Preparation method of catalyst for CO oxidation removal of sintering flue gas

Abstract

The invention relates to the technical field of CO oxidation removal catalysts, in particular to a preparation method of a sintering flue gas CO oxidation removal catalyst, which comprises the following specific steps: S1, pre-cleaning, S2, first drying, S3, dipping modification, S4, second drying, S5, ultrasonic coating, and S6, third drying and calcining. According to the invention, the catalytic active component is loaded on the molded inert surface carrier through an ultrasonic technology so as to give full play to the high specific surface area, sulfur resistance and water resistance; according to the technology, the removal efficiency of CO in the flue gas is improved. Besides, a synergistic effect is generated between the catalytic active component and the active component of the original molded inert carrier, so that the sulfur resistance and the water resistance of the catalyst are enhanced, the performance of the catalyst in the aspect of CO removal is improved, and the reaction temperature range of the catalyst is widened at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of CO oxidation removal catalysts, and in particular to a method for preparing a CO oxidation removal catalyst for sintering flue gas. Background Art

[0002] With the continuous advancement of air pollution prevention and control in my country, nitrogen oxides (NO x ) and carbon monoxide (CO) have been effectively controlled, and the environmental quality has improved accordingly. CO is a major air pollutant. It is very easy to combine with hemoglobin in the blood, which carries oxygen, and can cause hypoxia damage to humans or animals even at low concentrations. Therefore, reducing CO emissions has become an important issue that the government and enterprises are paying more and more attention to. The sintering flue gas in the steel industry is CO and NO x One of the main sources of pollution and carbon reduction, effectively controlling CO and NO x Emissions are crucial to continuously improving the quality of the atmospheric environment.

[0003] Patent CN104785246A discloses a supported low-temperature SCR catalyst, which uses TiO2 as a carrier and at least carries Mn-Ce-MO composite oxides of active components Mn and Ce. x / TiO2, wherein M represents one or more elements of Fe, Co, Cu, Cr, Zr, and Al. The catalyst is suitable for SCR catalysis and has poor water resistance and sulfur resistance.

[0004] Patent CN114160186A discloses a catalyst for simultaneously removing nitrogen oxides and carbon monoxide. The catalyst uses an acid-modified microporous or mesoporous material as a carrier, and the carrier is loaded with an active component. The active component includes any one or a combination of at least two of copper, manganese, vanadium, cerium, niobium, cobalt or iron oxides. The catalyst has poor catalytic performance for carbon monoxide at low temperatures, and poor water resistance and sulfur resistance.

[0005] Patent CN102921431A discloses a catalyst for the oxidation removal of carbon monoxide in hydrogen and a preparation method thereof. The catalyst is a salt solution of a soluble platinum salt and an auxiliary agent, which is loaded on a carrier by impregnation or coprecipitation, and is dried and calcined, reduced with hydrazine hydrate at room temperature, and then dried. However, the existing carrier has more or less impurities adhered to its surface, and the impurities will cause adverse effects during impregnation modification or precipitation, thereby ultimately affecting the effect of the catalyst on CO removal.

[0006] In summary, existing catalysts have limitations in the oxidation removal of carbon monoxide, so in order to solve the above problems, it is particularly important to design a preparation method for a catalyst for the oxidation removal of CO from sintering flue gas. Summary of the invention

[0007] In order to solve the above problems, the present invention designs a preparation method for a catalyst for oxidative removal of CO from sintered flue gas. The catalytic active components are loaded on a shaped inert surface carrier by ultrasonic technology to give full play to its high specific surface area and anti-sulfur and anti-water properties; this technology improves the removal efficiency of CO in flue gas. In addition, a synergistic effect is generated between the catalytic active components and the active components of the original shaped inert carrier, which not only enhances the catalyst's anti-sulfur and anti-water properties, but also improves the catalyst's performance in CO removal, while broadening its reaction temperature range; in general, the catalyst not only has excellent performance, but also has outstanding cost-effectiveness.

[0008] In order to solve the above technical problems, the present invention provides a method for preparing a catalyst for oxidative removal of CO from sintering flue gas, which specifically comprises the following steps:

[0009] S1: Pre-cleaning: The selected inert carrier is placed in a hanging frame with filter holes on the sides and bottom, and then the hanging frame with the inert carrier is placed in an ultrasonic cleaning tank by a mechanical arm for cleaning to remove impurities on the surface of the inert carrier;

[0010] S2: First drying: The inert carrier after cleaning in step S1 is sent into a first drying oven by a mechanical arm using a hanging frame, and the inert carrier is dried in the first drying oven;

[0011] S3: Impregnation modification: The dried inert carrier is placed into an impregnation box by a mechanical arm using a hanging frame, and the inert carrier is impregnated and modified in the impregnation box to form a catalyst;

[0012] S4: Second drying: The catalyst impregnated and modified in step S3 is sent into the second drying oven by a mechanical arm using a hanging frame, and the catalyst is dried for a second time in the second drying oven at 80°C in an air atmosphere for 5-8h;

[0013] S5: Ultrasonic coating: The catalyst after the second drying is taken out from the hanging frame and sent into an ultrasonic dipping coating machine to immerse the catalyst in the noble metal catalytic active solution. The ultrasonic dipping is carried out at 50-80°C for 1-2 hours. The noble metal catalytic active solution is evenly coated on the catalyst surface by ultrasonic waves. The power of ultrasonic radiation is 100-600W and the frequency is 25kHz.

[0014] S6: Third drying and calcination: The catalyst processed in step S5 is sent to an oven for a third drying, and then sent to a calcining furnace for calcination. It is calcined at 400-600° C. for 8 hours in an air atmosphere to obtain a CO oxidation removal catalyst.

