A heat storage material and a preparation method thereof

Abstract

A heat storage material and a preparation method thereof, which are composed of the following materials mixed together: silicon powder: 1-5 parts; aluminum source: 20-30 parts; calcium source: 10-30 parts; cement: 30-40 parts; acid: 0.2-0.5 parts; organic matter: 2-4 parts. In this application, silicon powder is used to adjust the heat storage material, and acid is used to promote the mixing and combination of substances, so as to ensure the strength and stability of the obtained heat storage material, and ensure that it has high mechanical strength and thermal shock resistance in its use environment.

Description

Technical Field

[0001] The present application relates to a heat storage material and a preparation method thereof. Background Art

[0002] Heat storage materials are widely used in industrial boilers fueled by gas, such as regenerative heating furnaces in the iron and steel industry, non-ferrous metals and other industries. In the heat storage chambers of such boilers, hot and cold gas exchanges generally occur frequently to recover heat from high-temperature gases and use it to heat low-temperature gases. The temperature difference on both sides generally exceeds 100 °C. Therefore, a large amount of heat storage carriers need to be filled in the heat storage chamber to increase the heat capacity of the entire heat storage chamber. For heat storage carriers, they need to have a large heat capacity and good thermal shock resistance.

[0003] Currently, the heat storage carriers in industry are mainly spherical, with advantages such as good thermal shock stability, large heat storage capacity, high strength, easy cleaning, and recyclability. The synthesis methods are generally divided into two types. One is to process the raw material powder and then roll it into balls in a ball-making machine; the other is to place the raw materials in a spherical mold and extrude them into shape under a certain pressure. The main problems of existing heat storage materials are the gaps between spherical materials, and in addition, they are prone to damage during use, especially the generation of surface cracks or damage due to thermal expansion and contraction. There are currently many ways to prepare heat storage balls. One method is to mix raw materials such as secondary aluminum ash, nickel iron slag, clay mineral additives, and binders in sequence, then make balls, dry them, and roast them to obtain porous ceramic heat storage balls with a rich pore structure, uniform pore distribution, good mechanical strength, and high heat storage performance. Its main feature is that the main raw materials are industrial solid waste raw materials such as aluminum ash and nickel iron slag, with low cost and high economic added value. However, its forming can only use the ball-rolling method, and its minimum size can reach a diameter of 5 mm. Another method is to use bauxite, mullite, clay, low-sodium α-aluminum oxide fine powder, silicon fine powder, phosphoric acid, aluminum dihydrogen phosphate, binder, etc. Its preparation process is simple. By using the method of mechanically pressing into embryos during the ball-making process, it only needs to be dried at 500 °C for 5 hours, eliminating the roasting process above 1000 °C, significantly reducing energy consumption. However, the 350-ton pressure ball-making machine used in its forming process is relatively complex and expensive. Therefore, it can be seen that for heat storage materials, spherical materials are easier to form, but their theoretical filling coefficient is lower, the porosity between materials is higher, and the utilization rate of the furnace volume is lower. While strip-shaped materials can have smaller particle sizes, and the heat storage material bed obtained in this way can obtain a higher filling coefficient, so that more heat storage materials can be filled in the same furnace volume, obtaining a higher furnace utilization efficiency. However, the problem with strip-shaped materials is that the wear resistance at the corners is poor and they are prone to damage. Summary of the Invention

[0004] To solve the above problems, on the one hand, the present application proposes a heat storage material, which is composed of the following materials mixed together: silicon powder: 1-5 parts; aluminum source: 20-30 parts; calcium source: 10-30 parts; cement: 30-40 parts; acid: 0.2-0.5 parts; organic matter: 2-4 parts. The present application uses silicon powder to adjust the heat storage material and uses acid to promote the mixing and combination of substances, so as to ensure the strength and stability of the obtained heat storage material and ensure that it has high mechanical strength and thermal shock resistance in its use environment.

[0005] Preferably, the calcium source is calcium hydroxide; the organic matter is sesbania powder or ethyl cellulose or guar gum powder, and the cement is calcium aluminate cement.

