Preparation method of clean energy bulk curing barn inorganic plasticized microporous thermal insulation enclosure

Abstract

The invention provides a clean energy bulk curing barn inorganic plasticizing micropore heat preservation enclosure preparation method, and belongs to the technical field of tobacco curing equipment. The method comprises the steps that firstly, optimal heat preservation plate thickness configuration is determined through a multi-target optimization model; mixing aluminum silicate fiber, wollastonite and light calcium carbonate, and adding oxidized cellulose to prepare slurry; adding organic silicon modified polyurethane emulsion as a plasticizer and a foaming agent to form a microporous precursor; pouring into a mold, drying, demolding, carrying out heat treatment, and carrying out thermal decomposition by using a foaming agent to form a microporous structure; the surface is coated with a nano silicon dioxide solution to form a fireproof and waterproof layer; after accurate cutting is conducted according to a design drawing, inorganic adhesives are adopted to be installed on all parts of the curing barn, and joints are treated through inorganic fireproof sealing strips; finally, airtightness and thermal bridge detection is conducted, the system integrity and the energy efficiency performance are ensured, and the technical problem that in the prior art, a bulk curing barn heat preservation enclosure structure is low in thermal efficiency is solved.

Description

Technical Field

[0001] The invention belongs to the technical field of flue-cured tobacco production, and in particular relates to a method for preparing an inorganic plasticized microporous thermal insulation enclosure for a clean, energy-intensive flue-curing barn. Background Art

[0002] As a crucial facility for agricultural product processing, energy consumption in concentrated drying rooms accounts for a significant portion of production costs. Traditional concentrated drying rooms utilize brick-concrete structures or simple insulation materials such as polystyrene foam boards and glass wool as their enclosures. In practice, ordinary cement mortar is often used for bonding and fixing, supplemented by mechanical anchoring. This structural design and construction process are simple, resulting in relatively low construction costs, making it widely used in agricultural processing.

[0003] However, traditional baking barn insulation systems have significant drawbacks. First, conventional insulation materials have high thermal conductivity and insufficient thermal resistance, resulting in significant heat loss and low energy efficiency. Second, organic insulation materials are prone to aging and deformation, have poor combustion performance, and pose safety risks. Third, the insulation layer is not firmly bonded to the base layer, prone to hollowing and falling off, and improperly treated joints can cause severe thermal bridging. Finally, traditional insulation materials have poor adaptability to humid environments and temperature fluctuations, resulting in a short service life and high maintenance costs. In other words, the existing technology suffers from the low thermal efficiency of dense baking bar insulation enclosures. Summary of the Invention

[0004] In view of this, the present invention provides a method for preparing an inorganic plasticized microporous thermal insulation enclosure for a clean energy-intensive baking room, which can solve the technical problem of low thermal efficiency of the thermal insulation enclosure structure of a dense baking room in the prior art.

[0005] The present invention is achieved as follows: The present invention provides a method for preparing inorganic plasticized microporous thermal insulation enclosures for a clean, energy-intensive baking room, including: constructing a multi-objective optimization model to determine the thickness of the insulation board; preparing a slurry formed by mixing aluminum silicate fiber, wollastonite, and light calcium carbonate; adding organic silicon modified polyurethane emulsion as a plasticizer and foaming agent to form a microporous precursor; drying the microporous precursor in a mold and then demolding and heat treating the mold to allow the foaming agent to generate nitrogen through a thermal decomposition reaction to form a uniform microporous structure, while triggering an interfacial cross-linking reaction between microcrystalline cellulose and the inorganic matrix; coating the surface of the insulation board with a nano-silica solution to form a fireproof and water-resistant protective layer; cutting and installing the insulation board, and treating the joints with inorganic fireproof sealing strips.

[0006] Among them, the step of constructing a multi-objective optimization model to determine the thickness of the insulation board is specifically to construct a multi-objective optimization model based on the thermal balance calculation results of the dense baking room, with maximizing thermal resistance and minimizing construction costs as objective functions, and with structural stability, space limitations, and safety performance as constraints, and apply the Pareto optimization algorithm to solve it.

[0007] Among them, the thickness of the insulation board includes the thickness of the wall insulation board, the thickness of the roof insulation board, and the thickness of the ground insulation board. The optimal values are 60-80 mm, 80-100 mm, and 40-60 mm, respectively, meeting the thermal resistance value of not less than 2.0 square meters·degrees Celsius / watt.

[0008] The step of preparing the slurry is to mix aluminum silicate fiber, wollastonite and light calcium carbonate in a mass ratio of 70:20:10, add 5% oxidized cellulose by mass, add pure water in a solid-liquid ratio of 1:5, and stir at high speed for 10 to 15 minutes to prepare a uniform slurry.

[0009] The step of forming the microporous precursor is to add 3% by mass of silicone modified polyurethane emulsion as a plasticizer to the slurry, stir for 5 to 8 minutes, add 2% by mass of foaming agent, and continue stirring for 3 to 5 minutes to form the microporous precursor.

[0010] The drying step specifically involves pouring the microporous precursor into a pre-designed size mold, coating the inner wall of the mold with a release agent, and drying it at a temperature of 40 to 50 degrees Celsius for 12 to 24 hours to reduce the moisture content to below 10%.

[0011] Among them, the heat treatment step is specifically to demold the dried semi-finished product and place it in an oven at a temperature of 80 to 90 degrees Celsius for heat treatment for 4 to 6 hours, so that the foaming agent produces nitrogen through thermal decomposition reaction to form a uniform microporous structure, and at the same time trigger the interface cross-linking reaction between microcrystalline cellulose and inorganic matrix to enhance the structural stability of the material.

[0012] Among them, the step of forming the fireproof and water-resistant protective layer is specifically to coat the surface of the insulation board with a nano-silicon dioxide solution with a mass fraction of 15% and a thickness of 1 to 2 mm after heat treatment, and dry it at a temperature of 25 to 30 degrees Celsius for 8 to 12 hours.

[0013] The microporous precursor refers to a mixture containing an unreacted foaming agent, which forms a closed bubble structure with a diameter of 2 to 10 microns after subsequent heat treatment.

[0014] The silicone-modified polyurethane emulsion refers to a polymer emulsion prepared by copolymerization of silicone and polyurethane, which has hydrophobicity and flexibility, and can make the insulation board both waterproof and shock-resistant.

[0015] The present invention determines the optimal insulation board thickness through multi-objective optimization design, uses inorganic materials such as aluminum silicate fiber, wollastonite and light calcium carbonate as the main body, combines silicone-modified polyurethane emulsion as a plasticizer, introduces microcrystalline cellulose to enhance interface bonding, and ultimately forms a high-performance insulation material with a uniform microporous structure. This method solves the key defects of traditional baking room insulation systems. First, based on heat balance calculations and Pareto optimization algorithms, the optimal insulation layer thickness configuration that meets the thermal resistance value of not less than 2.0 square meters and degrees Celsius per watt is determined; second, through the composite of inorganic main materials and organic plasticizing modifiers, the unity of high strength and good flexibility of the material is achieved; third, the use of nano-silica surface protection layer and inorganic fireproof sealing strips to treat the joints effectively eliminates the thermal bridge effect and improves the overall airtightness and fire safety of the system; finally, the overall process design is simple and controllable, suitable for large-scale production applications. Through the organic combination of material formula design, structural optimization and process control, the technical problem of low thermal efficiency of the insulation enclosure structure of dense baking rooms has been successfully solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0018] like Figure 1 FIG. 1 is a flow chart of a method for preparing an inorganic plasticized microporous thermal insulation enclosure for a clean energy-intensive baking room provided by the present invention. The method comprises the following steps:

[0019] S01. Based on the heat balance calculation results of the intensive baking room, a multi-objective optimization model was constructed to determine the thickness of the wall insulation board, the roof insulation board, and the floor insulation board. The multi-objective optimization model used maximizing thermal resistance and minimizing construction costs as objective functions, and structural stability, space limitations, and safety performance as constraints. The Pareto optimization algorithm was applied to solve the problem, and the optimal values of the wall insulation board thickness, roof insulation board thickness, and floor insulation board thickness were determined to be 60-80 mm, 80-100 mm, and 40-60 mm, respectively, to ensure a thermal resistance of no less than 2.0 m2·°C / W.

