Production process of SCR plate-type denitration catalyst

Abstract

The invention discloses a production process of an SCR plate-type denitration catalyst, and relates to the technical field of SCR plate-type denitration catalyst production, and the production process comprises the following steps: unreeling and welding treatment; carrying out primary deviation correction treatment; carrying out coating and rolling treatment; performing primary drying treatment; carrying out secondary deviation rectification and rolling treatment; performing secondary drying treatment; correcting for the third time, and rolling; rolling for the fourth time; flying shear treatment; according to the design, efficient butt welding can be conducted through the straight head welding machine when two rolls of stainless steel screen plate strips are unreeled, the unreeled continuity is effectively improved, then through precise multi-stage rolling control, raw material waste caused by machining errors can be reduced, the raw material utilization rate is increased, and the production cost is reduced; in addition, a four-stage rolling and two-stage drying mode or a three-stage rolling and two-stage drying mode is adopted, so that moisture of the catalyst coating can be effectively removed, the quality problems of coating cracking, bubbling and the like caused by moisture residues are prevented, and reliable product quality is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of SCR plate denitration catalyst production, and specifically to a production process of SCR plate denitration catalyst. Background Art

[0002] SCR plate denitration catalysts play an important role in the field of denitration. Through their unique structure and excellent catalytic performance, they effectively reduce NOx emissions. With the increasingly strict environmental protection regulations, SCR catalysts will continue to be widely used in multiple industrial fields and automotive emission control;

[0003] Stainless steel mesh belts are usually used as the support structure of catalyst carriers, which can fix the catalyst material in a suitable position to ensure the effectiveness and reaction efficiency of the catalyst. It provides mechanical support for the catalyst and keeps it in a suitable physical form so that gas can uniformly pass through the surface of the catalyst;

[0004] In the current production process of SCR plate denitration catalysts, there are still problems of low efficiency in continuous production processes. The continuous unwinding and connection fixation of stainless steel mesh belts are not perfect enough to effectively ensure the continuity of the production process, thus affecting production efficiency. Therefore, the present invention provides a production process of SCR plate denitration catalyst. Summary of the Invention

[0005] In view of the deficiencies of the prior art, the present invention provides a production process of SCR plate denitration catalyst, which solves the problems raised in the above background art.

[0006] To achieve the above objectives, the present invention is realized through the following technical solutions: A production process of SCR plate denitration catalyst, the production process includes the following steps:

[0007] Step 1: Unwinding and Welding Treatment

[0008] Use an uncoiler to unwind the coiled stainless steel mesh raw material in a stable and uniform state, and a straight-head welding machine can be used to straighten and weld the stainless steel mesh;

[0009] Step 2: Primary Deviation Correction Treatment

[0010] Use a first-level deviation corrector to adjust the tension on both sides of the welded stainless steel mesh, so that the stainless steel mesh always remains flat during operation;

[0011] Step 3: Coating and Rolling Treatment

[0012] The catalyst slurry is evenly coated on the surface of the stainless steel mesh plate through an extruder. Then, by means of the cooperative extrusion of the upper and lower rollers of the first-stage roller press, the catalyst coating is closely attached to the stainless steel mesh plate. At the same time, the coating on the stainless steel mesh plate is trimmed by a trimming machine to optimize the flatness of the stainless steel mesh plate;

[0013] Step Four: Primary drying treatment

[0014] The roller-pressed stainless steel mesh plate is dried by a first-stage drying furnace;

[0015] Step Five: Secondary alignment and rolling treatment

[0016] The dried stainless steel mesh plate is aligned by a second-stage tension alignment machine. After the alignment is completed, the stainless steel mesh plate is subjected to a secondary rolling operation by a second-stage roller press;

[0017] Step Six: Secondary drying treatment

[0018] The stainless steel mesh plate after secondary rolling is conveyed into a second-stage drying furnace for secondary drying treatment;

[0019] Step Seven: Tertiary alignment and rolling treatment

[0020] Again, the stainless steel mesh plate is aligned by a third-stage tension alignment machine, and then the stainless steel mesh plate is subjected to a third rolling operation by a third-stage roller press;