[0006] Preferably, the aluminum source is obtained in the following manner:

[0007] Mix the aluminum raw material with water and stir. The aluminum raw material is pseudo-boehmite or aluminum hydroxide or boehmite;

[0008] Add a modifying substance, and the addition amount is 30wt% of the aluminum raw material;

[0009] Perform a hydrothermal reaction at 100-180°C for 10-15 hours;

[0010] After filtration, drying, grinding, and screening, obtain the aluminum source;

[0011] The conditions for drying the aluminum source are 100-110°C and the reaction time is 10-12 hours. In the present application, when treating the aluminum raw material with urea, ammonium bicarbonate, or ammonium carbonate and then mixing, the mixing method of first adding and then adding an organic acid is also adopted, which strengthens the connection strength between substances and ensures the structural reliability of the subsequent obtained heat storage material.

[0012] Preferably, the modifying substance is one of urea, ammonium bicarbonate, ammonium carbonate or a mixture of any of them in any proportion.

[0013] Preferably, the acid is an equal mixture of an organic acid and an inorganic acid; the organic acid is formic acid or acetic acid or citric acid; the inorganic acid is nitric acid or phosphoric acid.

[0014] Preferably, the particle size of the silicon powder is 600-800 mesh; the particle size of the aluminum source is 80-200 mesh; the particle size of the calcium source is 200-400 mesh; the particle size of the cement is 200-400 mesh; the particle size of the organic matter is 50-80 mesh.

[0015] Preferably, the water-to-material ratio is 0.5-1.

[0016] On the other hand, the present application also proposes a synthesis method of a heat storage material, including the following steps:

[0017] First, mix the aluminum source and the calcium source, and then add the organic acid and mix well;

[0018] Then add cement and mix well;

[0019] Next, add water and inorganic acid;

[0020] Finally, add silicon powder and organic matter to obtain the raw material slurry, and use a plow mixer to mix the raw material slurry well;

[0021] Use a kneader to further mix and roll to obtain the slurry to be processed;

[0022] Extrude the slurry to be processed to obtain green blocks;

[0023] Cure the green blocks under constant temperature and humidity conditions of 60 - 80°C for 1 - 5 hours;

[0024] Dry and calcine the green blocks to obtain the heat storage material. In this application, the organic acid and inorganic acid are added separately. The organic acid is mixed with the modified aluminum source, which can strengthen the mixing with the organic matter after mixing. The inorganic acid can improve the alkaline environment inside the heat storage material to ensure the performance of the finally obtained heat storage material.

[0025] Preferably, the drying and calcining are carried out as follows:

[0026] Dry at 80 - 200°C for 2 - 10 hours;

[0027] Then calcine at 600 - 800°C for the first time for 5 - 20 hours;

[0028] Then raise the temperature to 1100 - 1500°C and calcine for the second time for 5 - 10 hours.

[0029] Preferably, the green blocks are cylindrical, with a diameter of X and a length of Y, where X ≤ Y ≤ 5X.

[0030] This application can bring the following beneficial effects:

[0031] 1. This application uses silicon powder to adjust the heat storage material, and uses acid to promote the mixing and combination of substances, thereby ensuring the strength and stability of the obtained heat storage material, and ensuring that it has high mechanical strength and thermal shock resistance in its use environment.

[0032] 2. This application treats the aluminum raw material with urea, ammonium bicarbonate, and ammonium carbonate, and when mixing, it also uses the mixing method of adding first and then adding the organic acid, which strengthens the connection strength between substances and ensures the structural reliability of the subsequent obtained heat storage material.

[0033] 3. This application adopts the method of separately adding organic acid and inorganic acid. The organic acid is mixed with the modified aluminum source, and after the mixing is completed, it can strengthen the mixing with the organic matter, while the inorganic acid can improve the alkaline environment inside the heat storage material to ensure the performance of the finally obtained heat storage material. Brief Description of the Drawings

[0034] The drawings described herein are used to provide a further understanding of this application and constitute a part of this application. The schematic embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation to this application. In the drawings:

[0035] Figure 1 It is the SEM image of the product of Example 1;

[0036] Figure 2 It is the SEM image of the product of Example 2;

[0037] Figure 3 It is the SEM image of the product of Example 3;

[0038] Figure 4 It is the SEM image of the product of Comparative Example 1;

[0039] Figure 5 It is the SEM image of the product of Comparative Example 2;

[0040] Figure 6 It is the SEM image of the product of Comparative Example 3;

[0041] Figure 7 It is the SEM image of the product of Comparative Example 4. Detailed Embodiments

[0042] To clearly illustrate the technical features of this solution, the following will elaborate on this application through specific embodiments.