[0020] S02. Aluminum silicate fiber, wollastonite, and light calcium carbonate were mixed in a mass ratio of 70:20:10, 5% by mass of oxidized cellulose was added, and pure water was added in a solid-liquid ratio of 1:5, and the mixture was stirred at high speed for 10 to 15 minutes to prepare a uniform slurry;

[0021] S03, adding 3% by mass of a silicone-modified polyurethane emulsion as a plasticizer to the slurry, stirring for 5 to 8 minutes, adding 2% by mass of a foaming agent, and continuing to stir for 3 to 5 minutes to form a microporous precursor;

[0022] S04, pouring the microporous precursor into a pre-designed size mold, coating the inner wall of the mold with a release agent, and drying at a temperature of 40 to 50 degrees Celsius for 12 to 24 hours to reduce the moisture content to below 10%;

[0023] S05. Demolding the dried semi-finished product and placing it in an oven at a temperature of 80 to 90 degrees Celsius for a heat treatment of 4 to 6 hours, so that the foaming agent generates nitrogen through thermal decomposition reaction to form a uniform microporous structure, and at the same time triggers the interfacial cross-linking reaction between the microcrystalline cellulose and the inorganic matrix, thereby enhancing the structural stability of the material. The microporous formation process follows the foam chemical kinetic equation;

[0024] S06. After the heat treatment, the surface of the insulation board is coated with a nano-silicon dioxide solution having a mass fraction of 15% to a thickness of 1 to 2 mm, and dried at a temperature of 25 to 30 degrees Celsius for 8 to 12 hours to form a fireproof and water-resistant protective layer;

[0025] S07. Cut the finished insulation boards according to the baking room design drawings, control the dimensional accuracy within the range of plus or minus 3 mm, and make the cut surface smooth without obvious defects;

[0026] S08. Use inorganic adhesive to install the insulation board on the wall, roof and floor of the baking room. Use inorganic fireproof sealing strips with a width of 80 to 100 mm at the joints to ensure that the thermal bridge effect coefficient of the joints is less than 0.05 W / m·°C.

[0027] S09. Optionally, it also includes an air tightness test after installation. Under the pressure difference of 50 Pa, the leakage rate does not exceed 0.5 cubic meters / hour and square meters. A comprehensive thermal imager test is also carried out to ensure that there are no significant thermal bridge points.

[0028] Among them, thermal resistance is a physical quantity that specifically characterizes the ability of insulation materials to prevent heat transfer. The value is equal to the material thickness divided by the thermal conductivity coefficient, and the unit is square meter·degrees Celsius / watt.

[0029] Among them, wollastonite is specifically an ultrafine mineral powder containing highly active silica components, with a particle size of 1 to 5 microns and a specific surface area greater than 15,000 square meters / kilogram. It is used to improve the strength and fire resistance of insulation boards.

[0030] Among them, silicone-modified polyurethane emulsion is a polymer emulsion prepared by copolymerization of silicone and polyurethane. It has hydrophobicity and flexibility, which can make the insulation board both waterproof and shock-resistant.

[0031] The microporous precursor specifically refers to a mixture containing an unreacted foaming agent, which forms a closed bubble structure with a diameter of 2 to 10 microns after subsequent heat treatment.

[0032] Among them, the thermal bridge effect coefficient specifically refers to the phenomenon of increased local thermal conductivity caused by material discontinuity or structural nodes in the insulation structure. The lower the value, the better the insulation performance.

[0033] Among them, the joint thermal bridge effect coefficient specifically refers to the local heat loss coefficient caused by structural discontinuity at the connection of the insulation board. Its value is affected by the joint width and the thermal conductivity of the filling material.

[0034] Among them, the air leakage rate specifically refers to the air permeability of the enclosing structure per unit area under a certain pressure difference condition per unit time, which is a key parameter for measuring the airtight performance of the baking room.

[0035] Among them, oxidized cellulose specifically refers to a polysaccharide derivative obtained by selective oxidation treatment of cellulose, with a molecular weight of 10,000 to 50,000 Daltons and a viscosity of 300 to 800 mPa·s, and is used as a thickener and binder for thermal insulation materials.

[0036] Among them, microcrystalline cellulose specifically refers to a high-crystallinity fine powder obtained by partial hydrolysis of plant cellulose. The fiber length is 20 to 50 microns and the crystallinity is greater than 80%. It is used to enhance the mechanical properties and dimensional stability of insulation boards.

[0037] Among them, nano-silica specifically refers to ultrafine silica particles with a particle size of 10 to 50 nanometers, a specific surface area of 150 to 300 square meters per gram, and a purity greater than 99.5%, which is used to enhance the surface hardness and wear resistance of insulation boards.

[0038] Among them, the multi-objective optimization model specifically refers to a mathematical model that simultaneously considers the two conflicting objectives of maximizing thermal resistance and minimizing construction costs, and obtains the optimal solution set through trade-offs. The model includes objective function 1 related to heat conduction, objective function 2 related to economic cost, as well as material mechanical property constraints, baking room space limitation constraints and fire safety constraints; objective function 1 is derived from the negative thermal resistance value calculated by the law of heat conduction, and the input variables are the thickness of the wall insulation board, the thickness of the top plate insulation board, the thickness of the ground insulation board and the thermal conductivity of the corresponding materials; objective function 2 is derived from the economic cost accounting formula, and the input variables are the thickness of the wall insulation board, the thickness of the top plate insulation board, the thickness of the ground insulation board, the unit volume cost and the surface area of each part of the baking room; the material mechanical property constraints are derived from structural mechanics calculations, limiting the insulation board thickness range to meet the structural stability requirements; the baking room space limitation constraints are derived from design specifications, limiting the total insulation board thickness to no more than the reserved installation space; the fire safety constraints are derived from fire protection requirements, limiting the overall combustion performance level of the insulation material combination to no less than Class A.

[0039] Among them, the foam chemical kinetics equation specifically refers to the mathematical expression that describes the bubble generation, growth and stabilization process during the micropore formation process. The input parameters include the decomposition rate constant of the foaming agent, reaction temperature, material viscosity, surface tension and solid content. These parameters are obtained through thermal analysis experiments, rheological tests and interface science measurements respectively; the output parameters are the micropore size distribution function and total porosity, which directly determine the thermal conductivity and mechanical properties of the insulation material.

[0040] Among them, the Pareto optimization algorithm specifically refers to a computational method for dealing with multi-objective optimization problems. It forms a Pareto front by finding a set of non-dominated solutions, and selects the optimal solution that meets the decision maker's preferences from it. The algorithm input comes from thermal performance test data and cost accounting data, and the algorithm output is the optimal wall insulation board thickness, the optimal roof insulation board thickness and the optimal ground insulation board thickness.

[0041] The specific implementation of the above steps is described in detail below.

