The role of aluminum powder in the production of aerated concrete



Most manufacturers of aerated concrete, both autoclaved and non-autoclaved, use aluminum powder as a blowing agent. This is mainly due to its low price in comparison with aluminum paste and hydrophilic powder. In addition, formulations have been developed at production sites that ensure stable characteristics of the finished product. Compliance with the alumininium paste and powder Malaysia rules of personal hygiene and the use of aluminum powder allows to make production safe. 

If improperly used, aluminum powders are very dusty and form an air suspension in the air. This can be avoided by ensuring a tightness during pouring and good ventilation in the room. Also, aluminum powders are not wetted with water (hydrophobic). This is due to the fact that the surface of the flakes contains a fatty additive that is used in production and ensures the preservation of the properties of the powder. If you try to mix the powder with water, then some of the powder will mix with water (no more than 20%), but the main part will be on the surface of the water. Its use in this form in the production of aerated concrete is impossible – al. the suspension is heterogeneous, it will not work to distribute the aluminum flakes over the array, ensuring its uniform rise.  

To make aluminum powder hydrophilic and to obtain a homogeneous suspension, various additives are used – washing powder, sulfanol, hydrophilic additives. All of them act as follows – under the influence of water and active substances, they wash off the stearic membrane from the scales, the scales without stearin are drawn into the water. Aluminum flakes have a high specific surface area, which ensures their uniform distribution in water for a long time (up to 20 minutes, the flakes completely settle to the bottom after 2-3 hours). 

Preparation of a mixture and lifting of aerated concrete using this additive is no different from preparation based on aluminum paste – both domestic and imported. At the same time, it is much more economically profitable. Additive consumption – 1-4% by weight of aluminum, depending on the brand. Preparation of a mixture and lifting of aerated concrete using this additive is no different from preparation based on aluminum paste – both domestic and imported. At the same time, it is much more economically profitable. For more articles like this one, click here.