[0043] This application actually discloses a heat storage material and its preparation method. For the heat storage material, it is characterized in that it is composed of the following materials mixed together:

[0044] Silicon powder: 1 - 5 parts; aluminum source: 20 - 30 parts; calcium source: 10 - 30 parts; cement: 30 - 40 parts; acid: 0.2 - 0.5 parts; organic matter: 2 - 4 parts. The calcium source is calcium hydroxide, the organic matter is sesbania powder or ethyl cellulose or guar gum powder, and the cement is calcium aluminate cement.

[0045] The aluminum source is obtained in the following manner:

[0046] Mix the aluminum raw material with water and stir. The aluminum raw material is pseudo - boehmite or aluminum hydroxide or boehmite;

[0047] Add a modifying substance in an amount of 30 wt% of the aluminum raw material;

[0048] Perform a hydrothermal reaction at 100 - 180 °C for 10 - 15 hours;

[0049] Obtain the aluminum source through filtration, drying, grinding, and sieving;

[0050] The conditions for drying the aluminum source are 100 - 110 °C for 10 - 12 hours; the modifying substance is one or any mixture in any proportion of urea, ammonium bicarbonate, and ammonium carbonate.

[0051] The acid is an equal - amount mixture of an organic acid and an inorganic acid; the organic acid is formic acid or acetic acid or citric acid; the inorganic acid is nitric acid or phosphoric acid, and the amount of the inorganic acid is calculated according to the actual content of the acid substance.

[0052] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh; the particle size of the organic matter is 50 - 80 mesh. The water - to - material ratio is 0.5 - 1.

[0053] For the synthesis method, a synthesis method of a heat storage material includes the following steps:

[0054] S1 First, mix 20 - 30 parts of the aluminum source and 10 - 30 parts of calcium hydroxide, then add 0.1 - 0.25 parts of an organic acid (formic acid or acetic acid or citric acid) and mix well;

[0055] Then add 30 - 40 parts of calcium aluminate cement and mix well;

[0056] Then add water (water - to - material ratio is 0.5 - 1) and 0.1 - 0.25 parts of an inorganic acid (nitric acid or phosphoric acid);

[0057] The aluminum source is obtained as follows:

[0058] Mix the aluminum raw material (pseudo - boehmite or aluminum hydroxide or boehmite) with water and stir;

[0059] Add a modifying substance in an amount of 30 wt% of the aluminum raw material;

[0060] Perform a hydrothermal reaction at 100 - 180 °C for 10 - 15 hours;

[0061] Obtain the aluminum source through filtration, drying, grinding, and sieving;

[0062] The conditions for drying the aluminum source are 100 - 110 °C for 10 - 12 hours; the modifying substance is one or any mixture in any proportion of urea, ammonium bicarbonate, and ammonium carbonate.

[0063] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0064] S2 Add 1 - 5 parts of silicon powder (Si) and 2 - 4 parts of organic matter (sophorose powder or ethyl cellulose or guar gum powder) to obtain a raw material slurry, and use a plow mixer to fully mix the raw material slurry for 2 hours;

[0065] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0066] S3 Use a kneader to further mix and roll for 0.5 hours to obtain a slurry to be processed; extrude the slurry to be processed to obtain a green block;

[0067] S4 Cure the green block under constant temperature and humidity conditions of 60 - 80 °C for 1 - 5 hours;

[0068] S5 Dry and roast the green block to obtain a heat storage material.

[0069] The drying and roasting are carried out as follows:

[0070] Dry at 80 - 200 °C for 2 - 10 hours;

[0071] Then roast at 600 - 800 °C for the first time for 5 - 20 hours;

[0072] Then raise the temperature to 1100 - 1500 °C and roast for the second time for 5 - 10 hours.

[0073] The green block is cylindrical, with a diameter of X and a length of Y, where X ≤ Y ≤ 5X.

[0074] Specific embodiments are as follows:

[0075] Example 1:

[0076] S101 First, mix 20 kg of aluminum source and 10 kg of calcium hydroxide, then add 0.1 kg of formic acid and mix well;

[0077] Then add 30 kg of calcium aluminate cement and mix well;

[0078] Then add water (the total water - material ratio is 0.5) and 0.1 kg of nitric acid (calculated by nitric acid content);

[0079] The aluminum source is obtained as follows:

[0080] Mix pseudo - boehmite with water and stir;

[0081] Add urea, and the addition amount is 30 wt% of the aluminum raw material;

[0082] The hydrothermal reaction is carried out at 100 °C for 15 hours;

[0083] After filtration, drying, grinding, and screening, an aluminum source is obtained;

[0084] The conditions for drying the aluminum source are 100 °C for 12 hours.

