removal rates of HF and calcium hydroxide are both >90%, while the removal rate of SO 2 The single-pass adsorption removal rates of HF and HF were both <15%.

[0097] Table 1. Evaluation results of catalytic deacidifier under flue gas simulation conditions of electrolytic aluminum enterprises

[0098] Catalytic deacidification agent Temperature / ℃ Pressure / MPa <![CDATA[SO 2 Inlet concentration mg / Nm 3 ]]> <![CDATA[HF inlet concentration mg / Nm 3 > <![CDATA[SO 2 Outlet concentration mg / Nm 3 ]]> <![CDATA[HF outlet concentration mg / Nm 3 > Example 1 80 0.1 290 103 12 3 Example 2 120 1.0 301 98 10 5 Example 3 200 0.2 345 101 11 9 Example 4 300 0.1 388 105 12 4 Example 5 450 0.1 324 108 10 4 Example 6 450 0.1 411 107 350 98

[0099] On the other hand, the present invention also provides an application system of a dry catalytic deacidification agent for removing flue gas, which is specifically applied to the deacidification of flue gas in the electrolytic aluminum industry. It is specifically a flue gas treatment system that can use the dry catalytic deacidification agent for removing flue gas in any of the above embodiments. Figure 1-Figure 6 As shown, the application system of the dry catalytic deacidification agent for removing flue gas of the present invention is specifically described as follows:

[0100] like Figure 1 As shown, the application system includes a bottom plate 1, a pretreatment device 2 is fixedly connected to one side of the bottom plate 1, a bag dust removal mechanism 3 is fixedly connected to the top of the bottom plate 1, and a deacidification mechanism 4 is fixedly connected to the other side of the bottom plate 1. In the application system of the present invention, the aforementioned dry catalytic deacidification agent is added to the application system (flue gas treatment system) through the deacidification mechanism 4; specifically, as Figure 2 and Figure 3 As shown, the flue gas enters the interior of the cylinder 401 through the smoke exhaust pipe 305, and is connected to the feeding device of the catalytic deacidifier through the second connecting pipe 407. The catalytic deacidifier is transported to the nozzle through the interior of the rotating tube, and is evenly sprayed on the surface of the distribution plate through the nozzle. That is, the catalytic deacidifier can be sprayed into the application system (flue gas treatment system) through the nozzle, so that the catalytic deacidifier contacts and reacts with the acidic gas to generate corresponding salt substances; part of these salt substances are discharged with the flue gas, and the other part is captured by the dust collector together with the dust, and is further processed after being collected by the ash removal system. The present invention uses a distribution plate to further increase the contact area and reaction time between the catalytic deacidifier and the acidic gas to improve the efficiency of the reaction.

[0101] In a preferred embodiment, the deacidification mechanism 4 includes a cylinder 401, one side of the cylinder 401 is connected to the smoke exhaust pipe 305, a rotating tube 402 is provided on the top of the cylinder 401, a first pulley 403 is fixedly connected to the surface of the rotating tube 402, a mounting frame 404 is fixedly connected to one side of the cylinder 401, a second motor 405 is fixedly connected to the top of the mounting frame 404, a second pulley 406 is fixedly connected to the output end of the second motor 405, and the second pulley 406 is transmission-connected to the first pulley 403 through a belt, a second connecting tube 407 is connected to the top of the rotating tube 402, and the bottom of the rotating tube 402 passes through the top of the cylinder 401 and extends to the inner cavity of the cylinder 401. The surface of the rotating tube 402 is connected to the nozzle 408, and a distribution plate 409 is fixedly connected to the surface of the rotating tube 402 and located below the nozzle 408. By setting the cylinder 401, a solid material and a reasonable structural design are adopted, which can withstand harsh conditions such as high temperature and high pressure. The multi-layer distribution plate 409 inside it is reasonably designed and is not prone to problems such as blockage and deformation, ensuring the long-term and stable deacidification reaction. Good sealing can effectively prevent smoke leakage, ensure the safety of operators, and avoid pollution to the surrounding environment. The efficient thermal insulation performance reduces heat loss, maintains the temperature in the tower stable, is conducive to the continuous deacidification reaction, reduces energy consumption, and improves the energy utilization efficiency of the system.