[0015] Further: the inert carrier in step S1 includes one of aluminum oxide, cordierite, activated carbon, and molecular sieve, and the shape of the inert carrier is honeycomb or granular.

[0016] Further: the mechanical arm in step S1 is composed of a mounting seat, a lifting electric cylinder and a lifting clamping and positioning assembly. The mounting seat is connected to the bottom of the upper support seat through a translation mechanism, the lifting electric cylinder is fixed to the bottom of the mounting seat, and the lifting clamping and positioning assembly is connected to the output shaft end of the lifting electric cylinder. The lifting clamping and positioning assembly is used to sequentially transport the hanging frame to the ultrasonic cleaning tank, the first drying box, the immersion box and the second drying box through the translation mechanism. The ultrasonic cleaning tank is located between the first temporary placement seat and the second temporary placement seat. The first drying box is located between the second temporary seat and the third temporary seat, the impregnation box is located between the third temporary seat and the fourth temporary seat, the second drying box is located between the fourth temporary seat and the drying chamber, the drying chamber is connected to the second drying box, the first drying box, the impregnation box and the second drying box are all movably connected with sealing covers on the top, the left and right ends of the sealing cover are provided with guide strips connected thereto, and the second temporary seat, the third temporary seat, the fourth temporary seat and the side walls of the upper end of the drying chamber are provided with guide grooves at positions relative to the guide strips.

[0017] Furthermore: the lifting clamping and positioning assembly is composed of two mounting cylinders, three connecting rods, a hook-shaped lifting rod, a positioning plate, a pushing plate, a pushing electric cylinder and a telescopic electric cylinder. The two mounting cylinders are arranged in parallel and horizontally, and the three connecting rods are fixed between the two mounting cylinders in sequence from left to right. The output shaft end of the lifting electric cylinder is connected to the top of the connecting rod in the middle. A telescopic electric cylinder is installed in each of the two ends of the mounting cylinder, and the output shaft end of the telescopic electric cylinder is connected to one end of the hook-shaped lifting rod extending into the end of the mounting cylinder, and the end of the hook-shaped lifting rod away from the telescopic electric cylinder is hook-shaped, and the positioning plate is arranged at the bottom of the rod body of the hook-shaped lifting rod extending out of the mounting cylinder, and the positioning plate is vertically arranged to the rod body of the hook-shaped lifting rod, and the pushing plate is installed on the rod body of the hook-shaped lifting rod extending out of the mounting cylinder, and the output shaft end of the pushing plate passes through the hook-shaped lifting rod and is connected to the pushing plate, and the pushing plate and the rod body of the hook-shaped lifting rod are parallel to each other.

[0018] Furthermore: the translation mechanism includes an upper support seat, a mounting side plate, a servo motor, a guide rod and a lead screw. The upper support seat is fixed to the ultrasonic cleaning tank, the first drying box, the immersion box and the second drying box through a side bracket. A mounting side plate is vertically fixed to the bottom of the left and right ends of the upper support seat. The lead screw is horizontally rotatably connected between the two mounting side plates and one end of the lead screw is connected to a servo motor fixed on a mounting side plate. The guide rod is horizontally fixed between the two mounting side plates. A threaded through hole and a guide through hole are respectively opened between the left and right ends of the mounting seat relative to the positions of the lead screw and the guide rod. The mounting seat is connected to the lead screw through the threaded through hole, and the guide rod passes through the mounting seat along the guide through hole.

[0019] Furthermore: an auxiliary support plate is installed in the lower end of the first drying box, and the auxiliary support plate divides the internal space of the first drying box into two spaces, the upper one is a drying chamber, and the lower one is a recovery chamber, the drying chamber is connected to the recovery chamber through a number of through holes opened on the first drying box, a rotating support seat is fixed on the auxiliary support plate, a rotating seat is rotatably connected to the top of the rotating support seat, the upper end of the rotating seat extends out of the rotating support seat, an outer gear ring is fixed on the outer wall of the rotating seat extending out of the rotating support seat, the outer gear ring is meshed with a rotating drive gear, the rotating drive gear is fixed on the output shaft of the rotating drive motor, the rotating drive motor is installed on the auxiliary support plate, four mounting frames are evenly fixed on the top of the rotating seat, and the four mounting frames are The frames are arranged opposite to each other in pairs, and a clamping electric cylinder is installed in the opposite side of the mounting frame, the output shaft end of the clamping electric cylinder is connected to the clamping end head, and the hanging frame is fixed to the top of the rotating seat through four clamping ends in front, back, left and right. An air heating chamber is opened in the upper end of the second temporary placement seat, and an electric heating tube and a first temperature sensor are installed in the air heating chamber. An air outlet is opened in the air heating chamber on the side facing the first drying box, and a hot air collection chamber is opened in the upper end of the third temporary placement seat, and an air inlet is opened in the hot air collection chamber on the side facing the first drying box. Oblique flow guide holes are opened on the left and right sides of the first drying box relative to the positions of the air outlet and the air inlet, and the lower end of the flow guide hole is connected to the drying chamber, and the hot air collection chamber is also connected to the air heating chamber through a circulation pipe, and a circulation pump is installed on the circulation pipe.

[0020] Furthermore: two parallel slide rails are arranged at the bottom of the drying chamber and the second drying box, a door guide frame is arranged at the right end of the drying chamber, a door is connected to the door guide frame for sliding up and down, the door is connected to the door switch electric cylinder installed on the top of the drying chamber, the right end of the slide rail extends out of the drying chamber, a through groove is arranged at the bottom of the door relative to the position of the slide rail, a groove is arranged on the side of the fourth temporary placement seat facing the second drying box, the groove is connected to the second drying box, the groove of the fourth temporary placement seat is connected to the translation push plate through the translation push electric cylinder, a slider matching the slide rail is arranged at the bottom of the hanging frame, the hanging frame in the second drying box enters the drying chamber along the slide rail through the push of the translation push plate, a heating resistor wire and a second temperature sensor are installed in the second drying box and the drying chamber.