[0085] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0086] S102 Add 1 kg of silicon powder (Si) and 2 kg of sesbania powder to obtain a raw material slurry, and the raw material slurry is fully mixed for 2 hours using a plow - type mixer;

[0087] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0088] S103 Further mix and roll the slurry for 0.5 hours using a kneader to obtain a slurry to be processed; the slurry to be processed is extruded to obtain a green block;

[0089] S104 Cure the green block under constant temperature and humidity conditions at 60 °C for 5 hours;

[0090] S105 Dry and roast the green block to obtain a heat storage material.

[0091] The drying and roasting are carried out as follows:

[0092] Dry at 80 °C for 10 hours;

[0093] Then roast at 600 °C for 20 hours for the first time;

[0094] Then raise the temperature to 1100 °C and roast for 10 hours for the second time.

[0095] The green block is cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0096] The axial compressive strength is measured to be 21.4 MPa; at a constant temperature of 400 °C, saturated water vapor is introduced for 3 h, and the compressive strength is re - measured to be 20.6 MPa;

[0097] Put 10 green blocks into a closed container, rotate at 60 r / min, and switch between the front and back sides until rotating for 20 min, and measure the percentage of the worn - off material in the original mass: 0.5%, and there is almost no damage at the edge.

[0098] SEM shows Figure 1 .

[0099] Example 2:

[0100] In S201, first mix 30 kg of aluminum source and 30 kg of calcium hydroxide, then add 0.25 kg of acetic acid and mix well;

[0101] Then add 40 kg of calcium aluminate cement and mix well;

[0102] Then add water (the total water-to-material ratio is 1) and 0.25 kg of phosphoric acid (calculated based on the phosphoric acid content);

[0103] The aluminum source is obtained as follows:

[0104] Mix aluminum hydroxide with water and stir;

[0105] Add ammonium bicarbonate, and the addition amount is 30 wt% of the aluminum raw material;

[0106] Carry out hydrothermal reaction at 180 °C for 10 hours;

[0107] After filtration, drying, grinding, and screening, the aluminum source is obtained;

[0108] The conditions for drying the aluminum source are 110 °C for 10 hours;

[0109] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0110] In S202, add 5 kg of silicon powder (Si) and 4 kg of ethyl cellulose to obtain a raw material slurry, and the raw material slurry is mixed using a plow mixer for 2 hours to mix well;

[0111] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0112] In S203, use a kneader to further mix and roll for 0.5 hours to obtain a slurry to be processed; the slurry to be processed is extruded to obtain a green block;

[0113] In S204, cure the green block under constant temperature and humidity conditions at 80 °C for 1 hour;

[0114] In S205, dry and calcine the green block to obtain a heat storage material.

[0115] The drying and calcination are carried out as follows:

[0116] Dry at 200 °C for 2 hours;

[0117] Then carry out primary calcination at 800 °C for 5 hours;

[0118] Then raise the temperature to 1500 °C and carry out secondary calcination for 5 hours.

[0119] The embryo block is cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0120] The measured axial compressive strength is 19.8 MPa; at a constant temperature of 400 °C, saturated steam is introduced for 3 h, and the compressive strength is re-measured to be 19.5 MPa;

[0121] Ten embryo blocks are placed in a sealed container, rotated at 60 r / min, and the front and back are switched until rotation for 20 min. The percentage of the worn material in the original mass is measured: 0.3%, and there is almost no breakage at the edge.

[0122] SEM shows Figure 2 。

[0123] Example 3:

[0124] In S301, 25 kg of aluminum source and 20 kg of calcium hydroxide are first mixed, and then 0.2 kg of citric acid is added and mixed thoroughly;

[0125] Then 30 - 40 kg of calcium aluminate cement is added and mixed thoroughly;

[0126] Water (with an overall water-to-material ratio of 0.8) and 0.2 kg of nitric acid (calculated based on the nitric acid content) are added;

[0127] The aluminum source is obtained in the following manner:

[0128] Boehmite is mixed with water and stirred;

[0129] Ammonium carbonate is added, and the addition amount is 30 wt% of the aluminum raw material;

[0130] Hydrothermal reaction is carried out at 140 °C for 12 hours;

[0131] After filtration, drying, grinding, and screening, the aluminum source is obtained;