[0102] In another embodiment, the number of distribution plates 409 is four, and a flow channel 5 is opened on the surface of the distribution plate 409. The flow channel 5 is distributed in a circular shape. The flow channel 5 is evenly distributed on the surface of the distribution plate 409, which can effectively increase the contact area between the distribution plate 409 and the flue gas. At the same time, the catalytic deacidifying agent can be evenly sprayed on the surface of the flow channel 5 of the distribution plate 409, thereby increasing the neutralization effect of the flue gas and the catalytic deacidifying agent.

[0103] Furthermore, the bottom of the cylinder 401 is fixedly connected to a base frame 6, the bottom of the base frame 6 is fixedly connected to the bottom plate 1, and the bottom of one side of the cylinder 401 is connected to a smoke exhaust pipe 7. The cylinder 401 is supported by the base frame 6 to ensure the stability of the overall structure of the cylinder 401. At the same time, the smoke exhaust pipe 7 can discharge the deacidified smoke, thereby improving the smoke emission effect.

[0104] In addition, the surface of the delivery pipe 303 is connected to a sprayer 8, one side of the sprayer 8 is connected to a conditioner 9, the bottom of the conditioner 9 is fixedly connected to the box 201, and the conditioner 9 can optimize the humidity and composition of the flue gas by spraying an appropriate amount of water vapor or other additives into the flue gas. For example, for some acidic gases with high viscosity, appropriately increasing the humidity can improve their dispersibility in the flue gas, making it easier to contact and react with the catalytic deacidification agent; for specific acidic gas components, adding corresponding additives can promote the chemical reaction, significantly improve the deacidification efficiency, and enhance the adaptability of the system to flue gases with different components.

[0105] like Figure 1 , Figure 4 and Figure 6 As shown, the pretreatment device 2 includes a box body 201, a smoke inlet pipe 202 is connected to the bottom of one side of the box body 201, a cooling box 203 is fixedly connected to one side of the bottom plate 1 and located below the box body 201, a first connecting pipe 204 is connected to one side of the cooling box 203, a circulating pump 205 is connected to one side of the first connecting pipe 204, a circulating pipe 206 is connected to one side of the circulating pump 205, one side of the circulating pipe 206 passes through one side of the box body 201 and extends to the inner cavity of the box body 201, and a spray rack 207 is connected to the side of the circulating pipe 206 away from the circulating pump 205 through a hose, a shell 208 is fixedly connected to the top of one side of the box body 201, a first motor 209 is fixedly connected to one side of the shell 208, and an output end of the first motor 209 passes through the inner cavity of the shell 208 and is fixed. A circular gear 210 is connected, and the inner cavity of the housing 208 is movably connected to a sector gear 211 through a bearing. The sector gear 211 meshes with the circular gear 210. A rotating rod 212 is fixedly connected to the surface of the sector gear 211. The side of the rotating rod 212 away from the sector gear 211 penetrates into the inner cavity of the box body 201. One side of the rotating rod 212 is fixedly connected to the spray rack 207. The water cooling method is adopted to accurately control the temperature of the high-temperature flue gas to 100-200°C, which matches the optimal temperature range of the deacidification reaction. On the one hand, it effectively avoids the reduction of the activity of the catalytic deacidification agent due to excessively high temperature and prolongs the service life of the catalytic deacidification agent. On the other hand, it prevents the condensation of acidic gas due to excessively low temperature, which affects the subsequent deacidification reaction, and ensures that the deacidification reaction can be carried out efficiently at an appropriate temperature.