[0021] Step Eight: Fourth rolling treatment

[0022] Step Nine: Flying shear treatment

[0023] The roller-pressed stainless steel mesh plate is conveyed to a flying shear by a belt conveyor for sizing cutting of the stainless steel mesh plate;

[0024] Step Ten: Profiling treatment

[0025] The cut stainless steel mesh plate is conveyed to a special crankshaft press by a belt conveyor. The cut stainless steel mesh plate is subjected to a stamping and forming operation by the crankshaft press to finally form an SCR plate-type denitration catalyst plate body.

[0026] As a further technical solution of the present invention, in the step eight, the conditions for the fourth rolling treatment are as follows:

[0027] (1) If the third-stage rolling process is not cancelled, the stainless steel mesh plate rolled by the third-stage roller press is conveyed to a fourth-stage roller press by a belt conveyor, and the fourth-stage roller press is used for the last rolling. The rolling of the fourth-stage roller press mainly performs final fine adjustment on the thickness, flatness, and coating quality of the stainless steel mesh plate;

[0028] (2) If the three-stage roll pressing process is cancelled, it is directly conveyed to the subsequent flying shear by a belt conveyor for flying shear operation.

[0029] As a further technical solution of the present invention, the drying treatment steps of the primary drying furnace are as follows:

[0030] (1) First, pre-dry for 1-2 hours in a low-temperature environment of 50-60°C to initially remove most of the moisture in the catalyst coating;

[0031] (2) Then raise the temperature to 100-120°C and continue drying for 3-4 hours until the water content on the surface of the stainless steel mesh plate is lower than 1wt%.

[0032] As a further technical solution of the present invention, the tension control range of the primary tension rectifier is 500-800N;

[0033] The tension control of the secondary tension rectifier is 400-600N;

[0034] The tension control of the tertiary tension rectifier is 300-500N;

[0035] In addition, the rectification accuracy of the primary tension rectifier, secondary tension rectifier and tertiary tension rectifier is maintained at ±1mm.

[0036] As a further technical solution of the present invention, the roll pressing pressure of the primary roll press is stably controlled at 5-10MPa;

[0037] The roll pressing pressure of the secondary roll press is stably controlled at 6-12MPa;

[0038] The roll pressing pressure of the tertiary roll press is stably controlled at 8-15MPa;

[0039] The roll pressing pressure of the quaternary roll press is stably controlled at 10-20MPa;

[0040] In addition, the roll pressing speeds of the primary roll press, secondary roll press, tertiary roll press and quaternary roll press are all maintained at 5-8m / min.

[0041] As a further technical solution of the present invention, the drying conditions of the secondary drying furnace are: drying in a temperature range of 120-150°C for a drying time of 2-3 hours.

[0042] As a further technical solution of the present invention, the frequency of the flying shear is 5-10 times / min, and the dimensional accuracy of the cut stainless steel mesh plate is controlled within ±2mm.

[0043] As a further technical solution of the present invention, the stamping pressure of the crank press is 50-100MPa, and the stamping speed is 3-5 times / min.

[0044] As a further technical solution of the present invention, the straight-head welding machine in the first step includes a straight-head machine and a resistance welding machine, specifically:

[0045] (1) Straighten the head of the unfolded stainless steel mesh plate with a straight-head machine;

[0046] (2) For the stainless steel mesh plates that need to be spliced subsequently, perform welding operations with a resistance welding machine.

[0047] The present invention provides a production process for SCR plate denitration catalysts. Compared with the prior art, it has the following beneficial effects:

[0048] 1. A production process for SCR plate denitration catalysts can perform efficient butt welding when two rolls of stainless steel mesh belt are unrolled by a straight-head welding machine, effectively improving the continuity of unrolling. Secondly, through precise multi-stage roll pressing control, raw material waste caused by processing errors can be reduced, the utilization rate of raw materials can be improved, and production costs can be reduced.