[0132] The conditions for drying the aluminum source are 105 °C and a reaction time of 11 hours;

[0133] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0134] In S302, 3 kg of silicon powder (Si) and 3 kg of guar gum powder are added to obtain a raw material slurry, and the raw material slurry is thoroughly mixed for 2 hours using a plow mixer;

[0135] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0136] S303 Further mix and roll the slurry to be processed for 0.5 hours using a kneader; extrude the slurry to be processed to obtain a green block;

[0137] S304 Cure the green block for 3 hours under constant temperature and humidity conditions at 70 °C;

[0138] S305 Dry and calcine the green block to obtain a heat storage material.

[0139] The drying and calcination are carried out as follows:

[0140] Dry at 140 °C for 6 hours;

[0141] Then calcine at 700 °C for 12 hours for the first time;

[0142] Then raise the temperature to 1300 °C and calcine for 8 hours for the second time.

[0143] The green block is cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0144] Measure the axial compressive strength to be 20.5 MPa; introduce saturated steam at a constant temperature of 400 °C and treat for 3 h, and re-measure the compressive strength to be 20.3 MPa;

[0145] Put 10 green blocks into a closed container, rotate at 60 r / min, and switch between the front and back sides until rotating for 20 min, and measure the percentage of the worn material in the original mass: 0.6%, and there is almost no damage at the edge.

[0146] SEM shows Figure 3 .

[0147] Comparative Example 1:

[0148] S401 First mix 25 kg of boehmite and 20 kg of calcium hydroxide, then add 0.2 kg of citric acid and mix well;

[0149] Then add 30 - 40 kg of calcium aluminate cement and mix well;

[0150] Then add water (the total water-to-material ratio is 0.8) and 0.2 kg of nitric acid (calculated based on the nitric acid content);

[0151] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0152] S402 Add 3 kg of silicon powder (Si) and 3 kg of guar gum powder to obtain a raw material slurry, and the mixing of the raw material slurry is carried out using a plow mixer and mixed well for 2 hours;

[0153] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0154] S403 Further mix and roll for 0.5 hours using a kneader to obtain the slurry to be processed; extrude the slurry to be processed to obtain green compacts;

[0155] S404 Cure the green compacts under constant temperature and humidity conditions at 70°C for 3 hours;

[0156] S405 Dry and calcine the green compacts to obtain the heat storage material.

[0157] The drying and calcination are carried out as follows:

[0158] Dry at 140°C for 6 hours;

[0159] Then calcine at 700°C for 12 hours for the first time;

[0160] Then raise the temperature to 1300°C and calcine for 8 hours for the second time.

[0161] The green compacts are cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0162] Measure the axial compressive strength to be 14.7 MPa; introduce saturated steam at a constant temperature of 400°C and process for 3 h, then re-measure the compressive strength to be 10.4 MPa;

[0163] Put 10 green compacts into a closed container, rotate at 60 r / min, and switch between the front and back sides until rotating for 20 min, and measure the percentage of the worn material in the original mass: 2.4%, and there are slight damages at the edges.

[0164] SEM shows Figure 4 。

[0165] Comparative Example 2:

[0166] S501 First mix 25 kg of aluminum source and 20 kg of calcium hydroxide, then add 0.2 kg of citric acid and 0.2 kg of nitric acid and mix well;

[0167] Then add 30 - 40 kg of calcium aluminate cement and mix well;

[0168] Then add water (the total water-to-material ratio is 0.8);

[0169] The aluminum source is obtained as follows:

[0170] Mix boehmite with water and stir;

[0171] Add ammonium carbonate, and the addition amount is 30 wt% of the aluminum raw material;

[0172] The hydrothermal reaction was carried out at 140 °C for 12 hours;

[0173] After filtration, drying, grinding, and screening, an aluminum source was obtained;

[0174] The conditions for drying the aluminum source were 105 °C for 11 hours;

[0175] The particle size of the aluminum source was 80 - 200 mesh; the particle size of the calcium source was 200 - 400 mesh; the particle size of the cement was 200 - 400 mesh.

[0176] For S502, 3 kg of silicon powder (Si) and 3 kg of guar gum powder were added to obtain a raw material slurry, and the raw material slurry was thoroughly mixed for 2 hours using a plow mixer;

[0177] The particle size of the silicon powder was 600 - 800 mesh; the particle size of the organic matter was 50 - 80 mesh.

