A catalyst slurry automatic coating system and coating process

Abstract

The present invention discloses a catalyst slurry automatic coating system and coating process, the coating system includes a slurry supply device, an upper coating chamber, a lower coating chamber, a back suction device, a transfer device, a first weighing device, a second weighing device and a third weighing device; the slurry supply device includes a slurry tank and a flow meter; the upper coating chamber and the lower coating chamber are both connected to the slurry tank, the upper coating chamber and the lower coating chamber are arranged one by one, and there is a space for accommodating a catalyst carrier between the two, and the slurry tank conveys slurry to the catalyst carrier through the upper coating chamber or the lower coating chamber; the first weighing device is used to measure the original weight of the catalyst carrier to be coated with slurry, and the second weighing device is used to measure the weight of the catalyst carrier after the slurry is coated once. The automatic coating system of the present invention can be selected according to the characteristics of the slurry to be coated, and different catalyst carriers can be coated with slurry to meet different needs; it can ensure the accuracy and uniformity of the slurry coating in the carrier.

Description

Technical Field

[0001] The invention relates to the field of catalyst slurry coating process equipment, and in particular to an automatic catalyst slurry coating system and coating process. Background Art

[0002] Automobile catalyst is the most effective and key automobile component that uses effective catalytic purification technology to reduce harmful substances in automobile exhaust. Automobile catalyst is a complex of a series of chemical materials, consisting of four parts: catalyst carrier, coating, catalyst additive and active ingredient.

[0003] Catalyst coating is the second process in catalyst production and also the most critical link. Based on the two major reaction functions of oxidation catalysis and reduction catalysis, as well as the exhaust components for different working conditions, automotive catalysts have derived different products such as TWC, DOC, SCR, DPF, POC, ASC, etc. The slurry properties, coating methods, and coating parameters required by different products are also completely different. The various slurry properties of the National VI catalyst are relatively wide, including non-Newtonian fluid slurries with high solid content, as well as thin slurries with low suspension properties and weak viscoelastic properties. At the same time, due to the large changes in the physical properties of the National VI catalyst raw materials, the material particle size is greatly reduced, the chemical activity of the catalyst is increased, and the number of coating layers of each catalyst carrier is greatly increased.

[0004] Since the carrier has thousands of pores, if the thickness of the catalyst coating in each pore is inconsistent or the coating height is inconsistent, the catalytic purification effect will be inconsistent when the exhaust gas flows through the catalyst pores, and the purification rate will decrease. This is called uneven coating.

[0005] The operation process of the traditional coating process is complicated, requiring a lot of manual operation, and the coating change time is long and the efficiency is low. At present, the domestic catalyst coating system can generally only meet a certain specific coating method, and the cycle from design to installation and commissioning is relatively long, the cost ratio is high, and the later expansion capacity is limited. Once the production enterprise needs to expand the product type or production capacity according to its own development, it needs to customize a new coating system, which increases the investment cost of the enterprise, is time-consuming and labor-intensive, and also takes up a lot of production space.

[0006] At present, domestic coating equipment generally has low coating accuracy and poor repeatability. There are obvious technical bottlenecks under the National VI standard, especially on large-size carriers (over 300mm) and non-through-hole carriers (such as DPF), where there may be uneven coating.

[0007] At present, some coating processes in China use compressed air blowing, which causes the compressed air pressure to leak out, resulting in serious slurry waste and inability to effectively and reasonably recover the slurry; the air energy consumption is high and the process parameters cannot be adjusted automatically.

[0008] At present, the domestic quantitative feeding coating process has very high requirements on the slurry characteristics and carrier characteristics, and has great limitations in use. In particular, it is impossible to effectively control the uniformity of half-coating, which may bring the risk of pore blockage and excessive back pressure.

[0009] In addition, as companies increase their research and development efforts on catalyst products and various new catalyst formulas are put on the market, companies are often unable to confirm coating methods and coating parameters based on traditional experience, and are unable to give full play to the advantages and characteristics of the original coating equipment, which also leads to quality instability, reduced efficiency, and more material loss. Summary of the invention

[0010] In order to solve the problems existing in the prior art, the present invention provides a catalyst slurry automatic coating system and coating process, which can ensure the uniformity and accuracy of catalyst coating. The technical solution is as follows:

[0011] On the one hand, the present invention provides a catalyst slurry automatic coating system, the coating system is used to coat the catalyst slurry into the catalyst carrier, the coating system includes a slurry supply device, one or more upper coating chambers, one or more lower coating chambers, a back suction device connected to the lower coating chamber, a transfer device for transferring the catalyst carrier, a first weighing device for measuring the weight of the catalyst carrier, a second weighing device and a third weighing device;

[0012] The slurry supply device includes a slurry tank and a flow meter, and the flow meter is used to measure the volume of the slurry transported from the slurry tank to the upper coating chamber or the lower coating chamber;

[0013] The upper coating chamber and the lower coating chamber are both connected to the slurry tank, and the automatic coating system has a coating state. When in the coating state, the upper coating chamber and the lower coating chamber are arranged one by one, and there is a space for accommodating the catalyst carrier between the two. The slurry tank transports the slurry to the catalyst carrier through the upper coating chamber or the lower coating chamber;

[0014] The first weighing device and the second weighing device are respectively arranged on both sides of a lower coating cavity, the first weighing device is used to measure the original weight of the catalyst carrier to be coated with slurry, and the second weighing device is used to measure the weight of the catalyst carrier after the slurry is coated once; the third weighing device and the second weighing device are arranged on both sides of another lower coating cavity, and are used to measure the weight of the catalyst carrier after the slurry is coated twice;

[0015] The suction device is used to discharge the slurry from the lower coating chamber.

[0016] Further, the upper coating chamber comprises an upper coating platform, an upper cavity for accommodating one end of the catalyst carrier is provided on the upper coating platform, an annular screen and a first sealing ring arranged below the screen are arranged on the inner wall of the upper cavity, and the first sealing ring is arranged along the outer side wall of the upper cavity;

[0017] The lower coating chamber includes a lower coating platform, on which a lower cavity for accommodating the other end of the catalyst carrier is provided, and an outer wall of the lower cavity is provided with a second sealing ring with a hollow structure, and the first sealing ring and the second sealing ring are used to synchronously clamp the catalyst carrier when the catalyst carrier is arranged between the upper cavity and the corresponding lower cavity.

[0018] Furthermore, the upper coating chamber includes a first upper coating chamber and a second upper coating chamber, the lower coating chamber includes a first lower coating chamber arranged opposite to the first upper coating chamber when the slurry is coated once, and a second lower coating chamber arranged opposite to the second upper coating chamber when the slurry is coated twice, and the first weighing device, the first lower coating chamber, the second weighing device, the second lower coating chamber and the third weighing device are arranged side by side in sequence.

