China's metallurgical industry will continue to develop steadily, and the growth rate will be slower in terms of quantity and scale, but higher levels are required in terms of improving quality, developing varieties and reducing energy consumption. Therefore, backward and obsolete crafts and equipment will gradually be eliminated, and advanced technology and equipment promotion and application will accelerate. For example, in the steel industry, furnaces and small blast furnaces, converters and electric furnaces will be eliminated, while continuous casting and refining will be developed and promoted at a faster rate. These conditions will provide new and good opportunities for the development of the refractory brick industry, and also put forward new and strict requirements for the quality of refractory bricks, and will lead to more intense tens of refractory brick manufacturers in China. competition. They must fight hard to survive and develop, and the decisive factors are as follows: (1) Stability and reliability of product quality; (2) Producing more efficient and competitive high-efficiency products for refractory bricks; (3) Ability to develop high-quality new products with better performance and provide good after-sales service. It is foreseeable that in the future, China's refractory brick industry will adjust its product mix and increase the output of high-efficiency products. The development of high-efficiency products based on bauxite should be accelerated to further improve their quality and reduce costs. The competition between refractory bricks and amorphous materials (including preforms) will continue in the future. The production ratio of amorphous materials will increase greatly, and high-efficiency castables will take the lead: in this respect, the micro-powder process; (preparation and application) should be a focus of research and development. Considering high temperature performance (mechanical properties, thermal shock resistance, erosion resistance and oxidation resistance), oxide and non-oxide composite materials are promising new high-quality and high-efficiency refractory bricks, which may rise in the new century. And gradually developed. This is an area worth exploring, investing in and developing. For China's refractory brick industry, the beginning of the next century will be a period of structural optimization. Refractory brick manufacturers will be re-combined and adjusted; internal structure and management will be reformed; variety structure will be changed; process and equipment will be updated; adaptability to market economy will be improved, and it is expected that China's refractory brick industry will catch up with high temperature by 2020 The pace of industrial development, and can adapt to the rhythm of the international refractory brick industry market.

The main performance of the kiln is mainly determined by the technical and economical performance of the refractories, which directly affects the investment cost, work performance, thermal efficiency, and energy consumption of the kiln. The general principle of choosing refractory materials:

1, the furnace performance and thermal characteristics. Kilns with intermittent work should use materials with low heat capacity. 2, the safe use of materials temperature, thermal conductivity, high temperature strength, chemical stability. 3, the use of life. 4, investment costs and operating maintenance costs.

In general, heavy refractory materials focus on a certain technical performance index, such as high temperature stability, chemical stability, etc.; lightweight insulation materials pay more attention to the integrated technical and economic indicators of input and operation.

When using lightweight insulation materials, it is generally determined by the thermal conductivity of the insulation material (λ) and the cost per unit volume of insulation material (Ρ). The smaller the value of the product of “λΡ”, the better. The small value of the thermal conductivity indicates that the thermal insulation material has a good thermal insulation effect and the energy cost during operation is low. The low cost per unit volume of insulation material indicates that the investment cost is low and has a good investment and economic effect. It can be selected by coordinate graphical method. The abscissa is the working temperature and the ordinate is the product of (λΡ). The curve of each material is intercepted by the safe use temperature of the material, and the material with good technical and economic performance is selected.