[0178] For S503, the mixture was further mixed and rolled for 0.5 hours using a kneader to obtain a slurry to be processed; the slurry to be processed was extruded to obtain green compacts;

[0179] For S504, the green compacts were cured at a constant temperature and humidity of 70 °C for 3 hours;

[0180] For S505, the green compacts were dried and calcined to obtain a heat storage material.

[0181] The drying and calcination were carried out as follows:

[0182] Drying was carried out at 140 °C for 6 hours;

[0183] Then, it was calcined for 12 hours at 700 °C for the first time;

[0184] The temperature was then raised to 1300 °C and calcined for 8 hours for the second time.

[0185] The green compacts were cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0186] The axial compressive strength was measured to be 15.1 MPa; saturated steam was introduced at a constant temperature of 400 °C for 3 h, and the compressive strength was re - measured to be 11.7 MPa;

[0187] Ten green compacts were placed in a closed container, rotated at 60 r / min, and the front and back sides were switched until rotation for 20 min. The percentage of the worn - off material in the original mass was measured: 3.1%, and there were slight damages at the edges.

[0188] SEM shows Figure 5 。

[0189] Comparative Example 3:

[0190] First, mix 25 kg of aluminum source and 20 kg of calcium hydroxide and mix them thoroughly;

[0191] Then add 30 - 40 kg of calcium aluminate cement and mix thoroughly;

[0192] Then add water (the total water - to - material ratio is 0.8);

[0193] The aluminum source is obtained as follows:

[0194] Mix boehmite with water and stir;

[0195] Add ammonium carbonate, and the addition amount is 30 wt% of the aluminum raw material;

[0196] Conduct hydrothermal reaction at 140 °C for 12 hours;

[0197] After filtration, drying, grinding, and screening, the aluminum source is obtained;

[0198] The conditions for drying the aluminum source are 105 °C for 11 hours;

[0199] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0200] S602 Add 3 kg of silicon powder (Si) and 3 kg of guar gum powder to obtain a raw material slurry, and the mixing of the raw material slurry is carried out by a plow - type mixer for 2 hours of thorough mixing;

[0201] The particle size of the silicon powder is 600 - 800 mesh; the particle size of the organic matter is 50 - 80 mesh.

[0202] S603 Use a kneader to further mix and roll for 0.5 hours to obtain a slurry to be processed; the slurry to be processed is extruded to obtain a green block;

[0203] S604 Cure the green block under constant temperature and humidity conditions at 70 °C for 3 hours;

[0204] S605 Dry and roast the green block to obtain a heat storage material.

[0205] The drying and roasting are carried out as follows:

[0206] Dry at 140 °C for 6 hours;

[0207] Then roast at 700 °C for 12 hours for the first time;

[0208] Then raise the temperature to 1300 °C and roast for 8 hours for the second time.

[0209] The green block is cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0210] The measured axial compressive strength is 9.8 MPa; at a constant temperature of 400 °C, saturated water vapor is introduced and treated for 3 h, and the compressive strength is re-measured to be 6.4 MPa;

[0211] Put 10 embryo blocks into a sealed container, rotate at 60 r / min, and switch between the front and back sides until rotating for 20 min, and measure the percentage of the worn material in the original mass: 6.8%, and there are obvious damages at the edges.

[0212] SEM shows Figure 6 。

[0213] Comparative Example 4:

[0214] First, mix 25 kg of aluminum source and 20 kg of calcium hydroxide in S701, and then add 0.2 kg of citric acid and mix well;

[0215] Then add 30 - 40 kg of calcium aluminate cement and mix well;

[0216] Then add water (the total water - to - material ratio is 0.8) and 0.2 kg of nitric acid (calculated by nitric acid content);

[0217] The aluminum source is obtained in the following manner:

[0218] Mix boehmite with water and stir;

[0219] Add ammonium carbonate, and the addition amount is 30 wt% of the aluminum raw material;

[0220] Perform hydrothermal reaction at 140 °C for 12 hours;

[0221] After filtration, drying, grinding, and screening, the aluminum source is obtained;

[0222] The drying condition of the aluminum source is 105 °C for 11 hours;

[0223] The particle size of the aluminum source is 80 - 200 mesh; the particle size of the calcium source is 200 - 400 mesh; the particle size of the cement is 200 - 400 mesh.

