A method for lining bricks of an autoclave

Abstract

The invention discloses a pressure autoclave lining brick method. The inner lining of the pressure autoclave treated by the method comprises, from outside to inside, a lead lining layer, an isolation film layer, a first 54 mm ceramic brick layer, a second 54 mm ceramic brick layer and a third 114 mm ceramic brick layer. The first 54 mm ceramic brick layer and the second 54 mm ceramic brick layer are built by RG series epoxy resin mortar, and the third 114 mm ceramic brick layer is built by water glass mortar, so that the advantages of high bonding strength of the RG series epoxy resin mortar and high temperature resistance of the water glass mortar are fully utilized. At the same time, the method adopts a lining structure of a Teflon-lined alloy sleeve for a weak pipe part of the pressure autoclave lining, so that the structural strength is enhanced and the overall service life of the pressure autoclave lining structure is improved. The pressure autoclave treated by the above-mentioned lining brick method has an operating temperature of 145-200° C. and an operating autoclave pressure of 0.55-1.4 MPa, and can process sulfate slurry materials with pH 0.5-2.5, so as to meet the production needs of nickel-cobalt oxygen pressure leaching.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrometallurgy equipment, and relates to an autoclave for pressure leaching nickel concentrate, nickel-cobalt sulfide, cobalt-rich matte and other slurries to produce nickel-cobalt sulfate solution and tailings, and specifically relates to a method for lining bricks of an autoclave. Background Art

[0002] At present, the nickel and cobalt metal pressure leaching production processes generally adopt two types of autoclaves: autoclaves with carbon steel inner lining titanium and autoclaves with carbon steel inner lining bricks, which are key equipment for the process production. The steel-titanium composite plate autoclave has a safety risk of spontaneous combustion under high oxygen partial pressure conditions and has the disadvantage of weak adaptability to various nickel-cobalt complex raw materials. Therefore, the application of the carbon steel inner lining titanium autoclave is restricted to a certain extent. The technology of the carbon steel inner lining brick autoclave is mature. Compared with the steel-titanium composite plate autoclave, it has its own unique advantages: it can be used in the process reaction of strong corrosion and high oxygen content, and there is no combustion danger under high oxygen conditions like the steel-titanium autoclave; it has strong adaptability to various nickel-cobalt miscellaneous raw materials. However, the carbon steel inner lining brick autoclave has high requirements for the lining brick technology method. Otherwise, the inner lining bricks are easily damaged and fall off during the use of the autoclave. After the inner lining bricks fall off, timely maintenance is required. The maintenance difficulty inside the autoclave is large, the maintenance period is long, and the production disturbance is large, which restricts the improvement of the annual production operation efficiency of the autoclave. Currently, due to the reduction of the grade of mineral resources, the process parameters in production are becoming more and more stringent, and the operating temperature and pressure of the nickel and cobalt pressure leaching autoclave increase accordingly, which requires higher lining brick technology methods for the autoclave. The present invention provides an advanced method for lining bricks of an autoclave, which ensures the long-term, high-efficiency and stable operation of the carbon steel inner lining brick type autoclave through means such as inspection of the lead layer of the lining brick base, design and processing of acid-resistant, temperature-resistant and pressure-resistant special-shaped brick plates, lining structure design, selection of mortar, and construction process control. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for lining bricks of an autoclave to solve the problems that the inner lining bricks are easily damaged and fall off during the use of the existing autoclave, the maintenance difficulty inside the autoclave is large, the maintenance period is long, and the production disturbance is large.

[0004] To achieve the above purpose, the present invention adopts the following technical solutions:

[0005] A method for lining bricks of an autoclave includes the following steps:

[0006] 1) Lead lining on the inner wall of the autoclave; apply a soldering flux on the surface of the inner wall of the autoclave, and then use the high-temperature melting force of the oxyacetylene flame to bond a lead lining layer on the surface of the inner wall of the autoclave;

[0007] The thickness of the lead lining layer is 6 mm; the specific construction method is as follows:

[0008] First, mechanically remove rust from the surface of the steel substrate, and then perform hydrochloric acid pickling;

[0009] Apply flux; the flux used is a zinc tin chloride solution (mass ratio of zinc chloride: tin chloride: water = 2:1:6).

