How to evaluate the density of refractory brick

With the continuous development of China’s cement industry; higher requirements for fire resistant materials are also put forward. Long term dependence on the extensive economic growth mode of the refractory industry, should be increased to adjust the intensity of the need to adapt to the new situation, then in the purchase, we should be how to determine the density of fire bricks, and hope that the following text will help.

Refractory brick is a rich in hydrous aluminum silicate siliceous clay and has the capability of high temperature deformation, not broken, do not soften and not paste, refractory bricks in the amorphous material department, there are a variety of consumer products, the basic quality requirements of alumina is higher than 38% and low iron and low content of alkali metal. These products can be claimed or calcined, such as refractory clay, overloaded with plastic material, high alumina plastics, fireclay and high alumina pouring material and the other. Different quality mud with different appliances, cement with clean water, accurate weighing modulation, uniform mixing.

If is already a good tune mud, it shall not be arbitrarily diluted with water and mortar plumpness to greater than 95% above to ensure dense refractory brickjoints, surface brick joints to puree pointing, housing cannot correct position with mud is looking. Bricks with a certain shape and size, weight per unit volume, density, that good compactness and strength is likely to be, also called high temperature load to deformation temperature, called heavy firing line changes or called residual line change, refers to each in the same temperature changes in volume expansion and contraction of the change, high temperature resistant, about 1800 degrees, refractoriness under load in 1620-1640, low coefficient of thermal expansion.

How to choose the different parts of the refractory lining of blast furnace

In the process of production and in the selection of various parts of the refractory lining, should follow the principle is: the refractory lining to correspond to the parts of the heat flow intensity, to keep under the impact of strong heat and lining can still maintain the continuity and stability of the cone. Each part of the refractory brick selection method is:

(1) Furnace throat. The main burden to withstand the impact and abrasion, generally used steel brick or water cooling steel brick.

(2) The upper shaft. Analysis of reaction of carbon 2CO2-CO + C easy happening areas is the site and alkali metal, zinc vapor erosion also occurred in this area. Plus the burden descent and ascending gas flow of scour and wear. Therefore, we should choose resistance to chemical erosion and abrasion resistance of refractory materials, the most appropriate is high relative density brick, high density, high aluminum brick or phosphoric acid impregnated clay brick.

(3) And lower body in the belly. The main mechanism of damage is thermal shock, high temperature gas scouring, alkali metals, zinc and carbon deposition, and chemical erosion of the initial slag. Should the lining refractory material thermal shock, resistance to slag erosion and erosion protection.

1000m3 and the following blast furnace can be used for aluminum carbon brick.

(4) Bosh. Hot gas erosion and iron slag erosion is the main reasons for the damage, this part of the heat flux intensity, refractory material life not long (as long as 1-2 months short 2-3 weeks), generally used in refractory degree is high, load softening temperature is high and the volume density of refractory material, such as the high aluminum brick, alumina carbon brick.

(5) Hearth tuber. This site is only in blast furnace of oxidation reaction area, high temperature up to 1900~2400 DEG C, lining by damage caused by high temperature thermal stress. Composite brick masonry hearth tuyere zone is adopted by the modern blast furnace, material for high alumina, corundum Mo mullite; corundum and silicon nitride combined silicon carbide, useful also hot pressed carbon block.

(6) The lower part of the hearth and bottom. The high thermal conductivity, resistance to penetration of high, resistance to chemical attack high, porosity, micro aperture of hot pressing small carbon bricks, micro porous carbon brick, hot semi graphite carbon brick and ceramic cup brown corundum or gray corundum brick etc. by this part of the refractory material. Taphole area work condition is bad, now the hearth refractory material matched with iron composite brick masonry, used in the production of carbonaceous, semi graphite G-Sic, Mo mullite, SiC material.