[0021] Furthermore: the active components of the impregnation solution in the impregnation box include one or a combination of V, Mo, W, Ce, Co, Mn, and Fe, and the amount of active components added to the inert carrier after the catalyst is formed is 2-5wt% by weight.

[0022] Furthermore: the noble metal catalytic active solution components in step S5 include one or a combination of platinum, palladium, rhodium, copper, and cerium, and the loading amount of the noble metal coated on the catalyst carrier is 0.01-1% of the weight of the carrier.

[0023] Further: the ultrasonic dipping coating machine in step S5 is placed in a water bath, a third temperature sensor is arranged in the water bath, a pressure switch valve connected to the water bath is installed on the side wall of the lower end of the water bath, the pressure switch valve is connected to the water inlet of the three-way electromagnetic control valve, a first water outlet of the three-way electromagnetic control valve is connected to the reflux pump installed on the side wall of the heating water tank through a first diversion pipe, the first diversion pipe is connected to the heating water tank through the reflux pump, a water supply pipe is also connected to the upper side wall of the heating water tank, the heating water tank is connected to the water pump installed on the outer wall of the upper end of the water bath through a delivery water pipe, the delivery water pipe is connected to the water bath through the water pump, and a fourth temperature sensor is installed in the three-way electromagnetic control valve. A temperature sensor is installed in the heating water tank, and its second water outlet is connected with the water delivery pipe through the second guide pipe. A fifth temperature sensor is installed in the heating water tank. The pressure switch valve is a one-way valve, which is specifically composed of an outer valve body, an inner valve body, a valve core and a spring. The open end of the outer valve body is installed on the outer wall of the water bath and is connected with it, and the other end of the outer valve body is fixed on the outer wall of the inner valve body. One end of the inner valve body in the outer valve body is sealed, and the other end of the inner valve body extends out of the outer valve body and is connected to the water inlet of the three-way electromagnetic control valve. The valve core is annular, and the valve core is piston-connected between the outer wall of the inner valve body and the outer wall of the outer valve body and is connected to the outer valve body through a spring. An overflow hole is opened on the side wall of the inner valve body in the outer valve body, and the overflow hole is sealed by the valve core.

[0024] After adopting the above structure, the present invention is composed of a catalyst carrier and a metal catalyst loaded thereon; the function of the carrier is to increase the surface area and active sites of the catalyst, while the metal particles are used to catalyze the removal of carbon monoxide in the flue gas to generate environmentally friendly compounds. This catalyst uses precious metals to reduce the activation energy of carbon monoxide oxidation, thereby playing a catalytic oxidation role; since the selected shaped inert catalyst carrier and precious metals have high acid stability, the carbon monoxide catalyst has high sulfur resistance and water resistance, and therefore has high catalytic stability in sintering flue gas purification. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] Figure 1 This is the usage status diagram of the robotic arm.

[0027] Figure 2 This is a structural diagram of the lifting clamping and positioning assembly.

[0028] Figure 3 This is a top view of the internal structure of the second drying box.

[0029] Figure 4 This is a diagram of the ultrasonic dipping coating machine in use.

[0030] Figure 5 This is the internal structure diagram of the pressure switch valve.

[0031] In the figure: 1 is an upper support seat, 2 is a first temporary seat, 3 is a second temporary seat, 4 is a third temporary seat, 5 is a fourth temporary seat, 6 is a drying chamber, 7 is an ultrasonic cleaning tank, 8 is a first drying box, 9 is an immersion box, 10 is a second drying box, 11 is a guide rod, 12 is a lead screw, 13 is a mounting side plate, 14 is a servo motor, 15 is a mounting seat, 16 is a lifting cylinder, 17 is a hanging frame, 18 is a sealing cover, 19 is an ultrasonic immersion coating machine, 20 is a water bath, 21-1 is a mounting cylinder, 21-2 is three connecting rods, 21-3 is a hook-shaped lifting rod, 21-4 is a positioning plate 21-4, 21-5 is a push electric Cylinder, 21-6 is a push plate, 22 is a door switch electric cylinder, 23 is a door, 24 is a slide rail, 25 is an auxiliary support plate, 26 is a rotating support seat, 27 is a swivel seat, 28 is a mounting frame, 29 is a clamping end, 30 is a rotating drive gear, 31 is a circulation pipeline, 32 is a side bracket, 33 is a pressure switch valve, 34 is a three-way electromagnetic control valve, 35 is a heating water tank, 36 is a first diversion pipeline, 37 is a reflux pump, 38 is a water supply pipeline, 39 is a water pump, 40 is a water delivery pipe, 41 is a second diversion pipeline, 42 is an inner valve body, 43 is an outer valve body, 44 is a valve core, 45 is a spring, and 46 is an overflow hole. DETAILED DESCRIPTION

[0032] The present invention provides a method for preparing a catalyst for oxidative removal of CO from sintering flue gas, which specifically comprises the following steps:

[0033] S1: Pre-cleaning: The selected inert carrier is placed in a hanging frame with filter holes on the sides and bottom, and then the hanging frame with the inert carrier is placed in an ultrasonic cleaning tank by a mechanical arm for cleaning to remove impurities on the surface of the inert carrier;

[0034] S2: First drying: The inert carrier after cleaning in step S1 is sent into a first drying oven by a mechanical arm using a hanging frame, and the inert carrier is dried in the first drying oven;