[0019] Further, a stirring device is provided in the slurry tank, and a plurality of slurry feed ports and a plurality of return ports are provided on the slurry tank, wherein the feed ports are connected to the feed pump via a pipeline, and the return ports are connected to the return pump via a pipeline, and a switching valve port is fixedly provided on the pipeline; a jacket layer is provided on the outer surface of the slurry tank, and a containing cavity is formed between the jacket layer and the slurry tank, and a temperature sensor capable of extending into the slurry tank is provided on the jacket layer;

[0020] Furthermore, the slurry tank is also provided with a liquid level sensor, a density sensor and a viscosity sensor, the liquid level sensor is used to detect the capacity of the slurry in the slurry tank, the density sensor is used to detect the density of the slurry in the slurry tank, and the viscosity sensor is used to detect the viscosity of the slurry in the slurry tank.

[0021] Furthermore, the catalyst slurry automatic coating system also includes a drying device for heating the catalyst carrier to be coated with the slurry, and the drying device has a preheating chamber for accommodating the catalyst carrier and a hot air blower for providing heat and blowing the heat to the preheating chamber.

[0022] Furthermore, the slurry supply device also includes a delivery pump and a pressure-stabilizing valve, wherein the delivery pump is used to deliver the slurry in the slurry tank to the upper coating chamber or the lower coating chamber through a connecting hose, and the pressure-stabilizing valve is arranged at the end of the delivery pump outlet pipe; the back-suction device includes a vacuum tank connected to the lower coating chamber and a vacuum pump connected to the vacuum tank;

[0023] The transfer device includes a robotic arm, a drag chain arranged on the robotic arm, a driving mechanism for driving the drag chain to move, and a plurality of robotic claws. The movement of the drag chain can drive the movement of the robotic claws. An upper coating cavity can be fixedly connected to a mechanical claw, so that the upper coating cavity can move with the mechanical claw.

[0024] On the other hand, the present invention also provides a coating process based on the automatic catalyst slurry coating system, which includes a double coating process, which means that the slurry for the two coatings enters the catalyst carrier through two different upper coating cavities respectively; or the slurry for the two coatings enters the catalyst carrier through two different lower coating cavities respectively; or the slurry for the first coating first enters the catalyst carrier through the upper coating cavity, and the slurry for the second coating enters the catalyst carrier through the lower coating cavity; or the slurry for the first coating first enters the catalyst carrier through the lower coating cavity, and the slurry for the second coating enters the catalyst carrier through the upper coating cavity.

[0025] The two-coating process comprises the following steps:

[0026] S1, setting a preset first capacity threshold range of the slurry to be coated and a preset qualified weight and qualified range of the catalyst carrier;

[0027] S2, a first weighing device measures the original weight of the catalyst carrier before coating;

[0028] S3, the slurry enters the catalyst carrier for a coating, and a second weighing device measures the first weight of the catalyst carrier after the coating;

[0029] S4, judging whether the first weight of the catalyst carrier after the first coating is within the qualified range, if not, executing step S5; if yes, the weight of the catalyst carrier is qualified;

[0030] S5, calculating the difference between the qualified weight and the first weight, if the difference is zero, the weight of the catalyst carrier is qualified; if the difference is positive, that is, the first weight is lower than the qualified weight, then executing step S6; if the difference is negative, that is, the first weight is higher than the qualified weight, then executing step S8;

[0031] S6, calculating a preset second capacity threshold range of the slurry required for the secondary coating, the slurry enters the catalyst carrier for secondary coating, and then using a third weighing device to measure the weight of the catalyst carrier after the two coatings to obtain a second weight;

[0032] S7, judging whether the second weight of the catalyst carrier after the secondary coating in step S6 is within the preset qualified range, if so, the weight of the catalyst carrier after coating is qualified; if not, the weight of the catalyst carrier after coating is unqualified, and calculating the deviation percentage of the unqualified weight, and adjusting the slurry required for the secondary coating in step S6 according to the preset calculation formula;

[0033] S8, opening the back-sucking device to discharge the slurry exceeding the preset qualified range, and then using the third weighing device to measure the weight of the catalyst carrier after the slurry is discharged to obtain a third weight;

[0034] S9. Determine whether the third weight of the catalyst carrier after discharging the slurry in step S8 is within the preset qualified range. If so, the weight of the coated catalyst carrier is qualified; if not, the weight of the catalyst carrier is unqualified, and calculate the deviation percentage of the unqualified weight, and adjust the operating parameters of the back-absorption device in step S8 according to the preset calculation formula.

[0035] Furthermore, according to the viscosity of different catalyst slurries or the mesh size of catalyst carriers or the coating ratio, an optimized coating method can be selected.

[0036] If the viscosity of the catalyst slurry is high, or the catalyst carrier has a low mesh number, or is fully coated, the slurry enters the catalyst carrier from top to bottom through the upper coating cavity, that is, the upper coating method is selected to obtain a product with optimized uniformity and accuracy;

[0037] If the viscosity of the catalyst slurry is small, or the catalyst carrier has a high mesh number, or is partially coated, the slurry enters the catalyst carrier from bottom to top through the lower coating cavity, that is, the lower coating method is selected to obtain a product with optimized uniformity and accuracy.

[0038] The beneficial effects brought by the technical solution provided by the present invention are as follows:

[0039] a. The catalyst slurry automatic coating system of the present invention can ensure the accuracy and uniformity of the carrier coating, and can also avoid the deviation of the temperature, viscosity, density and concentration of the slurry before and after the entire coating process;

[0040] b. The coating system and coating process involved in the present invention can meet the coating requirements of various National VI catalysts and ensure the coating performance of the catalyst;

[0041] c. The coating system of the present invention is fully suitable for automatically coating catalyst slurries of various types and characteristics; the equipment has a compact structure and fully automated operation, and can maximize the utilization of equipment production requirements; it adopts a rapid changeover design to meet the production of various catalysts; the characteristics of various carriers and slurries are automatically compensated, which improves production efficiency and reduces the labor intensity and health damage of operators;

[0042] d. The coating process involved in the present invention can complete the catalyst slurry coating in a relatively short time, automatically correct the process deviation, ensure the accuracy of the coating slurry, reduce material leakage and loss, so as to improve production efficiency, and is simple to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0044] Figure 1 is a three-dimensional diagram of a catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0045] Figure 2 is a front view of a catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0046] Figure 3 It is a left view of the catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0047] Figure 4 is a top view of a catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0048] Figure 5 is a side view of an upper coating chamber of a catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0049] Figure 6 is a side view of a lower coating chamber of a catalyst slurry automatic coating system provided by an embodiment of the present invention;

[0050] Figure 7 It is a structural diagram of a slurry tank of a catalyst slurry automatic coating system provided in an embodiment of the present invention;

[0051] Figure 8 It is a flow chart of a double coating method of the catalyst slurry automatic coating system provided in an embodiment of the present invention.