 The use of high alumina bauxite as the main raw material, the introduction of a small amount of ZrO2 (because ZrO2 is monoclinic and tetragonal phase transformation, can improve the product's thermal shock stability), adding a certain amount of composite binder and additives, through the control of mud The particle size distribution of the materials, and the refractory products obtained by molding and high-temperature firing become anti-stripping high alumina bricks.   The anti-stripping mechanism is due to the fact that the microstructure characteristics of ZrO2 have been determined to have anti-stripping properties.        1 There are obvious micro-cracks around the ZrO2 aggregates. The aggregates have obvious clearance and peeling from the surrounding corundum and mullite.        2 The well-developed ZrO2 aggregates are columnar and form a layered distribution in space. There are small slits between ZrO2. The size of the ZrO2 is only 1 to 5 μm, forming a channel structure. This kind of structure is superimposed on one another, with twists and turns, which is conducive to stress transmission and dispersion.        3 Mullite is well developed and fibrous. It interlaces with ZrO2 and corundum to form a composite reinforced structure. Obviously, ZrSiO4 reacts with surrounding Al2O3 when decomposed at high temperature to form ZrO2 and mullite. The presence of ZrO2 crystals prevents the growth of fibrous mullite crystals and plate-shaped corundum and is wrapped by it. Therefore, it is present around ZrO2. Chaotic state.        4 The petrographic analysis showed that the structures of corundum and mullite were staggered and ZrO2 intercalated. Among them, there were micro-cracks in the surroundings, and there were radial micro-cracks in the larger ZrO2 crystal itself and around it.        The above-mentioned structure of the anti-stripping high-alumina brick will have energy dissipation when subjected to stress, and improve the effect of thermal stability and high-temperature strength.

Taking the road of sustainable development has always been a principle issue that must be followed and adhered to in the industrial development of our country and the world.  The problem of waste of energy in industrial kilns has always existed, and heat losses generally account for about 22% to 24% of fuel consumption. Kiln insulation has received increasing attention. Conforming to the current environmental conservation sources and taking the green policy trend of sustainable development, the source of the festival has brought visible benefits to industry. Therefore, the rapid development of fire-resistant insulation material has made it widely used in industrial furnaces and high-temperature equipment industries.  1. Glass tank bottom insulation: The temperature of the bottom glass in the kiln is increased, and the glass flow increases. The method for constructing the insulation layer in the bottom of a common glass kiln tank is usually to increase the insulation layer of the bricks in the heavy refractory brick masonry or heavy indefinite refractories construction.  The bottom insulation material is generally: lightweight clay insulation bricks, fireproof clay, asbestos and other fire-resistant insulation materials.  2. Wall insulation: For the pool wall, according to the usual practice, the most serious erosion and damage is at the inclined surface and the brick seams. Before the insulation measures are taken, one should try to grind the masonry plane of the brick wall tiles to make the bricks and bricks. The gap between the two reaches the minimum size. 2 Use large-size bricks as much as possible to reduce the number of brick seams. The wall insulation material is generally a lightweight clay insulation brick.     The application of high-quality refractories determines the service life of industrial kiln furnaces and high-temperature equipment, the unit energy consumption of products and the output of products. The rapid development of fire-resistant and heat-insulating materials and the development of various new types of insulation materials have, to a certain extent, also promoted the development of industrial furnaces.

The rational manufacture and selection of lightweight high-alumina bricks are of great significance to the rational use of energy and the correct implementation of China's energy policies. Among various lightweight insulation materials, lightweight high-alumina bricks have high refractoriness and small bulk density; raw materials are abundant, and refractory bricks are inexpensive, which is an ideal heat insulation material. According to the manufacturing process, lightweight high-alumina bricks can be made by foaming or adding a person.

With the development of industrial technology, lightweight insulation refractories are developing in the direction of more high temperature resistance and thermal shock resistance, and improving the thermal shock resistance and mechanical p

We all know that insulation refractories are a kind of building materials. Generally speaking, those that are not flammable, they can be fired in a timely manner, and they will not immediately burn. It is a new type of development that can prevent or delay the fire insulation material. Potential energy-efficient building materials. Insulation refractory material refers to refractory material with high porosity, low bulk density and low thermal conductivity. It is also called lightweight refractory material. Including insulation refractory products, refractory fibers and refractory fiber products. According to the use of temperature is divided into: low temperature insulation refractory material, the use of temperature is lower than 900 °C, such as diatomite insulation bricks, expanded silica products, calcium silicate board, expanded perlite products, etc.; temperature insulation refractories, the use of temperature 900 ~ 1200 °C , Such as clay insulation firebrick, aluminosilicate refractory fiber, etc.; high temperature insulation refractories, use temperature greater than 1200 °C, such as high aluminum insulation firebrick, alumina insulation firebrick, silica insulation firebrick, alumina hollow Ball bricks, zirconia hollow ball bricks, high-alumina fire-resistant fibers, polycrystalline refractory fibers (polycrystalline alumina fibers, polycrystalline zirconia fibers, polycrystalline mullite fiber) and so on.