[0106] like Figure 6 As shown, the bottom of the box body 201 is connected to a third connecting pipe, the bottom of the third connecting pipe is connected to the cooling box 203, the top of the third connecting pipe is connected to the box body 201, and the bottom is connected to the cooling box 203, which can ensure the circulation of the coolant inside the box body 201, achieve the purpose of efficient circulation, and improve the cooling effect of the flue gas.

[0107] like Figure 5As shown, the bag dust removal mechanism 3 includes a shell 301, the bottom of the shell 301 is fixedly connected to the bottom plate 1, the bottom of the shell 301 is connected to a cleaning bucket 302, the top of the shell 301 is connected to a delivery pipe 303, the side of the delivery pipe 303 away from the shell 301 is connected to the box 201, the inner cavity of the shell 301 is fixedly connected to a bag dust collector 304, and the top of one side of the shell 301 is connected to a smoke exhaust pipe 305. The bag dust collector 304 can effectively remove dust and particulate matter in the flue gas, and the removal rate can reach more than 99%. This not only protects the subsequent equipment, but also prevents the catalytic deacidification agent from being blocked by particulate matter. It reduces the activity and prevents the damage of the catalytic deacidifier structure by wear, thereby maintaining the long-term stability of the catalytic deacidifier, reducing the replacement frequency of the catalytic deacidifier and reducing the operating cost. The conditioner 9 can optimize the humidity and composition of the flue gas by spraying an appropriate amount of water vapor or other additives into the flue gas. For example, for some acidic gases with high viscosity, appropriately increasing the humidity can improve their dispersibility in the flue gas, making it easier to contact and react with the catalytic deacidifier; for specific acidic gas components, adding corresponding additives can promote the chemical reaction, significantly improve the deacidification efficiency, and enhance the system's adaptability to flue gases with different components.

[0108] The specific configuration and functions of the pretreatment device 2, the bag dust removal mechanism 3 and the deacidification mechanism 4 will be described in detail below in conjunction with a specific embodiment.

[0109] like Figure 1 and Figure 4 As shown, the pretreatment device 2 includes a box body 201, the bottom of the box body 201 is connected to a third connecting pipe, the bottom of the third connecting pipe is connected to a cooling box 203, the bottom of one side of the box body 201 is connected to a smoke inlet pipe 202, one side above the bottom plate 1 and located below the box body 201 is fixedly connected to the cooling box 203, one side of the cooling box 203 is connected to a first connecting pipe 204, one side of the first connecting pipe 204 is connected to a circulation pump 205, one side of the circulation pump 205 is connected to a circulation pipe 206, one side of the circulation pipe 206 passes through one side of the box body 201 and extends to the inner cavity of the box body 201, and the circulation pipe 206 is away from the circulation pump 20 5 is connected to a spray rack 207 through a hose, a shell 208 is fixedly connected to the top of one side of the box body 201, a first motor 209 is fixedly connected to one side of the shell 208, an output end of the first motor 209 passes through the inner cavity of the shell 208 and is fixedly connected to a circular gear 210, the inner cavity of the shell 208 is movably connected to a fan gear 211 through a bearing, the fan gear 211 is meshed with the circular gear 210, a rotating rod 212 is fixedly connected to the surface of the fan gear 211, a side of the rotating rod 212 away from the fan gear 211 passes through the inner cavity of the box body 201, and one side of the rotating rod 212 is fixedly connected to the spray rack 207.

[0110] The smoke enters the interior of the box body 201 through the smoke inlet pipe 202 at the bottom of one side of the box body 201. A fan is arranged on the top of the smoke inlet pipe 202. The smoke is continuously input into the interior of the box body 201 under the action of the fan. By starting the circulation pump 205, the circulation pump 205 extracts the coolant in the cooling box 203 through the first connecting pipe 204, and transports it to the interior of the spray rack 207 through the circulation pipe 206. The coolant cools the smoke through the nozzle at the bottom of the spray rack 207. At the same time, by starting the first motor 209, the first motor 209 drives the circular gear 210 to rotate, the circular gear 210 drives the fan gear 211 to rotate, the fan gear 211 drives the rotating rod 212 to rotate, and the rotating rod 212 drives the spray rack 207 to rotate, so that the spray angle of the spray rack 207 can be adjusted. During the rotation process, the contact area between the coolant and the smoke is guaranteed, the cooling effect is improved, and the purpose of rapid cooling is achieved.