[0052] Among them, the figure marks include: 1-slurry supply device, 11-slurry tank, 111-liquid level sensor, 112-feed port, 113-viscosity sensor, 114-jacket layer, 115-temperature sensor, 116-stirring device, 12-delivery pump, 13-pressure regulating valve, 14-return pump, 15-bracket, 16-flow meter, 17-connecting pipe, 211-upper cavity, 212-screen, 213-first sealing ring, 214-first coating valve, 215-first air source control valve, 216-level switch, 221-lower cavity, 222-second sealing ring , 223-vacuum suction valve, 224-second coating valve, 225-second air source control valve, 24-first upper coating chamber, 25-first lower coating chamber, 26-second upper coating chamber, 27-second lower coating chamber, 3-return suction device, 31-vacuum tank, 32-vacuum pump, 33-vacuum sensor, 4-transfer device, 41-mechanical arm, 42-drag chain, 43-driving mechanism, 44-mechanical claw, 5-first weighing device, 6-second weighing device, 7-third weighing device, 8-drying device, 81-preheating chamber, 82-hot air blower, 9-catalyst carrier. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0054] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, device, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0055] In one embodiment of the present invention, a catalyst slurry automatic coating system is provided. Figures 1 to 4, which is used to coat catalyst slurry into a catalyst carrier, and includes a slurry supply device 1, one or more upper coating chambers, one or more lower coating chambers, a back-suction device 3 connected to the lower coating chamber, a transfer device 4 for transferring the catalyst carrier, and a first weighing device 5 and a second weighing device 6 for measuring the weight of the catalyst carrier. The automatic coating system also includes a controller connected to the slurry supply device 1, the back-suction device 3 and the transfer device 4.

[0056] The catalyst slurry automatic coating system also includes a drying device 8 for drying the catalyst carrier to be coated, the drying device 8 has a preheating chamber 81 for the catalyst carrier to pass through and out, and a hot air blower 82 for providing heat and blowing heat to the preheating chamber 81. The hot air blower 82 is preferably arranged below the preheating chamber 81. The hot air blower and the preheating chamber constitute a rapid purge preheating station to pretreat the residual moisture of the catalyst carrier to be coated to prevent the initial weight of the carrier from increasing after absorbing moisture, thereby ensuring the accuracy and consistency of the coating.

[0057] The specific structure of the slurry supply device 1 is as follows: the slurry supply device 1 includes a slurry tank 11, a bracket 15 for supporting the slurry tank 11, and a flow meter 16 for measuring the flow of the slurry flowing therethrough. The flow meter 16 is provided to accurately measure the amount of slurry delivered to the coating chamber; a multi-layer high-efficiency stirring device 116 is provided in the slurry tank 11, which is conducive to uniform stirring of the slurry. The slurry tank 11 is provided with a plurality of slurry feed ports and a plurality of return ports. The feed port is connected to the feed pump through a pipeline, and the return port is connected to the return pump 14 through a pipeline. The pipeline is fixedly provided with a switching valve port with a standard interface, which can be automatically switched according to process requirements.

[0058] The outer surface of the slurry tank 11 is provided with a jacket layer 114, and a containing cavity is formed between the jacket layer 114 and the slurry tank 11, that is, the slurry tank 11 is composed of an inner and outer layer, the outer layer is the jacket layer 114 for containing water, and the inner layer is a cavity for storing slurry; a temperature sensor 115 extending into the slurry tank 11 is provided on the jacket layer 114. Cooling water or hot water can be passed into the jacket layer 114 to cool or heat the slurry in the tank. The cooling water or hot water is supplied and controlled by a pipeline and an automatic valve, and the temperature of the slurry in the slurry tank is kept stable.

[0059] The slurry tank 11 is also provided with a liquid level sensor 111, a density sensor and a viscosity sensor 113. The liquid level sensor 111 is used to detect the liquid level sensor 111 of the slurry capacity in the slurry tank 11. According to the detection data of the liquid level sensor 111, the feed pump and the automatic valve on the feed pipeline can be used to replenish the material to maintain the stability of the slurry capacity in the tank. The density sensor is used to detect the density of the slurry in the slurry tank 11, and the viscosity sensor 113 is used to detect the viscosity of the slurry in the slurry tank 11. When the density of the slurry in the tank increases, water is replenished through the water replenishment pump and the automatic valve on the water replenishment pipeline to maintain the stability of the slurry density in the tank. The viscosity sensor 113 monitors the viscosity of the slurry. Changes in the slurry temperature, density, concentration, etc. will bring about changes in viscosity. When the viscosity is stable, the slurry fluid properties remain consistent, and the consistency of the catalyst coating product is ultimately guaranteed.

[0060] The flow meter 16 is used to measure the amount of slurry delivered to the coating device 2. The flow meter 16 is extended into the slurry tank to detect the slurry liquid level. The flow meter 16 can accurately measure the amount of slurry delivered to the coating chamber, and control it through the coating valve (the slurry supply device 1 also includes a coating valve. When the volume of the slurry flowing through the flow meter 16 is within a preset first volume threshold range, the controller controls the coating valve to close), so that the coating amount each time remains constant, and ultimately ensures the consistency of the catalyst coating product; and replenishes the material through the feed pump and the automatic valve on the feed pipeline to maintain the stability of the slurry capacity in the tank.

[0061] The slurry supply device 1 also includes a delivery pump 12 and a pressure-stabilizing valve 13. The delivery pump 12 is used to deliver the slurry in the slurry tank 11 to the upper coating chamber or the lower coating chamber through a connecting hose 17. The pressure-stabilizing valve 13 is arranged at the end of the outlet pipe of the delivery pump 12. The pressure-stabilizing valve 13 is used to balance the delivery pressure pulse of the delivery pump 12. The interior of the pressure-stabilizing valve 13 is a layer of halo polytetrafluoroethylene diaphragm, and the diaphragm is connected to the valve core. There is slurry on one side of the diaphragm and compressed air for pressure stabilization on the other side. When the slurry pressure in the pipeline increases, the pressure pulse pushes the diaphragm to open the valve core, and the excess pressure is released due to the expansion of the volume in the valve; on the contrary, when the slurry pressure decreases, the compressed air pushes the diaphragm to close the valve core and the slurry pressure rises again. The regulating function of the pressure-stabilizing valve 13 can keep the working pressure in the coating chamber stable for a long time.