[0049] 2. A production process for SCR plate denitration catalysts can adopt a 4-stage roll pressing and 2-stage drying method, or a 3-stage roll pressing and 2-stage drying method, which can make the catalyst coating firmly adhere to the steel plate, enhance the stability of the product during use, prevent the coating from falling off and affecting the catalytic effect, can effectively remove the moisture in the catalyst coating, prevent quality problems such as coating cracking and blistering caused by moisture residue, and ensure the reliable quality of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 It is a structural schematic diagram of a production process for SCR plate denitration catalysts.

[0051] In the figure: 1. Uncoiler; 2. Straight-head welding machine; 3. Extruder; 4. First-level tension rectifier; 5. First-level roll press; 6. Edge trimming machine; 7. First-level drying furnace; 8. Second-level tension rectifier; 9. Second-level roll press; 10. Second-level drying furnace; 12. Third-level tension rectifier; 13. Third-level roll press; 14. Belt conveyor; 15. Fourth-level roll press; 16. Flying shear; 17. Crank press. DETAILED DESCRIPTION OF THE INVENTION

[0052] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0053] Please refer to Figure 1As shown in the figure, the present invention provides a production process technical solution for an SCR plate denitration catalyst: A production process for an SCR plate denitration catalyst, and the specific production process flow is as follows:

[0054] Step 1: Uncoiling operation of the uncoiler;

[0055] Precisely place the coiled stainless steel mesh plate raw material on the uncoiler 1. The uncoiler 1 ensures that the stainless steel mesh plate unfolds in a stable and uniform state by regulating the unwinding speed. The unwinding speed of the uncoiler 1 is 5 - 10 m / min, effectively avoiding situations such as wrinkles and stretching deformation of the stainless steel mesh plate during the uncoiling process, providing a good raw material basis for subsequent processes;

[0056] It should be added that the width of the stainless steel mesh plate belt is less than 600 mm, the allowable maximum tension ≤ 100 Kgf, and the diagonal of the mesh hole is 2 × 4 mm.

[0057] Step 2: Straightening and welding operation;

[0058] Straighten the head of the unfolded stainless steel mesh plate with a straightener to ensure that it can smoothly enter the subsequent processing link. Then, for the stainless steel mesh plate that continues to unwind and needs to be spliced later, use a resistance welder for welding operations to ensure that the weld is firm and flat, without quality defects such as pores and cracks, thereby maintaining the overall strength and structural continuity of the stainless steel mesh plate;

[0059] For example: When a whole roll of stainless steel mesh plate belt runs out, the mesh belt head at the end of the belt is not neat, and at the same time, the head of another newly opened roll of stainless steel mesh plate belt (i.e., the head of the mesh plate belt) is also not neat. To ensure that the head of the newly opened roll of material can be neatly welded together with the head of the previous roll of material, it is necessary to cut the head and the end (i.e., the tail of the mesh plate belt) neatly. This cutting process is called "straightening". After cutting, the two neat heads are overlapped vertically and welded together with a resistance welder, so that the strip material can run continuously.

[0060] Step 3: Primary deviation correction treatment;

[0061] Continue to convey the above-mentioned welded stainless steel mesh plate into the first-stage tension deviation correction machine 4. The first-stage tension deviation correction machine 4 precisely adjusts the tension on both sides of the stainless steel mesh plate, so that the stainless steel mesh plate always maintains a flat state during operation, and the position is accurate;

[0062] Among them, the tension control range of the first-stage tension deviation correction machine 4 is 500 - 800 N, and the deviation correction accuracy can reach ±1 mm, effectively preventing the stainless steel mesh plate from running off track in subsequent processes, and effectively ensuring that the product quality is not affected.

[0063] Step 4: Catalyst layer coating treatment;

[0064] By starting the operation of the extruder 3, the catalyst slurry is evenly covered on the surface of the stainless steel mesh plate by using the extruder 3. Among them, the die head design of the extruder 3 can be customized according to the size of the stainless steel mesh plate and the thickness and shape of the required coating, ensuring that the extruded slurry can be evenly covered on the surface of the stainless steel plate.