The main characteristics of refractories are high porosity, generally above 45%; low bulk density, generally no more than 1.5g/cm3; low thermal conductivity, most of which is less than 1.0W/(m·K). It is mainly used as insulation for industrial furnaces. It can not only reduce the heat loss of the furnace, but also reduce the heat storage of the furnace, obtain the best energy-saving effect, and reduce the weight of thermal equipment. Compared with general refractory bricks, insulation refractories have poor slag resistance, mechanical strength and wear resistance. Therefore, it is not suitable for the load-bearing structure of the furnace and direct contact with slag, charge, molten metal and other parts.

Insulating refractories differ from refractories used for long nozzles and refractories used for sliding nozzles. The production of heat-resistant and refractory products mainly uses processes that can form porous structures, such as light-weight raw materials, burn-in additives, foams, and chemicals. Law and so on. Amorphous refractory fibers, such as aluminosilicate refractory fibers, high-alumina refractory fibers, etc., are usually produced by a melt process. Polycrystalline refractory fibers, such as mullite fibers, alumina fibers, etc., are produced by the colloidal process.

Fused Cast AZS 41 Block for Glass Kiln Chinese Manufacturer are the most widely used materials both in glass contact and superstructure of glass melting furnaces. The products have passed the ISO international certified, are made of high pure material, fired at high temperature by advanced technology, with the advantages of high strength, high compression resistance, good thermal shock resistance, good performance in high temperature, good thermal conductivity, good errosion resistance and so on. Widely be used for linings of furnace in industries.

The purpose is to meet the need for high air temperature and longevity of the hot blast stove (this is very important). Understand these types of lightweight insulation bricks and carefully select insulation materials. (

Hard Magnesium Silicate Insulation Board is produced by mixing a blend of ultra-low conductivity raw materials with an inorganic polymer binder. As a finished product it retains such physical features as non-inflammability, heat insulation and sound absorption, and does not contain any hazardous substances. The finished hard magnesium silicate insulation board does not contain any silicon metal. The board can be produced as a single-step process, without the need for any finishing stages, according to the customer’s specific requirements. This, therefore, avoids environmental pollution such as large amounts of dust as a result of additional process steps. Since it has a lower thermal conductivity than other similar products the board can be used for applications such as the insulation lining of electrolytic cells for aluminium production. When compared with alumino-silicate fibre board, aluminum leakage can be significantly reduced with the use of hard magnesium silicate insulation boards in this application. Additionally, there are no harmful gas emissions during the heating-up process. The hard magnesium silicate insulation board is now the natural choice as a green and environmentally-friendly material which is completely non-toxic. Properties and Advantages: 1. High compressive strength; 2. No vapours evolved during the heating-up process, green and environmentally-friendly; 3. Low thermal conductivity; 4. High electrical resistance; 5. Good thermal resistance; 6. Ease of handling and installation; 7. Hard, stable and adequate mechanical stability; Good range of size availability, straightforward construction