[0111] The effect achieved by the entire pretreatment device 2 is that the water-cooling method can accurately control the high-temperature flue gas temperature to 100-200°C, which matches the optimal temperature range of the deacidification reaction. On the one hand, it effectively avoids the reduction of the activity of the catalytic deacidification agent due to excessively high temperature and extends the service life of the catalytic deacidification agent. On the other hand, it prevents the condensation of acidic gases due to excessively low temperature, which affects the subsequent deacidification reaction, thereby ensuring that the deacidification reaction can be carried out efficiently at an appropriate temperature.

[0112] like Figure 1 and Figure 5 As shown, the bag dust removal mechanism 3 includes a shell 301, the bottom of the shell 301 is fixedly connected to the bottom plate 1, the bottom of the shell 301 is connected to a cleaning bucket 302, the top of the shell 301 is connected to a delivery pipe 303, the surface of the delivery pipe 303 is connected to a sprayer 8, one side of the sprayer 8 is connected to a conditioner 9, the bottom of the conditioner 9 is fixedly connected to the box 201, the side of the delivery pipe 303 away from the shell 301 is connected to the box 201, the inner cavity of the shell 301 is fixedly connected to a bag dust collector 304, and the top of one side of the shell 301 is connected to a smoke exhaust pipe 305.

[0113] The cooled flue gas enters the interior of the shell 301 through the conveying pipe 303. Under the action of the bag filter 304, the dust and particulate matter in the flue gas can be removed, and the impurities and particles are discharged through the bottom of the shell 301. The flue gas enters the interior of the deacidification mechanism 4 through the exhaust pipe 305 for deacidification. During the flue gas conveying process, the conditioner 9 is started and the conditioner 9 sprays an appropriate amount of water vapor or other additives into the flue gas, thereby optimizing the humidity and composition of the flue gas.

[0114] The effect achieved by the entire bag-type dust removal mechanism 3 is that the bag-type dust collector 304 can efficiently remove dust and particulate matter in the flue gas, with a removal rate of more than 99%. This not only protects subsequent equipment and prevents the catalytic deacidifier from reducing its activity due to particulate matter clogging its pores, but also prevents wear from damaging the structure of the catalytic deacidifier, thereby maintaining the long-term stability of the catalytic deacidifier, reducing the replacement frequency of the catalytic deacidifier, and reducing operating costs. The conditioner 9 can optimize the humidity and composition of the flue gas by spraying an appropriate amount of water vapor or other additives into the flue gas. For example, for some acidic gases with high viscosity, appropriately increasing the humidity can improve their dispersibility in the flue gas, making it easier for them to contact and react with the catalytic deacidifier; for specific acidic gas components, adding corresponding additives can promote the chemical reaction, significantly improve the deacidification efficiency, and enhance the system's adaptability to flue gases with different components.

[0115] like Figure 1 , Figure 2 and Figure 3 As shown, the deacidification mechanism 4 includes a cylinder 401, the bottom of the cylinder 401 is fixedly connected to a base frame 6, the bottom of the base frame 6 is fixedly connected to the bottom plate 1, the bottom of one side of the cylinder 401 is connected to a smoke exhaust pipe 7, one side of the cylinder 401 is connected to the smoke exhaust pipe 305, a rotating tube 402 is provided on the top of the cylinder 401, a first pulley 403 is fixedly connected to the surface of the rotating tube 402, a mounting frame 404 is fixedly connected to one side of the cylinder 401, a second motor 405 is fixedly connected to the top of the mounting frame 404, and an output end of the second motor 405 is connected to the output end of the second motor 405. A second pulley 406 is fixedly connected, and the second pulley 406 is transmission-connected to the first pulley 403 through a belt. A second connecting pipe 407 is connected to the top of the rotating tube 402. The bottom of the rotating tube 402 passes through the top of the cylinder 401 and extends to the inner cavity of the cylinder 401. The surface of the rotating tube 402 is connected to a nozzle 408. A distribution plate 409 is fixedly connected to the surface of the rotating tube 402 and located below the nozzle 408. There are four distribution plates 409, and a flow channel 5 is opened on the surface of the distribution plate 409. The flow channel 5 is distributed in a circular shape.