[0035] S3: Impregnation modification: The dried inert carrier is placed into an impregnation box by a mechanical arm using a hanging frame, and the inert carrier is impregnated and modified in the impregnation box to form a catalyst;

[0036] S4: Second drying: The catalyst impregnated and modified in step S3 is sent into the second drying oven by a mechanical arm using a hanging frame, and the catalyst is dried for a second time in the second drying oven at 80°C in an air atmosphere for 5-8h;

[0037] S5: Ultrasonic coating: The catalyst after the second drying is taken out from the hanging frame and sent into an ultrasonic dipping coating machine to immerse the catalyst in the noble metal catalytic active solution. The ultrasonic dipping is carried out at 50-80°C for 1-2 hours. The noble metal catalytic active solution is evenly coated on the catalyst surface by ultrasonic waves. The power of ultrasonic radiation is 100-600W and the frequency is 25kHz.

[0038] S6: Third drying and calcination: The catalyst processed in step S5 is sent to an oven for a third drying, and then sent to a calcining furnace for calcination. It is calcined at 400-600° C. for 8 hours in an air atmosphere to obtain a CO oxidation removal catalyst.

[0039] After the present invention adopts the above method, the catalyst prepared by the present invention is composed of a catalyst carrier and a metal catalyst loaded thereon; the function of the carrier is to increase the surface area and active sites of the catalyst, while the metal particles are used to catalyze the removal of carbon monoxide in flue gas to generate environmentally friendly compounds. This catalyst uses precious metals to reduce the activation energy of carbon monoxide oxidation, thereby playing a catalytic oxidation role; since the selected shaped inert catalyst carrier and metals such as precious metals have high acid stability, the carbon monoxide catalyst has high sulfur resistance and water resistance, and therefore has high catalytic stability in sintering flue gas purification.

[0040] The inert carrier in the above step S1 includes one of aluminum oxide, cordierite, activated carbon, and molecular sieve, and the shape of the inert carrier is honeycomb or granular.

[0041] like Figure 1 The mechanical arm in step S1 is composed of a mounting seat 15, a lifting electric cylinder 16 and a lifting clamping and positioning assembly. The mounting seat 15 is connected to the bottom of the upper support seat 1 through a translation mechanism, and the lifting electric cylinder 16 is fixed to the bottom of the mounting seat 15. The lifting clamping and positioning assembly is connected to the output shaft end of the lifting electric cylinder 16. The lifting frame 17 is transported to the ultrasonic cleaning tank 7, the first drying box 8, the dipping box 9 and the second drying box 10 in sequence through the translation mechanism using the lifting clamping and positioning assembly. The ultrasonic cleaning tank 7 is located between the first temporary placement seat 2 and the second temporary placement seat 3. The first drying box 10 is located between the first temporary placement seat 2 and the second temporary placement seat 3. The box 8 is located between the second temporary seat 3 and the third temporary seat 4, the impregnation box 9 is located between the third temporary seat 4 and the fourth temporary seat 5, the second drying box 10 is located between the fourth temporary seat 5 and the drying chamber 6, the drying chamber 6 is connected to the second drying box 10, the first drying box 8, the impregnation box 9 and the second drying box 10 are all movably connected with a sealing cover 18 at the top, and the left and right ends of the sealing cover 18 are provided with guide strips connected thereto, and the second temporary seat 3, the third temporary seat 4, the fourth temporary seat 5 and the side wall of the upper end of the drying chamber 6 are provided with guide grooves relative to the guide strips. The present invention can automatically complete pre-cleaning, impregnation modification and double drying after adopting the above structure, and the production efficiency of the catalyst is greatly improved by this structure; and the present invention removes impurities on the surface of the carrier by ultrasonic cleaning to prevent impurities from causing adverse effects during impregnation, thereby increasing practical performance.

[0042] like Figure 2The lifting clamping and positioning assembly shown is composed of two mounting cylinders 21-1, three connecting rods 21-2, a hook-shaped lifting rod 21-3, a positioning plate 21-4, a pushing plate 21-6, a pushing electric cylinder 21-5 and a telescopic electric cylinder. The two mounting cylinders 21-1 are arranged horizontally in parallel, and the three connecting rods 21-2 are fixed between the two mounting cylinders 21-1 in sequence from left to right. The shaft end of the lifting electric cylinder 16 is connected to the top of the connecting rod 21-2 located in the middle. A telescopic electric cylinder is installed at each end of the mounting cylinder 21-1. The end is connected to one end of a hook-shaped lifting rod extending into the end of the mounting cylinder, and the end of the hook-shaped lifting rod away from the telescopic electric cylinder is hook-shaped. The positioning plate 21-4 is arranged at the bottom of the rod body of the hook-shaped lifting rod extending out of the mounting cylinder 21-1, and the positioning plate 21-4 is vertically arranged to the rod body of the hook-shaped lifting rod. The pushing plate 21-6 is installed on the rod body of the hook-shaped lifting rod extending out of the mounting cylinder 21-1, and the shaft end of the pushing plate 21-6 passes through the hook-shaped lifting rod and is connected to the pushing plate 21-6, and the pushing plate 21-6 and the rod body of the hook-shaped lifting rod are parallel to each other. When lifting the hanging frame, first use the lifting electric cylinder to lower the lifting clamping positioning assembly, start the telescopic electric cylinder to insert the hook-shaped lifting rod under the lifting handle on the hanging frame, first use the positioning plate and the end of the hook-shaped lifting rod to position the hanging frame left and right, and then start the pushing electric cylinder to use the pushing plates on the front and rear sides to position the hanging frame front and back. The present invention adopts the above structure to effectively ensure the accurate conveying position of the hanging frame, and no unnecessary shaking will occur during the conveying process, thereby increasing practical performance.

