Classification of new wholesale process of magnesia brick

Light burned powder is a kind of alkaline oxide with high activity obtained magnesite by light burning at a certain temperature. 97 fused magnesia is usually processed into 100-325 mesh fine powder for sale. The price of concentrate powder is that the main component of magnesia chrome brick is magnesium oxide, which often contains oxide impurities such as iron, manganese, aluminum, calcium, silicon, etc., commonly known as "light burned magnesium". The economic benefit can be greatly improved by deep-processing of superfine magnesia. The basic magnesium carbonate precursor was obtained by adding precipitant. The purity of magnesium oxide was 98.3% after calcination decomposition. This method has the advantages of short technological process, simple operation, less investment, easy to obtain raw materials, low product cost good economic benefit. The raw materials used in the production of magnesia chrome brick include natural raw materials, synthetic raw materials, industrial chromium oxide industrial alumina. Natural raw materials: such as various grades of sintered magnesia, ordinary chrome ore chrome concentrate with low impurity content. Synthetic raw materials: CO sintered magnesia chrome material made magnesia chrome concentrate by fine grinding, mixing, pressing, then calcining at high temperature; fused magnesia chrome material made magnesite chrome ore by electric melting; fused magnesia. Generally, the synthetic material should be the raw material with low impurity content. Magnesia chrome bricks with various names can be made by using different combinations formulas of the above raw materials. In addition, the manufacturer is unwilling to explain the formula more, so the varieties names of magnesia chrome bricks are very confusing. According to the existing names of magnesia chrome brick at home abroad, it can be roughly standardized as follows.

Price of concentrate powder

(1) Ordinary magnesia chrome brick

The brick is made of chromite magnesite with more impurities (SiO2 Cao). The sintering temperature is high, about 1550 ℃. The microstructure of the brick is characterized by the combination of silicate between the refractory grains. The fine powder of this kind of refractory brick is the magnesia chrome material ground, mixed, pressed calcined by ordinary chrome ore magnesia, which is still silicate bonded. However, the properties of magnesia brick are better than that of ordinary magnesia brick.

(2) Direct bonded magnesia brick

It is made of chrome concentrate with low impurity content pure magnesia. The firing temperature is above 1700 ℃. The structural feature of the refractory brick is that the grains of the refractory are in direct contact with each other. Therefore, its high temperature performance, corrosion resistance erosion resistance are better than ordinary magnesia chrome brick.

(3) Re bonded magnesia chrome brick

In foreign countries, the magnesia chrome bricks made entirely synthetic raw materials co sintered magnesia chrome fused magnesia chrome ( partly fused magnesia) are called re bonded magnesia chrome bricks. However, in China, only the magnesia chrome bricks made of all fused magnesia chrome materials are called re bonded magnesia chrome bricks. In order to be more consistent with the international standards, it is appropriate to use CO fired magnesia chrome brick fused material combined with magnesia chrome brick fused grain combined magnesia chrome brick. Combined with magnesia chrome brick, because the raw material is pure, it needs to be fired at high temperature above 1750 ℃ ultra-high temperature. The microstructure is characterized by uniform distribution of spinel other components direct contact between refractory grains. It is better than the former two kinds of magnesia chrome bricks in erosion resistance erosion resistance. The high quality magnesia chrome bricks we developed for the tuyere of Nickel Converter also belong to this kind of refractory bricks because the raw materials used are all synthetic materials.

(4) Semi re bonded magnesia chrome brick

According to the above meaning of combined magnesia chrome brick, as long as the synthetic raw materials are used as particles, the magnesia chrome brick made of chrome concentrate magnesia as fine powder should be called semi combined magnesia chrome brick. In China, the semi reconstituted magnesia chrome brick is made of fused magnesia chrome material as particles, the fine powder is made of CO agglomerated material the mixed fine powder of chrome concentrate powder magnesia powder. In order to distinguish, the magnesia chrome brick made of fused materials as particles co sintered magnesia chrome materials as fine powder can be called fused particles co sintered magnesia chrome brick. This kind of refractory brick is also fired at a high temperature above 1700 ℃, the direct bonding between the refractory grains in the brick is also dominant. Its advantages are good thermal shock resistance, erosion resistance erosion resistance.

(5) Fused cast magnesia chrome brick

Magnesia chromite are mixed with a certain amount of additive, pressed burned, broken into blocks, melted in electric arc furnace, injected into mold annealed to produce mother brick. The mother brick is cut grinded to produce the required type of refractory brick. The structural characteristics of the fused cast magnesia chrome brick are that the components are evenly distributed, the grains of the refractory are mainly in direct contact, the silicate exists as islands. The refractory brick has excellent resistance to melt erosion, penetration erosion. It is a product specially developed for nonferrous smelting. It is suitable to be built in smelting furnace of continuous production equipment, such as the lower part of reaction tower of flash furnace slag line area of sedimentation tank.

(6) Chemically bonded unfired magnesia chrome brick

Generally, magnesia chromite are used as raw materials for brick making, sodium polyphosphate sodium hexametaphosphate sodium silicate are used as binder for pressing magnesia chrome brick. No need to burn at high temperature, only bake at about 200 ℃. Because the refractory brick is fired at high temperature, the magnesia in the brick will hydration, so the refractory brick can be stored for a long time. Chrome ore can be used as raw material for unburned brick because of its small shrinkage when used at high temperature.