[0116] The flue gas enters the interior of the cylinder 401 through the exhaust pipe 305, and is connected to the feeding device of the catalytic deacidification agent through the second connecting pipe 407 (in another embodiment, the feeding device can be set at any position outside the application system). The catalytic deacidification agent is transported to the nozzle 408 through the interior of the rotating tube 402, and is evenly sprayed on the surface of the distribution plate 409 through the nozzle 408. The second motor 405 is started by the controller, and the second motor 405 drives the second pulley 406 to rotate, and the second pulley 406 drives the first belt pulley through the belt The wheel 403 rotates, the first pulley 403 drives the rotating tube 402 to rotate, and the rotating tube 402 drives the distribution plate 409 and the nozzle 408 to rotate. During the rotation of the distribution plate 409, the catalytic deacidification agent can be evenly distributed in the tower, which greatly increases the contact area between the catalytic deacidification agent and the flue gas. Compared with the traditional single-layer structure, the multi-layer distribution plate 409 can effectively increase the contact area, ensuring that the flue gas can fully contact with the catalytic deacidification agent during transportation, thereby improving the reaction efficiency and removing the acid gas more fully.

[0117] The effect achieved by the entire deacidification mechanism 4 is that, by setting up the cylinder 401, using solid materials and reasonable structural design, it can withstand harsh conditions such as high temperature and high pressure. The multi-layer distribution plate 409 inside it is reasonably designed and is not prone to problems such as blockage and deformation, ensuring the long-term and stable deacidification reaction. Good sealing can effectively prevent flue gas leakage and ensure the safety of operators while avoiding pollution to the surrounding environment. The efficient thermal insulation performance reduces heat loss and maintains a stable temperature in the tower, which is conducive to the continuous deacidification reaction, reduces energy consumption, and improves the energy utilization efficiency of the system.

[0118] The working principle of the application system of the dry catalytic deacidification agent for removing flue gas of the present invention is:

[0119] 1. The flue gas enters the interior of the box body 201 through the interior of the smoke inlet pipe 202 at the bottom of one side of the box body 201. A fan is arranged on the top of the smoke inlet pipe 202. The flue gas is continuously input into the interior of the box body 201 under the action of the fan. By starting the circulation pump 205, the circulation pump 205 extracts the coolant in the cooling box 203 through the first connecting pipe 204, and transports it to the interior of the spray rack 207 through the circulation pipe 206. The coolant cools the flue gas through the nozzle at the bottom of the spray rack 207. At the same time, by starting the first motor 209, the first motor 209 drives the circular gear 210 to rotate, the circular gear 210 drives the fan gear 211 to rotate, the fan gear 211 drives the rotating rod 212 to rotate, and the rotating rod 212 drives the spray rack 207 to rotate, so that the spray angle of the spray rack 207 can be adjusted. During the rotation process, the contact area between the coolant and the flue gas is guaranteed, the cooling effect is improved, and the purpose of rapid cooling is achieved.

[0120] 2. The cooled flue gas enters the interior of the shell 301 through the conveying pipe 303. Under the action of the bag filter 304, the dust and particles in the flue gas can be removed, and the impurities and particles are discharged through the bottom of the shell 301. The flue gas enters the interior of the deacidification mechanism 4 through the exhaust pipe 305 for deacidification. During the flue gas conveying process, the conditioner 9 is started, and the conditioner 9 sprays an appropriate amount of water vapor or other additives into the flue gas, which can optimize the humidity and composition of the flue gas.

