A preparation system and method for high-iron red mud-based heterogeneous catalyst

Abstract

The present invention belongs to the technical field of catalyst preparation, and in particular, relates to a system and method for preparing a high-iron red mud-based heterogeneous catalyst. The present invention provides a system for preparing a high-iron red mud-based heterogeneous catalyst, comprising a pickling kettle, wherein an acid solution addition port is fixedly connected on the outer wall of the pickling kettle, a treatment cylinder is provided inside the pickling kettle, and immersion holes are evenly distributed on the peripheral side wall of the treatment cylinder; a step-by-step reaction mechanism is used to add acid solution in steps according to the progress of the pickling reaction, and the step-by-step reaction mechanism includes an air pressure channel fixedly connected to the outer wall of the pickling kettle. By setting a step-by-step reaction mechanism, the present invention can make the addition of acid solution in the pickling reaction proceed in steps, and make the pickling reaction of acid solution and red mud raw material proceed in steps, control the rate and intensity of the reaction, avoid overreaction and excessive corrosion of red mud raw material, ensure a more uniform pickling reaction, and avoid excessive reaction in certain areas due to excessive acid solution.

Description

Technical Field

[0001] The invention belongs to the technical field of catalyst preparation, and in particular relates to a preparation system and method of a high-iron red mud-based heterogeneous catalyst. Background Art

[0002] Red mud is a by-product of the production of alumina in the aluminum smelting industry. It is an iron-rich, highly alkaline industrial solid waste. The production of 1 ton of alumina will produce about 1-1.8 tons of red mud. This industrial solid waste has the characteristics of complex composition, large specific surface area, and strong alkalinity. During the storage process, alkali solution may be leached out through the leaching of rainwater, causing soil and groundwater pollution. However, red mud also has the characteristics of stable structure, large specific surface area and abundant pores. These characteristics make it an excellent catalyst and also very suitable as a catalyst carrier. Therefore, its application in the field of environmental protection is increasing. It can not only be used as a flocculant to treat the sludge generated when wastewater is treated, but also as an adsorbent to effectively treat a variety of organic pollutants in water.

[0003] When red mud is used in the preparation of catalysts, it needs to be pickled to remove impurities in the red mud, such as iron oxides, silicates, etc., so as to further extract useful components. However, during the pickling process, red mud is often added directly to the acid solution, resulting in too fast a reaction rate between the acid solution and the red mud raw material, causing uneven reaction, generating unnecessary by-products, and even causing excessive corrosion, resulting in damage to the red mud raw material and affecting the product quality of the prepared red mud raw material. Summary of the invention

[0004] The purpose of the present invention is to address the problems raised in the above-mentioned background technology and to provide a system and method for preparing a high-iron red mud-based heterogeneous catalyst, which can enable the addition of acid solution in the pickling reaction to be carried out step by step, allow the pickling reaction of the acid solution and the red mud raw material to be carried out step by step, control the reaction rate and intensity, and avoid overreaction and excessive corrosion of the red mud raw material.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A preparation system of a high-iron red mud-based heterogeneous catalyst, comprising:

[0007] A pickling kettle, wherein an acid solution adding port is fixedly connected to the outer wall of the pickling kettle, a treatment cylinder is arranged inside the pickling kettle, and immersion holes are evenly distributed on the peripheral side wall of the treatment cylinder;

[0008] A step-by-step reaction mechanism is used for adding acid solution step by step as the pickling reaction proceeds, the step-by-step reaction mechanism includes an air pressure channel fixedly connected to the outer wall of the pickling kettle, the inner wall of the air pressure channel is airtightly and slidably connected to a piston plate, the inner wall of the air pressure channel is fixedly connected to two abutments, a return spring is provided between the piston plate and the two abutments, a first conductive sheet is fixedly installed inside the air pressure channel, a second conductive sheet is fixedly connected to a side wall of the piston plate close to the first conductive sheet, a first opening and closing valve is provided inside the acid solution addition port, the first opening and closing valve is electrically connected to a power supply device through the first conductive sheet and the second conductive sheet, and a control component is also provided at the upper end of the pickling kettle.

[0009] Preferably, the center position of the treatment cylinder is airtightly rotatably connected with an annular sealing frame, the upper end of the annular sealing frame is fixedly connected with a feed hose extending above the pickling kettle, and the lower end of the annular sealing frame is fixedly connected with a discharge hose extending below the pickling kettle.

[0010] Preferably, control valves are provided in both the feed hose and the discharge hose.