[0042] The specific implementation of step S01 involves first collecting data on the design parameters and environmental conditions of the dense baking barn, including basic information such as the indoor-outdoor temperature difference range of 10-40 degrees Celsius, baking barn dimensions, the basic thermal conductivity of the wall materials, and the design service life. A heat conduction model is then constructed, using Fourier's law of heat conduction to calculate the thermal resistance of insulation materials of varying thicknesses. An economic analysis is then conducted to estimate the initial investment cost and long-term energy-saving benefits of insulation materials of varying thicknesses. A multi-objective optimization model is then established, maximizing thermal resistance and minimizing construction costs as the two objective functions, while also considering material mechanical property constraints, baking barn space constraints, and fire safety constraints. In this multi-objective optimization model, the material mechanical property constraint requires the wall insulation board thickness to be no less than 40 mm to ensure structural stability; the baking barn space constraint requires the wall insulation board thickness to be no more than 120 mm to meet design space requirements; and the fire safety constraint requires the overall combustion performance rating of the insulation material combination to be no less than Class A. A Pareto optimization algorithm is then applied to solve this multi-objective optimization problem, generating a Pareto frontier curve to identify the solution with the best overall performance. The optimal thicknesses for the wall insulation board, roof insulation board, and floor insulation board were ultimately determined to be 60-80 mm, 80-100 mm, and 40-60 mm, respectively, meeting the design requirement of a thermal resistance of at least 2.0 m2 / °C / W. The core purpose of this step was to determine the optimal insulation thickness configuration through scientific calculations, balancing insulation effectiveness and economic cost, and providing clear parameters for subsequent material preparation.

[0043] The specific implementation method of step S02 is to pre-treat the aluminum silicate fiber, dry it at 105 degrees Celsius for 2 to 4 hours to remove adsorbed moisture, and sieve it through a 40-mesh sieve to ensure uniform particles. Then, 70 parts by mass of the dried aluminum silicate fiber, 20 parts by mass of wollastonite, and 10 parts by mass of light calcium carbonate are weighed and placed in a high-speed mixer for dry mixing. The speed is set to 800 to 1000 rpm and the mixing time is 5 to 8 minutes to ensure that the three powders are fully mixed. Afterwards, an oxidized cellulose solution is prepared, 5 parts by mass of oxidized cellulose is taken, and 45 parts by mass of pure water at a temperature of 60 to 70 degrees Celsius is slowly added, and a low-speed stirrer with a speed of 300 to 400 rpm is used to stir for 15 to 20 minutes until it is completely dissolved to form a transparent viscous solution. The prepared oxidized cellulose solution is gradually added to the dry-mixed powder at a solid-to-liquid ratio of 1:5. Simultaneously, a high-speed mixer is activated at a speed of 1200-1500 rpm for 10-15 minutes, until a uniform slurry with good fluidity and no apparent agglomeration is formed. This step fully utilizes the bonding properties of oxidized cellulose and the thermal insulation properties of aluminum silicate fibers. High-speed dispersion technology is used to achieve uniform distribution of the components, laying the foundation for the subsequent formation of a microporous structure. The uniformity of the slurry significantly affects the thermal conductivity of the final insulation board. Insufficient mixing, resulting in uneven material, can increase the thermal conductivity by 15-25%.

[0044] The specific implementation method of step S03 is to first prepare a silicone-modified polyurethane emulsion, ensuring that its solid content is 40-50%, its pH value is 7.0-8.0, and its viscosity is 500-1000 mPa·s. Then, 3 parts by mass of the silicone-modified polyurethane emulsion is diluted with pure water in a ratio of 1:3 to form a dilution with a mass fraction of 10%. The diluted silicone-modified polyurethane emulsion is then slowly added to the slurry prepared in step S02, controlling the addition rate to 50-80 ml per minute, while maintaining the stirrer speed at 800-1000 rpm and the stirring time for 5-8 minutes. During the stirring process, the viscosity of the slurry is monitored to ensure that the viscosity is within the range of 1500-2500 mPa·s. Subsequently, 2 parts by mass of a foaming agent are weighed, which is azodicarbonamide with a particle size of 10-30 microns and a purity greater than 99%. Sprinkle the foaming agent evenly onto the surface of the slurry, quickly turn on the high-speed stirrer, increase the speed to 1500-1800 rpm, and stir for 3-5 minutes until the foaming agent is completely dispersed, no visible particles are left, and a uniform microporous precursor is formed. This step enhances the flexibility and hydrophobicity of the material by adding silicone-modified polyurethane emulsion as a plasticizer, while introducing the foaming agent to prepare for the subsequent formation of the microporous structure. The amount of plasticizer added is controlled at around 3%. Too low will increase the brittleness of the finished product, while too high will reduce the thermal insulation performance. The optimal addition amount is determined by rheological testing.

[0045] The specific implementation method of step S04 is to prepare the mold first, and select a stainless steel or aluminum alloy mold with a smooth inner wall. The mold size is determined according to the design requirements of the final product. Generally, the aspect ratio is controlled between 1.2 and 1.5, and the thickness is consistent with the optimization result of step S01. Then a layer of release agent is evenly coated on the inner wall of the mold. The release agent is a silicone oil-based substance, and the coating thickness is controlled at 0.1 to 0.2 mm. Then, the microporous precursor prepared in step S03 is fully stirred for 30 to 60 seconds to ensure uniformity, and then poured into the mold in a continuous and slow manner, taking care to avoid the introduction of bubbles, and the pouring height does not exceed 5 cm. Use a vibration platform to vibrate the mold injected with the microporous precursor, with a vibration frequency of 50 to 60 Hz and a vibration time of 30 to 60 seconds. The purpose is to eliminate possible large bubbles and spread the slurry evenly. The poured mold is transferred to a drying chamber at 40-50°C and 60-70% relative humidity for 12-24 hours of constant temperature drying. The sample surface is regularly inspected until the surface solidifies and the moisture content drops below 10%. This process utilizes a slow drying principle to avoid cracking and warping caused by excessive drying. The drying temperature should not exceed 50°C, as this will cause premature decomposition of the foaming agent and affect the subsequent formation of the microporous structure.

[0046] The specific implementation method of step S05 is to first let the dried semi-finished product stand at room temperature for 1 to 2 hours to uniformize the temperature and prevent deformation caused by thermal stress. Then carefully remove the semi-finished product from the mold, and avoid applying excessive pressure during the operation to prevent damage to the internal structure. The surface of the semi-finished product taken out should be flat, with no obvious defects on the edges. If there are small defects, they can be slightly trimmed with sandpaper. After that, 5 to 10 parts by mass of microcrystalline cellulose with a fiber length of 20 to 50 microns are placed in a drying oven. After mixing evenly, the semi-finished product is placed in an oven at a temperature of 80 to 90 degrees Celsius for heat treatment, and the heating rate is controlled at 10 to 15 degrees Celsius per hour to avoid cracking caused by sudden temperature changes. Maintain constant temperature heat treatment for 4 to 6 hours. At this stage, the foaming agent decomposes to produce nitrogen, forming a uniformly distributed microporous structure. At the same time, the microcrystalline cellulose undergoes an interfacial cross-linking reaction with the inorganic matrix, significantly enhancing the stability of the material structure. The formation of micropores during the heat treatment process follows the principles of foam chemical kinetics. Bubble generation, growth, and stabilization depend on parameters such as the decomposition rate of the foaming agent, material viscosity, and surface tension, ultimately forming a closed bubble structure with a diameter of 2 to 10 microns. The uniformity of bubble distribution directly affects the thermal insulation performance. After the heat treatment is completed, it is naturally cooled to room temperature at a rate no faster than 20 degrees Celsius per hour to avoid the formation of microcracks caused by thermal stress. Temperature control in this process is crucial. Too low a temperature will lead to insufficient foaming, while too high a temperature will cause the bubbles to over-expand or even rupture. The optimal temperature range is determined by differential scanning calorimetry.