[0010] Then, use the high-temperature melting force of the acetylene-oxygen flame to form a 6-mm-thick lead-tinned layer on the surface of the steel substrate, and make it in close contact with the steel shell. Then, brush the surface with clean water to remove the residual flux, and scrape the surface smooth;

[0011] The lead-tinned layer is firmly and densely bonded to the steel substrate, flat, and has a uniform thickness; there should be no inclusions, cracks, shrinkage cavities, etc. in the lead-tinned layer; to check the above phenomena and defects, the general method is to evenly apply 20% dilute sulfuric acid on the surface of the lead-tinned layer, and after standing for 24 hours, check for corrosion points (rust spots). If any, it indicates that there are the above defects at that place and need to be repaired until qualified.

[0012] For the tube sheet hole part, an alloy layer is prepared by arc spraying zinc-aluminum alloy or magnesium-aluminum alloy to replace the lead-tinned layer, and the thickness of the alloy layer is 4 - 6 mm.

[0013] 2) Construction of the isolation film; after the lead-tinned layer is inspected and accepted without error, first scrape and coat the diaphragm layer on the lower half of the kettle body in 3 times, with each scrape coating about 2 mm thick, and cure and solidify at 18 - 25°C for 24 hours at intervals after each scrape coating. The total thickness of the 3-time scrape coating of the isolation film is 6 mm. After the brickwork of the lower half of the kettle body is completed, then scrape and coat the diaphragm layer on the upper half of the kettle body.

[0014] The isolation film is coated with a phenolic epoxy vinyl resin-based paste anti-corrosion material; the component ratio in the phenolic epoxy vinyl resin-based paste anti-corrosion material is phenolic epoxy vinyl resin: curing agent: accelerator: acid-resistant powder = 100: 2 - 4: 0.5 - 4: 180 - 240, the acid-resistant powder is cast stone powder or barium sulfate powder, the curing agent is methyl ethyl ketone peroxide, and the accelerator is cobalt naphthenate or cobalt isooctanoate.

[0015] The construction of the diaphragm layer is carried out on the basis of the qualified inspection of the lead-tinned layer. The construction of the diaphragm layer starts from the lower half of the kettle body. After the brickwork of the lower half of the kettle body is completed, a construction platform is set up, and then the diaphragm layer on the upper half of the kettle body is constructed. After the diaphragm layer cement is stirred evenly, it is applied by scraping and smoothing. The total construction thickness is 6 mm thick and is carried out in 3 passes. Each time during construction, first step, layout and zoning: divide the area of one-time scraping film into grids with a size of 400 mm × 400 mm; second step, stick mold strips between the grids to leave a 10-mm-wide expansion joint. After the one-time scraping coating of the diaphragm layer sets and initializes for 1 - 2 hours, lift the mold strips; third step, after the one-time diaphragm layer is initially cured for 12 hours, scrape and level the 10-mm-wide expansion joint with the diaphragm material; fourth step, layout and zone in a staggered manner and repeat the previous three steps until the construction of the diaphragm layer is completed. Through the construction method of multiple and zone-by-zone thin scraping of the diaphragm layer in the present invention, the curing stress concentration of the diaphragm layer is solved, and the problem that the diaphragm layer may not be firmly bonded to the lead base layer and delaminate is avoided.

