Aluminum powder use for light weight concrete block
Uses of aluminum powder with gasification
The main application of aerated aluminum powder for aerated concrete is to undergo a chemical reaction with silica and lime in the production process, releasing gas and creating a porous structure within the produced concrete blocks. In the batching process of aerated concrete block production, the aerated material is added to the aluminum powder slurry mixing tank, then thoroughly mixed and placed in the aluminum powder slurry metering scale, and finally combined with lime, gypsum, fly ash and other raw materials into the pouring mixer. The aluminum powder in the aerated concrete slurry can react with alkaline substances to release hydrogen gas, creating bubbles and causing the aerated concrete slurry to expand and form a porous structure. This results in the produced aerated concrete blocks having a general weight of 500-700 kg/m³, which is only 1/4 to 1/5 of clay bricks and 1/5 of ordinary concrete, making it a relatively lightweight type of concrete. Compared to ordinary brick and concrete structures, the self-weight is reduced by more than 40%.
Requirements for aerated aluminum powder
Aerated aluminum powder is the gas-forming material used in aerated concrete. In 1923, the Swede Eriksson mastered the production technology using aluminum powder as a gas-forming agent and obtained a patent. Aluminum powder has a large gas production capacity, produces hydrogen gas with a small solubility in water, has high gas-forming efficiency, is easy to control during the gas-forming process, and has a wide source, providing conditions for large-scale industrial production. Currently, the aerated concrete industry in China usually uses aerated aluminum powder paste, using pure aluminum foil as the raw material, adding media and various additives and grinding finely in a ball mill to obtain an aluminum slurry, which is then centrifugally concentrated into a paste-like form. The production process of aerated concrete requires that the gas-forming of aluminum powder must match the thickening and hardening of the slurry, which imposes certain requirements on the quality of aerated aluminum powder.