[0011] Preferably, the control component includes a PLC control panel fixedly connected to the upper end of the pickling kettle, the upper wall of the pickling kettle is fixedly connected to an exhaust pipe, a second on-off valve is provided inside the exhaust pipe, the PLC control panel controls the first on-off valve to automatically close after being opened for a unit time through an instant timer, the PLC control panel controls the second on-off valve to automatically close after being opened for a unit time through a delay timer, and the time interval between the opening of the first on-off valve and the second on-off valve is greater than the opening time of the first on-off valve.

[0012] Preferably, the inner bottom wall of the pickling kettle is fixedly connected to a drain pipe, and a third opening and closing valve controlled by a PLC control panel is provided in the drain pipe.

[0013] Preferably, a mixing mechanism is also provided inside the pickling kettle for driving the treatment cylinder to perform circular motion and rotation during the pickling process to improve the contact effect between the red mud raw material and the acid solution. The mixing mechanism includes a first gear ring rotatably connected to the side wall of the treatment cylinder, and two limit rods are fixedly connected to the first gear ring. Two circular grooves are provided on the inner side wall of the pickling kettle, and the limit rods are slidably connected to the inner walls of the circular grooves along a circular trajectory. A driving rod is airtightly rotatably connected to the side wall of the pickling kettle, and a first gear meshing with the first gear ring is fixedly connected to one end of the driving rod close to the treatment cylinder, and a rotating rod is coaxially fixedly connected to the side of the treatment cylinder away from the driving rod. A second gear ring is fixedly connected to the inner wall of the pickling kettle away from the driving rod through a support rod, and a second gear meshing with the second gear ring is fixedly connected to the rotating rod.

[0014] Preferably, a driving mechanism is provided on the outer wall of one side of the pickling kettle, which is used to adjust the contact time between the red mud raw material and the acid solution according to the progress of each pickling reaction. The driving mechanism includes a DC motor fixedly connected to the outer wall of the pickling kettle, and a driving gear is fixedly connected to the output end of the DC motor. The driving rod extends outside the pickling kettle and is fixedly connected to a transmission gear meshing with the driving gear. A support plate is fixedly connected to the inside of the air pressure channel, and a sliding rheostat for controlling the power of the DC motor is provided between the support plate and the piston plate.

[0015] Preferably, the sliding rheostat comprises a resistance rod fixedly connected to a support plate, a sliding plate is slidably mounted on the resistance rod, and a connecting rod is fixedly connected between the sliding plate and the piston plate.

[0016] A preparation method for the preparation system of the high-iron red mud-based heterogeneous catalyst comprises the following steps:

[0017] S1. Crushing treatment: crushing the red mud raw material and biomass into powder by a crushing mechanism, and screening the crushed red mud raw material and biomass;

[0018] S2, pickling reaction: the sieved red mud powder is pickled in a pickling kettle to neutralize the alkali therein;

[0019] S3, granulation into balls: drying the acid-washed red mud powder, then mixing it with the screened biomass powder, and granulating it into balls through a molding machine;

[0020] S4. Obtaining the product: heating the mixture under an inert atmosphere for carbonization reaction to obtain a reaction product, cooling, washing and drying the reaction product to obtain a high-iron red mud heterogeneous catalyst.

[0021] Compared with the existing technology, the advantages of the preparation system and method of the high-iron red mud-based heterogeneous catalyst are:

[0022] 1. The present invention sets a step-by-step reaction mechanism. Since hydrogen, carbon dioxide and other gases are produced during the pickling process, the air pressure in the pickling kettle will continue to increase as the pickling reaction proceeds, and the piston plate is driven to move in the air pressure channel through the air pressure difference between the pickling kettle and the outside world. When the reaction rate of the acid solution and the red mud raw material becomes very slow, the second conductive sheet contacts the first conductive sheet, and the PLC control panel opens the first on-off valve for a unit time through the instant timer to add a unit volume of acid solution to the inside of the pickling kettle. Then, the air pressure inside the pickling kettle is restored to normal atmospheric pressure through the second on-off valve. At this time, the acid solution newly added to the inside of the pickling kettle reacts with the red mud raw material for pickling, so that the addition of the acid solution in the pickling reaction is carried out step by step, and the pickling reaction of the acid solution and the red mud raw material is carried out step by step, the reaction rate and intensity are controlled, overreaction and excessive corrosion of the red mud raw material are avoided, the pickling reaction is ensured to be more uniform, and excessive reaction due to excessive acid solution in certain areas is avoided, thereby improving the product quality of the red mud raw material.

[0023] 2. The present invention provides a mixing mechanism to drive the treatment tube to perform circular motion during the pickling process, so that the treatment tube can fully contact various positions of the acid solution after being immersed in the acid solution, and at the same time drive the treatment tube to rotate, so as to avoid the red mud raw material in the treatment tube always accumulating in one place, greatly improve the contact effect between the acid solution and the red mud raw material, make the red mud raw material and the acid solution fully mixed, and improve the rate and uniformity of the pickling reaction.