[0062] The upper coating chamber and the lower coating chamber are both connected to the slurry tank 11, and the automatic coating system has a coating state. When the automatic coating system is in the coating state, the upper coating chamber and the lower coating chamber are arranged in a one-to-one correspondence, and there is a space for accommodating the catalyst carrier between the two. The slurry tank 11 transports slurry to the catalyst carrier through the upper coating chamber or the lower coating chamber; the lower coating chamber is fixed on the operating table, and the upper coating chamber can be moved to the lower coating chamber with the mechanical claw, so that the upper coating chamber and the lower coating chamber are arranged in a one-to-one correspondence.

[0063] The upper coating chamber includes an upper coating station, see Figure 5 , the upper coating platform is provided with an upper cavity 211 for accommodating one end of the catalyst carrier, and the upper coating platform is provided with a groove with an opening facing downward to form the upper cavity 211 of the catalyst carrier. The cross-section of the groove can be circular, square or other shapes that match the catalyst carrier; the inner wall of the upper cavity 211 is provided with an annular screen 212 and a first sealing ring 213 arranged below the screen 212, the first sealing ring is an inflatable sealing ring, the first sealing ring 213 is arranged along the outer side wall of the upper cavity 211, and it is a hollow structure, the first sealing ring 213 has a clamping state, when in the clamping state, it can clamp the catalyst carrier to limit its detachment, when one end of the catalyst carrier is arranged below the first sealing ring 213, the upper cavity 211 and the upper end of the catalyst carrier form a space that can accommodate slurry, the upper cavity 211 is connected to the slurry tank 11 through the connecting hose 17, so that the slurry in the slurry tank 11 can enter the space, the slurry entry direction see Figure 5 The arrow pointed by a in the middle.

[0064] The upper coating chamber further comprises a first coating valve 214, a material level switch 216, and a first air source control valve 215. When the catalyst carrier is fed into the coating chamber, compressed air is fed into the first sealing ring by the first air source control valve 215 (see the compressed air entry direction). Figure 5b in the figure), the first sealing ring expands to firmly clamp the catalyst carrier and seal the edge of the carrier. When the first coating valve 214 is opened, the slurry is first buffered in the space formed by the upper cavity 211 and the upper end of the catalyst carrier, and the coating valve is closed after the flowmeter 16 measures and reaches the preset first capacity threshold range. Due to the viscosity and surface tension of the slurry, the slurry floats on the screen (the screen is an annular mesh component with multiple filter holes. It is very important to set the screen, which plays a buffering role and allows the slurry to enter the pores of the catalyst carrier more evenly). Then the vacuum suction valve 223 of the lower coating cavity is opened, and the slurry is vacuum-sucked into the interior of the catalyst carrier, so that the slurry can adhere to the inner wall of the catalyst carrier, realize the predetermined coating process, and realize that the uniformity of the height and thickness of the slurry coating in the pores of the catalyst carrier are optimized; the material level switch 216 can prevent unexpected situations such as slurry overflow after the flowmeter 16 detects errors.

[0065] The lower coating chamber includes a lower coating station, see Figure 6 The lower coating platform is provided with a lower cavity 221 for accommodating the other end of the catalyst carrier. The lower coating platform is provided with an upwardly opened groove to form a lower cavity 221 for accommodating one end of the catalyst carrier. The cross-section of the groove can be circular, square or other shapes that match the catalyst carrier. The bottom of the groove is provided with a pipe connected to the slurry tank; the outer wall of the lower cavity 221 is provided with a second sealing ring 222 of a hollow structure. The second sealing ring 222 is an inflatable sealing ring. The second sealing ring 222 has a clamping state. The first sealing ring 213 and the second sealing ring 222 are used to synchronously clamp the catalyst carrier when the catalyst carrier is arranged between the upper cavity 211 and the lower cavity 221. The lower cavity 221 and the lower end of the catalyst carrier form a space that can accommodate slurry. The lower cavity 221 is connected to the slurry tank 11 through a connecting hose 17, so that the slurry in the slurry tank 11 can enter the space. For the direction of slurry entry, refer to Figure 6 The arrow pointed to by d in the middle.

[0066] The lower coating chamber also includes a second coating valve 224, a vacuum suction valve 223, and a second air source control valve 225. When the catalyst carrier is fed into the lower coating chamber, compressed air is fed into the second sealing ring by the second air source control valve 225 (see the slurry entry direction). Figure 6(arrow indicated by c in the middle), the second sealing ring expands to firmly clamp the catalyst carrier and seal the outer peripheral edge of the carrier. When the second coating valve 224 is opened, the vacuum suction valve 223 is closed, and the slurry enters the lower coating cavity. The slurry pipeline pressure forces the slurry to flow from bottom to top through the interior of the carrier, and is measured by the aforementioned flow meter 16 and the second coating valve 224 is closed after reaching the preset first capacity threshold range. The slurry is first buffered in the space formed by the lower cavity 221 and the lower end of the catalyst carrier, and then the vacuum suction valve 223 of the lower coating cavity is opened, and the slurry is vacuum-sucked into the interior of the catalyst carrier, so that the slurry can adhere to the inner wall of the catalyst carrier; if the slurry exceeds the preset first capacity threshold range, the slurry in the lower coating cavity and the carrier is vacuum-sucked into the vacuum tank, and the excess slurry is discharged.

[0067] According to the viscosity of different slurries, the density of filter holes in the catalyst carrier or the coating ratio, choose to use the upper coating chamber or the lower coating chamber for coating. Usually, the upper coating chamber and the lower coating chamber do not need to work at the same time. For example, if the viscosity of the slurry is high, choose the upper coating chamber for coating; on the contrary, if the viscosity of the slurry is low, or the carrier mesh number is high, it is better to choose the lower coating chamber for coating. The advantage of choosing the lower coating chamber is that it is easy to carry out half-proportion coating (short for half coating, that is, only part of the inner wall is coated with slurry relative to the full coating) or partial coating, and there will be no pore blocking after uneven coating surface; in addition, slurry with low viscosity is easy to be evenly coated on the carrier of special materials, and its use is wider.

[0068] The sucking device 3 is used to suck back the slurry in the lower coating chamber, and the sucking device 3 includes a vacuum tank 31 connected to the lower coating chamber, a vacuum pump 32 connected to the vacuum tank 31, and a vacuum sensor 33 for measuring the vacuum degree of the vacuum tank. The vacuum pump is driven by a variable frequency motor, and maintaining a specific motor frequency can establish and maintain a stable vacuum degree, so that the change of the vacuum degree during the coating process remains consistent.