[0043] like Figure 1 The translation mechanism shown includes an upper support seat 1, a mounting side plate 13, a servo motor 14, a guide rod 11 and a lead screw 12. The upper support seat 1 is fixed directly above the ultrasonic cleaning tank 7, the first drying box 8, the immersion box 9 and the second drying box 10 through a side bracket 32. A mounting side plate 13 is vertically fixed to the bottom of the left and right ends of the upper support seat 1. The lead screw 12 is horizontally rotatably connected between the two mounting side plates 13 and one end of the lead screw 12 is connected to the servo motor 14 fixed on a mounting side plate. The guide rod 11 is horizontally fixed between the two mounting side plates 13. A threaded through hole and a guide through hole are respectively opened between the left and right ends of the mounting seat 15 at positions relative to the lead screw 12 and the guide rod 11. The mounting seat 15 is connected to the lead screw 12 through a threaded through hole, and the guide rod 11 passes through the mounting seat 15 along the guide through hole.

[0044] like Figure 3An auxiliary support plate 25 is installed in the lower end of the first drying box 8 shown in the figure. The auxiliary support plate 25 divides the internal space of the first drying box 8 into two spaces, one above and one below. The drying chamber is located at the upper part, and the recovery chamber is located at the lower part. The drying chamber is connected to the recovery chamber through a number of through holes opened on the first drying box 8. A rotating support seat 26 is fixed on the auxiliary support plate 25. A rotating seat 27 is rotatably connected to the top of the rotating support seat 26. The upper end of the rotating seat 27 extends out of the rotating support seat 26. An outer gear ring is fixed on the outer wall of the rotating seat 27 extending out of the rotating support seat 26. The outer gear ring is meshed with a rotating drive gear 30. The rotating drive gear 30 is fixed on the output shaft of the rotating drive motor. The rotating drive motor is installed on the auxiliary support plate 25. Four mounting frames 2 are evenly fixed on the top of the rotating seat 27. 8. Four mounting frames 28 are arranged opposite to each other in pairs, and a clamping electric cylinder is installed in the opposite side of the mounting frame, and the output shaft end of the clamping electric cylinder is connected to the clamping end head 29. The hanging frame 17 is fixed to the top of the rotating seat through four clamping ends 29 in front, back, left and right. An air heating chamber is opened in the upper end of the second temporary placement seat 3, and an electric heating tube and a first temperature sensor are installed in the air heating chamber. An air outlet is opened in the air heating chamber on the side facing the first drying box. A hot air collection chamber is opened in the upper end of the third temporary placement seat 4, and an air inlet is opened in the hot air collection chamber on the side facing the first drying box. Oblique flow guide holes are opened on the left and right sides of the first drying box 8 relative to the positions of the air outlet and the air inlet, and the lower end of the flow guide hole is connected to the drying chamber. The hot air collection chamber is also connected to the air heating chamber through a circulation pipe 31, and a circulation pump is installed on the circulation pipe 31. The present invention dries the pre-cleaned carrier by means of rotation and air heating, thereby greatly improving the drying efficiency; and the present invention can also recover and collect the cleaning water centrifugally thrown out, thereby playing a role in saving resources and reducing costs.

[0045] like Figure 1The bottom of the drying chamber 6 and the second drying box 10 shown are provided with two parallel slide rails 24, the right end of the drying chamber 6 is provided with a box door guide frame, and the box door 23 is connected to the box door guide frame for sliding up and down, the box door 23 is connected to the box door switch electric cylinder 22 installed on the top of the drying chamber 6, the right end of the slide rail 24 extends out of the drying chamber 6, and a through groove is provided at the bottom of the box door 23 relative to the position of the slide rail 24, the fourth temporary seat 5 is provided with a groove on the side facing the second drying box 10, and the groove is connected to the second drying box 10, the groove of the fourth temporary seat 5 is connected to the translation push plate through the translation push electric cylinder, and a slider matching the slide rail 24 is provided at the bottom of the hanging frame 17, and the hanging frame in the second drying box 10 enters the drying chamber 6 along the slide rail 24 through the push of the translation push plate, and the second drying box 10 and the drying chamber 6 are both installed with a heating resistor wire and a second temperature sensor. After the hanging frame with the impregnated carrier is placed in the second drying box, it is dried by the high-temperature air in the second drying box. When a new hanging frame needs to be placed, the translation push electric cylinder is started to use the translation push plate to push the original hanging frame into the drying room to continue drying. When two or more hanging frames enter the drying room, the newly entered hanging frame will push the hanging frame originally in the drying room to move to the right along the slide rail. When the third hanging frame is to enter the drying room, the box door is opened, and the hanging frame on the far right will be automatically pushed out of the drying room. At this time, the drying time of the hanging frame meets the requirements. The present invention adopts the above structure to continuously perform pre-cleaning, impregnation and drying without waiting, which plays a role in improving production efficiency.

[0046] The active components of the impregnation solution in the impregnation box include one or a combination of V, Mo, W, Ce, Co, Mn, and Fe, and the amount of active components added to the inert carrier after the catalyst is formed is 2-5wt% by weight.

[0047] The noble metal catalytic active solution in step S5 includes one or a combination of platinum, palladium, rhodium, copper and cerium. The loading amount of the noble metal coated on the catalyst carrier is 0.01-1% of the weight of the carrier.