[0065] Step Five: Primary roll press rolling treatment;

[0066] The coated stainless steel mesh plate continues to be conveyed into the primary roll press 5. By using the cooperative extrusion of the upper and lower rolls of the primary roll press 5, the catalyst coating is promoted to be closely attached to the stainless steel mesh plate. At the same time, the edge trimming machine 6 trims the coating on the stainless steel mesh plate, thereby optimizing the flatness of the stainless steel mesh plate;

[0067] It should be noted that: the rolling pressure of the primary roll press 5 is stably controlled at 5 - 10 MPa, and the rolling speed is synchronized with the production line speed, usually 5 - 8 m / min, so as to ensure that the coating is firmly attached to the stainless steel mesh plate. In addition, the stainless steel mesh plate is ensured not to be deformed, meeting the preliminary requirements of the production process for product quality.

[0068] Step Six: Primary drying treatment;

[0069] The stainless steel mesh plate treated by the primary roll press 5 enters the primary drying furnace 7 for drying treatment. Specifically:

[0070] ① First, the rolled stainless steel mesh plate is pre-dried for 1 - 2 hours in a low-temperature environment of 50 - 60 °C to initially remove most of the moisture in the catalyst coating;

[0071] ② Then the temperature is raised to 100 - 120 °C and drying continues for 3 - 4 hours until the water content on the surface of the stainless steel mesh plate is lower than 1 wt%; this process effectively guarantees the drying degree of the catalyst coating and makes full preparations for the smooth progress of subsequent processes.

[0072] Step Seven: Secondary tension adjustment treatment;

[0073] The dried stainless steel mesh plate is processed again by the secondary tension rectifier 8 to accurately correct the slight deformation or position deviation that may occur during the drying process of the stainless steel mesh plate;

[0074] It should be noted that in this process, the tension of the secondary tension rectifier 8 is controlled at 400 - 600 N, and the rectification accuracy is also maintained at ±1 mm, ensuring that the stainless steel mesh plate can enter the next process accurately and guaranteeing the continuity and stability of the production process.

[0075] Step Eight: Secondary roll press rolling treatment;

[0076] The secondary rolling operation is performed on the stainless steel mesh plate using the secondary rolling press 9, aiming to further strengthen the bonding strength between the catalyst coating and the stainless steel mesh plate, and at the same time, more precisely control the thickness and surface flatness of the stainless steel mesh plate;

[0077] It should be added that the rolling pressure of the secondary rolling press 9 can be flexibly adjusted within the range of 6 - 12 MPa according to actual production requirements, and the rolling speed remains at 5 - 8 m / min, strictly ensuring that the product quality meets the established standard requirements.

[0078] Step Nine: Secondary drying treatment;

[0079] After the secondary rolling, the stainless steel mesh plate continues to be conveyed into the secondary drying furnace 10 and dried for 2 - 3 hours within the temperature range of 120 - 150 °C. This process can not only further remove the possible residual trace moisture inside the catalyst coating but also make the structure of the catalyst coating more stable.

[0080] Step Ten: Tertiary tension adjustment treatment;

[0081] After the above steps, the tertiary tension rectifier 12 is used again to perform rectification operations on the stainless steel mesh plate to ensure the position accuracy of the stainless steel mesh plate in subsequent processes;

[0082] In this process, the tension of the tertiary tension rectifier 12 is controlled at 300 - 500 N, and the rectification accuracy is ±1 mm, creating good conditions for subsequent rolling and forming processes, and ensuring the accuracy and consistency of product production.

[0083] Step Eleven: Tertiary rolling treatment;

[0084] The tertiary rolling press 13 performs the third rolling on the stainless steel mesh plate to further optimize the surface quality of the stainless steel mesh plate and the bonding effect between the coating and the stainless steel mesh plate;

[0085] It should be added that the rolling pressure of the tertiary rolling press 13 is controlled at 8 - 15 MPa, and the rolling speed remains at 5 - 8 m / min. After three - time rolling treatment, the stainless steel mesh plate can reach the final product quality standard and meet the strict requirements of the market for product performance.