[0024] 3. The present invention sets a driving mechanism. When the acid solution just enters the pickling kettle each time, the acid solution concentration is high. At this time, the DC motor drives the driving rod to rotate at a faster speed, so that the circular motion and rotation speed of the treatment barrel are faster, so as to avoid the acid solution from contacting the red mud raw material for a long time, resulting in local overreaction, uneven reaction or excessive material loss. After the acid solution is immersed in the pickling kettle for a period of time each time, the acid solution concentration is low. At this time, the driving rod rotates at a slower speed, so that the circular motion and rotation speed of the treatment barrel are slower, and the reaction time is extended, so as to ensure that the acid solution can fully react with all impurities in the red mud, and the contact effect between the red mud raw material and the acid solution can be automatically adjusted according to the concentration of the acid solution, so as to optimize the acidification reaction between the acid solution and the red mud raw material.

[0025] 4. The present invention provides a stirring mechanism. While the DC motor drives the driving rod to rotate, the worm and the worm gear drive the transmission rod to rotate, which further drives the sleeve and the spiral stirring rod to rotate. During the pickling process, the acid solution is fully stirred and mixed, thereby further improving the uniformity of the acidification reaction and improving the product quality of the produced catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a three-dimensional structural schematic diagram of the present invention;

[0027] Figure 2It is a cross-sectional structural schematic diagram of the present invention;

[0028] Figure 3 yes Figure 2 The enlarged view of point A in the middle;

[0029] Figure 4 is a cross-sectional view of the air pressure channel in the present invention;

[0030] Figure 5 It is a partial cross-sectional view of the mixing mechanism in the present invention;

[0031] Figure 6 It is a cross-sectional view of the sealing box in the present invention.

[0032] In the figure: 1, pickling kettle; 11, acid solution addition port; 12, treatment cylinder; 13, immersion hole; 2, step reaction mechanism; 21, air pressure channel; 22, piston plate; 23, stop block; 24, return spring; 25, first conductive sheet; 26, second conductive sheet; 27, first opening and closing valve; 28, control component; 281, PLC control panel; 282, exhaust pipe; 283, second opening and closing valve; 3, annular sealing frame; 31, feed hose; 32, discharge hose; 4, mixing mechanism; 41, first gear ring; 42 , limit rod; 43, circular groove; 44, drive rod; 45, first gear; 46, rotating rod; 47, second gear ring; 48, second gear; 5, sealing box; 51, annular plate; 6, driving mechanism; 61, DC motor; 62, driving gear; 63, transmission gear; 64, support plate; 65, resistance rod; 66, slide; 7, stirring mechanism; 71, sleeve; 72, spiral stirring rod; 73, third gear ring; 74, mounting block; 75, transmission rod; 76, third gear; 77, worm wheel; 78, worm. DETAILED DESCRIPTION

[0033] The following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0034] Example: Refer to Figures 1 to 6 , a preparation system of a high iron red mud-based heterogeneous catalyst, comprising:

[0035] A pickling kettle 1, the outer wall of which is fixedly connected with an acid solution adding port 11, a treatment cylinder 12 is arranged inside the pickling kettle 1, and immersion holes 13 are evenly distributed on the peripheral side wall of the treatment cylinder 12;

[0036] Specifically, the center position of the treatment barrel 12 is airtightly rotatably connected to an annular sealing frame 3, the upper end of the annular sealing frame 3 is fixedly connected to a feed hose 31 extending to the top of the pickling kettle 1, and the lower end of the annular sealing frame 3 is fixedly connected to a discharge hose 32 extending to the bottom of the pickling kettle 1. The red mud raw material can be transported to the annular sealing frame 3 and the treatment barrel 12 through the feed hose 31, and the red mud raw material in the annular sealing frame 3 and the treatment barrel 12 can be transported to the outside through the discharge hose 32. The red mud raw material can be subjected to a drum-type acidification reaction through the treatment barrel 12 to improve the uniformity of the acidification reaction.

[0037] In actual use, the red mud raw material is transported to the annular sealing frame 3 and the inside of the treatment cylinder 12 through the feed hose 31, and the treatment cylinder 12 is immersed in the acid solution. At this time, the acid solution can enter the treatment cylinder 12 and contact the red mud raw material to carry out an acidification reaction on the red mud raw material, while the red mud raw material cannot enter the pickling kettle 1, thereby ensuring the comprehensive collection of the red mud raw material after the subsequent acidification is completed, and preventing the red mud raw material from being scattered in the pickling kettle 1. After the acidification is completed, the red mud raw material is discharged to the outside through the discharge hose 32. The feed hose 31 and the discharge hose 32 are both made of rubber material and have a certain elasticity, thereby ensuring that the subsequent treatment cylinder 12 can perform circular motion.

