Ceramic fiber module is made of ceramic fiber blanket by folding and compressing. Currently, it gradually becomes the first choice for the thermal insulation of industrial furnace linings. 

Ceramic fiber module has white color and regular size. It can be directly fixed to the anchor nail on the steel plate of the furnace shell. It has good insulation performance and can improve the integrity of the furnace. It simplifies and speeds up the construction of furnaces and promotes the masonry techniques of furnaces. 

It has many advantages over the ceramic fiber blanket. 
1) During installation, after releasing the tying, the folded blankets can generate a huge stress, which makes them crowded together tightly without gaps. 
2) The flexibility of ceramic fiber blanket can compensate the deformation of the furnace shell and reduce the construction cost. At the same time, it can make up the gaps caused by the thermal changes of the different components. 
3) Since it has light weight and low thermal capacity, it can significantly reduce the energy cost during the temperature operation. 
4) Flexible ceramic fiber blanket can withstand external mechanical forces. 
5) It has good resistance to thermal shock.
6) The ceramic fiber lining requires no drying and maintenance. It can be put into use immediately after the construction is completed. 
7) It has stable chemical properties. It is not eroded by acids, bases, water, oil and vapor, except phosphoric acid, hydrofluoric acid and strong base. 

It can be used for the furnace lining insulation in the petrochemical industry, metallurgical industry, ceramic industry, glass industry, heat treatment industry and other industries. 

Zhengzhou Sunrise Refractory supplies various ceramic fiber products including ceramic fiber blanket, ceramic fiber board, ceramic fiber module, ceramic fiber vacuum formed shapes, calcium silicate board, ceramic millboard, ceramic fiber paper, ceramic fiber bulk, and ceramic fiber cloth tape, rope and yarn. 

When selecting refractories for regenerator chambers serving natural gas fired furnaces producing soda lime glass, both the functions of the refractories and the operating conditions within the checkers should be taken into consideration. 

As heat exchangers, checkers should have high thermal capacity and thermal conductivity. Basic refractories and fused cast refractories are the best solution. 

However, refractory selection also depends on the operating conditions, while the operating conditions depend on the position. According to the temperature, checkers can be divided into four zones: Top zone (from the first row to 1,350℃), Mid zone (from 1,350℃ to 1,000℃), Condensation zone (from 1,000℃ to 700℃) and Lower zone (from 700℃ to rider arches). 

Top Zone

High temperature and batches and dusts result in chemical attack and gradual corrosion of the basic refractory bricks. If refractories are magnesia bricks, the chemical attack is up to the CaO/SiO2 ratio in the waste gases. if the radio is low, forsterite (Mg2SiO4) will be formed, which results in fissures opening within the bricks. Subsequently, silica penetrates these fissures resulting in the familiar cubic breakdown of the upper checkers. If the CaO/SiO2 ratio in the waste gases is high, a liquid phase enters into the refractory causing deformation. The best solution is magnesia bricks with high Mg content, well developed MgO crystals and a direct bonded structure. Additionally, the refractories should have low iron to avoid FeO oxidation to Fe2O3 and vice versa (Fe2O3 reduction to FeO) with volume variations and resultant brick failure. 

Fused cast refractories have no surface porosity thus they are resistant to the corrosive effects of waste gases and carryover and can be used in all the checker zones. Compared to sintered refractories they are more resistant to abrasion due to their dense and homogeneous structure thus they are suitable for the top zone where there is a strong carry-over. Fused cast alumina brick is recommended for its very limited glassy phase. No glassy phase means no exudation therefore no excessive bonding with carry-over thus minimizing the risk of blockages.

Mid Zone

This zone is protected by the top checker area and temperature level is lower, thus 96% MgO with low iron and AZS brick 33# are recommended. 

Condensation Zone

This is another critical area. The waste gases contain alkaline sulphate and SO3 which will condense out in the 1,000-700℃ range. In presence of sodium sulphate, the predominance of Na2O or SO3 in the waste gases causes chemical attack. Periclase base refractories are not chemically attacked by sodium sulphate or sodium oxide but they strongly react with SO3 forming MgSO4 causing densification of the Structure. 