Lightweight firebrick generally refers to foam bricks, and normal indoor partitions use such bricks, which will not increase the load on the floor, and the sound insulation effect is good! The strength products are made of high quality plate-like corundum and mullite as aggregates. With the compound of sillimanite as the matrix, another special additive and a few rare earth oxides are mixed and kneaded by high-pressure molding and high-temperature firing. Lightweight heat-insulating refractory bricks generally produce clay-based, high-alumina high-strength floated bead bricks, low-iron mullite, high-alumina polylight heat-insulating firebricks, and diatomaceous earth insulation firebricks. Lightweight firebrick function The bulk density of commonly used clay bricks is between 0.75-1.2g/cm3, and the actual top weight is 1.0. The advantages of lightweight firebrick: 1. Economicality: It is possible to reduce the cost of foundations, reduce the cross-section of the structure, and save the use of reinforced concrete to significantly save the construction cost of construction items. The use of lightweight bricks in the design of solid clay bricks can be reduced by more than 5%. 2. Practicality: The use of lightweight bricks can increase the use of the area, together with aerated concrete heat insulation, insulation effect is good, in the hot summer, the indoor temperature is lower than the selection of solid clay brick 2-3 °C, the use of air conditioning, down Electricity consumption. 3. Construction: Lightweight bricks have outstanding machinability. The construction is simple and convenient. Because of its large size and light weight, it can reduce labor intensity, improve construction efficiency, and shorten the construction period. Lightweight firebrick ten functions: 1. Light-weight: Light-weight bricks have a dry capacity of only 500-700kg/m*3, which is 1/4 of general concrete, 1/3 of clay, and 1/2 of hollow blocks, because their bulk density is lower than that of water. Commonly known as aerated concrete floating on the surface of the water, the use of this product in construction can reduce the weight of the building and significantly reduce the cost of constructing the building.

The mullite insulation brick usually contains impurity oxides such as TiO2, Fe2O3, CaO, MgO, K2O and Na2O, and the impurity content of mullite produced from natural raw materials is higher than that of synthetic raw materials. These impurity oxides act as fluxes in mullite, reducing the formation temperature and viscosity of the melt, increasing the amount of liquid phase generated, and increasing the dissolution rate and amount of dissolution of the melt in the solid phase, but each impurity oxide The role of the intensity of the different, of which the K2O and Na2O on the liquid phase formation temperature has the greatest impact, K2O and Na2O, respectively, the temperature of its no-variable point decreased by 513 ~ 724 °C, but also to break down the role of mullite. Among these impurity oxides, the effect of TiO2 is minimal, and only the temperature at the no-parameter point is lowered by 101 to 107°C. When the TiO2 content is small, in addition to forming a limited solid solution in the partially solid solution in mullite, and promoting mullite formation and crystal growth and growth, some of them enter the liquid phase to form vitreous bodies at high temperatures.

Fe2O3 has a certain degree of solid solubility in mullite and corundum at high temperature, forming a limited solid solution. Its solid solubility in corundum is higher than that in mullite. Due to the formation of solid solution, the crystal lattice of mullite and corundum grows. The effect of Fe2O3 on the initial melting temperature of Al2O3-SiO2 material is related to the Al2O3 content or Al2O3/SiO2 ratio in the system. When Al2O3/SiO2, the initial melting temperature is 1380 DEG C, and when Al2O3/SiO2>2.55, the initial melting temperature Increased to 1460 °C, and gradually increase with its A12O3 content. In the reducing atmosphere, Fe2O3 was reduced to FeO and desolved into the glass phase, and the initial melting temperature of the system decreased, falling to 1240°C and 1380°C, respectively.

In short, with the increase of Al2O3 content in mullite bricks, its high temperature performance is improved, while the increase of the amount of melt and the decrease of high temperature performance. Accordingly, strict control of the content of impurities, especially K2O, Na2O, and Fe2O3, is an important measure for obtaining high-performance mullite bricks. Used in the slag or gas environment containing alkalis, it has serious erosion effect on mullite bricks