[0038] In addition, control valves are provided in the feed hose 31 and the discharge hose 32 , and the red mud raw material can be transported and discharged through the feed hose 31 and the discharge hose 32 before and after the acidification reaction is completed.

[0039] The step-by-step reaction mechanism 2 is used for adding acid solution in steps as the pickling reaction proceeds, thereby improving the uniformity of the pickling reaction and making full use of the acid solution. The step-by-step reaction mechanism 2 includes an air pressure channel 21 fixedly connected to the outer wall of the pickling kettle 1, and the inner wall of the air pressure channel 21 is airtightly and slidably connected with a piston plate 22. Two abutments 23 are fixedly connected to the inner wall of the air pressure channel 21, and a return spring 24 is provided between the piston plate 22 and the two abutments 23. A first conductive sheet 25 is fixedly installed inside the air pressure channel 21, and a second conductive sheet 26 is fixedly connected to a side wall of the piston plate 22 close to the first conductive sheet 25. A first opening and closing valve 27 is provided inside the acid solution adding port 11, and the first opening and closing valve 27 is electrically connected to the power supply device through the first conductive sheet 25 and the second conductive sheet 26. A control component 28 is also provided at the upper end of the pickling kettle 1 for automatically adding a certain amount of acid solution after each pickling reaction and restoring the air pressure in the pickling kettle 1 to normal atmospheric pressure.

[0040] Specifically, when the first opening and closing valve 27 is opened, acid liquid can be added through the acid liquid addition port 11 until the acid liquid completely immerses the treatment tube 12, thereby ensuring the acidification reaction of the red mud raw material inside the treatment tube 12. Here, the liquid level height of the acid liquid can be detected by a liquid level meter to ensure that the acid liquid can completely immerse the treatment tube 12.

[0041] The control component 28 includes a PLC control panel 281 fixedly connected to the upper end of the pickling kettle 1. The upper wall of the pickling kettle 1 is fixedly connected to an exhaust pipe 282. A second opening and closing valve 283 is provided inside the exhaust pipe 282. The PLC control panel 281 controls the first opening and closing valve 27 to automatically close after being opened for a unit time through an instant timer. The PLC control panel 281 controls the second opening and closing valve 283 to automatically close after being opened for a unit time through a delay timer.

[0042] Specifically, the time interval between the opening of the first on-off valve 27 and the second on-off valve 283 is greater than the opening time of the first on-off valve 27. Therefore, the first on-off valve 27 is closed, and the second on-off valve 283 is opened only after the addition of the acid solution is completed, so that the air pressure in the treatment tube 12 is restored to normal atmospheric pressure, thereby avoiding the premature recovery of the air pressure in the treatment tube 12, which causes the first conductive sheet 25 and the second conductive sheet 26 to no longer contact, resulting in premature cessation of the addition of the acid solution, thereby ensuring that a certain amount of acid solution is added each time.

[0043] Specifically, the inner bottom wall of the pickling kettle 1 is fixedly connected to a drain pipe, and a third on-off valve controlled by a PLC control panel 281 is provided in the drain pipe. Under the action of the PLC control panel 281, the third on-off valve can be opened for a period of time before the first on-off valve 27 is opened, to ensure that each time before the acid liquid acidifies the red mud raw material, the acid liquid after acidification can be discharged, to avoid the influence of the used acid liquid on the subsequent acidification reaction, and to prevent the acid liquid from overflowing due to excessive liquid level.

[0044] In view of the problem that in the prior art, red mud is often directly added to the acid solution during the pickling process, which leads to an overly fast reaction rate between the acid solution and the red mud raw material, resulting in uneven reaction, generation of unnecessary by-products, and even possible excessive corrosion, resulting in damage to the red mud raw material, and affecting the product quality of the prepared red mud raw material, the present invention provides a step-by-step reaction mechanism 2. During the pickling process, a unit volume of acid solution is added to the interior of the pickling kettle 1 through the acid solution addition port 11. Since gases such as hydrogen and carbon dioxide are produced during the pickling process, the air pressure in the pickling kettle 1 will continue to increase as the pickling reaction proceeds, and the piston plate 22 is driven to move outward in the air pressure channel 21 through the air pressure difference between the pickling kettle 1 and the outside world. After the pickling reaction proceeds to a certain extent, the reaction rate between the acid solution and the red mud raw material becomes very slow. At this time, the piston plate 22 moves to the second guide port in the air pressure channel 21. The electric sheet 26 contacts the first conductive sheet 25, so that the first on-off valve 27 is connected to the power supply device. At this time, the PLC control panel 281 opens the first on-off valve 27 for a unit time through the instant timer to add a unit volume of acid solution into the pickling kettle 1. After the pickling solution is completely added to the pickling kettle 1, the first on-off valve 27 is closed, and the PLC control panel 281 opens the second on-off valve 283 for a unit time through the delay timer to restore the air pressure inside the pickling kettle 1 to normal atmospheric pressure. At this time, the acid solution newly added to the pickling kettle 1 reacts with the red mud raw material for pickling, so that the addition of acid solution in the pickling reaction is carried out step by step, and the pickling reaction between the acid solution and the red mud raw material is carried out step by step, so as to control the reaction rate and intensity, avoid overreaction and excessive corrosion of the red mud raw material, ensure a more uniform pickling reaction, avoid excessive reaction in certain areas due to excessive acid solution, and improve the product quality of the red mud raw material.