[0047] The specific implementation method of step S06 is to first prepare a nano-silicon dioxide solution, take 15 parts by mass of nano-silicon dioxide, with a particle size of 10 to 50 nanometers, a specific surface area of 150 to 300 square meters per gram, and a purity greater than 99.5%, disperse it in 85 parts by mass of pure water, add 0.5 to 1.0 parts by mass of a dispersant, and use ultrasonic dispersion technology for treatment, with an ultrasonic power of 300 to 500 watts and a treatment time of 15 to 30 minutes until a stably dispersed solution is formed. Then, a high-pressure airless spraying device is used to coat the surface of the heat-treated insulation board, with the spraying pressure controlled at 0.8 to 1.2 MPa, the distance between the nozzle and the insulation board surface being maintained at 15 to 25 cm, and the nozzle moving at a constant speed to ensure a uniform coating with a thickness controlled at 1 to 2 mm. After coating is completed, the insulation board is placed in an environment with a temperature of 25 to 30 degrees Celsius and a relative humidity of 50 to 60% to dry for 8 to 12 hours, during which dust contamination and mechanical vibration are avoided. During the drying process, the nanosilica particles form a dense network structure, forming a strong bond with the insulation board substrate, ultimately forming a protective layer that is both fireproof and water-resistant. This coating effectively increases the surface hardness of the insulation board to Mohs hardness levels 5-6, while also providing excellent water resistance with a water contact angle greater than 120 degrees, significantly extending the service life of the insulation board in high-humidity environments. The concentration of the nanosilica solution is a critical parameter: too low a concentration will result in insufficient protection, while too high a concentration will cause the coating to crack. The optimal concentration range was determined through orthogonal experimental methods.

[0048] The specific implementation of step S07 involves first determining the precise dimensional requirements for the insulation panels based on the barn design drawings, including standard panel sizes and non-standard sizes for specific locations. Appropriate cutting equipment is then selected, typically a diamond wire saw or a high-pressure water jet cutter. The former is suitable for straight-line cutting with an accuracy of ±1 mm, while the latter is suitable for cutting curves or special shapes with an accuracy of ±2 mm. A cutting plan is developed, adhering to the principle of maximizing material utilization. A dynamic programming algorithm is used to calculate the optimal cutting path to minimize waste. The panels are cut according to the cutting plan, with a cutting speed of 50-80 mm / min to prevent edge chipping caused by excessive cutting speed or overheating and damage to the microporous structure caused by excessive cutting speed. After cutting, the cut surfaces are gently polished with fine-grit sandpaper (320-400 grit) to remove burrs and minor defects, ensuring a flatness tolerance of no more than 0.5 mm / m. The cut panels are then dimensional inspected, with a sampling rate of at least 10%, to ensure dimensional accuracy within ±3 mm. The purpose of this step is to accurately process the insulation board according to actual needs, providing materials with uniform specifications and precise dimensions for subsequent installation. The cutting accuracy has a significant impact on the final airtightness and thermal bridge effect.

[0049] The specific implementation method of step S08 is to first check the installation surface to ensure that the flatness error of the wall, top plate and ground surface does not exceed 5 mm / m, and clean the surface to remove impurities such as dust and oil stains that affect bonding. Then prepare the inorganic adhesive, select water glass inorganic glue, add 10 to 15 parts by mass of wollastonite as reinforcing filler, stir evenly to form a paste, and control the setting time to 30 to 40 minutes. Use a toothed scraper to evenly apply the inorganic adhesive on the installation surface, with a thickness of 3 to 5 mm and a tooth spacing of 8 to 10 mm to ensure that the coverage is not less than 80%. Install the cut insulation board to the surface coated with adhesive according to the designed position. During installation, the board should be lightly pressed and slightly moved to ensure full contact and bonding. Use a spirit level to check the horizontal and vertical degree of the installed board, with an allowable error of no more than 3 mm / m. The treatment of joints between panels is crucial. The joint width is controlled at 3 to 5 mm. First, fill the joint with a fireproof sealing strip, and then cover the joint surface with an inorganic fireproof sealing strip with a width of 80 to 100 mm to form a double-sealed structure. The inorganic fireproof sealing strip is made of an intumescent inorganic material with a fire resistance rating of no less than A1. It can expand and seal the gap under fire conditions. The thermal bridge effect at the joint is simulated and calculated using thermal bridge analysis software to ensure that the joint thermal bridge effect coefficient is less than 0.05 W / m·°C. Local reinforcement measures are added if necessary. This step significantly reduces the thermal bridge effect through sophisticated installation technology and joint treatment technology, improving overall thermal insulation performance and fire safety.

[0050] Step S09 is an optional step. Its specific implementation method is to first close all normal openings in the baking room, including doors, windows, vents, etc., so that the baking room is in a completely closed state. Then, install airtightness testing equipment, including a variable frequency fan, a differential pressure gauge, a flow meter, etc. The maximum air volume of the variable frequency fan is not less than 5000 cubic meters per hour, the accuracy of the differential pressure gauge is not less than 1 Pa, and the accuracy of the flow meter is not less than 0.1 cubic meters per hour. According to the airtightness testing principle of the wind pressure method, a pressure difference of 50 Pa is formed inside and outside the baking room. This pressure value simulates the actual use state under medium wind speed conditions. Keep the pressure stable for 15 to 20 minutes, record the amount of compensatory airflow required to maintain this pressure difference, and use an infrared thermal imager to scan the perimeter of the baking room to detect temperature anomalies. Calculate the air leakage rate, that is, the amount of air infiltration per unit area of the enclosure structure under a certain pressure difference, to ensure that it does not exceed the standard of 0.5 cubic meters per hour per square meter. This standard is determined with reference to the airtightness requirements of passive houses. Abnormal temperature spots detected by the infrared thermal imager are marked and repaired, typically with a high-elasticity sealant for local reinforcement. After repair, airtightness testing is repeated until the requirements are met. Airtightness testing is a key step in evaluating the overall performance of the insulation envelope. Through both airtightness testing and thermal bridge detection, we ensure that the resulting densely packed oven has excellent insulation and energy efficiency.

[0051] Specifically, the principle of the present invention is as follows: The technical solution of the present invention is based on the principles of multi-material composite and structural optimization. Through the cross-integration of materials science, thermal physics and chemical processes, it achieves high efficiency, energy saving and long-term stability of the thermal insulation enclosure structure of the dense baking room. Its working principle is mainly reflected in the following aspects:

[0052] First, in the design of the insulation structure, thermal balance calculations and multi-objective optimization theory were applied to establish a mathematical model for maximizing thermal resistance and minimizing construction costs. Using a Pareto optimization algorithm, the optimal thickness configuration for the wall, roof, and floor insulation layers was determined, while meeting structural stability, spatial limitations, and safety performance constraints. This scientifically calculated design approach overcomes the limitations of traditional empirical design and achieves an optimal balance between insulation effectiveness and cost-effectiveness.

[0053] Secondly, in terms of the material system, aluminum silicate fiber was selected as the primary material, owing to its low thermal conductivity and excellent high-temperature stability. Wollastonite provides a highly active silica component, enhancing the material's strength and fire resistance. Light calcium carbonate adjusts the material's density and heat capacity. Oxidized cellulose, used as a thickener and binder, enhances the connectivity and integrity of the material's internal structure. The introduction of a silicone-modified polyurethane emulsion as a plasticizer imparts excellent water resistance and seismic resistance, compensating for the brittleness and cracking of traditional inorganic insulation materials.

[0054] In terms of microstructural construction, the thermal decomposition reaction of the foaming agent is controlled to form a closed cell structure with a diameter of 2 to 10 microns. This microporous structure is based on the principles of foam chemical kinetics. By regulating parameters such as the foaming agent decomposition rate, reaction temperature, material viscosity, and surface tension, precise control of bubble size and distribution is achieved. The closed microporous structure significantly reduces the thermal conductivity of the material, blocking the path of heat transfer, while maintaining good mechanical properties.