The main factors influencing the service life of chrome corundum bricks include gasifier load, operating temperature, coal ash melting point, ash content, and gasifier type. The service life of the chrome corundum brick (also known as the high chrome brick) of the gasifier body and the top of the arch is generally 8000~20000h, and the service life of the slag mouth and the conical bottom high chrome brick is generally 3000~6000h. The service life of each part is Mismatches greatly affect the overall service life of the gasifier and the rhythm of the entire production, and increase operating costs. Therefore, it is of great significance to carry out relevant research and further increase the service life of high-chromium bricks. To this end, the following studies have been conducted mainly at home and abroad: (1) Improve the content of Cr2O3 in materials and optimize their resistance to slag erosion. Due to the excellent resistance to slag corrosion and resistance to slag permeation of Cr2O3 materials, increasing the content of Cr2O3 in chrome corundum bricks can effectively increase the service life of chrome corundum bricks; however, excessive Cr2O3 content will affect the sintering of products and reduce the high chrome bricks. Strength and thermal shock resistance. Therefore, while increasing the content of Cr2O3 in high-chromium bricks, attention must be paid to the problem of reduced strength and thermal shock resistance. (2) Improve the density of high chrome bricks and reduce the apparent porosity of brick surfaces. Improve the density of high chrome bricks, or use salt immersion, surface coating and other measures to fill the pores on the surface of high chrome bricks, which can effectively prevent the infiltration of slag and improve the service life of high chrome bricks. (3) Improve the strength of high chrome bricks and increase their resistance to erosion. High-chromium bricks are subjected to strong scouring of high-velocity air currents and entrained slag during use, and the brick's resistance to erosion and abrasion is directly related to its strength. The purpose of improving the strength of high chrome bricks can be achieved by optimizing the product particle size distribution, increasing the firing temperature of the product, and adding new binders and accelerants.

Insulating and fireproof mud is a heavy and lightweight fire-resistant raw material, binder and admixture, and it is a special mud for building insulation refractory products. It is divided into two types of aluminum silicate and silicon. It is well known that the apparent porosity of the heat-insulating refractory products is more than 45%, that is, the water absorption rate is large. Laying with traditional fire-resistant mudstones results in poor spreadability and poor rubbing performance, and it is difficult to ensure the ash seams and is not full. The newly developed thermal insulation refractory slurry overcomes these shortcomings and guarantees good masonry quality. Insulating refractory slurries Selling materials: heavy materials are high bauxite clinker, clay clinker, silica bricks and semi-silicon bricks, etc.: Lightweight materials are all types of insulating brick powder, hollow ball, fly ash drift Beads and beads, etc.: The binder is mainly composed of aluminum dihydrogen phosphate, dextrin, water glass and polysaccharide starch, etc.; the admixtures are lignosulfonates, polyphosphates, etc.: The plasticizers are mainly made of soft clay, swelling agents. With kyanite and silica and so on. Insulating refractory mortar particle size distribution:> 0.5mm ≤ 2%, ≤ 0.074mm 50% ~ 70%: mix ratio of clay-based heat-resistant refractory mud: clay clinker powder 40%, clay-based insulating refractory brick powder 30 %, composite soft clay powder 30% and CMC 0.2%. The bonding time is about 80S, and the dry flexural bond strength is 0.5~0.7MPa: The mix ratio of high-aluminum heat-resistant refractory mud: bauxite clinker powder 35%, high alumina heat-insulating refractory brick powder 35% , Composite soft clay powder 22%, silica powder 5% and bentonite 3%, plus binders and additives. The bonding time is 97~110S, and the flexural strength after drying and 1100°C is 0.9MPa and 3.6MPa, respectively. The mixing ratio of alumina-containing thermal insulation mud is 20% for industrial alumina powder, and the high-alumina insulation fireproof Brick powder 58%, Guangdong mud and Suzhou mud 10% each, feldspar 2%, compound binder and admixture 6%, add water to mix, its chemical composition: Al2O3 57%, SiO2 29%, Fe2O3 0.45%, RO+R2O 1.74%, loss of 3.3%. Refractoriness >1790°C. The drying and tensile strength after firing at 1000°C were 0.26 MPa and 0.31 MPa, respectively. Insulating and fireproof mud contains light materials. When stirring, it should be mixed with water for 1⁄2 of the mixing time for a few minutes, and the remaining water should be mixed evenly. The total mixing time should not be less than 20 minutes. Mix the good slurry. Should be left to stand for 0.5h before use.