[0048] like Figure 4 and Figure 5The ultrasonic dipping coating machine 19 in step S5 is placed in a water bath 20, a third temperature sensor is arranged in the water bath 20, a pressure switch valve 33 connected thereto is installed on the side wall of the lower end of the water bath, the pressure switch valve is connected to the water inlet of the three-way electromagnetic control valve 34, a first water outlet of the three-way electromagnetic control valve 34 is connected to a reflux pump 37 installed on the side wall of the heating water tank 35 through a first diversion pipe 36, the first diversion pipe is connected to the heating water tank 35 through the reflux pump 37, a water supply pipe 38 is also connected to the upper side wall of the heating water tank 35, the heating water tank 35 is connected to a water pump 39 installed on the outer wall of the upper end of the water bath 20 through a delivery water pipe 40, the delivery water pipe 40 is connected to the water bath 20 through the water pump 39, a fourth temperature sensor is installed in the three-way electromagnetic control valve 34 and Its second water outlet is connected with the water delivery pipe 40 through the second guide pipe 41, and a fifth temperature sensor is installed in the heating water tank 35. The pressure switch valve is a one-way valve, which is specifically composed of an outer valve body 43, an inner valve body 42, a valve core 44 and a spring 45. The open end of the outer valve body 43 is installed on the outer wall of the water bath 20 and is connected thereto, and the other end of the outer valve body 43 is fixed on the outer wall of the inner valve body 42. One end of the inner valve body 42 in the outer valve body is sealed, and the other end of the inner valve body extends out of the outer valve body and is connected to the water inlet of the three-way electromagnetic control valve 34. The valve core 44 is annular, and the valve core 44 is piston-connected between the outer wall of the inner valve body 42 and the inner wall of the outer valve body 43 and is connected to the outer valve body 43 through a spring 45. An overflow hole 46 is opened on the side wall of the inner valve body 42 in the outer valve body 43, and the overflow hole 46 is sealed by the valve core 44. The present invention ensures that the temperature of the carrier meets the requirements during ultrasonic impregnation by means of water bath heating, and can continuously circulate water through the design of the pressure switch valve, so that the water bath temperature will not change significantly with time, thereby increasing practical performance.

[0049] Implementation Case 1:

[0050] 1. Catalyst preparation: Select a molded honeycomb cordierite with a pore number of 50 and a size of 150*150*400mm as a carrier. The amount of active component V impregnated in the molded cordierite carrier is 5wt%, and the weight of the catalyst carrier is 2500g. Add 25g of precious metal palladium to the catalytic active component solution and mix thoroughly. Put the molded honeycomb carrier into the catalytic active component solution at 60°C and ultrasonically impregnate it for 2h under the conditions of ultrasonic power of 600W and frequency of 25kHz. After impregnation, the catalyst is dried for 8h in an air atmosphere at 80°C, and then calcined at 500°C for 8h in an air atmosphere to obtain a CO removal catalyst.

[0051] 2. Activity test of the catalyst: The CO catalyst prepared above was placed in a fixed bed reactor. The simulated flue gas consisted of CO, O2, N2, and H2O, where the H2O concentration was 10%, the CO concentration was 10000ppm, and the air velocity was designed to be 20000h -1 The reaction temperature is 180-350°C, and the reaction tail gas is monitored online with an infrared detector. Under this reaction condition, the CO conversion rate is always maintained above 90%.

[0052] Implementation Case 2:

[0053] 1. Catalyst preparation: Select the molded aluminum oxide pellets as the carrier, and the surface of the molded aluminum oxide pellets is impregnated with active components with an addition amount of 2% V and an addition amount of 3% Mo, and the catalyst weight is 1500g. Add 7.5g of precious metal platinum to the catalytic active component solution and mix thoroughly, put the molded catalyst carrier into the catalytic active component solution at 70°C, and ultrasonically impregnate for 2h under the conditions of ultrasonic radiation power of 100W and frequency of 25kHz. After impregnation, the catalyst is dried for 5h in an air atmosphere at 80°C, and then calcined at 400°C for 8h in an air atmosphere to obtain a CO removal catalyst.

[0054] 2. Catalyst activity test: The CO catalyst prepared above was placed in a fixed bed reactor. The simulated flue gas consisted of CO, O2, N2, and H2O, where the H2O concentration was 10%, the CO concentration was 10000ppm, and the air velocity was designed to be 20000h -1 The reaction temperature is 180-350°C, and the reaction tail gas is monitored online with an infrared detector. Under this reaction condition, the CO conversion rate is always maintained above 85%.

[0055] Implementation Case 3:

[0056] 1. Catalyst preparation: Select the molded molecular sieve as the carrier, the active component impregnated in the molded inert carrier is 2% of V and 3% of Ce, and the catalyst weight is 1800g. Add 10g of precious metal platinum to the catalytic active component solution and mix thoroughly, put the molded catalyst into the catalytic active component solution at 60°C, and ultrasonically impregnate for 1h under the conditions of ultrasonic radiation power of 400W and frequency of 25kHz. After impregnation, the catalyst is dried for 5h in an air atmosphere at 80°C, and then calcined at 600°C for 8h in an air atmosphere to obtain a CO removal catalyst.

[0057] 2. Catalyst activity test: The CO catalyst prepared above was placed in a fixed bed reactor. The simulated flue gas consisted of CO, O2, N2, and H2O, where the H2O concentration was 10%, the CO concentration was 10000ppm, and the air velocity was designed to be 20000h -1The reaction temperature is 180-350°C, and the reaction tail gas is monitored online with an infrared detector. Under this reaction condition, the CO conversion rate is always maintained above 88%.

[0058] The present invention innovatively utilizes the existing shaped inert catalyst, gives full play to the high specific surface area and sulfur and water resistance of the shaped inert carrier catalyst, prepares a high-efficiency catalyst by loading metal active components in batches, and improves the efficiency of removing CO from flue gas. At the same time, the noble metal catalyst and the original carrier surface active components can produce a synergistic promotion effect, which is not only beneficial to the sulfur and water resistance of the catalyst, but also improves the performance of the catalyst in removing CO and broadens the reaction temperature of the catalyst. The prepared catalyst has the characteristics of excellent performance and low cost.