[0016] 3) Laying the first layer of ceramic bricks for the cylinder body: First, use the cross method to determine the center line of the kettle bottom. Then, use the round-bottom arc surface laying method to first lay and position the bricks around the pipe holes by trial laying, and then lay the bricks in other parts; for the laying of the first layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the bottom isolation film of the kettle, control the thickness of the mortar layer to be 4 - 6 mm, the brick joint to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm;

[0017] 4) Laying the second layer of ceramic bricks for the cylinder body: The laying process is the same as that of the first layer of ceramic bricks, ensuring that the second layer of ceramic bricks and the first layer of ceramic bricks are laid with double-layer staggered joints after laying to prevent "cross" through joints and "through" joints;

[0018] 5) Fabrication and installation of pipe hole sleeves: First, according to the sizes of the stirring holes, process pipeline holes, and instrument detection holes distributed on the autoclave cylinder body, fabricate corresponding alloy sleeves; secondly, immediately slip on a Teflon plastic sleeve after scraping 4 - 5 mm thick phenolic epoxy vinyl resin anticorrosive mortar on the outer wall of the alloy sleeve; then, scrape 4 - 5 mm thick phenolic epoxy vinyl resin anticorrosive mortar on the inner wall of the tube plate hole where the diaphragm layer construction has been completed and install the Teflon plastic sleeve to complete the fixation of the sleeve;

[0019] 6) Laying the head bricks: First, use the cross method to determine the center line of the head. Then, use the arc surface laying method to lay the bricks in the order of the first layer of ceramic bricks, the second layer of ceramic bricks, and then the third layer of ceramic bricks; for the first layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the head isolation film; for the second layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the first layer of ceramic bricks of the head; for the third layer of ceramic bricks, use sodium silicate mortar to paste 114 mm thick ceramic bricks on the second layer of ceramic bricks of the head; the three layers of ceramic bricks are laid with staggered joints with anticorrosive mortar to prevent "cross" through joints and "through" joints; for each layer of bricks, first determine the center brick of the head according to the center line of the head, and then start laying the other bricks of the head from the center brick of the head. The head bricks and the bricks of the kettle cylinder body are laid together at the joint; control the thickness of the mortar layer to be 4 - 6 mm, the brick joint to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm;

[0020] 7) Laying the third layer of ceramic bricks for the cylinder body: On the second layer of ceramic bricks of the cylinder body, determine the center line of the cylinder body by laying out lines according to the center line of the kettle bottom. Then, according to the center line of the cylinder body, starting from the bottom up, use sodium silicate mortar to lay and paste 114 mm thick ceramic bricks in the order of first laying the tube plate holes and then the cylinder body, control the thickness of the mortar layer to be 4 - 6 mm, the brick joint to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm;

[0021] 8) Partition wall brick masonry: On the third layer of ceramic bricks of the cylinder, determine the center line of the cylinder according to the center line of the bottom of the kettle, and then determine the center line of each partition wall according to the center line of the cylinder and the spacing of the partition wall. Use water glass mortar to masonry the ceramic bricks of the partition wall to the required height, control the thickness of the mortar layer to 4~6mm, the brick joint to 2~3mm, and the height difference between adjacent bricks ≤2mm;

[0022] 9) Curing and solidification of lining brick layer: After the lining brick construction in the above steps 1) to 8) is completed, the mortar needs to be maintained at a temperature of 20-30℃ for 7-15 days to allow the mortar to cure;

[0023] 10) Pickling of lining brick layer: After the mortar is solidified, pickle the mortar joints with 40% sulfuric acid solution, once every 24 hours, for a total of 4 times; because water glass mortar is an inorganic material, the reaction is not complete after on-site mixing and masonry, so pickling is required to promote its complete reaction and improve the corrosion resistance, bonding strength and other properties of the mortar;

[0024] 11) Pressure rise and fall heat treatment of lining brick layer: Add nickel sulfate solution into the kettle body after pickling. When the nickel sulfate solution reaches 75% of the kettle capacity, start stirring and increase the pressure and temperature evenly according to the temperature and pressure rise curve of the mastic. The temperature rise rate is 5~10℃ / h and the pressure rise rate is 0.1~0.2MPa / h to complete the heat treatment of the lining brick layer.