[0224] Add 3 kg of guar gum powder to S702 to obtain the raw material slurry, and the mixing of the raw material slurry is carried out by a plow - type mixer for 2 hours for sufficient mixing;

[0225] The particle size of the organic matter is 50 - 80 mesh.

[0226] Use a kneading machine in S703 to further mix and roll for 0.5 hours to obtain the slurry to be processed; extrude the slurry to be processed to obtain embryo blocks;

[0227] In S704, cure the embryo blocks under the conditions of constant temperature and humidity at 70 °C for 3 hours;

[0228] The embryo block is dried and calcined to obtain the heat storage material.

[0229] The drying and calcination are carried out as follows:

[0230] Dry at 140 °C for 6 hours;

[0231] Then calcine at 700 °C for 12 hours for the first time;

[0232] Then raise the temperature to 1300 °C and calcine for 8 hours for the second time.

[0233] The embryo block is cylindrical, with a diameter of 20 mm and a length of 50 mm.

[0234] The measured axial compressive strength is 14.8 MPa; at 400 °C, saturated water vapor is introduced at a constant temperature for 3 h, and the compressive strength is measured again to be 10.3 MPa;

[0235] Put 10 embryo blocks into a closed container, rotate at 60 r / min, and switch between the front and back sides until rotating for 20 min, and measure the percentage of the worn material in the original mass: 9.5%, and the edge is severely damaged.

[0236] SEM shows Figure 7 .

[0237] The above are only the embodiments of the present application and are not used to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A heat storage material, characterized in that: Composed of the following materials mixed together: Silica powder: 1 - 5 parts; Aluminum source: 20 - 30 parts; Calcium source: 10 - 30 parts; Cement: 30 - 40 parts; Acid: 0.2 - 0.5 part; Organic matter: 2 - 4 parts; The acid is an equal - amount mixture of organic acid and inorganic acid; The aluminum source is obtained in the following manner: Mix the aluminum raw material with water and stir; Add a modifying substance, and the addition amount is 30wt% of the aluminum raw material; Then carry out a hydrothermal reaction, followed by filtration, drying, grinding, and screening to obtain the aluminum source. The temperature during the hydrothermal reaction is 100 - 180°C, and the reaction time is 10 - 15 hours; The drying conditions of the aluminum source are 100 - 110°C, and the reaction time is 10 - 12 hours; The aluminum raw material is pseudo - boehmite or aluminum hydroxide or boehmite; The modifying substance is one or any mixture of urea, ammonium bicarbonate, and ammonium carbonate in any proportion; The heat - storage material is prepared in the following manner: First, mix the aluminum source and the calcium source, and then add the organic acid and mix well; Then add the cement and mix well; Next, add water and the inorganic acid; Finally, add the silica powder and the organic matter to obtain the raw material slurry, and the mixing of the raw material slurry is carried out using a plow - type mixer for thorough mixing; Use a kneader to further mix and roll to obtain the slurry to be processed; Extrude the slurry to be processed to obtain green blocks; Cure the green blocks under constant temperature and humidity conditions of 60 - 80°C for 1 - 5 hours; Dry and calcine the green blocks to obtain the heat - storage material; The organic matter is sesbania powder or ethyl cellulose or guar gum powder.

2. The regenerative heat storage material according to claim 1, wherein: The calcium source is calcium hydroxide; The cement is calcium aluminate cement.

3. The regenerative thermal material according to claim 1, characterized in that: The organic acid is formic acid or acetic acid or citric acid; The inorganic acid is nitric acid or phosphoric acid.

4. The regenerative thermal material according to claim 1, wherein: The particle size of the silica powder is 600 - 800 mesh; The particle size of the aluminum source is 80 - 200 mesh; The particle size of the calcium source is 200 - 400 mesh; The particle size of the cement is 200 - 400 mesh; The particle size of the organic matter is 50 - 80 mesh.

5. The regenerative thermal material according to claim 1, characterized in that: The overall water - to - material ratio during the synthesis of the heat - storage material is 0.5 - 1.

6. A heat storage material according to claim 1, characterized in that: The drying and calcination are carried out in the following manner: Dry at 80 - 200°C for 2 - 10 hours; Then calcine at 600 - 800°C for the first time for 5 - 20 hours; Then raise the temperature to 1100 - 1500°C and calcine for the second time for 5 - 10 hours.

7. A heat storage material according to claim 1, characterized in that: The green blocks are cylindrical, with a diameter of X and a length of Y, where X ≤ Y ≤ 5X.

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