[0059] The above are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a catalyst for oxidative removal of CO from sintering flue gas, characterized in that: The specific steps include: S1: Pre-cleaning: The selected inert carrier is placed in a hanging frame with filter holes on the sides and bottom, and then the hanging frame with the inert carrier is placed in an ultrasonic cleaning tank by a mechanical arm for cleaning to remove impurities on the surface of the inert carrier; S2: First drying: The inert carrier after cleaning in step S1 is sent into a first drying oven by a mechanical arm using a hanging frame, and the inert carrier is dried in the first drying oven; S3: Impregnation modification: The dried inert carrier is placed into an impregnation box by a mechanical arm using a hanging frame, and the inert carrier is impregnated and modified in the impregnation box to form a catalyst; S4: Second drying: The catalyst impregnated and modified in step S3 is sent into the second drying oven by a mechanical arm using a hanging frame, and the catalyst is dried for a second time in the second drying oven at 80°C in an air atmosphere for 5-8h; S5: Ultrasonic coating: The catalyst after the second drying is taken out from the hanging frame and sent into an ultrasonic dipping coating machine to immerse the catalyst in the noble metal catalytic active solution. The ultrasonic dipping is carried out at 50-80°C for 1-2 hours. The noble metal catalytic active solution is evenly coated on the catalyst surface by ultrasonic waves. The power of ultrasonic radiation is 100-600W and the frequency is 25kHz. S6: Third drying and calcination: The catalyst processed in step S5 is sent to an oven for a third drying, and then sent to a calcining furnace for calcination. It is calcined at 400-600° C. for 8 hours in an air atmosphere to obtain a CO oxidation removal catalyst.

2. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 1, characterized in that: The inert carrier in step S1 includes one of aluminum oxide, cordierite, activated carbon, and molecular sieve, and the inert carrier has a honeycomb or granular shape.

3. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 1, characterized in that: The mechanical arm in step S1 is composed of a mounting seat (15), a lifting electric cylinder (16) and a lifting clamping and positioning assembly. The mounting seat (15) is connected to the bottom of the upper support seat (1) through a translation mechanism. The lifting electric cylinder (16) is fixed to the bottom of the mounting seat (15). The lifting clamping and positioning assembly is connected to the output shaft end of the lifting electric cylinder (16). The lifting clamping and positioning assembly is used to sequentially transport the hanging frame (17) to the ultrasonic cleaning tank (7), the first drying box (8), the immersion box (9) and the second drying box (10) through the translation mechanism. The ultrasonic cleaning tank (7) is located between the first temporary storage seat (2) and the second temporary storage seat (3). The first drying box (8) is located The impregnation box (9) is located between the second temporary seat (3) and the third temporary seat (4), the impregnation box (9) is located between the third temporary seat (4) and the fourth temporary seat (5), the second drying box (10) is located between the fourth temporary seat (5) and the drying chamber (6), the drying chamber (6) is connected to the second drying box (10), the tops of the first drying box (8), the impregnation box (9) and the second drying box (10) are movably connected with a sealing cover (18), the left and right ends of the sealing cover (18) are provided with guide strips connected thereto, and the side walls of the second temporary seat (3), the third temporary seat (4), the fourth temporary seat (5) and the upper end of the drying chamber (6) are provided with guide grooves at positions relative to the guide strips.

4. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 3, characterized in that: The lifting clamping and positioning assembly is composed of two installation cylinders (21-1), three connecting rods (21-2), a hook-shaped lifting rod (21-3), a positioning plate (21-4), a pushing plate (21-6), a pushing electric cylinder (21-5) and a telescopic electric cylinder. The two installation cylinders (21-1) are arranged horizontally in parallel. The three connecting rods (21-2) are fixed in sequence from left to right between the two installation cylinders (21-1). The shaft end of the lifting electric cylinder (16) is connected to the top of the connecting rod (21-2) in the middle. A telescopic electric cylinder is installed at each end of the installation cylinder (21-1). The shaft end is connected to one end of a hook-shaped lifting rod extending into the end of the mounting cylinder, and the end of the hook-shaped lifting rod away from the telescopic electric cylinder is hook-shaped. The positioning plate (21-4) is arranged at the bottom of the rod body of the hook-shaped lifting rod extending out of the mounting cylinder (21-1), and the positioning plate (21-4) and the rod body of the hook-shaped lifting rod are arranged vertically. The pushing plate (21-6) is installed on the rod body of the hook-shaped lifting rod extending out of the mounting cylinder (21-1), and the shaft end of the pushing plate (21-6) passes through the hook-shaped lifting rod and is connected to the pushing plate (21-6), and the pushing plate (21-6) and the rod body of the hook-shaped lifting rod are parallel to each other.

5. The method for preparing a catalyst for sintering flue gas CO oxidation removal according to claim 3, characterized in that: The translation mechanism comprises an upper support seat (1), a mounting side plate (13), a servo motor (14), a guide rod (11) and a lead screw (12). The upper support seat (1) is fixed to the upper part of the ultrasonic cleaning tank (7), the first drying box (8), the immersion box (9) and the second drying box (10) through a side bracket (32). A mounting side plate (13) is vertically fixed to the bottom of the left and right ends of the upper support seat (1). The lead screw (12) is horizontally rotatably connected to the two mounting side plates. The guide rod (11) is horizontally fixed between the two mounting side plates (13); a threaded through hole and a guide through hole are respectively provided between the left and right ends of the mounting seat (15) at positions relative to the lead screw (12) and the guide rod (11); the mounting seat (15) is connected to the lead screw (12) via the threaded through hole; and the guide rod (11) passes through the mounting seat (15) along the guide through hole.

6. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 3, characterized in that: An auxiliary support plate (25) is installed in the lower end of the first drying box (8). The auxiliary support plate (25) divides the internal space of the first drying box (8) into two upper and lower spaces, wherein the upper space is a drying chamber and the lower space is a recovery chamber. The drying chamber is connected to the recovery chamber via a plurality of through holes provided on the first drying box (8). A rotating support seat (26) is fixed on the auxiliary support plate (25). A rotating seat (27) is rotatably connected to the top of the rotating support seat (26). The upper end of the rotating seat (27) extends out of the rotating support seat (26). An outer gear ring is fixedly mounted on the outer wall of the rotating seat (27) extending out of the rotating support seat (26). The outer gear ring is meshed with a rotating drive gear (30). The rotating drive gear (30) is fixedly mounted on the output shaft of the rotating drive motor. The rotating drive motor is installed on the auxiliary support plate (25). The top of the rotating seat (27) is evenly fixed. There are four mounting frames (28), which are arranged opposite to each other in pairs. A clamping electric cylinder is installed in the opposite side of the mounting frames, and the output shaft end of the clamping electric cylinder is connected to the clamping end head (29). The hanging frame (17) is fixed to the top of the rotating seat through the four clamping ends (29) in the front, back, left and right directions. An air heating chamber is provided in the upper end of the second temporary placement seat (3), and an electric heating pipe and a first temperature sensor are installed in the air heating chamber. An air outlet is provided on the side of the air heating chamber facing the first drying box. A hot air collection chamber is provided in the upper end of the third temporary placement seat (4), and an air inlet is provided on the side of the hot air collection chamber facing the first drying box. The first drying box (8) is provided with oblique guide holes on the left and right sides relative to the positions of the air outlet and the air inlet, and the lower end of the guide hole is connected to the drying chamber. The hot air collection chamber is also connected to the air heating chamber through a circulation pipe (31), and a circulation pump is installed on the circulation pipe (31).

7. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 3, characterized in that: The bottom of the drying chamber (6) and the second drying box (10) are provided with two mutually parallel slide rails (24), the right end of the drying chamber (6) is provided with a box door guide frame, a box door (23) is slidably connected in the box door guide frame, the box door (23) is connected to the box door switch electric cylinder (22) installed on the top of the drying chamber (6), the right end of the slide rail (24) extends out of the drying chamber (6), the bottom of the box door (23) is provided with a through groove relative to the position of the slide rail (24), and the fourth temporary placement seat (5 ) is provided with a groove on one side facing the second drying box (10), the groove is connected to the second drying box (10), the grooves of the four temporary seats (5) are connected to the translation push plate through the translation push electric cylinder, a slider matching the slide rail (24) is provided at the bottom of the hanging frame (17), the hanging frame in the second drying box (10) is pushed along the slide rail (24) into the drying chamber (6) by the translation push plate, and a heating resistance wire and a second temperature sensor are installed in the second drying box (10) and the drying chamber (6).

8. A method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to any one of claims 1 or 3, characterized in that: The active components of the impregnation solution in the impregnation box include one or a combination of V, Mo, W, Ce, Co, Mn, and Fe, and the amount of active components added to the inert carrier after the catalyst is formed is 2-5wt% by weight.

9. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 1, characterized in that: The noble metal catalytic active solution in step S5 includes one or a combination of platinum, palladium, rhodium, copper and cerium. The loading amount of the noble metal coated on the catalyst carrier is 0.01-1% of the weight of the carrier.

10. The method for preparing a catalyst for oxidative removal of CO from sintering flue gas according to claim 1, characterized in that: The ultrasonic dip coating machine (19) in step S5 is placed in a water bath (20), a third temperature sensor is provided in the water bath (20), a pressure switch valve (33) connected thereto is installed on the side wall at the lower end of the water bath, the pressure switch valve is connected to the water inlet of a three-way electromagnetic control valve (34), and the first water outlet of the three-way electromagnetic control valve (34) is connected to a reflux pump (37) installed on the side wall of the heating water tank (35) through a first guide pipe (36). The first flow guide pipe is connected to the heating water tank (35) through a reflux pump (37), and a water supply pipe (38) is also connected to the upper side wall of the heating water tank (35). The heating water tank (35) is connected to a water pump (39) installed on the upper outer wall of the water bath (20) through a delivery water pipe (40), and the delivery water pipe (40) is connected to the water bath (20) through the water pump (39). A fourth temperature sensor is installed in the three-way electromagnetic control valve (34) and its first The two water outlets are connected to the water delivery pipe (40) through the second guide pipe (41). A fifth temperature sensor is installed in the heating water tank (35). The pressure switch valve is a one-way valve, which is specifically composed of an outer valve body (43), an inner valve body (42), a valve core (44) and a spring (45). The open end of the outer valve body (43) is installed on the outer wall of the water bath (20) and is connected thereto. The other end of the outer valve body (43) is fixedly mounted on the outer wall of the inner valve body (42). One end of the inner valve body (42) is sealed, and the other end of the inner valve body extends out of the outer valve body and is connected to the water inlet of the three-way electromagnetic control valve (34). The valve core (44) is annular, and the valve core (44) is piston-connected between the outer wall of the inner valve body (42) and the inner wall of the outer valve body (43) and is connected to the outer valve body (43) through a spring (45). An overflow hole (46) is opened on the side wall of the inner valve body (42) in the outer valve body (43), and the overflow hole (46) is sealed by the valve core (44).

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