[0069] The first weighing device 5 is used to measure the original weight of the catalyst carrier to be coated with the slurry, and the second weighing device 6 is used to weigh the catalyst carrier after the first coating to obtain a first weight, and determine the weight of the slurry in the catalyst carrier after the first coating according to the difference between the original weight of the catalyst carrier and the first weight; the weighing device also includes a third weighing device 7, and the third weighing device 7 is used to weigh the catalyst carrier after the second coating to obtain a second weight, and determine the weight of the slurry in the catalyst carrier after the second coating according to the difference between the original weight of the catalyst carrier and the second weight. The first weighing device, the second weighing device and the third weighing device all have a variety of structural forms, as long as they can achieve weighing.

[0070] The transfer device 4 is used to transfer the catalyst carrier to different coating chambers and weighing devices. In an embodiment provided by the present invention, the transfer device 4 includes a mechanical arm 41, a drag chain 42 arranged on the mechanical arm 41, a driving mechanism 43 for driving the drag chain 42 to move, and a plurality of mechanical claws 44. Each mechanical claw 44 is connected to the drag chain 42 through a connecting piece. Under the drive of the driving mechanism 43, the drag chain 42 moves to drive the mechanical claw 44 to move; a mechanical claw 44 can be fixedly connected to an upper coating chamber so that the upper coating chamber can move with the mechanical claw 44. Not all mechanical claws 44 are provided with an upper coating chamber. In an embodiment provided by the present invention, two mechanical claws are respectively fixedly provided with an upper coating chamber; or only one mechanical claw is fixedly provided with an upper coating chamber.

[0071] The transfer device 4 has various structural forms, as long as it can grab the catalyst carrier, and is not limited to the above-mentioned specific structural forms.

[0072] In one embodiment of the present invention, the upper coating chamber includes a first upper coating chamber 24 and a second upper coating chamber 26, the lower coating chamber includes a first lower coating chamber 25 arranged opposite to the first upper coating chamber 24 when the slurry is coated once, and a second lower coating chamber 27 arranged opposite to the second upper coating chamber 26 when the slurry is coated twice, the drying device, the first weighing device 5, the first lower coating chamber 25, the second weighing device 6, the second lower coating chamber 27 and the third weighing device 7 are arranged side by side in sequence on the same horizontal support platform, the drying device is the first station, the first weighing device 5 is the second station, the first lower coating chamber 25 is the third station, the second weighing device 6 is the fourth station, the second lower coating chamber 27 is the fifth station, and the third weighing device 7 is the sixth station. The automatic coating system includes a first mechanical claw arranged above the drying device, a second mechanical claw arranged above the first weighing device 5, a third mechanical claw arranged above the first lower coating chamber 25, a fourth mechanical claw arranged above the second weighing device 6, a fifth mechanical claw arranged above the second lower coating chamber 27, and a sixth mechanical claw arranged above the third weighing device 7. The first upper coating chamber 24 is fixedly arranged on the third mechanical claw, and the second upper coating chamber 26 is fixedly arranged on the fifth mechanical claw.

[0073] The transfer device 4 is used to grab the catalyst carrier and make it pass through different stations in the coating order, including preheating using a drying device), pre-weighing (using a first weighing device), one coating, one weighing (using a second weighing device), two coatings, and two weighing (using a third weighing device), to finally complete the entire catalyst coating process.

[0074] The specific coating process is as follows:

[0075] Step 1: placing the catalyst carrier to be coated in the preheating chamber 81 of the drying device 8, and starting the hot air blower 82 to dry the moisture in the catalyst carrier;

[0076] Step 2: The first mechanical claw grabs the catalyst carrier and moves it to the first weighing device 1 for weighing to obtain the initial weight of the catalyst carrier. The first mechanical claw returns to the initial position. Then, the second mechanical claw grabs the weighed catalyst carrier and moves it to the first lower coating cavity 25. The second mechanical claw returns to the initial position.

[0077] Step 3: After the first upper coating cavity 24 on the third mechanical claw moves to above the first lower coating cavity 25, the first lower coating cavity 25 clamps the upper end of the catalyst carrier, and the first lower coating cavity 25 clamps the lower end of the catalyst carrier;

[0078] Step 4: Start the first upper coating chamber 24 or the first lower coating chamber 25 to coat the catalyst carrier with the slurry once, and when the coating amount is within the preset first capacity threshold range, close the coating chamber, and then the third mechanical claw moves the once coated catalyst carrier to the second weighing device 6 (the third mechanical claw returns to the initial position), and weighs the once coated catalyst carrier to obtain the first weight of the catalyst carrier;

[0079] Step 5: Determine whether the first weight of the catalyst carrier after the first coating is within the qualified range. In the first case, if yes, the weight of the catalyst carrier is qualified. In the second case, if the first weight of the catalyst carrier after the first coating is less than the preset qualified weight, a second coating is required, and step 6 is performed. In the third case, if the first weight of the catalyst carrier after the first coating is greater than the preset qualified weight, it is necessary to suck out excess slurry, and step 8 is performed.

[0080] Step 6: Calculate the preset second capacity threshold range of the slurry required for secondary coating, then the fourth manipulator grabs the catalyst carrier and moves it to the second lower coating chamber 27, the fourth manipulator returns to the initial position, the catalyst carrier is in the second lower coating chamber 27, the fifth manipulator and the second upper coating chamber 26 move to the second lower coating chamber 27, the second upper coating chamber 26 clamps the upper end of the catalyst carrier, the second lower coating chamber 27 clamps the lower end of the catalyst carrier, the second upper coating chamber 26 or the second lower coating chamber 27 is started, and the preset second capacity threshold range slurry is coated into the catalyst carrier;

[0081] After coating the slurry, the coating chamber is closed, and the fifth manipulator grabs the catalyst carrier after the second coating and moves it to the third weighing device 6. The fifth manipulator and the second upper coating chamber 26 return to the initial position, and the catalyst carrier after the second coating is weighed by the third weighing device to obtain the second weight of the catalyst carrier;

[0082] Step 7: Determine whether the second weight of the catalyst carrier after the second coating in step 6 is within the preset qualified range. If so, the weight of the catalyst carrier after coating is qualified; if not, if the second weight is less than the preset qualified weight, then perform the coating step and the weighing step in sequence until the weight of the catalyst carrier is within the qualified range. Usually, it is preferred to coat twice, because the slurry will dry in a shorter time, and multiple coatings will affect the slurry properties and waste the slurry. If only two coatings are required, the weight of the catalyst carrier after coating can also be determined to be unqualified in this step, and the deviation percentage of the unqualified weight is calculated, and the slurry required for the second coating in step 6 is adjusted according to the preset calculation formula;

[0083] Step 8, opening the back-sucking device to discharge the slurry exceeding the preset qualified range, and then using the third weighing device to measure the weight of the catalyst carrier after the slurry is discharged to obtain a third weight;

[0084] Step 9, determine whether the third weight of the catalyst carrier after discharging the slurry in step 8 is within the preset qualified range. If so, the weight of the coated catalyst carrier is qualified; if not, the weight of the catalyst carrier is unqualified, and the deviation percentage of the unqualified weight is calculated, and the operating parameters of the back-absorption device in step 8 are adjusted according to the preset calculation formula.