[0055] In terms of joint treatment and system integration, inorganic fireproof sealant strips are used for joint treatment. Precise cutting techniques and inorganic adhesive installation ensure that the thermal bridge effect coefficient of the joints is less than 0.05 W / m·°C. The application of a nano-silica surface protective layer further enhances the surface hardness, wear resistance, and water resistance of the insulation board. Comprehensive airtightness testing and thermal imaging inspections ensure the integrity and effectiveness of the entire system.

[0056] In summary, the present invention successfully solves the technical problems of low thermal efficiency and poor durability of the insulation enclosure structure of the dense baking room, and realizes efficient energy saving and long-term stable operation of the clean energy dense baking room.

[0057] A specific embodiment 1 of the present invention is provided below. The specific implementation of each step in this embodiment 1 is described in detail as follows.

[0058] The specific implementation of step S01 is to first collect data on the design parameters and environmental conditions of the dense baking room, including basic information such as the indoor and outdoor temperature difference range of 10 to 40 degrees Celsius, the baking room dimensions, the basic thermal conductivity of the wall material, and the design service life. Then, a heat conduction model is constructed to calculate the thermal resistance of insulation materials of different thicknesses based on Fourier's law of heat conduction. Subsequently, a multi-objective optimization model is established, with maximizing thermal resistance and minimizing construction costs as the two objective functions, while considering the constraints of material mechanical properties, baking room space limitations, and fire safety constraints. The multi-objective optimization problem is specifically expressed as follows:

[0059]

[0060] Where, Indicates the negative value of thermal resistance, f2(d w , d r , d f )=c w ·d w ·A w +c r ·d r ·A r +c f ·d f ·A f represents the total cost, d w is the thickness of the wall insulation board, ranging from 40 to 120 mm, d r is the thickness of the top insulation board, ranging from 60 to 140 mm, d f is the thickness of the floor insulation board, ranging from 30 to 80 mm, λ w ,λ r ,λ f are the thermal conductivity of the insulation materials at the corresponding locations, in W / m·°C, c w 、c r 、c f is the unit volume cost, in yuan / cubic meter, A w 、A r 、A f They are the wall, ceiling and ground areas respectively, in square meters.

[0061] The constraints are expressed as:

[0062] g1(d w )=40-d w ≤0;

[0063] g2(d w )=d w -120≤0;

[0064] g3(d r)=60-d r ≤0;

[0065] g4(d r )=d r -140≤0;

[0066] g5(d f )=30-d f ≤0;

[0067] g6(d f )=d f -80≤0;

[0068]

[0069] Where g1 to g6 are the thickness constraints of the insulation board, g7 is the lower limit constraint of the thermal resistance value, g8 is the upper limit constraint of the energy consumption, and Q max is the maximum allowable heat loss in watts.

[0070] The Pareto optimization algorithm is used to solve this multi-objective optimization problem. The Pareto optimal solution set P * Defined as:

[0071]

[0072] Where Ω is the feasible solution space, F(x) is the objective function vector, and < indicates the Pareto dominance relationship.

[0073] The solution process adopts the weighted sum method to construct a single objective function:

[0074]

[0075] In the formula, ω is the weight coefficient, which ranges from 0 to 1. are the maximum and minimum values of each objective function, respectively.

[0076] By varying the weight coefficient ω, a Pareto front curve was generated to identify the solution with the best overall performance. Ultimately, the optimal thicknesses for the wall insulation board, roof insulation board, and floor insulation board were determined to be 60-80 mm, 80-100 mm, and 40-60 mm, respectively, meeting the design requirement of a thermal resistance of at least 2.0 m2 / °C / W. The core purpose of this step was to determine the optimal insulation thickness configuration through scientific calculations, balancing insulation effectiveness with economic cost, and providing clear parameters for subsequent material preparation.

[0077] The specific implementation method of step S02 is to pre-treat the aluminum silicate fiber, dry it at 105 degrees Celsius for 2 to 4 hours to remove adsorbed moisture, and sieve it through a 40-mesh sieve to ensure uniform particles. Then, 70 parts by mass of the dried aluminum silicate fiber, 20 parts by mass of wollastonite, and 10 parts by mass of light calcium carbonate are weighed and placed in a high-speed mixer for dry mixing. The speed is set to 800 to 1000 rpm and the mixing time is 5 to 8 minutes to ensure that the three powders are fully mixed. Afterwards, an oxidized cellulose solution is prepared, 5 parts by mass of oxidized cellulose is taken, and 45 parts by mass of pure water at a temperature of 60 to 70 degrees Celsius is slowly added, and a low-speed stirrer with a speed of 300 to 400 rpm is used to stir for 15 to 20 minutes until it is completely dissolved to form a transparent viscous solution. The prepared oxidized cellulose solution is gradually added to the dry-mixed powder at a solid-liquid ratio of 1:5. At the same time, a high-speed stirrer is started with a speed set at 1200-1500 rpm for 10-15 minutes until a uniform slurry with no obvious agglomeration and good fluidity is formed. The uniformity of the slurry mixing can be evaluated by the coefficient of dispersion (CV):

[0078]

[0079] Where σ is the sample standard deviation, μ is the sample average, the smaller the CV value, the more uniform the mixing, and the acceptance standard is CV ≤ 5%.

[0080] The calculation method of stirring power P is:

[0081] P = 2π·n·M;

[0082] Where n is the stirring speed in revolutions per second, and M is the stirring torque in Newton meters, which is monitored in real time using a torque meter. This step fully utilizes the bonding properties of oxidized cellulose and the thermal insulation performance of aluminum silicate fibers. High-speed dispersion technology is used to achieve uniform distribution of the components, laying the foundation for the subsequent formation of a microporous structure. The uniformity of the slurry significantly affects the thermal conductivity of the final insulation board. Insufficient stirring, resulting in uneven material, can increase the thermal conductivity by 15-25%.

[0083] The specific implementation method of step S03 is to first prepare a silicone-modified polyurethane emulsion, ensuring that its solid content is 40-50%, its pH value is 7.0-8.0, and its viscosity is 500-1000 mPa·s. Then, 3 parts by mass of the silicone-modified polyurethane emulsion is diluted with pure water in a ratio of 1:3 to form a dilution with a mass fraction of 10%. The diluted silicone-modified polyurethane emulsion is then slowly added to the slurry prepared in step S02, controlling the addition rate to 50-80 ml per minute, while maintaining the stirrer speed at 800-1000 rpm and the stirring time for 5-8 minutes. During the stirring process, the viscosity of the slurry is monitored to ensure that the viscosity is within the range of 1500-2500 mPa·s. Subsequently, 2 parts by mass of a foaming agent are weighed, which is azodicarbonamide with a particle size of 10-30 microns and a purity greater than 99%. Sprinkle the foaming agent evenly onto the surface of the slurry, quickly turn on the high-speed stirrer, increase the speed to 1500-1800 rpm, and stir for 3-5 minutes until the foaming agent is completely dispersed, no visible particles are left, and a uniform microporous precursor is formed. This step enhances the flexibility and hydrophobicity of the material by adding silicone-modified polyurethane emulsion as a plasticizer, while introducing the foaming agent to prepare for the subsequent formation of the microporous structure. The amount of plasticizer added is controlled at around 3%. Too low will increase the brittleness of the finished product, while too high will reduce the thermal insulation performance. The optimal addition amount is determined by rheological testing.