[0025] In summary, the operating temperature of the autoclave after the lining brick treatment of the present invention is 145-200°C, the operating pressure is 0.55~1.4MPa, and it can process pH 0.5~2.5 sulfate slurry materials. The production operating temperature and pressure of the autoclave are significantly higher than the operating temperature and pressure (145~170°C, 0.55~0.8Mpa) of the steel lining brick autoclave for treating sulfate slurry materials in the past, which meets the needs of the nickel and cobalt oxygen pressure leaching process, and is of great significance to ensure the long-term efficient and stable operation of the carbon steel lined brick autoclave. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an overall schematic diagram of the lining brick structure of the autoclave of the present invention;

[0027] Figure 2 It is a partial schematic diagram of the lining brick structure of the autoclave of the present invention;

[0028] Figure 3 This is a front view of the retaining wall of the present invention;

[0029] Figure 4 This is a plan view of the retaining wall structure of the present invention;

[0030] Figure 5 This is a schematic diagram of the pipe lining structure of the present invention;

[0031] Figure 6This is the heat treatment temperature and pressure curve graph of the lining brick structure of the present invention. Detailed implementation manners

[0032] The present invention will be further explained and described below in conjunction with the accompanying drawings and detailed implementation manners.

[0033] The structural dimensions of the autoclave are (Ø2800×9000mm).

[0034] As Figures 1-5 shown, the method for lining bricks of the autoclave of the present invention includes the following steps:

[0035] 1) Tinning the inner wall of the autoclave; applying a soldering flux on the surface of the inner wall of the autoclave, and then using the high-temperature melting force of the acetylene-oxygen flame to bond a tinned layer on the surface of the inner wall of the autoclave and make it in close contact with the steel shell;

[0036] The thickness of the tinned layer is 4 - 6mm, and the specific construction steps are as follows:

[0037] a. First, mechanically remove rust from the surface of the steel substrate, and then perform hydrochloric acid pickling;

[0038] b. Apply a soldering flux, and the soldering flux uses a zinc-tin chloride solution;

[0039] c. Then use the high-temperature melting force of the oxyacetylene flame to form a tinned bottom layer with a thickness of 2 - 3mm on the surface of the steel substrate, then brush the surface with clean water to remove the residual soldering flux, and scrape the surface smooth;

[0040] d. Then, using the same construction method as the tinned bottom layer, perform the construction of the tinned covering layer, and the thickness of a single-layer tinned covering layer is 2 - 3mm.

[0041] After the construction of the tinned layer is completed, inspection should be carried out to ensure that there are no inclusions, cracks, shrinkage holes, etc. on the surface of the tinned layer; the specific inspection method is: evenly apply 20% dilute sulfuric acid on the surface of the tinned layer, and after standing for 24 hours, check for corrosion points (rust spots). If there are any, it indicates that there are the above-mentioned defects at that place and need to be repaired until qualified.

[0042] For the tube plate hole part, an alloy layer is prepared by arc spraying zinc-aluminum alloy or magnesium-aluminum alloy to replace the tinned layer, and the thickness of the alloy layer is 4 - 6mm.

[0043] 2) Construction of the isolation film; after the inspection and acceptance of the tinned layer are correct, first scrape the isolation film on the lower half of the autoclave, scrape it in 3 times, with each scrape about 2mm thick, and cure it for 24 hours at 18 - 25°C after each scrape. The total thickness of the isolation film scraped in 3 times is 6mm; after the brickwork of the lower half of the autoclave is completed, then scrape the isolation film on the upper half of the autoclave;

[0044] The isolation film is coated with a phenolic epoxy vinyl resin-based paste anti-corrosion material; the component ratios in the phenolic epoxy vinyl resin-based paste anti-corrosion material are phenolic epoxy vinyl resin: curing agent: accelerator: acid-resistant powder = 100: 2-4: 0.5-4: 180-240. The acid-resistant powder is cast stone powder or barium sulfate powder, the curing agent is methyl ethyl ketone peroxide, and the accelerator is cobalt naphthenate or cobalt isooctanoate.