[0086] Step Twelve: Quaternary rolling treatment;

[0087] The specific conditions are as follows:

[0088] (1) If the tertiary rolling process is not cancelled, the stainless steel mesh plate rolled by the tertiary rolling press 13 is conveyed to the quaternary rolling press 15 through the belt conveyor 14, and the quaternary rolling press 15 performs the last rolling. The rolling of the quaternary rolling press 15 mainly makes final fine adjustments to the thickness, flatness, and coating quality of the stainless steel mesh plate;

[0089] (2) If the three - stage roll - pressing process is cancelled, it is directly conveyed to the subsequent flying shear 16 through the belt conveyor 14 for flying shear operation.

[0090] It should be added that: the conveying speed of the belt conveyor 14 is closely adapted to the production line speed, generally set at 6 - 10 m / min, ensuring the smooth operation of the stainless - steel mesh plate during conveying without abnormal situations such as collision and scratching, and guaranteeing the integrity of the product.

[0091] In addition, the roll - pressing pressure of the four - stage roll press 15 is 10 - 20 MPa, and the roll - pressing speed is maintained at 5 - 8 m / min to meet the high - precision quality requirements of the product.

[0092] Step Thirteen: Flying Shear Treatment;

[0093] (1) The roll - pressed stainless - steel mesh plate is conveyed to the flying shear 16 through the belt conveyor 14. During the conveying process, the speed of the belt conveyor 14 remains constant, ensuring that the stainless - steel mesh plate can be accurately cut by the flying shear 16, providing billets with dimensions meeting the requirements for the subsequent forming process.

[0094] (2) The flying shear 16 can perform sizing cutting on the stainless - steel mesh plate according to the preset size parameters, and the cutting speed can be reasonably adjusted according to the thickness and material properties of the stainless - steel mesh plate, basically 5 - 10 times / min, ensuring that the dimensional accuracy of the cut stainless - steel mesh plate is controlled within ±2 mm, fully meeting the product specification requirements and providing an accurate raw material basis for the forming processing of the product.

[0095] Step Fourteen: Pressing and Forming Treatment;

[0096] (1) The cut stainless - steel mesh plate is conveyed to the special crankshaft press 17 through the belt conveyor 14, and the conveying speed of the belt conveyor 14 is precisely matched with the cutting speed of the flying shear 16, ensuring that the stainless - steel mesh plate can enter the crankshaft press 17 for stamping and forming processing in a timely and accurate manner, guaranteeing the efficient connection of the production process.

[0097] (2) Then, the cut stainless - steel mesh plate is subjected to stamping and forming operations using the crankshaft press 17 to finally form the SCR plate - type denitration catalyst plate body.

[0098] It should be noted that the stamping pressure of the crankshaft press 17 can be flexibly adjusted within the range of 50 - 100 MPa, and the stamping speed is 3 - 5 times / min. By precisely controlling the stamping parameters, it is ensured that the formed catalyst plate body fully meets the designed shape and size requirements.