[0085] During the entire coating process, the catalyst carrier moves with the robot to different workstations.

[0086] Each mechanical claw has an initial position and a working position, and the initial position and the working position are arranged adjacent to each other.

[0087] The present invention also provides a coating process based on an automatic catalyst slurry coating system. If there are two coating opportunities, the slurries for the two coatings enter the catalyst carrier through two different upper coating chambers respectively; or the slurries for the two coatings enter the catalyst carrier through two different lower coating chambers respectively; or the slurries for the first coating first enter the catalyst carrier through the upper coating chamber, and the slurries for the second coating enter the catalyst carrier through the lower coating chamber; or the slurries for the first coating first enter the catalyst carrier through the lower coating chamber, and the slurries for the second coating enter the catalyst carrier through the upper coating chamber. If the catalyst carrier reaches the qualified weight after one coating, there is no need to coat the slurry for the second time. If two coatings are required, that is, in the above steps 4 and 6, the slurry can be allowed to enter the catalyst carrier through the upper coating chamber or the lower coating chamber respectively.

[0088] The double coating process provided by the present invention comprises the following steps, see Figure 8 :

[0089] S1, setting a preset first capacity threshold range for coating slurry, and setting a preset qualified weight (expected weight) and qualified range (i.e., within a deviation range) of the catalyst carrier;

[0090] S2, a first weighing device measures the original weight of the catalyst carrier before coating;

[0091] S3, the slurry enters the catalyst carrier for a first coating, and the second weighing device measures a first weight of the catalyst carrier after the first coating;

[0092] S4, judging whether the first weight of the catalyst carrier after the first coating is within the preset qualified weight range, if not, executing step S5; if yes, the weight of the catalyst carrier is qualified, ignoring step S5, and the catalyst carrier is transported to the next station;

[0093] S5, calculating the difference between the qualified weight and the first weight, if the difference is zero, the weight of the catalyst carrier is qualified; if the difference is positive, that is, the first weight is lower than the qualified weight, then executing step S6; if the difference is negative, that is, the first weight is higher than the qualified weight, then executing step S8;

[0094] S6, calculating a preset second capacity threshold range of the slurry required for the secondary coating, injecting the preset capacity of the slurry into the catalyst carrier for secondary coating, and then using a third weighing device to measure the weight of the catalyst carrier after the two coatings to obtain a second weight;

[0095] S7, judging whether the second weight of the catalyst carrier after the secondary coating in step S6 is within the preset qualified range, if so, the weight of the catalyst carrier after coating is qualified; if not, the weight of the catalyst carrier after coating is unqualified, and the deviation percentage of the unqualified weight is calculated, and the slurry required for the secondary coating in step S6 is adjusted according to the preset calculation formula; the purpose of adjusting the parameters is to make the next product reach the predetermined qualified weight range, and the unqualified products marked here will be eliminated in the subsequent device;

[0096] S8, turning on the back-sucking device to discharge the slurry exceeding the preset qualified range (the specific process of the back-sucking is as follows: opening the vacuum suction valve, the slurry in the lower coating cavity and the carrier is vacuum-sucked into the vacuum tank, thereby sucking back and discharging the slurry exceeding the preset first capacity threshold range), and then using the third weighing device to measure the weight of the catalyst carrier after the slurry is discharged to obtain a third weight;

[0097] S9, judging whether the third weight of the catalyst carrier after discharging the slurry in step S8 is within the preset qualified range, if so, the weight of the catalyst carrier after coating is qualified; if not, the weight of the catalyst carrier is unqualified, and the deviation percentage of the unqualified weight is calculated, and the operating parameters of the re-absorption device in step S8 are adjusted according to the preset calculation formula; the purpose of adjusting the parameters is to make the next product reach the preset qualified weight range. The unqualified products marked here will be eliminated in the subsequent devices.

[0098] The above calculation method is based on the standard size of the carrier, standard first weight, standard mesh value, actual first weight, actual second weight, actual third weight, preset coating pressure, flow rate, coating time, coating suction time, coating suction vacuum and other parameters.

[0099] The coating process of the catalyst slurry automatic coating system provided by the present invention selects an optimized coating method and coating process according to the viscosity of different slurries or the mesh number of catalyst carriers or the coating ratio, so as to achieve the uniformity and accuracy of the slurry in the catalyst carrier: for example, if the viscosity of the slurry is large, or the mesh number of the catalyst carrier is low (for example, below 500 mesh), or it is fully coated (the inner wall of the pores of the entire catalyst carrier is fully covered with the catalyst slurry), it is best to adopt the upper coating method; if the viscosity of the slurry is relatively large (for example, the viscosity is above 400cp), the upper coating cavity is selected to be started, and the slurry enters the catalyst carrier from top to bottom through the upper coating cavity; if the mesh number of the catalyst carrier is small (for example, below 500 mesh), or the catalyst carrier needs to be fully coated, the upper coating method is adopted, and the uniformity and accuracy of the slurry in the catalyst carrier are higher than the lower coating method.

[0100] If the viscosity of the slurry is small, or the catalyst carrier has a high mesh number, or partial area coating is required, the lower coating method is adopted, and the slurry enters the catalyst carrier from bottom to top through the lower coating cavity. If the viscosity of the slurry is small (for example, the viscosity is below 400cp), the lower coating method is adopted. Even if the catalyst carrier has a large mesh number (for example, more than 500 mesh), when the catalyst carrier needs to be regionally coated, the uniformity and accuracy of the slurry in the catalyst carrier are better than the upper coating method when the lower coating method is selected.

[0101] There is no mandatory selection standard for the upper coating method and the lower coating method. Different catalyst slurry viscosities, catalyst carrier mesh sizes, coating ratios and other conditions will result in different deviations in the coating weight when selecting the upper coating method or the lower coating method. Therefore, choosing a suitable coating method can effectively improve the uniformity and accuracy of the slurry in the catalyst carrier.