[0045] The specific construction method is as follows: Each time during construction, first step, layout and partition: Divide the area for one-time film scraping into grids with a size of 400mm×400mm; second step, stick mold strips between the grids leaving a 10mm-wide expansion joint. After the first-layer diaphragm is scraped and initially set after 1-2 hours, lift the mold strips; third step, after the first-layer diaphragm is initially cured for 12 hours, scrape and level the 10mm-wide expansion joint with the diaphragm material; fourth step, repeat the previous three steps with staggered layout and partition until the construction of the diaphragm layer is completed.

[0046] The construction method of scraping the diaphragm layer thinly in multiple times and partitions avoids the concentration of curing stress in the diaphragm layer and solves the problem that the diaphragm layer may not adhere firmly to the lead base layer and delaminate.

[0047] 3) Laying the first layer of ceramic bricks on the cylinder body: First, use the cross method to determine the center line of the kettle bottom, and then use the round-bottom arc surface laying method to lay the bricks around the pipe holes by first trial-laying and positioning, and then laying other parts; for the laying of the first layer of ceramic bricks, use a phenolic epoxy vinyl resin anti-corrosion mortar (RG series) to paste 54mm-thick ceramic bricks on the isolation film at the kettle bottom, control the thickness of the mortar layer to be 4-6mm, the brick joint to be 2-3mm, and the height difference between adjacent bricks to be ≤2mm;

[0048] 4) Laying the second layer of ceramic bricks on the cylinder body: The laying process is the same as that of the first layer of ceramic bricks to ensure that the second layer of ceramic bricks and the first layer of ceramic bricks are laid with double-layer staggered joints after laying, preventing "cross" through joints and "through" joints;

[0049] 5) Fabrication and installation of pipe hole sleeves: First, according to the sizes of the stirring holes, process pipeline holes, and instrument detection holes distributed on the pressure kettle cylinder body, fabricate corresponding alloy sleeves; second, scrape 4-5mm-thick phenolic epoxy vinyl resin anti-corrosion mortar on the outer wall of the alloy sleeve and immediately put on a Teflon plastic sleeve; then, scrape 4-5mm-thick phenolic epoxy vinyl resin anti-corrosion mortar on the inner wall of the pipe plate hole where the diaphragm layer construction has been completed and install the Teflon plastic sleeve to complete the sleeve fixation; subsequently, supplement the laying of the first layer and the second layer of ceramic bricks around the pipe plate hole to make the sleeve closely combined and fixed with the ceramic brick layer;

[0050] 6) Laying the head bricks: First, use the cross method to determine the center line of the head, and then use the arc surface laying method to lay the bricks in the order of the first layer of ceramic bricks, the second layer of ceramic bricks, and then the third layer of ceramic bricks (the brick laying rules are as Figure 1As shown in the figure); for the first layer of ceramic bricks, phenolic epoxy vinyl ester resin anticorrosive mortar is used to paste 54-mm-thick ceramic bricks on the head isolation film; for the second layer of ceramic bricks, phenolic epoxy vinyl ester resin anticorrosive mortar is used to paste 54-mm-thick ceramic bricks on the first layer of ceramic bricks on the head; for the third layer of ceramic bricks, sodium silicate mortar is used to paste 114-mm-thick ceramic bricks on the second layer of ceramic bricks on the head; the three layers of ceramic bricks are laid with anticorrosive mortar in a staggered joint pattern to prevent "cross" through joints and "straight" joints; for each layer of bricks, first determine the center brick of the head according to the center line of the head, and then start laying other bricks of the head from the center brick of the head. The bricks of the head and the bricks of the kettle body are laid together at the joint; control the mortar layer thickness at 4-6 mm, the brick joint at 2-3 mm, and the height difference between adjacent bricks ≤ 2 mm;