[0099] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0100] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A production process of an SCR plate-type denitration catalyst, characterized in that, The production process includes the following steps: Step 1: Unwinding and welding treatment Use the uncoiler (1) to unwind the coiled stainless steel mesh raw material in a stable and uniform state, and the straight-head welding machine (2) can be used to straighten and weld the stainless steel mesh. Step 2: Primary deviation correction treatment Use the first-level deviation correction machine (4) to adjust the tension on both sides of the welded stainless steel mesh, so that the stainless steel mesh always maintains a flat state during operation. Step 3: Coating and rolling treatment The catalyst slurry is evenly covered on the surface of the stainless steel mesh through the extruder (3), and then the combined extrusion of the upper and lower rollers of the first-level rolling machine (5) is used to promote the close fit of the catalyst coating and the stainless steel mesh. At the same time, the edge trimming machine (6) trims the coating on the stainless steel mesh to optimize the flatness of the stainless steel mesh. Step 4: Primary drying treatment Use the first-level drying furnace (7) to dry the rolled stainless steel mesh. Step 5: Secondary deviation correction and rolling treatment Use the second-level tension deviation correction machine (8) to correct the dried stainless steel mesh. After the deviation correction is completed, use the second-level rolling machine (9) to perform secondary rolling on the stainless steel mesh. Step 6: Secondary drying treatment Transfer the stainless steel mesh after secondary rolling into the second-level drying furnace (10) for secondary drying treatment. Step 7: Tertiary deviation correction and rolling treatment Use the third-level tension deviation correction machine (12) to perform deviation correction on the stainless steel mesh again, and then use the third-level rolling machine (13) to perform the third rolling operation on the stainless steel mesh. Step 8: Quaternary rolling treatment Step 9: Flying shear treatment The rolled stainless steel mesh is transported to the flying shear machine (16) through the belt conveyor (14) for sizing cutting of the stainless steel mesh. Step 10: Profiling treatment The cut stainless steel mesh is transported to the special crankshaft press (17) through the belt conveyor (14), and the crankshaft press (17) is used to perform stamping forming on the cut stainless steel mesh to finally form the SCR plate type denitration catalyst plate.

2. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, In the above step 8, the conditions for the quaternary rolling treatment are as follows: (1) If the tertiary rolling process is not cancelled, the stainless steel mesh rolled by the third-level rolling machine (13) is transported to the fourth-level rolling machine (15) through the belt conveyor (14), and the fourth-level rolling machine (15) is used for the last rolling. The rolling of the fourth-level rolling machine (15) mainly performs final fine adjustment on the thickness, flatness and coating quality of the stainless steel mesh. (2) If the tertiary rolling process is cancelled, it is directly transported to the subsequent flying shear machine (16) through the belt conveyor (14) for flying shear operation.

3. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, The drying treatment steps of the first-level drying furnace (7) are as follows: (1) First, pre-dry in a low-temperature environment of 50-60 °C for 1-2 hours to initially remove most of the moisture in the catalyst coating. (2) Then raise the temperature to 100-120 °C and continue drying for 3-4 hours until the water content on the surface of the stainless steel mesh is lower than 1wt%.

4. According to the production process of an SCR plate type denitration catalyst described in claim 1, characterized in that The tension control range of the primary tension rectifier (4) is 500 - 800 N; The tension control of the secondary tension rectifier (8) is 400 - 600 N; The tension control of the tertiary tension rectifier (12) is 300 - 500 N; In addition, the rectification accuracy of the primary tension rectifier (4), secondary tension rectifier (8) and tertiary tension rectifier (12) is maintained at ±1 mm.

5. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that The roll pressing pressure of the primary roll press (5) is stably controlled at 5 - 10 MPa; The roll pressing pressure of the secondary roll press (9) is stably controlled at 6 - 12 MPa; The roll pressing pressure of the tertiary roll press (13) is stably controlled at 8 - 15 MPa; The roll pressing pressure of the quaternary roll press (15) is stably controlled at 10 - 20 MPa; In addition, the roll pressing speeds of the primary roll press (5), secondary roll press (9), tertiary roll press (13) and quaternary roll press (15) are all maintained at 5 - 8 m / min.

6. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, The drying conditions of the secondary drying furnace (10) are: drying in the temperature range of 120 - 150 °C, and the drying time is 2 - 3 hours.

7. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, The frequency of the flying shear (16) is 5 - 10 times / min, and the dimensional accuracy of the cut stainless steel mesh plate is controlled within ±2 mm.

8. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, The stamping pressure of the crank press (17) is 50 - 100 MPa, and the stamping speed is 3 - 5 times / min.

9. The production process of an SCR plate-type denitration catalyst according to claim 1, characterized in that, The straight-head welding machine (2) in the first step includes a straightening machine and a resistance welding machine, specifically: (1) Straighten the head of the unfolded stainless steel mesh plate with a straightening machine; (2) For the stainless steel mesh plate that needs to be spliced later, perform welding operations with a resistance welding machine.

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