 Aluminosilicate refractory fiber is a new type of fire-resistant insulation material. Statistics show that the use of aluminum silicate refractory fiber as resistance furnace refractory or insulation material can save energy consumption by more than 20%, and some up to 40%. Because the aluminum silicate refractory fiber has the characteristics of high temperature resistance, good chemical stability, and low thermal conductivity, the use of aluminum silicate refractory fiber as the lining of the resistance furnace in the non-ferrous metal casting workshop can shorten the heating time and reduce the wall temperature and energy consumption. . Aluminum silicate fiber has

Refractory bricks made of sintered or fused mullite as the main raw material may all be mullite, mullite may also be partially used, and part of corundum may be used as raw material. The former becomes mullite refractory bricks, the latter known as corundum mullite refractory bricks or corundum mullite bricks. Mullite refractory brick production process and the same high alumina brick, ingredients by mixing, molding, drying and firing several processes. Firing temperature and the ingredients, raw materials, purity and performance requirements of the refractory brick, usually 1500 ~ 1700 ℃.

       Mullite refractory bricks and corundum mullite bricks have the advantages of high softening temperature, low creep rate and good thermal shock resistance, which are widely used in blast furnace, glass furnace, CDQ and furnace On the kiln. Mullite refractory bricks are easily attacked by alkaline refractory bricks at high temperatures. In addition, at high temperatures, mullite can react with water vapor to form Al2O3 and get damaged.   Therefore, mullite refractory bricks should not be used for a long time in the environment with high alkaline residue and high water vapor content.

       In addition to mullite and its composite refractory bricks with corundum, mullite can also be used with other materials to form refractory bricks to improve its properties, such as zirconium mullite bricks, mullite-SiC bricks and the like. The so-called zirconium mullite refractory brick is mullite - zirconia composite. However, since zirconia is expensive, zirconium mullite clinker or refractory bricks are often produced by reacting Al2O3 or alumina with zircon in actual production.

       Such refractory bricks and raw materials manufacturing methods include electrofusion and sintering method. The aluminum-zirconium-silicon (AZS) refractory bricks made by electric melting are obtained by calcining Al2O3 and ZrSiO4 ingredients to obtain zircon-mullite clinker, then crushing, mixing, shaping and firing to obtain zirconium mullite refractory bricks, That is sintered AZS brick.

       When using bauxite as a raw material, it is most common to introduce ZrSiO4 into the high alumina bricks to increase the thermal shock resistance of the high alumina bricks, the so-called "anti-spalling high alumina bricks." ZrO2 generated by the reaction is dispersed in mullite and corundum. Due to the phase transition of ZrO2 during heating and cooling, microcracks are generated around the ZrO2 particles to improve their thermal shock resistance. Sintered AZS refractory bricks are commonly used in glass kilns.

Brick manufacturers analyze the factors that lead to the erosion of glass furnace refractory bricks: Glass melting furnaces are constructed from a variety of refractory materials. Different refractory materials used in different parts. Such as: direct contact with the liquid glass parts, the upper space and regenerative parts of the site. Production, due to erosion of these parts of different conditions, refractory erosion are also different. Firebrick erosion directly affects the life of the melting furnace, affecting the glass production, quality and energy consumption. Melting workers to understand the erosion of refractory bricks, no doubt on the production of great significance. First, the melting furnace refractory bricks under erosion conditions Furnace refractory bricks under erosion conditions, in general, should be from the temperature conditions, chemical erosion conditions, physical erosion conditions and time conditions to consider. These four conditions in the erosion of refractory bricks can not exist alone, must be a combination of several conditions. Such as brick heating or cooling process, which is the temperature and time of the two conditions, including both the rate of heating or cooling, but also the maximum temperature and the holding time, chemical etching conditions to remove the type and number of etchants, the temperature level, sustained The length of time and the number of times have a great impact; physical erosion conditions as well. Often physical erosion and chemical erosion often coexist. So in the glass melting furnace, the result of these four conditions together determine the rate of firebrick erosion. The conditions under which the refractory bricks are eroded are the same for different parts of a furnace. The other three conditions are very different, each with its own special law.