[0051] 7) Laying the third layer of ceramic bricks on the cylinder: On the second layer of ceramic bricks on the cylinder, determine the center line of the cylinder according to the center line of the kettle bottom by laying out the line, and then according to the center line of the cylinder body, follow the principle of laying the tube plate holes first and then the cylinder body, and lay and paste 114-mm-thick ceramic bricks from bottom to top using sodium silicate mortar, controlling the mortar layer thickness at 4-6 mm, the brick joint at 2-3 mm, and the height difference between adjacent bricks ≤ 2 mm; the sodium silicate mortar is Asplit® HB mortar;

[0052] 8) Laying the partition wall bricks: On the third layer of ceramic bricks on the cylinder, determine the center line of the cylinder according to the center line of the kettle bottom by laying out the line, and then determine the center line for laying each partition wall according to the center line of the cylinder body and the partition wall spacing. Use sodium silicate mortar to lay the partition wall ceramic bricks to the required height, controlling the mortar layer thickness at 4-6 mm, the brick joint at 2-3 mm, and the height difference between adjacent bricks ≤ 2 mm; here, the partition wall spacing and height are determined according to the structural dimensions and process of the autoclave used on site, and it is not restricted here as long as it does not affect the normal operation of the autoclave;

[0053] 9) Curing and solidifying the lining brick layer: After the lining brick construction in the above steps 1) to 8) is completed, the mortar needs to be maintained in an environment with a temperature of 20-30 °C for 7-15 days to enable the mortar to complete solidification;

[0054] 10) Pickling the lining brick layer; after the mortar is solidified, pickle the mortar joints with a 40% sulfuric acid solution, treat it once every 24 hours, and treat it a total of 4 times;

[0055] 11) Heat treatment of the lining brick layer for pressure increase and decrease: In order to make the lining brick layer of the autoclave adapt to the temperature and pressure technical parameter conditions of the production process, the above lining brick layer needs to be heat-treated:

[0056] Add nickel sulfate solution to the pickled kettle body. When the nickel sulfate solution reaches 75% of the kettle body capacity, start stirring and uniformly increase the pressure and temperature according to the pressure increase and temperature increase curve of the mortar (as Figure 6 shown), with a temperature increase rate of 5-10 °C / h and a pressure increase rate of 0.1-0.2 MPa / h;

[0057] Precautions during the solution heat treatment:

[0058] a. Pass in steam to heat up. When the temperature rises to 60 °C, keep it warm for 4 hours, and then continue to heat up to 80 °C and keep it warm for 8 hours;

[0059] b. Continue to heat up to 120 °C, and at the same time start to pass in nitrogen to slowly heat up and increase the pressure. The pressure control speed is 0.1 MPa - 0.2 MPa / h;

[0060] c. When the temperature rises to 120 °C, control the pressure at 0.6 MPa and keep it warm for 4 hours;

[0061] d. Continue to pass in steam, heat up to 150 °C, control the pressure at 0.75 MPa, maintain this state and keep it warm for 14 h, and the pressure control speed is 0.1 - 0.2 MPa / h;

[0062] e. Continue to heat up to 180 °C and keep it warm and under pressure for 12 h, and control the pressure at 1.0 MPa;

[0063] f. After keeping it warm and under pressure at 180 °C for 12 hours, slowly cool down and reduce the pressure. The temperature control speed is 5 - 10 degrees / hour, and the pressure control speed is 0.1 - 0.2 MPa / h.

[0064] It is found through actual use that after the autoclave is treated by the above - mentioned lining brick method, the operating temperature of the autoclave is 145 - 200 °C, the operating autoclave pressure is 0.55 - 1.4 MPa, and it can treat sulfate pulp materials with pH 0.5 - 2.5. The production operating temperature and pressure of the autoclave are significantly higher than those of the previous steel - lined brick autoclave for treating sulfate pulp materials (145 - 170 °C, 0.55 - 0.8 Mpa).

[0065] For the rest of the un - described parts, refer to the description in GB 50726 - 2011 "Code for Construction of Anti - corrosion Engineering of Industrial Equipment and Pipelines".