[0084] The specific implementation method of step S04 is to prepare the mold first, and select a stainless steel or aluminum alloy mold with a smooth inner wall. The mold size is determined according to the design requirements of the final product. Generally, the aspect ratio is controlled between 1.2 and 1.5, and the thickness is consistent with the optimization result of step S01. Then a layer of release agent is evenly coated on the inner wall of the mold. The release agent is a silicone oil-based substance, and the coating thickness is controlled at 0.1 to 0.2 mm. Then, the microporous precursor prepared in step S03 is fully stirred for 30 to 60 seconds to ensure uniformity, and then poured into the mold in a continuous and slow manner, taking care to avoid the introduction of bubbles, and the pouring height does not exceed 5 cm. Use a vibration platform to vibrate the mold injected with the microporous precursor, with a vibration frequency of 50 to 60 Hz and a vibration time of 30 to 60 seconds. The purpose is to eliminate possible large bubbles and spread the slurry evenly. The mold after pouring is transferred to a drying room with a temperature of 40-50 degrees Celsius and a relative humidity of 60-70% for 12-24 hours of constant temperature drying. The surface condition of the sample is regularly checked until the surface solidifies and the moisture content drops below 10%. During the drying process, the water evaporation rate R can be calculated using the following formula:

[0085] R=k·(p s -p a )·A;

[0086] Where R is the water evaporation rate in kg / h, k is the mass transfer coefficient in kg / m2·h·Pa, and p is the water evaporation rate in kg / m2·h·Pa. s is the partial pressure of water vapor on the sample surface, in Pascals, p a is the ambient water vapor partial pressure in Pa, and A is the exposed surface area in square meters. The change of the water content W in the sample over time can be expressed as:

[0087]

[0088] Where W(t) is the moisture content at time t, W0 is the initial moisture content, m0 is the initial mass of the sample in kilograms, and t is the drying time in hours. This process uses a slow drying principle to avoid cracking and warping caused by excessive drying. The drying temperature should not exceed 50 degrees Celsius, otherwise it will cause premature decomposition of the foaming agent and affect the subsequent formation of the microporous structure.

[0089] The specific implementation method of step S05 is to first let the dried semi-finished product stand at room temperature for 1 to 2 hours to uniformize the temperature and prevent deformation caused by thermal stress. Then carefully remove the semi-finished product from the mold, and avoid applying excessive pressure during the operation to prevent damage to the internal structure. The surface of the semi-finished product taken out should be flat, with no obvious defects on the edges. If there are small defects, they can be slightly trimmed with sandpaper. Then put 5 to 10 parts by mass of microcrystalline cellulose with a fiber length of 20 to 50 microns into the drying oven. After mixing evenly, place the semi-finished product in an oven at a temperature of 80 to 90 degrees Celsius for heat treatment, and control the heating rate at 10 to 15 degrees Celsius per hour to avoid cracking caused by sudden temperature changes. Maintain constant temperature heat treatment for 4 to 6 hours. At this stage, the foaming agent decomposes to produce nitrogen, forming a uniformly distributed microporous structure. At the same time, the microcrystalline cellulose undergoes an interfacial cross-linking reaction with the inorganic matrix, significantly enhancing the stability of the material structure. The formation of micropores during the heat treatment follows the foam chemical kinetic equation, which is specifically expressed as:

[0090]

[0091] Where N(r, t) represents the number density of bubbles with radius r and time t, and the unit is per cubic meter·micrometer, k d is the decomposition rate constant of the foaming agent, the unit is 1 / second, and the value range is 10 -4 ~10 -3 , C a is the concentration of foaming agent, in kg / m3, E ais the activation energy, in J / mol, ranging from 100 to 150 kJ / mol, R is the gas constant, with a value of 8.314 J / mol·K, T is the absolute temperature, in K, γ is the surface tension, in N / m, ranging from 0.03 to 0.05 N / m, η is the material viscosity, in Pa·s, ranging from 10 3 ~10 5 Pa·s, D is the gas diffusion coefficient, the unit is square meter / second, the value range is 10 -10 ~10 -8 square meters / second.

[0092] The bubble growth process is described by the pressure balance relationship:

[0093]

[0094] Where p g is the gas pressure inside the bubble, in Pascals, p a is the ambient pressure in Pa, and the last item represents the viscous resistance.

[0095] The stability of the bubble is determined by the critical radius r c judge:

[0096]

[0097] In the formula, when r <r c When r>r c When the bubble is larger, it tends to continue to grow.

[0098] The above parameters are obtained through experimental methods such as differential scanning calorimetry, rheological testing, and interfacial tension measurement. Finally, a closed bubble structure with a diameter of 2 to 10 microns is formed. The uniformity of bubble distribution directly affects the thermal insulation performance. After the heat treatment is completed, it is naturally cooled to room temperature at a rate not faster than 20 degrees Celsius per hour to avoid the formation of microcracks caused by thermal stress. Temperature control of this process is crucial. Too low a temperature will lead to insufficient foaming, and too high a temperature will cause the bubbles to over-expand or even rupture. The optimal temperature range is determined by differential scanning calorimetry.

[0099] The specific implementation method of step S06 is to first prepare a nano-silica solution, take 15 parts by mass of nano-silica with a particle size of 10 to 50 nanometers, a specific surface area of 150 to 300 square meters per gram, and a purity greater than 99.5%, disperse it in 85 parts by mass of pure water, add 0.5 to 1.0 parts by mass of a dispersant, and use ultrasonic dispersion technology for treatment with an ultrasonic power of 300 to 500 watts for 15 to 30 minutes until a stable dispersed solution is formed. The dispersion stability of the nanoparticles can be characterized by the zeta potential:

[0100]

[0101] Where μ e is the electrophoretic mobility, in square meters / volt-second, ε is the dielectric constant of the dispersion medium, ζ is the Zeta potential, in volts, and η is the viscosity of the medium, in Pascal-seconds. The |ζ| value of the stably dispersed nanosolution should be greater than 30 millivolts. High-pressure airless spraying equipment is then used to coat the surface of the heat-treated insulation board. The spraying pressure is controlled at 0.8 to 1.2 MPa, the distance between the nozzle and the surface of the insulation board is maintained at 15 to 25 cm, and the nozzle is moved at a constant speed to ensure uniform coating, and the thickness is controlled at 1 to 2 mm. After coating, the insulation board is placed in an environment with a temperature of 25 to 30 degrees Celsius and a relative humidity of 50 to 60% to dry for 8 to 12 hours, avoiding dust contamination and mechanical vibration during this period. During the drying process, the coating curing follows the diffusion-controlled model:

[0102]

[0103] Where X is the degree of curing, dimensionless, ranging from 0 to 1, k c is the curing rate constant, expressed in 1 / hour, and n is the reaction order, typically 1-2, measured using a simultaneous thermal analyzer. During the drying process, a dense network of nanosilica particles forms, firmly bonding to the insulation board matrix and ultimately forming a protective layer that is both fireproof and water-resistant. This coating effectively increases the surface hardness of the insulation board to 5-6 on the Mohs scale, while also providing excellent water resistance with a water contact angle greater than 120 degrees, significantly extending the insulation board's service life in high-humidity environments.

[0104] The specific implementation of step S07 is to first determine the precise dimensional requirements of the insulation board based on the baking room design drawings, including standard board sizes and non-standard sizes for special locations. Appropriate cutting equipment is then selected, typically a diamond wire saw or a high-pressure water jet cutter. The former is suitable for straight-line cutting with an accuracy of ±1 mm, while the latter is suitable for curved or irregular shapes with an accuracy of ±2 mm. A cutting plan is developed, adhering to the principle of maximizing material utilization. A dynamic programming algorithm is used to calculate the optimal cutting path to reduce waste. The cutting optimization problem can be expressed as:

[0105]

[0106] Constraints:

[0107] Where Z is the objective function, which represents the total value, and v i is the unit value of the i-th specification plate, x i is the number of plates of the i-th specification, l iis the length of the i-th specification plate, L is the length of the raw material, δ is the allowable cutting error, usually 1 to 3 mm, and n is the number of specifications.