[0102] Under the same environmental conditions, the same catalyst carrier is coated with the same slurry of the same capacity (for example, a three-way catalyst TWC). Before coating, the coating tank is sampled and the average coating amount is measured in winter and summer using the traditional process (using a single lower coating method). The average coating amount is shown in Table 1. The coating tank is sampled and the average coating amount is measured in winter and summer using the traditional process (using a single upper coating method). The test results of the coating process provided by the present invention are shown in Table 3. The standard properties of the slurry are measured as follows: Ambient temperature: The indoor temperature of the coating workshop is 5 degrees in winter and 35 degrees in summer. The solid content is 43%, the viscosity is 1489cp, and the theoretical coating weight is 550g. The quality control qualification requirement for coating accuracy is not less than 2% of the coating weight. If the coating amount is too much, it will have little effect on the catalyst performance quality, but it will increase the production cost. Using the traditional process (using a single upper coating method), it is impossible to complete the catalyst carriers such as DPF (diesel particulate trap) and GPF (gasoline particulate trap) and the regional coating process with high quality, so no comparison is made here.

[0103] Table 1 Test results of catalyst carriers coated with slurry using a single coating method

[0104]

[0105]

[0106] Table 2 Test results of catalyst carriers coated with slurry using a single coating method

[0107]

[0108] Table 3 Test results of the catalyst carrier coated with slurry using the coating process provided by the present invention

[0109]

[0110] It can be seen from Tables 1, 2 and 3 above that unqualified products are prone to occur when a single upper coating method or a single lower coating method is used, and the traditional method cannot adjust the key parameters of the slurry such as temperature, viscosity, solid content, and conveying pressure pulsation. Therefore, it is impossible to ensure the uniformity of the slurry characteristics at different temperatures in different seasons, thereby affecting the final coating effect. Among them, all experiments are carried out at the same ambient temperature, such as 5 degrees in winter and 35 degrees in summer. The different slurry characteristics mean that the temperature, viscosity, solid content, conveying pressure pulsation, etc. cannot be adjusted in the traditional process, and the slurry characteristics cannot meet the requirements. In the present invention, the slurry characteristics can be adjusted, and the uniformity of the coating height of the slurry on the inner wall of the catalyst carrier pore can be controlled through detection to achieve the optimal state of the slurry theoretical standard.

[0111] The coating device and coating process involved in the present invention solve the problems of the traditional coating process, such as the complicated operation process, the need for a large number of manual changeover operations, the long coating changeover time and low efficiency; it also solves the problems of uniformity and repeatability of the coating process, thereby enhancing the consistency of the catalyst product and meeting the strict quality management standards of the automotive industry and the environmental protection industry; at the same time, due to the large changes in the physical properties of the National VI catalyst coating raw materials, the demand for regional coating has increased significantly, and the fully automatic coating process of the present invention can greatly enhance the reliability of regional coating (semi-coating); keep the coating amount constant each time, and ultimately ensure the consistency of the catalyst coating product; by setting different flow values ​​for regional coating, the coating range of the regional coating can be accurately controlled to meet the production consistency and repeatability of the product.

[0112] The coating device of the present invention integrates the upper coating chamber and the lower coating chamber together, and can be selected according to the characteristics of the slurry to be coated, and can be used to coat different catalyst carriers with catalyst slurry, which is universal and can meet different needs; by setting a temperature sensor, a liquid level sensor, a density sensor and a viscosity sensor, the uniformity, consistency and accuracy of the catalyst slurry in the entire coating process can be effectively controlled to avoid deviations in temperature, viscosity, density and concentration of the slurry before and after the entire coating process. The coating process of the present invention can be selected according to the characteristics of the slurry to be coated, and the catalyst slurry coating can be completed in a relatively short time, and the process deviation can be automatically corrected, and material leakage and loss can be reduced to improve production efficiency, and the operation is simple.

[0113] Depending on the different models and engine characteristics, the carrier size and specifications are not the same. At the same time, even for carriers of the same size and specifications, the components and characteristics of the catalyst coating slurry used are different due to the different combustion conditions of the engines of various car companies. For catalyst manufacturers, the adjustment of the production line when producing the above-mentioned different carriers and components is to change the model. The coating device and coating process involved in the present invention are fully suitable for automatic coating of carriers of multiple varieties and characteristics, which can meet the production change of multiple catalysts; the equipment has a compact structure and fully automated operation, which can maximize the utilization of equipment production capacity requirements; the unique fully enclosed design reduces material leakage and loss; the coating process involved in the present invention can automatically correct the deviation of the coating slurry, making the setting of coating parameters simpler and more intuitive, and reducing the quality risk of new product research and development.