The chemical attack, enhanced by the presence of vanadium pentoxide when using fuel oil, breaks up the refractory and the structure densification lowers thermal shock resistance. Viable substitutes for chrome bearing refractories, which have a high resistance to condensates but cannot be used for environmental reasons, are both the spinel (MgO·Al2O3) and refractories made by periclase (MgO) and zirconia (ZrO2) having good resistance against Na2O and SO3.

When firing with natural gas, since the SO3 quantity is low, basic refractories can be used. When fused cast material is used, AZS brick is recommended. 

Low Zone

Super duty fire clay brick can be used in non severe working conditions. 90-92% magnesia brick is recommended when firing by natural gas. AZS brick 33# is also used in this zone.

Ceramic fiber blanket, also called aluminum silicate fiber blanket, is a type of insulation refractory material, featuring high strength, light weight, non asbestos and organic binder, good high temperature stability and good insulation performance. It can effectively reduce the weight of high temperature equipment and heating time and save energy. 

Ceramic fiber blanket is made of aluminum silicate with addition of auxiliary materials by the blowing technology. According to the production process, ceramic fiber blankets can be divided into two types: spun needle blanket and blown needle blanket. Especially the quality of products made by the double-side needle process is much better than common ceramic fiber blanket. 

Ceramic fiber blanket has low thermal conductivity, good insulation and low thermal capacity, thus it can effectively improve the utilization of energy. It has light weight, good thermal shock resistance and good extension. 

Ceramic fiber blanket has uniform diameter, long fiber and low shot content, which greatly improves its properties and performance. It contains no binder agent and has good reliability and stability in different environments. 

Ceramic fiber blanket is white and has regular size. It is easy to be cut and install. It can maintain good tensile strength, toughness and fiber structure in neutral and oxidizing atmosphere. Its thermal and physical properties are bot affected by oil and can be restored after drying. 

Due to its advantages, it is widely used in many fields such as lining for high-temperature reaction equipment and heating equipment in chemical industry, lining for industrial furnaces, high temperature filter material and fire protection and thermal insulation materials of high buildings. 

Fused cast refractory is a special type of refractory made by melting the raw materials in the electric arc furnace, pouring the melt into a mold and cooling the melt to solidify. It features dense structure, good corrosion resistance, low pollution to glass and long service life. Its quality and development has great influence on the service life of the float glass furnace. 

Fused cast alumina block includes alpha alumina block, beta alumina block and alpha-beta alumina block. Alpha-beta alumina block mainly consists of intertwined crystals of alpha alumina and beta alumina with just a small amount of glass phase. It has excellent corrosion resistance to glass liquid under 1350℃ and produces almost no pollution to the glass liquid, so it is widely used in working tank, feeder channels, superstructures and lipstone of the high quality glass and special glass furnaces. Beta alumina block has a higher resistance to alkali vapor, thus it has excellent thermal shock resistance and does not form molten droplets. It is the best material for molter crown, port crown,feeder channel,ect.. After the oxygen-fuel technology is applied in the glass furnaces, beta alumina block replace the silica brick to be used in the crown. 

Fused cast AZS block is the most widely used fused cast refractory used in the float glass furnace due to its good corrosion resistance to glass liquid and good high temperature performance. According to the content of ZrO2, fused cast AZS block can be divided into AZS 33#, 36# and 41#. According to the casting method, fused cast AZS can be categorized into PT AZS, QX AZS, ZWS AZS and WS AZS. 

The crystal structure of AZS mainly consists of the eutectic crystal of Al2O3 and ZrO2, scattered baddeleyite crystal and a small amount of glass phase and pores. Its micro-structure determines its performance, while its micro-structure is up to the chemical composition, melting method and annealing method.

AZS 33# is generally used in the sidewall, the bottom paving block and the superstructure. In order to eliminate the horizontal mortar joints, large sidewall block made of QX AZS 33# is used. Due to its higher ZrO2 content and better corrosion resistance, AZS 41#, especially WS AZS 41#, is always used in the demanding areas such as the feeder corner, throat, etc.. 