[0045] A mixing mechanism 4 is also provided inside the pickling kettle 1, which is used to drive the treatment cylinder 12 to perform circular motion and rotation during the pickling process to improve the contact effect between the red mud raw material and the acid solution. The mixing mechanism 4 includes a first toothed ring 41 rotatably connected to the side wall of the treatment cylinder 12, and two limit rods 42 are fixedly connected to the first toothed ring 41. Two circular grooves 43 are provided on the inner side wall of the pickling kettle 1, and the limit rods 42 are slidably connected to the inner walls of the circular grooves 43 along a circular trajectory. A driving rod 44 is airtightly rotatably connected to the side wall of the pickling kettle 1, and a first gear 45 meshing with the first toothed ring 41 is fixedly connected to the end of the driving rod 44 close to the treatment cylinder 12. A rotating rod 46 is coaxially fixedly connected to the side of the treatment cylinder 12 away from the driving rod 44. A second toothed ring 47 is fixedly connected to the inner wall of the pickling kettle 1 away from the driving rod 44 through a support rod, and a second gear 48 meshing with the second toothed ring 47 is fixedly connected to the rotating rod 46.

[0046] Specifically, the circumferential sides of the first gear ring 41 and the second gear ring 47 are both covered with a sealing box 5, and an annular plate 51 is air-tightly rotatably connected to the side wall of the sealing box 5. The first gear 45 and the second gear 48 are both air-tightly rotatably connected to the annular plates 51 at corresponding positions. Through the arrangement of the sealing box 5 and the annular plate 51, the acid liquid can be prevented from entering the meshing parts of the first gear 45 and the first gear ring 41, the second gear 48 and the second gear ring 47, and affecting the normal operation of the mixing mechanism 4.

[0047] In order to improve the contact effect between the acid solution and the red mud raw material, the present invention sets a mixing mechanism 4. During the pickling process, the first gear 45 can be driven to rotate by the driving rod 44, so that the first gear ring 41 can perform a circular motion under the action of the limiting rod 42 and the circular groove 43, and further drive the treatment tube 12 to perform a circular motion, so that the treatment tube 12 can fully contact various positions of the acid solution after being immersed in the acid solution. At the same time, during the circular motion of the treatment tube 12, the second gear 48 can be driven to perform a circular motion along the second gear ring 47, and then drive the treatment tube 12 to rotate, so as to avoid the red mud raw material in the treatment tube 12 always accumulating in one place, resulting in a reduction in the contact effect between it and the acid solution, which can greatly improve the contact effect between the acid solution and the red mud raw material, make the red mud raw material and the acid solution fully mixed, and improve the rate and uniformity of the pickling reaction.

[0048] A driving mechanism 6 is provided on the outer wall of one side of the pickling kettle 1, which is used to adjust the contact time between the red mud raw material and the acid solution according to the progress of each pickling reaction. The driving mechanism 6 includes a DC motor 61 fixedly connected to the outer wall of the pickling kettle 1, and a driving gear 62 is fixedly connected to the output end of the DC motor 61. The driving rod 44 extends to the outside of the pickling kettle 1 and is fixedly connected to a transmission gear 63 meshing with the driving gear 62. A support plate 64 is fixedly connected to the inside of the air pressure channel 21, and a sliding rheostat for controlling the power of the DC motor 61 is provided between the support plate 64 and the piston plate 22.

[0049] Specifically, the sliding rheostat includes a resistance rod 65 fixedly connected to the support plate 64, a sliding plate 66 is slidably mounted on the resistance rod 65, a connecting rod is fixedly connected between the sliding plate 66 and the piston plate 22, wherein the first conductive plate 25 is fixedly connected to the end of the resistance rod 65.