[0114] 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 coating process of a catalyst slurry automatic coating system, characterized in that: Including two coating processes, which means that the slurry of the two coatings enters the catalyst carrier through two different upper coating chambers respectively; or the slurry of the two coatings enters the catalyst carrier through two different lower coating chambers respectively; or the slurry of the first coating first enters the catalyst carrier through the upper coating chamber, and the slurry of the second coating enters the catalyst carrier through the lower coating chamber; or the slurry of the first coating first enters the catalyst carrier through the lower coating chamber, and the slurry of the second coating enters the catalyst carrier through the upper coating chamber; The two-coating process comprises the following steps: S1, setting a preset first capacity threshold range of the slurry to be coated and a preset qualified weight and qualified range of the catalyst carrier; S2, a first weighing device measures the original weight of the catalyst carrier before coating; S3, the slurry enters the catalyst carrier for a coating, and a second weighing device measures the first weight of the catalyst carrier after the coating; S4, judging whether the first weight of the catalyst carrier after the first coating is within the qualified range, if not, executing step S5; if yes, the weight of the catalyst carrier is qualified; S5, calculating the difference between the qualified weight and the first weight, if the difference is zero, the weight of the catalyst carrier is qualified; if the difference is positive, that is, the first weight is lower than the qualified weight, then executing step S6; if the difference is negative, that is, the first weight is higher than the qualified weight, then executing step S8; S6, calculating a preset second capacity threshold range of the slurry required for the secondary coating, the slurry enters the catalyst carrier for secondary coating, and then using a third weighing device to measure the weight of the catalyst carrier after the two coatings to obtain a second weight; S7, judging whether the second weight of the catalyst carrier after the secondary coating in step S6 is within the preset qualified range, if so, the weight of the catalyst carrier after coating is qualified; if not, the weight of the catalyst carrier after coating is unqualified, and calculating the deviation percentage of the unqualified weight, and adjusting the slurry required for the secondary coating in step S6 according to the preset calculation formula; S8, opening the back-sucking device to discharge the slurry exceeding the preset qualified range, and then using the third weighing device to measure the weight of the catalyst carrier after the slurry is discharged to obtain a third weight; S9, judging whether the third weight of the catalyst carrier after the slurry is discharged in step S8 is within a preset qualified range, if so, the weight of the catalyst carrier after coating is qualified; if not, the weight of the catalyst carrier is unqualified, and the deviation percentage of the unqualified weight is calculated, and the operating parameters of the back-absorption device in step S8 are adjusted according to the preset calculation formula; The catalyst slurry automatic coating system is used to coat the catalyst slurry into a catalyst carrier, the coating system comprising a slurry supply device (1), one or more upper coating chambers, one or more lower coating chambers, a back-sucking device (3) connected to the lower coating chamber, a transfer device (4) for transferring the catalyst carrier, a first weighing device (5) for measuring the weight of the catalyst carrier, a second weighing device (6) and a third weighing device (7); The slurry supply device (1) comprises a slurry tank (11) and a flow meter (16), wherein the flow meter (16) is used to measure the volume of slurry transported from the slurry tank (11) to the upper coating chamber or the lower coating chamber; The upper coating chamber and the lower coating chamber are both connected to a slurry tank (11), and the automatic coating system has a coating state. When in the coating state, the upper coating chamber and the lower coating chamber are arranged in a one-to-one correspondence, and there is a space for accommodating a catalyst carrier between the two. The slurry tank (11) transports slurry to the catalyst carrier through the upper coating chamber or the lower coating chamber; The first weighing device (5) and the second weighing device (6) are respectively arranged on both sides of a lower coating cavity, the first weighing device (5) is used to measure the original weight of the catalyst carrier to be coated with slurry, and the second weighing device (6) is used to measure the weight of the catalyst carrier after the slurry is coated once; the third weighing device (7) and the second weighing device (6) are arranged on both sides of another lower coating cavity, and are used to measure the weight of the catalyst carrier after the slurry is coated twice; The suction device (3) is used to discharge the slurry from the lower coating chamber.

2. The coating process of the catalyst slurry automatic coating system according to claim 1 is characterized in that: The upper coating chamber comprises an upper coating platform, an upper cavity (211) for accommodating one end of a catalyst carrier is provided on the upper coating platform, an annular screen (212) and a first sealing ring (213) arranged below the screen (212) are arranged on the inner wall of the upper cavity (211), and the first sealing ring (213) is arranged along the outer wall of the upper cavity (211); The lower coating chamber comprises a lower coating platform, on which a lower cavity (221) for accommodating the other end of a catalyst carrier is provided, and an outer side wall of the lower cavity (221) is provided with a second sealing ring (222) with a hollow structure, and the first sealing ring (213) and the second sealing ring (222) are used for synchronously clamping the catalyst carrier when the catalyst carrier is arranged between the upper cavity (211) and the corresponding lower cavity (221).

3. The coating process of the catalyst slurry automatic coating system according to claim 1 is characterized in that: The upper coating chamber comprises a first upper coating chamber (24) and a second upper coating chamber (26); the lower coating chamber comprises a first lower coating chamber (25) arranged opposite to the first upper coating chamber (24) when the slurry is coated once, and a second lower coating chamber (27) arranged opposite to the second upper coating chamber (26) when the slurry is coated twice; the first weighing device (5), the first lower coating chamber (25), the second weighing device (6), the second lower coating chamber (27) and the third weighing device (7) are arranged side by side in sequence.

4. The coating process of the catalyst slurry automatic coating system according to claim 1 is characterized in that: The slurry tank (11) is provided with a stirring device (116), and the slurry tank (11) is provided with a plurality of slurry feed ports (112) and a plurality of return ports, the feed port (112) being connected to a feed pump via a pipeline, and the return port being connected to a return pump (14) via a pipeline, and the pipelines are both fixedly provided with switching valve ports; the outer surface of the slurry tank (11) is provided with a jacket layer (114), a containing cavity is formed between the jacket layer (114) and the slurry tank (11), and the jacket layer (114) is provided with a temperature sensor (115) capable of extending into the slurry tank (11).

5. The coating process of the catalyst slurry automatic coating system according to claim 1 is characterized in that: The slurry tank (11) is also provided with a liquid level sensor (111), a density sensor and a viscosity sensor (113); the liquid level sensor (111) is used to detect the volume of the slurry in the slurry tank (11); the density sensor is used to detect the density of the slurry in the slurry tank (11); and the viscosity sensor (113) is used to detect the viscosity of the slurry in the slurry tank (11).

6. The coating process of the catalyst slurry automatic coating system according to claim 1, characterized in that: The catalyst slurry automatic coating system further comprises a drying device (8) for heating a catalyst carrier to be coated with the slurry, wherein the drying device (8) comprises a preheating chamber (81) for accommodating the catalyst carrier and a hot air blower (82) for providing heat and blowing the heat toward the preheating chamber (81).

7. The coating process of the catalyst slurry automatic coating system according to claim 1, characterized in that: The slurry supply device (1) further comprises a delivery pump (12) and a pressure-stabilizing valve (13); the delivery pump (12) is used to deliver the slurry in the slurry tank (11) to the upper coating chamber or the lower coating chamber via a connecting hose (17); the pressure-stabilizing valve (13) is arranged at the end of the outlet pipe of the delivery pump (12); the back-sucking device (3) comprises a vacuum tank (31) connected to the lower coating chamber and a vacuum pump (32) connected to the vacuum tank (31); The transfer device (4) comprises a mechanical arm (41), a drag chain (42) arranged on the mechanical arm (41), a driving mechanism (43) for driving the drag chain (42) to move, and a plurality of mechanical claws (44); the movement of the drag chain (42) can drive the mechanical claws (44) to move; a mechanical claw (44) can be fixedly connected to an upper coating chamber, so that the upper coating chamber can move with the mechanical claw (44).

8. The coating process of the catalyst slurry automatic coating system according to claim 1, characterized in that: According to the viscosity of different catalyst slurries, the mesh size of catalyst carriers or the coating ratio, the optimized coating method can be selected. If the viscosity of the catalyst slurry is high, or the catalyst carrier has a low mesh number, or is fully coated, the slurry enters the catalyst carrier from top to bottom through the upper coating cavity, that is, the upper coating method is selected to obtain a product with optimized uniformity and accuracy; If the viscosity of the catalyst slurry is small, or the catalyst carrier has a high mesh number, or is partially coated, the slurry enters the catalyst carrier from bottom to top through the lower coating cavity, that is, the lower coating method is selected to obtain a product with optimized uniformity and accuracy.

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