Fused cast high zirconia block is specially designed refractory for glass furnace application. It is made of artificial synthesis high purity raw materials through special casting process. The crystalline texture consists of baddeleyite and with the characteristics of excellent high temperature and corrosion resistance, low blister and stoning potential. These advantages can prevent liquid glass from pollution effectively. It is used in sidewall, throat cover, throat support, electrode block, and dam block parts. 

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

Zirconium-containing refractories are made of natural zircon sand or industrial ZrO2. ZrO2 has good chemical resistance. Adding ZrO2 or zircon sand into some products can improve their chemical stability. 

Typical zirconium-containing refractories such as fused cast AZS consist of eutectic crystal of baddeleyite and corundum or eutectic crystal of baddeleyite, corundum and mullite. The crystal structure makes it have great resistance to molten glass. 

Corundum refractories and high alumina refractories have good chemical stability and high temperature performance, but poor thermal stability. With the addition of ZrO2, their thermal shock resistance can be greatly improved. 

Depending on the purity requirement, zirconium-containing refractories are directly made of industrial ZrO2 and zircon sand or made by adding industrial ZrO2 and zircon sand into other materials. Sintered AZS brick for the glass furnace is made of high purity zircon sand. Fused cast AZS is made of industrial ZrO2 and zircon sand. High alumina brick with strong spalling resistance for the cement kiln is made by adding zircon sand into high alumina raw materials. 

For continuous casting refractories, except fused cast high zirconia block, other zirconium-containing refractories are always made of zirconia produced by synthesis. 

Zirconium-containing refractories generally have high melting temperature, high chemical stability, good resistant to aggressive molten metal, slags and molten glass and good thermal shock resistance. 

Zirconium-containing refractories are generally used for high-temperature critical parts, such as ladles and the slag line of continuous casting sizing nozzle and submerged entry nozzle in the metallurgy industry; the melter, superstructure, sidewalls, and throat in the glass furnaces; the transition zone and suspension preheater in the cement kiln.

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

Nowadays, refractory materials are important in the glass furnace. Refractory materials are considered mechanically and chemically high performance at temperatures above 1400℃. The requirements for refractory materials are good physical and mechanical resistance to thermal shock and to attack by molten glass. 

The refractory materials for the glass industry has made significant progress. Refractories for glass furnaces are normally based on A12O3, ZrO2, and SiO2, with or without Cr2O3. Refractories for the glass furnace are expected to have higher corrosion resistance to molten glass, no defects in glass environmental compatibility, reliable properties and improved methodology to identify origins of defects. 

The major objective in the glass furnace is to optimize the entire process by reducing the maximum temperature of melting, improving refractory performance and/or improving fuel efficiency. The required physical and chemical properties of refractories are: thermal shock resistance, corrosion resistance, controlled expansion behavior, low thermal conductivity, and adequate creep resistance. 

The fused cast manufacturing process was introduced by Fulcher in 1925 based on research conducted at Corning Glass Co. A characteristic of this manufacturing is that the materials have a low porosity. It is of great importance to the refractory, since this minimizes the glass refractory interface. Because the ZrO2 has a high melting point and has good corrosion resistance to the molten glass, fused cast AZS is widely used in the production of glass.

Fused cast AZS block generally consists of 33-41% zirconia crystals, interlocked with corundum, and minor interstitial glass. They perform well in contact with many glasses melted at 1500℃ or lower. But it can react with new developmental glasses, particularly rare earth alumino-silicates which has much higher melting temperatures, resulting in erosion of crystalline particles which cause stones in the glass. 

The chemical reactions at the surfaces of refractories may take place between molten slag, fluxing agents, and gaseous substances. The corrosion of the refractories may be due to batch carryover, volatile fluxes, and melt attack, mainly at the metal line. Erosion often follows the initial corrosion, washing away refractory grains after the original bond has dissolved. 