[0050] In order to avoid the influence of the concentration change of the acid solution on the pickling reaction, the present invention sets a driving mechanism 6. During the pickling process, the DC motor 61 can drive the driving gear 62 to rotate, and further drive the driving rod 44 to rotate through the transmission gear 63, so that the mixing mechanism 4 starts to work. Every time the acid solution just enters the pickling kettle 1, the acid solution concentration is high, the piston plate 22 is located in the air pressure channel 21 near the inner side of the pickling kettle 1, and the slide 66 is located on the resistance rod 65 near the inner side of the pickling kettle 1. The resistance value of the circuit where the DC motor 61 is located is small, and the current is large, so that the rotation speed of the driving rod 44 is faster, and the circular motion and rotation speed of the processing cylinder 12 are faster, so as to avoid the acid solution from being stirred for a long time. The contact between the acid and the red mud raw material causes local overreaction, resulting in uneven reaction or excessive material loss. After each time the acid is immersed in the pickling kettle 1 for a period of time, the acid concentration is low, and the piston plate 22 is located in the air pressure channel 21 near the outside of the pickling kettle 1. At this time, the slide 66 is located on the resistance rod 65 near the outside of the pickling kettle 1. The resistance value of the circuit where the DC motor 61 is located is large and the current is small, so that the rotation speed of the drive rod 44 is slow, and the circular motion and rotation speed of the processing cylinder 12 are slow, which prolongs the reaction time, ensures that the acid can fully react with all impurities in the red mud raw material, and can automatically adjust the contact effect between the red mud raw material and the acid according to the concentration of the acid, so as to optimize the acidification reaction between the acid and the red mud raw material.

[0051] The interior of the pickling kettle 1 is provided with a stirring mechanism 7 controlled by a driving mechanism 6, which is used to drive the acid solution to be in a flowing state during the pickling process to improve the effect of the acidification reaction. The stirring mechanism 7 includes a sleeve 71 which is airtightly rotatably connected to the inner bottom wall of the pickling kettle 1, and the sleeve 71 is airtightly connected to the discharge hose 32. The portion of the sleeve 71 in the pickling kettle 1 is fixedly connected with a spiral stirring rod 72, and the portion of the sleeve 71 extending below the pickling kettle 1 is fixedly connected with a third gear ring 73. A mounting block 74 is fixedly connected to the outer wall of the pickling kettle 1, and a transmission rod 75 is rotatably connected to the mounting block 74. The bottom end of the transmission rod 75 is fixedly connected with a third gear 76 meshing with the third gear ring 73, and the top end of the transmission rod 75 is fixedly connected with a worm gear 77. The portion of the drive rod 44 extending outside the pickling kettle 1 is fixedly connected with a worm 78 meshing with the worm gear 77.

[0052] In addition, the present invention provides a stirring mechanism 7. When the DC motor 61 drives the driving rod 44 to rotate and the mixing mechanism 4 works, the transmission rod 75 can be driven to rotate through the worm 78 and the worm wheel 77, and the third gear ring 73 is further driven to rotate through the third gear 76, so that the sleeve 71 and the spiral stirring rod 72 are rotated, and the acid solution is fully stirred and mixed during the pickling process, thereby further improving the uniformity of the acidification reaction and improving the product quality of the produced catalyst.

[0053] A preparation method for the preparation system of the high-iron red mud-based heterogeneous catalyst comprises the following steps:

[0054] S1. Crushing treatment: crushing the red mud raw material and biomass into powder by a crushing mechanism, and screening the crushed red mud raw material and biomass;

[0055] S2, pickling reaction: the sieved red mud powder is pickled using a pickling kettle 1 to neutralize the alkali therein;

[0056] S3, granulation into balls: drying the acid-washed red mud powder, then mixing it with the screened biomass powder, and granulating it into balls through a molding machine;

[0057] S4. Obtaining the product: heating the mixture under an inert atmosphere for carbonization reaction to obtain a reaction product, cooling, washing and drying the reaction product to obtain a high-iron red mud heterogeneous catalyst.

[0058] It is worth mentioning that the above method can prepare high-iron red mud heterogeneous catalyst from red mud raw materials, which not only makes full use of the red mud raw materials, but also gives full play to the catalytic potential of iron in the red mud, generating greater economic and environmental benefits.