[0108] The optimization problem is solved by dynamic programming, and the state transition equation is:

[0109]

[0110] Where f(j) represents the maximum value that can be obtained for a material of length j. Sheets are cut according to the cutting plan, with a cutting speed of 50 to 80 mm / min to prevent edge cracking due to excessively fast cutting or overheating that damages the microporous structure due to excessively slow cutting. After cutting, the cut surface is treated by lightly polishing it with fine-grit sandpaper (320 to 400 grit) to remove burrs and minor defects, ensuring a flatness error of no more than 0.5 mm / m. The cut sheets are dimensional inspected with a sampling rate of no less than 10%, ensuring dimensional accuracy within a range of plus or minus 3 mm.

[0111] The specific implementation method of step S08 is to first check the installation surface to ensure that the flatness error of the wall, top plate and ground surface does not exceed 5 mm / m, and clean the surface to remove impurities such as dust and oil stains that affect bonding. Then prepare the inorganic adhesive, select water glass inorganic glue, add 10 to 15 parts by mass of wollastonite as reinforcing filler, stir evenly to form a paste, and control the setting time to 30 to 40 minutes. Use a toothed scraper to evenly apply the inorganic adhesive on the installation surface, with a thickness of 3 to 5 mm and a tooth spacing of 8 to 10 mm to ensure that the coverage is not less than 80%. Install the cut insulation board to the surface coated with adhesive according to the designed position. During installation, the board should be lightly pressed and slightly moved to ensure full contact and bonding. Use a spirit level to check the horizontal and vertical degree of the installed board, with an allowable error of no more than 3 mm / m. The treatment of the joints between the panels is crucial. The joint width should be controlled at 3 to 5 mm. First, fill the joint with a fireproof sealing strip, and then cover the joint surface with an inorganic fireproof sealing strip with a width of 80 to 100 mm to form a double sealing structure. The thermal bridge effect at the joint can be calculated using the following formula:

[0112]

[0113] Where ψ is the linear thermal bridge heat transfer coefficient, in W / m·°C, L 2D is the linear heat transfer coefficient obtained from the two-dimensional heat flow calculation, in W / m·°C, U j is the heat transfer coefficient of the jth component, in W / m2·°C, l j is the length of the jth component in the calculation model, in meters, and m is the number of components.

[0114] L 2DThe two-dimensional steady-state heat conduction equation is solved by finite element analysis software and the following is obtained:

[0115]

[0116] Where λ is the thermal conductivity in W / m·°C, T is the temperature in degrees Celsius, and x and y are spatial coordinates in meters. The boundary conditions are of the third type:

[0117]

[0118] Where n is the direction of the boundary normal, h is the surface heat transfer coefficient, and the unit is W / m2·°C, T a =Ambient temperature, expressed in degrees Celsius. Thermal bridge analysis ensures that the thermal bridge effect coefficient of joints is less than 0.05 W / m·°C, and local reinforcement measures are implemented where necessary. This step significantly reduces thermal bridge effects through meticulous installation techniques and joint treatment technology, improving overall insulation performance and fire safety.

[0119] The specific implementation method of step S09 is to first close all normal openings of the baking room, including doors, windows, vents, etc., so that the baking room is in a completely closed state. Then install air tightness testing equipment, including variable frequency fans, differential pressure gauges, flow meters, etc. The maximum air volume of the variable frequency fans is not less than 5000 cubic meters / hour, the accuracy of the differential pressure gauge is not less than 1 Pa, and the accuracy of the flow meter is not less than 0.1 cubic meters / hour. According to the air tightness test principle of the wind pressure method, a pressure difference of 50 Pa is formed inside and outside the baking room. This pressure value simulates the actual use state under medium wind speed conditions. Keep the pressure stable for 15 to 20 minutes, record the compensating air flow required to maintain the pressure difference, and use an infrared thermal imager to scan the periphery of the baking room to detect temperature anomalies. The formula for calculating the air leakage rate is:

[0120]

[0121] Where q 50 V is the air leakage rate in cubic meters per hour and square meters. 50 A is the gas flow rate under a pressure difference of 50 Pa, in cubic meters per hour. E It is the external surface area of the enclosing structure, in square meters.

[0122] The relationship between air flow and pressure difference follows a power law relationship:

[0123] V=C·Δp n ;

[0124] Where V is the air flow rate in cubic meters per hour, C is the air flow coefficient, Δp is the pressure difference in Pa, and n is the flow index, which is usually 0.6 to 0.7. The least squares fitting method is used to fit the test data at multiple pressure points to obtain:

[0125] lnV=lnC+n·lnΔp;

[0126] Where n and lnC are fitting parameters. According to the fitting results, the gas flow rate V under 50 Pa pressure difference is accurately calculated. 50 Ensure that the air leakage rate does not exceed the standard of 0.5 cubic meters per hour per square meter. This standard is determined with reference to the airtightness requirements of passive houses. Mark and repair the temperature anomalies detected by the infrared thermal imager. Generally, high-elastic sealant is used for local reinforcement. After repair, airtightness testing is carried out again until the requirements are met. Airtightness testing is a key step in evaluating the overall performance of the thermal insulation enclosure structure. Through the dual means of airtightness testing and thermal bridge detection, it is ensured that the final dense baking room has excellent thermal insulation performance and energy utilization efficiency.

[0127] To better understand and implement the present invention, Example 2 of a specific application scenario of the present invention is provided below: At a tobacco research base, researchers conducted a systematic study and applied implementation of an inorganic plasticized microporous thermal insulation enclosure structure for a clean, energy-intensive flue-curing barn. First, local environmental data was collected, including an annual average temperature of 12.5°C, an average daily temperature difference of 15.8°C during the flue-curing barn's use period (July to September), and a maximum temperature difference of 28.3°C. Based on this data, the researchers determined the dimensions of the experimental flue-curing barn to be 6.5 meters long, 3.8 meters wide, and 2.6 meters high, with a construction area of 24.7 square meters. Using the method of step S01, the researchers established a multi-objective optimization model with input parameters including thermal conductivity coefficients of 0.81 W / m·°C for the wall, 0.75 W / m·°C for the roof, and 1.28 W / m·°C for the ground base material, respectively, and unit volume costs of 580 yuan / m³, 620 yuan / m³, and 420 yuan / m³, respectively. By solving the optimization model, the optimal insulation thickness configuration is determined as shown in Table 1:

[0128] Table 1 Optimization results of insulation board thickness

[0129]

[0130] According to the optimization results, the researchers prepared an inorganic plasticized microporous insulation board according to the method of steps S02 to S04. The specific formula is 70 parts by mass of aluminum silicate fiber (average fiber length 85 microns), 20 parts by mass of wollastonite (specific surface area 18,500 square meters / kg), 10 parts by mass of light calcium carbonate (purity 99.2%), 5 parts by mass of oxidized cellulose (molecular weight 25,000 Daltons, viscosity 560 mPa·s) as a binder, and pure water is added at a solid-liquid ratio of 1:5 and stirred for 12 minutes. Subsequently, 3 parts by mass of silicone-modified polyurethane emulsion (solid content 45%, pH value 7.4) is added as a plasticizer according to step S03, stirred for 6.5 minutes, 2 parts by mass of azodicarbonamide foaming agent (particle size 22 microns) are added, and stirring is continued for 4 minutes to form a microporous precursor. The slurry performance parameters are shown in Table 2:

[0131] Table 2 Performance parameters of microporous precursor slurry

[0132] Performance indicators Measured value Test Method Standard requirements Viscosity (mPa·s) 1850 Rotational viscometer 1500～2500 Flowability (mm) 168 Jumping platform mobility method ≥150 pH 7.6 pH meter 7.0～8.0 Solid content (%) 38.5 Drying method 35～45 Coefficient of dispersion (%) 3.8 Multi-point sampling method ≤5.0