Fused cast AZS in contact with molten glass form a viscous silicate layer adjacent to the refractory thus restricting contact, and therefore, increasing corrosion resistance. When fused cast AZS are used in superstructures, they are exposed to high temperature combustion products. Superstructure and crown refractories are subjected to corrosive reactions with the vapor species of the batch components and batch carryover. In the melting of soda-lime glasses, the vapor species are primarily soda and sodium sulfates, while for borosilicate glasses, they are Na-tetraborate and B2O 3 predominate. 

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

The need of the glass manufacturers to maintain and improve the quality of glass and expand the service life of the glass furnace and the impact and influence of the oxygen-fuel combustion technology, promote the improvement of refractories and development of the new refractories. 

Fused cast alumina block has been widely used in the crown of the oxygen-fuel furnace, especially when manufacturing high quality glass. Before the application of the oxygen-fuel combustion technology, only β alumina block is used in the superstructure of the melting furnace. Now both β fused cast alumina block and α-β fused cast alumina block can be used in the crown of the oxygen-fuel furnace for producing TV glass, float glass and borosilicate glass. 

Fused cast AZS block has been successfully used in the crown for many years. It can be used at 1600℃ or 1650℃ and can withstand the cycle of cooling and heating well. Compared to fused cast AZS, fused cast alumina block can be used at 1700℃ and has better mechanical strength and thermal stability. 

In the past, high chromium brick was mainly used for the production of reinforced glass and sometimes in the insulation glass furnace. Now it is increasingly used in some soda-lime glass furnaces. It has much better corrosion resistance to glass and can prolong the service life of throat. Besides the throat, it is also used in the end wall, the angle brick of the feeder port. However, the chromium may color the glass liquid, thus it can not be used in the white glass furnace. It was primarily used in the colored glass furnace, but now it has been successfully used in the transparent container glass furnace.

Low glass phase fused cast AZS block has been successfully used in the superstructure. The development of the oxygen-fuel combustion technology makes it find wider application in the superstructure. Since it contains a low amount of glass phase, it has better creep resistance and the amount of exuded glass phase has been reduced to a very low level. 

Fused cast high zirconia block is a new type of refractory, mainly used in the glass contact areas in high quality glass furnace. It has a low potential of causing stones, knots and bubbles and can effectively reduce glass defects. It is also in some low alkali glass or hard borosilicate glass furnaces.

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

The quality of fused cast AZS block is related to many factors such as the chemical composition of raw materials, the melting process, the casting process and the annealing process. One of the main quality problems of the fused cast AZS block is cracking. 

Fused cast AZS block is mainly composed of baddeleyite, corundum, and a small amount of mullite, glass phase and pores. When the Al2O3 content of the raw materials exceeds 30%, the raw materials is difficult to melt and the cracking rate will increase. So before feeding the raw materials into the furnaces, the Al2O3 content must be measured to ensure it does not exceed 30%. 

The way of feeding will directly affect the melting. Once feeding all the raw materials may cause incomplete melting and the products will be easy to crack. Feeding small quantities repeatedly is better. 

If the melting temperature is too high or low, the cracking rate will increase too. Melting the raw materials at the melting temperature and then increasing the temperature can reduce the cracking rate. 

In order to reduce the residual thermal stress and avoid crack, there should be a certain amount of glass phase in the fused cast AZS to absorb the thermal stress. However, the glass phase is the weak point for the corrosion resistance of fused cast AZS. During the corrosion process, the glass phase is exuded first and replaced with the high temperature molten glass. Bubbles are released accompanying the exudation of the glass phase and pollute the glass. Fused cast AZS block (33#, 36# and 41#) contains 14-20% glass phase, thus the glass phase content has a big effect on its quality. 

During the casting process, if the casting temperature is too high, the shrinkage rate and the temperature difference between the inside and outside increase and the products are easy to crack. Before casting, stop heating for 3-5 minutes to cool the molten glass to the casting temperature and then cast, which can greatly reduce the cracking rate. 

During the annealing and cooling process, the casting products should be put in the insulating box. The initial temperature should not be too low. Then cool the products slowly. The crack rate can be reduced. 

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

Alumina (Al2O3) refractories are the part of alumina- silica group of refractories. They differs from fireclay refractories in term of Al2O3 content and normally have Al2O3 content of more than 45 %. The raw material base for these refractories are different than the fire clay bricks.