Claims

1. A method for lining bricks of an autoclave, characterized in that, it includes the following steps: 1) Tinning the inner wall of the autoclave; applying a soldering flux on the surface of the inner wall of the autoclave, and then using the high-temperature melting force of an acetylene-oxygen flame to bond a tinned layer on the surface of the inner wall of the autoclave and make it in close contact with the steel shell; Using arc spraying zinc-aluminum alloy or magnesium-aluminum alloy to prepare an alloy layer at the tube sheet hole part of the autoclave to replace the tinned layer; 2) Construction of the isolation film; after the tinned layer is inspected and accepted without error, first scrape and coat the isolation film on the lower half of the autoclave, scrape and coat it in 3 times, with each time being 2 mm thick, and cure it for maintenance at 18 - 25 °C with an interval of 24 hours each time. The total thickness of the isolation film after 3 times of scraping and coating is 6 mm; after the brick laying of the lower half of the autoclave is completed, then scrape and coat the isolation film on the upper half of the autoclave; 3) Laying the first layer of ceramic bricks on the cylinder body: First, use the cross method to determine the center line of the bottom of the autoclave, and then use the round-bottom arc surface laying method to lay the bricks around the tube holes first by trial placement and positioning, and then lay the bricks in other parts; For the laying of the first layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the isolation film at the bottom of the autoclave, control the thickness of the mortar layer to be 4 - 6 mm, the brick joints to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm; 4) Laying the second layer of ceramic bricks on the cylinder body: The laying process is the same as that of the first layer of ceramic bricks, ensuring that the second layer of ceramic bricks and the first layer of ceramic bricks are laid with double-layer staggered joints after laying to prevent "cross" through joints and "straight" through joints; 5) Fabrication and installation of the tube hole sleeves: First, according to the sizes of the stirring holes, process pipeline holes, and instrument detection holes distributed on the autoclave cylinder body, fabricate the corresponding alloy sleeves; Secondly, scrape and coat 4 - 5 mm thick phenolic epoxy vinyl resin anticorrosive mortar on the outer wall of the alloy sleeve and immediately put on a Teflon plastic sleeve; Then, scrape and coat 4 - 5 mm thick phenolic epoxy vinyl resin anticorrosive mortar on the inner wall of the tube sheet hole where the diaphragm layer construction has been completed and install the Teflon plastic sleeve to complete the fixing of the sleeve; 6) Laying the bricks on the head: First, use the cross method to determine the center line of the head, and then use the arc surface laying method to lay the bricks in the order of the first layer of ceramic bricks, the second layer of ceramic bricks, and the third layer of ceramic bricks; For the first layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the isolation film of the head; For the second layer of ceramic bricks, use phenolic epoxy vinyl resin anticorrosive mortar to paste 54 mm thick ceramic bricks on the first layer of ceramic bricks of the head; For the third layer of ceramic bricks, use sodium silicate mortar to paste 114 mm thick ceramic bricks on the second layer of ceramic bricks of the head; The three layers of ceramic bricks are laid with staggered joints with the anticorrosive mortar to prevent "cross" through joints and "straight" through joints; For each layer of bricks, first determine the center brick of the head according to the center line of the head, and then start laying the other bricks of the head from the center brick of the head. The bricks of the head are laid together with the bricks of the autoclave cylinder body at the joint; Control the thickness of the mortar layer to be 4 - 6 mm, the brick joints to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm; 7) Laying the third layer of ceramic bricks on the cylinder body: On the second layer of ceramic bricks on the cylinder body, determine the center line of the cylinder body by laying out lines according to the center line of the bottom of the autoclave. Then, according to the center line of the cylinder body, lay and paste 114 mm thick ceramic bricks from bottom to top using sodium silicate mortar in the order of laying the tube sheet holes first and then the cylinder body, controlling the thickness of the mortar layer to be 4 - 6 mm, the brick joints to be 2 - 3 mm, and the height difference between adjacent bricks to be ≤ 2 mm; 8) Partition brick masonry: On the third layer of ceramic bricks in the cylinder, the center line of the cylinder is determined by laying out lines according to the center line of the kettle bottom. Then, according to the center line of the cylinder and the partition spacing, the center line of each partition masonry is determined. The partition ceramic bricks are masoned to the required height with sodium silicate mortar, controlling the mortar layer thickness at 4 - 6 mm, the brick joint at 2 - 3 mm, and the height difference between adjacent bricks ≤ 2 mm; 9) Curing of the lining brick layer: After the lining brick construction in the above steps 1) to 8) is completed, the mortar needs to be maintained for 7 - 15 days in an environment with a temperature of 20 - 30 °C to complete the curing of the mortar; 10) Acid pickling of the lining brick layer; After the mortar is cured, the mortar joints are pickled with a 40% sulfuric acid solution, treated once every 24 hours, and treated a total of 4 times; 11) Heat treatment of the lining brick layer for pressure increase and decrease: Nickel sulfate solution is added to the pickled kettle body. When the nickel sulfate solution reaches 75% of the kettle body capacity, start stirring and uniformly increase the pressure and temperature according to the heating and pressure increase curve of the mortar. The heating rate is 5 - 10 °C / h, and the pressure increase rate is 0.1 - 0.2 MPa / h to complete the heat treatment of the lining brick layer.