[0133] After the slurry was injected into the mold, it was dried at 45°C and 65% relative humidity for 18 hours, then demoulded according to step S05 and heat treated at 85°C for 5 hours. The researchers used differential scanning calorimetry to monitor the thermal changes during the foaming process and determine the foaming agent decomposition rate constant k d 4.8×10 -4 / second, activation energy E a The microstructure of the insulation board obtained by heat treatment is shown in Table 3:

[0134] Table 3 Microstructure characteristics of insulation board

[0135] parameter Numerical Detection method Average pore size (μm) 6.2 Scanning electron microscopy Pore size distribution range (μm) 2.1～9.8 Scanning electron microscopy Porosity (%) 78.5 Fluid replacement Closed cell rate (%) 92.3 Gas permeation method <![CDATA[Density (kg / m 3 )]]> 215 Mass-volume method

[0136] Subsequently, the researchers used a nano-silica solution (particle size 38 nanometers, specific surface area 225 square meters / gram) with a mass fraction of 15% to coat the surface of the insulation board with a thickness of 1.5 mm to form a fireproof and water-resistant protective layer according to step S06. After testing, the Zeta potential of the coating was -42 millivolts, indicating good dispersion stability. According to steps S07 to S08, the researchers used a dynamic programming algorithm to optimize the cutting scheme, and the material utilization rate reached 91.5%. The insulation boards were installed in various parts of the baking room using a water glass inorganic glue (with 12 parts by mass of wollastonite). The joints were treated with an inorganic fireproof sealing strip with a width of 90 mm. The finite element analysis determined that the thermal bridge effect coefficient of the joints was 0.038 watts / meter·degrees Celsius, which was lower than the design standard of 0.05 watts / meter·degrees Celsius. After completing the installation, the researchers conducted an airtightness test according to step S09. Under a pressure difference of 50 Pa, the leakage rate was 0.32 cubic meters / hour·square meter, which met the design requirements. The performance comparison of thermal insulation enclosure structure is shown in Table 4:

[0137] Table 4 Comparison of thermal insulation enclosure performance

[0138] Performance indicators Traditional insulation structure Thermal insulation structure of the present invention Improvement ratio (%) Thermal conductivity (W / m·℃) 0.085 0.042 50.6 Compressive strength (MPa) 0.62 0.98 58.1 Fire rating Level B1 A-level - Water absorption (%) 4.8 0.5 89.6 Service life (years) 8～10 ≥15 ≥50.0 Energy consumption (kWh / kg tobacco leaf) 2.83 1.65 41.7

[0139] The above examples demonstrate that the inorganic plasticized microporous thermal insulation enclosure preparation method for clean, energy-intensive flue-curing barns employed in the present invention represents a significant improvement over conventional methods. Traditional insulation structures primarily utilize organic insulation materials such as polystyrene foam boards or composite silicate materials, which suffer from issues such as high thermal conductivity, insufficient compressive strength, poor fire resistance, easy water absorption, and a short service life. The present invention, however, determines the optimal insulation thickness configuration through multi-objective optimization, utilizes inorganic plasticized microporous technology to prepare the insulation board, and enhances its fire and water resistance through a surface nano-silica coating. This achieves the combined effects of a 50.6% reduction in thermal conductivity, a 58.1% increase in compressive strength, an 89.6% reduction in water absorption, an over 50% extension in service life, and a 41.7% reduction in flue-curing energy consumption. In particular, the present invention utilizes foam chemical kinetics to control the microporous structure, enabling the insulation board to achieve both high strength and high thermal insulation performance while maintaining its lightweight properties. This effectively addresses the issues of traditional insulation structures prone to thermal bridge formation and poor airtightness, providing key technical support for the widespread application of clean, energy-intensive flue-curing barns.

[0140] It should be noted that the variables involved in the present invention are explained in detail as shown in Tables 5 and 6 below.

[0141] Table 5 Variable Explanation Table (Part 1)

[0142]

[0143] Table 6 Variable Explanation Table (Part 2)

[0144]

[0145]

[0146] The above description is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed by the present invention, which should be covered by the scope of protection of the present invention.

Claims

1. A method for preparing a clean energy-intensive baking room inorganic plasticized microporous thermal insulation enclosure, characterized in that: include: Construct a multi-objective optimization model to determine the thickness of the insulation board; preparing a slurry formed by mixing aluminum silicate fiber, wollastonite, and light calcium carbonate; Adding silicone-modified polyurethane emulsion as a plasticizer and foaming agent to form a microporous precursor; The microporous precursor is dried in a mold and then demolded for heat treatment, so that the foaming agent produces nitrogen through thermal decomposition reaction to form a uniform microporous structure, while triggering the interfacial cross-linking reaction between microcrystalline cellulose and the inorganic matrix; a nano-silica solution is coated on the surface of the insulation board to form a fire-proof and water-resistant protective layer; the insulation board is cut and installed, and the joints are treated with inorganic fire-proof sealing strips.

2. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 1 is characterized in that: The step of constructing a multi-objective optimization model to determine the thickness of the insulation board is specifically to construct a multi-objective optimization model based on the thermal balance calculation results of the dense baking room, with maximizing thermal resistance and minimizing construction costs as objective functions, and with structural stability, space limitations, and safety performance as constraints, and apply the Pareto optimization algorithm to solve it.

3. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 2, characterized in that: The thickness of the insulation board includes the thickness of the wall insulation board, the thickness of the roof insulation board, and the thickness of the ground insulation board. The optimal values are 60-80 mm, 80-100 mm, and 40-60 mm, respectively, meeting the thermal resistance value of not less than 2.0 square meters·degrees Celsius / watt.

4. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 3 is characterized in that: The step of preparing the slurry specifically comprises mixing aluminum silicate fiber, wollastonite, and light calcium carbonate in a mass ratio of 70:20:10, adding 5% by mass of oxidized cellulose, adding pure water in a solid-liquid ratio of 1:5, and stirring at high speed for 10 to 15 minutes to prepare a uniform slurry.

5. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 4 is characterized in that: The step of forming the microporous precursor is specifically to add 3% by mass of silicone modified polyurethane emulsion as a plasticizer to the slurry, stir for 5 to 8 minutes, add 2% by mass of foaming agent, and continue stirring for 3 to 5 minutes to form the microporous precursor.

6. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 5, characterized in that: The drying step specifically involves pouring the microporous precursor into a pre-designed size mold, coating the inner wall of the mold with a release agent, and drying at a temperature of 40 to 50 degrees Celsius for 12 to 24 hours to reduce the moisture content to below 10%.

7. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 6, characterized in that: The heat treatment step specifically involves demolding the dried semi-finished product and placing it in an oven at a temperature of 80 to 90 degrees Celsius for heat treatment for 4 to 6 hours, so that the foaming agent produces nitrogen through a thermal decomposition reaction to form a uniform microporous structure, while triggering an interfacial cross-linking reaction between the microcrystalline cellulose and the inorganic matrix, thereby enhancing the structural stability of the material.

8. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 7, characterized in that: The step of forming the fireproof and water-resistant protective layer is to coat the surface of the insulation board with a nano-silicon dioxide solution with a mass fraction of 15% after heat treatment, with a thickness of 1 to 2 mm, and dry it at a temperature of 25 to 30 degrees Celsius for 8 to 12 hours.

9. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 8, characterized in that: The microporous precursor refers to a mixture containing an unreacted foaming agent, which is subsequently heat-treated to form a closed bubble structure with a diameter of 2 to 10 microns.

10. The method for preparing the clean energy-intensive baking barn inorganic plasticized microporous thermal insulation enclosure according to claim 9, characterized in that: The organosilicon-modified polyurethane emulsion refers to a polymer emulsion prepared by copolymerization of organosilicon and polyurethane, which has hydrophobicity and flexibility, and can make the insulation board have both waterproof and shock-resistant capabilities.

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