[0059] The present invention can be explained by the following operation mode:

[0060] The control valve in the feed hose 31 is opened and the control valve in the discharge hose 32 is closed, and the red mud raw material is transported to the annular sealing frame 3 and the inside of the treatment tube 12 through the feed hose 31, and the treatment tube 12 is immersed in the acid solution. At this time, the acid solution can enter the treatment tube 12 to contact with the red mud raw material, and the red mud raw material is acidified. The red mud raw material cannot enter the pickling kettle 1. After the red mud raw material is transported, the control valve in the feed hose 31 is closed;

[0061] Since gases such as hydrogen and carbon dioxide are produced during the pickling process, the air pressure in the pickling kettle 1 will continue to increase as the pickling reaction proceeds, and the piston plate 22 is driven to move outward in the air pressure channel 21 through the air pressure difference between the pickling kettle 1 and the outside world. After the pickling reaction proceeds to a certain extent, the second conductive sheet 26 contacts the first conductive sheet 25, and the PLC control panel 281 opens the first on-off valve 27 for a unit time through an instant timer to add a unit volume of acid solution to the inside of the pickling kettle 1. After the pickling solution is completely added to the inside of the pickling kettle 1, the first on-off valve 27 is closed, and the PLC control panel 281 opens the second on-off valve 283 for a unit time through a delay timer to restore the air pressure inside the pickling kettle 1 to normal atmospheric pressure, so that the addition of acid solution in the pickling reaction is carried out step by step;

[0062] The DC motor 61 is turned on to drive the driving gear 62 to rotate, and the driving rod 44 is further driven to rotate through the transmission gear 63, and the driving rod 44 drives the first gear 45 to rotate, so that the first gear ring 41 can perform a circular motion under the action of the limiting rod 42 and the circular groove 43, and further drives the processing barrel 12 to perform a circular motion, so that the processing barrel 12 can be fully contacted with various positions of the acid solution after being immersed in the acid solution. At the same time, during the process of the processing barrel 12 performing a circular motion, the second gear 48 can be driven to perform a circular motion along the second gear ring 47, and then the processing barrel 12 is driven to rotate, so as to prevent the red mud raw materials in the processing barrel 12 from always accumulating in one place;

[0063] When the acid solution just enters the pickling kettle 1, the acid solution concentration is high, the slide 66 is located on the resistance rod 65 near the inner side of the pickling kettle 1, and the DC motor 61 drives the driving rod 44 to rotate at a faster speed, so that the circular motion and rotation speed of the treatment barrel 12 are faster, so as to avoid the acid solution from contacting the red mud raw material for a long time and causing local overreaction. After the acid solution is immersed in the pickling kettle 1 for a period of time, the acid solution concentration is low, the slide 66 is located on the resistance rod 65 near the outer side of the pickling kettle 1, and the DC motor 61 drives the driving rod 44 to rotate at a slower speed, so that the circular motion and rotation speed of the treatment barrel 12 are slower, and the reaction time is prolonged.

[0064] After the acidification is completed, the control valve in the discharge hose 32 is opened to discharge the red mud raw material to the outside through the discharge hose 32 .

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A system for preparing a high-iron red mud-based heterogeneous catalyst, characterized in that: include: A pickling kettle (1), wherein an acid solution adding port (11) is fixedly connected to the outer wall of the pickling kettle (1), a treatment cylinder (12) is provided inside the pickling kettle (1), and immersion holes (13) are evenly distributed on the peripheral side wall of the treatment cylinder (12); The step-by-step reaction mechanism (2) is used for adding acid solution step by step as the pickling reaction proceeds, the step-by-step reaction mechanism (2) comprising a gas pressure channel (21) fixedly connected to the outer wall of the pickling kettle (1), the inner wall of the gas pressure channel (21) being airtightly slidably connected to a piston plate (22), the inner wall of the gas pressure channel (21) being fixedly connected to two abutting blocks (23), a return spring (24) being arranged between the piston plate (22) and the two abutting blocks (23), and a first fixedly installed inner wall of the gas pressure channel (21) A conductive sheet (25), a second conductive sheet (26) is fixedly connected to a side wall of the piston plate (22) close to the first conductive sheet (25), a first on-off valve (27) is provided inside the acid liquid addition port (11), the first on-off valve (27) is electrically connected to a power supply device via the first conductive sheet (25) and the second conductive sheet (26), and a control component (28) is further provided at the upper end of the pickling kettle (1), the control component (28) comprising an exhaust pipe (282) fixedly connected to the upper wall of the pickling kettle (1); The center of the treatment cylinder (12) is connected to an annular sealing frame (3) in an airtight rotational manner, the upper end of the annular sealing frame (3) is fixedly connected to a feed hose (31) extending above the pickling kettle (1), and the lower end of the annular sealing frame (3) is fixedly connected to a discharge hose (32) extending below the pickling kettle (1); The control component (28) further comprises a PLC control panel (281) fixedly connected to the upper end of the pickling kettle (1); a second on-off valve (283) is provided inside the exhaust pipe (282); the PLC control panel (281) controls the first on-off valve (27) to automatically close after being opened for a unit time through an instant timer; the PLC control panel (281) controls the second on-off valve (283) to automatically close after being opened for a unit time through a delay timer; and the time interval between the opening of the first on-off valve (27) and the second on-off valve (283) is greater than the opening time of the first on-off valve (27); The pickling kettle (1) is further provided with a mixing mechanism (4) inside, which is used to drive the treatment cylinder (12) to perform circular motion and rotation during the pickling process, the mixing mechanism (4) comprising a first toothed ring (41) rotatably connected to the side wall of the treatment cylinder (12), two limit rods (42) being fixedly connected to the first toothed ring (41), two circular grooves (43) being provided on the inner side wall of the pickling kettle (1), the limit rods (42) being slidably connected to the inner wall of the circular grooves (43) along a circular trajectory, and the side wall of the pickling kettle (1) is provided with a plurality of stop rods (42) which are arranged on the inner side wall of the pickling kettle (1). A driving rod (44) is connected to the wall in an airtight rotational manner; one end of the driving rod (44) close to the treatment cylinder (12) is fixedly connected to a first gear (45) meshing with a first gear ring (41); a rotating rod (46) is coaxially fixedly connected to a side of the treatment cylinder (12) away from the driving rod (44); a second gear ring (47) is fixedly connected to the inner wall of the pickling kettle (1) on a side away from the driving rod (44) via a support rod; and a second gear (48) meshing with the second gear ring (47) is fixedly connected to the rotating rod (46).