2. A method for lining bricks of a pressure kettle as described in claim 1, characterized in that: In step 1), the thickness of the lead lining layer is 4 - 6 mm, and the specific construction steps are as follows: a. First, mechanically remove rust from the surface of the steel matrix, and then perform hydrochloric acid pickling; b. Apply a soldering flux; c. Then, use the high-temperature melting force of an oxyacetylene flame to form a lead lining bottom layer with a thickness of 2 - 3 mm on the surface of the steel matrix. Then, brush the residual soldering flux on the surface with clean water and scrape the surface smooth; d. Then, use the same construction method as the lead lining bottom layer to construct the lead lining cover layer. The thickness of a single-layer lead lining cover layer is 2 - 3 mm.

3. A method for lining bricks of a pressure kettle as described in claim 1, characterized in that: In step 2), the isolation film is coated with a phenolic epoxy vinyl resin-based paste anti-corrosion material; the mass ratio of each component in the phenolic epoxy vinyl resin-based paste anti-corrosion material is phenolic epoxy vinyl resin: curing agent: accelerator: acid-resistant powder = 100: 2 - 4: 0.5 - 4: 180 - 240. The acid-resistant powder is cast stone powder or barium sulfate powder, the curing agent is methyl ethyl ketone peroxide, and the accelerator is cobalt naphthenate or cobalt isooctanoate.

4. A method for lining bricks of a pressure kettle as described in claim 1, characterized in that: In step 11), uniformly increasing the pressure and temperature according to the heating and pressure increase curve of the mortar specifically means: a. Pass steam to heat up to 60 °C and keep warm for 4 hours, then continue to heat up to 80 °C and keep warm for 8 hours; b. Continue to heat up to 120 °C, and at the same time start to pass nitrogen to slowly increase the pressure and temperature, and control the pressure increase speed at 0.1 MPa - 0.2 MPa / h; c. When the temperature rises to 120 °C, control the pressure at 0.6 MPa and keep warm for 4 hours; d. Continue to pass steam, heat up to 150 °C, control the pressure at 0.75 MPa, maintain this state and keep warm for 14 h, and control the pressure increase speed at 0.1 - 0.2 MPa / h; e. Continue to heat up to 180 °C and keep warm and pressurized for 12 h, and control the pressure at 1.0 MPa; f. After maintaining the temperature and pressure at 180 °C for 12 hours, slowly cool down and reduce the pressure. The temperature control rate is 5-10 °C / h, and the pressure control rate is 0.1-0.2 MPa / h.

5. An autoclave processed by the lining brick method described in claim 1, characterized in that: the operating temperature of the autoclave is 145-200 °C, the operating autoclave pressure is 0.55-1.4 MPa, and it processes sulfate pulp materials with a pH of 0.5-2.5.

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