[0121] 3. Flue gas enters the interior of the cylinder 401 through the smoke exhaust pipe 305, and is connected to the feeding device of the catalytic deacidifying agent through the second connecting pipe 407. The catalytic deacidifying agent is transported to the nozzle 408 through the interior of the rotating tube 402, and is evenly sprayed on the surface of the distribution plate 409 through the nozzle 408. The second motor 405 is started by the controller, and the second motor 405 drives the second pulley 406 to rotate. The second pulley 406 drives the first pulley 403 to rotate through the belt, and the first pulley 403 drives the rotating tube 402 to rotate. The rotating tube 402 drives the distribution plate 409 and the nozzle 408 to rotate. During the rotation of the distribution plate 409, the catalytic deacidifying agent can be evenly distributed in the tower, which greatly increases the contact area between the catalytic deacidifying agent and the flue gas. Compared with the traditional single-layer structure, the multi-layer distribution plate 409 can effectively increase the contact area, ensuring that the flue gas can fully contact with the catalytic deacidifying agent during the transportation process, improving the reaction efficiency, and removing the acid gas more fully.

[0122] It is understood that those skilled in the art will readily come to other embodiments of the present invention after considering the specification and practicing the technical concepts disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art that are not disclosed by the present invention. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the following scope of rights.

[0123] It should be understood that the present invention is not limited to the precise structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the scope of the appended claims.

Claims

1. A method for preparing a dry catalytic deacidification agent for removing flue gas, which is used to prepare a dry catalytic deacidification agent for removing flue gas, wherein the dry catalytic deacidification agent for removing flue gas comprises, by mass percentage, 42.7% to 88% of high-specific surface calcium hydroxide, 1.0% to 10.0% of cobalt nitrate, and 11.0% to 49.0% of a composite oxide, wherein the specific surface area of ​​the high-specific surface calcium hydroxide is ≥40m 2 / g, the dry catalytic deacidification agent further includes an auxiliary agent, the auxiliary agent is potassium molybdate, the mass percentage of the auxiliary agent to the total mass of the dry catalytic deacidification agent is 2.0-5.0%, and the composite oxide is any one of magnesium oxide and titanium dioxide; The preparation method of the dry catalytic deacidification agent for removing flue gas comprises the following steps: Step S1: preparation of a catalytic deacidification agent precursor; Step S2: kneading and forming the catalytic deacidifying agent; Step S1 further includes step S11, wherein 42.7% to 88% of high-specific calcium hydroxide, 1.0% to 10.0% of cobalt nitrate and 2.0% to 5.0% of an additive are mixed into solution I according to mass percentage; wherein the high-specific calcium hydroxide is first placed in a certain amount of water and stirred for 5 minutes, and then the cobalt nitrate and the additive are added and stirred for 30 minutes; Step S1 further includes step S12, wherein an alkaline precipitant and water glass are prepared into solution II; specifically, the alkaline precipitant and water glass are weighed in a ratio of 1:1 by mass, and the alkaline precipitant in a ratio of 1:1 by mass is added to the water glass and stirred for 10 minutes; the alkaline precipitant is one or both of urea or ammonium bicarbonate solution; Step S13, adding solution I and solution II into a reactor in parallel and performing an aging reaction; and step S14, filtering the slurry after the aging reaction to obtain a filter cake, washing the filter cake with deionized water and drying it to obtain a catalytic deacidification agent precursor; Step S2 further includes step S21, adding a certain amount of catalytic deacidification agent precursor prepared in step S1, an appropriate amount of composite oxide and one or two of methyl cellulose and field sesbania powder, using dilute acid or silica sol as a binder, using a silane coupling agent as a molding aid, kneading for 10 to 60 minutes to form a mass, and then extruding it into a shape.