2. The preparation system of high iron red mud-based heterogeneous catalyst according to claim 1, characterized in that: The feed hose (31) and the discharge hose (32) are both provided with control valves.

3. The preparation system of high iron red mud-based heterogeneous catalyst according to claim 2, characterized in that: The inner bottom wall of the pickling kettle (1) is fixedly connected to a drain pipe, and a third on-off valve controlled by a PLC control panel (281) is provided in the drain pipe.

4. The preparation system of high iron red mud-based heterogeneous catalyst according to claim 3, characterized in that: A driving mechanism (6) is provided on one side outer wall of the pickling kettle (1) for adjusting the contact time between the red mud raw material and the acid solution according to the progress of each pickling reaction. The driving mechanism (6) comprises a DC motor (61) fixedly connected to the outer wall of the pickling kettle (1), a driving gear (62) fixedly connected to the output end of the DC motor (61), the driving rod (44) extending outside the pickling kettle (1) and fixedly connected to a transmission gear (63) meshing with the driving gear (62), a support plate (64) fixedly connected to the interior of the air pressure channel (21), and a sliding rheostat for controlling the power of the DC motor (61) is provided between the support plate (64) and the piston plate (22).

5. The preparation system of high iron red mud-based heterogeneous catalyst according to claim 4, characterized in that: The sliding rheostat comprises a resistance rod (65) fixedly connected to a support plate (64), a sliding plate (66) being slidably mounted on the resistance rod (65), and a connecting rod being fixedly connected between the sliding plate (66) and the piston plate (22).

6. The preparation system of high iron red mud-based heterogeneous catalyst according to claim 5, characterized in that: The pickling kettle (1) is provided with a stirring mechanism (7) controlled by a driving mechanism (6) for driving the acid solution to flow during the pickling process. The stirring mechanism (7) comprises a sleeve (71) rotatably connected to the bottom wall of the pickling kettle (1) in an airtight manner. The sleeve (71) is airtightly connected to a discharge hose (32). The portion of the sleeve (71) located in the pickling kettle (1) is fixedly connected to a spiral stirring rod (72). The portion of the sleeve (71) extending below the pickling kettle (1) is fixedly connected to the bottom wall of the pickling kettle (1). A third gear ring (73) is connected, a mounting block (74) is fixedly connected to the outer wall of the pickling kettle (1), a transmission rod (75) is rotatably connected to the mounting block (74), a third gear (76) meshing with the third gear ring (73) is fixedly connected to the bottom end of the transmission rod (75), a worm gear (77) is fixedly connected to the top end of the transmission rod (75), and a worm (78) meshing with the worm gear (77) is fixedly connected to the portion of the drive rod (44) extending outside the pickling kettle (1).

7. A method for preparing a heterogeneous catalyst using the preparation system according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1. Crushing treatment: crushing the red mud raw material and biomass into powder by a crushing mechanism, and screening the crushed red mud raw material and biomass; S2, pickling reaction: using the preparation system described in claims 1 to 6 to pickle the sieved red mud powder to neutralize the alkali therein; S3, granulation into balls: drying the acid-washed red mud powder, then mixing it with the screened biomass powder, and granulating it into balls through a molding machine; S4. Obtaining the product: heating the mixture under an inert atmosphere for carbonization reaction to obtain a reaction product, cooling, washing and drying the reaction product to obtain a high-iron red mud heterogeneous catalyst.

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