As the Al2O3 content is increased, the melting point of the refractory increases to a maximum of 2054℃ which is the melting point of pure corundum. Refractoriness increases with the increase in the Al2O3 content. The only stable compound in the system is mullite, which has a defective space lattice and decomposes into corundum and liquid phase at around 1840℃.

According to the Al2O3 content, alumina refractories can be divided into: 

Al2O3 less than 50%

Fireclay belongs to this group. Its main crystal phases are mullite and glass. It can contain free SiO2. Normally it is made from 100% fireclay. High quality fireclay is used at about 1600℃, Usually it contain 38 % to 42 % Al2O3 and are based on fireclay minerals. 

Al2O3 50% or 60%

The main crystal phases of these refractories are mullite as major phase and glass as minor phase. They can contain free SiO2. These refractories cannot be made from 100 % clay since Al2O3 content of clay are lower. They are made from minerals containing 60% Al2O3 and contains some fireclay. They can be made with bauxite and clay and can be used for temperatures greater than 1700℃. 

Al2O3 70%

The major phase of these refractories is mullite. They contain corundum, mullite and glass. They are made either from bauxitic clay or calcined bauxite and clay. They can be used for temperatures greater than 1750℃.

Al2O3 80% and 85%

These refractories are made from calcined bauxite. The main phases of these refractories are corundum as the major phase along with minor quantity of mullite and glass. 

Al2O3 90%

These refractories consist of corundum as the major phase with a minor amount of mullite and glass. Fused cast alumina block belongs to this group. It is used in contact with liquid steel or glass due to its enhanced abrasion resistance and corrosion resistance. When in contact with molten glass, it barely produces any blistering or stones. so it is ideal for the high quality glass furnace and special glass furnace. 

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including fused cast AZS block, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..

The service life of the glass furnace, energy efficiency and the quality of glass is mainly up to refractory materials. The following practices can be performed in order to select the right refractory materials and ensure longer operating life of the glass furnace. 

Consistent quality 

The quality of the refractories needs to be consistent and assured. Refractories should be bought from reliable manufacturers. Normally, reliable manufacturers can develop the correct physical properties of the refractories such as high temperature strength and correct mineral structure. Once these desired properties are achieved, the performance of the refractories will be predictable and better.

Using larger refractory blocks

The use of larger refractory blocks reduces the number of joints while constructing a furnace. Recently, large sidewall blocks made up of azs brick are used in the glass furnace to reduce the joints and the corrosion of refractories. The manufacturing of large blocks requires a high-capacity press for developing uniform property characteristics. Hence, it is necessary to consider the dimensions of the block and its properties to ensure its suitability for a particular application. Further, random samples should be analyzed to make sure that its properties can meet the requirement of the operating environment. 

Mortar and ramming mix

The quality of the mortar and ramming mix used in the glass furnace should be similar to the quality and properties of the refractories. AZS ramming mix is used to join the azs brick, while low shrinkage high alumina mortar is used for joining the high alumina blocks. 

Proper dimension

The dimensions of the refractories should be accurate and warpage-free.

Use of anti-corrosion refractory materials 

The the refractories is likely to be damaged due to contact with molten glass and slags. In general, sparking and corrosion are the main causes of the wear and tear of refractories in the glass furnaces. Refractories with good resistance to sparking and corrosion are preferable for the glass melting furnace. Anti-corrosion refractory materials particularly suitable for alkali attack can be considered. The coating should be uniform. 

Right refractory for different parts

Since the operating environment of different parts are different, it is necessary to select the right refractory materials. Silica bricks are preferred in the crown and the azs brick is ideal for the sidewall and tank bottom.

Zhengzhou Sunrise is a refractory material supplier from China, offering high quality refractory materials for glass furnaces, including azs brick, fused cast alumina block, fused cast high zirconia block, mullite brick, zircon brick, alumina bubble brick, magnesia brick, sillimanite brick, corundum brick, low porosity fireclay brick, high alumina brick, all kinds of glass furnace ramming masses, etc..