2. An application system of a dry catalytic deacidification agent, which uses the dry catalytic deacidification agent prepared according to the preparation method of claim 1 to remove flue gas, characterized in that: The application system of the dry catalytic deacidification agent comprises a base plate (1), a pretreatment device (2) is fixedly connected to one side of the base plate (1), a bag dust removal mechanism (3) is fixedly connected to the top of the base plate (1), and a deacidification mechanism (4) is fixedly connected to the other side of the base plate (1); The deacidification mechanism (4) comprises a cylinder (401), one side of the cylinder (401) is connected to the smoke exhaust pipe (305), a rotating tube (402) is provided on the top of the cylinder (401), a first pulley (403) is fixedly connected to the surface of the rotating tube (402), a mounting frame (404) is fixedly connected to one side of the cylinder (401), a second motor (405) is fixedly connected to the top of the mounting frame (404), and an output end of the second motor (405) is fixedly connected to the second pulley (403). The second pulley (406) is connected to the first pulley (403) through a belt, the top of the rotating tube (402) is connected to the second connecting tube (407), the bottom of the rotating tube (402) passes through the top of the cylinder (401) and extends to the inner cavity of the cylinder (401), the surface of the rotating tube (402) is connected to the nozzle (408), and the surface of the rotating tube (402) and below the nozzle (408) is fixedly connected to a distribution plate (409); The flue gas enters the interior of the cylinder (401) through the smoke exhaust pipe (305) and is connected to the feeding device of the catalytic deacidification agent through the second connecting pipe (407). The catalytic deacidification agent is transported to the nozzle through the interior of the rotating tube and is evenly sprayed on the surface of the distribution plate through the nozzle.

3. The application system according to claim 2, characterized in that: The pretreatment device (2) comprises a box body (201); the bottom of one side of the box body (201) is connected to a smoke inlet pipe (202); a cooling box (203) is fixedly connected to one side above the bottom plate (1) and located below the box body (201); one side of the cooling box (203) is connected to a first connecting pipe (204); one side of the first connecting pipe (204) is connected to a circulation pump (205); one side of the circulation pump (205) is connected to a circulation pipe (206); one side of the circulation pipe (206) passes through one side of the box body (201) and extends to the inner cavity of the box body (201).

4. The application system according to claim 3, characterized in that: The side of the circulation pipe (206) away from the circulation pump (205) is connected to the spray rack (207) through a hose, and a housing (208) is fixedly connected to the upper side of one side of the box body (201), and a first motor (209) is fixedly connected to one side of the housing (208).

5. The application system according to claim 4, characterized in that: The output end of the first motor (209) passes through the inner cavity of the housing (208) and is fixedly connected to a circular gear (210); the inner cavity of the housing (208) is movably connected to a sector gear (211) via a bearing.

6. The application system according to claim 5, characterized in that: The sector gear (211) meshes with the circular gear (210), a rotating rod (212) is fixedly connected to the surface of the sector gear (211), a side of the rotating rod (212) away from the sector gear (211) penetrates into the inner cavity of the box body (201), and one side of the rotating rod (212) is fixedly connected to the spray rack (207).

7. The application system according to claim 2, characterized in that: The bag dust removal mechanism (3) comprises a shell (301), the bottom of the shell (301) is fixedly connected to the bottom plate (1), the bottom of the shell (301) is connected to a cleaning bucket (302), the top of the shell (301) is connected to a delivery pipe (303), the side of the delivery pipe (303) away from the shell (301) is connected to the box (201), the inner cavity of the shell (301) is fixedly connected to a bag dust collector (304), and the top of one side of the shell (301) is connected to a smoke exhaust pipe (305).

8. The application system according to claim 2, characterized in that: The number of the distribution plates (409) is four, and the surface of the distribution plates (409) is provided with flow channels (5), and the flow channels (5) are distributed in a circumferential manner; the bottom of the cylinder (401) is fixedly connected to a base frame (6), the bottom of the base frame (6) is fixedly connected to the bottom plate (1), and the bottom of one side of the cylinder (401) is connected to a smoke exhaust pipe (7).

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