The benefits of two-component concretes, in which, in addition to refractory aggregate, the second component is an orthophosphoric acid based chemical binder over traditional hydraulic hardening concretes is a shorter time for putting the lining into operation. In turn, these two-component concretes have a number of significant drawbacks, the main of which are the phosphoric acid and its water-soluble salts effect on the human body, as well as on the environment both in the process of working with these components and in the process of disposal of containers, in which this acid is supplied alongside with the refractory aggregate.
Another drawback which the consumer should consider is the presence of titanium and silicon oxides in the composition. In the process of the long-term contact with liquid aluminum, these two filler components are reduced to metal, followed by secondary oxidation, resulting in the working layer of the lining destruction and an increase in the content of harmful non-metallic inclusions in the aluminum melt.
In addition, the mode of drying and heating concrete on a chemical binder requires proper adherence to the approved schedule of heat treatment and, in fact, averages no more than 70 degrees per hour.
We have developed a special type of refractory concrete that is resistant both to melts of non-ferrous and ferrous metals, and to liquid slags formed in the process of metal production. This concrete has all the positive qualities of both a chemical binder based two-component concretes and a hydraulic binder based concretes. The operating temperature of such concrete is in a very wide range: from 300 to 1900°C.
The setting time of concrete is regulated from 20 minutes to 1.5 hours at the customer request. The minimum time for formwork removing is 5 hours. The average lining heating rate before putting it into operation is 100°C.
This concrete has a unique thermal stability and withstands more than 50 water thermal cycles 1300°C – water.
The absence of silicon oxide and low-melting compounds in the composition ensures the liquid phase appearance only at temperatures above 1700°C.
During the formation of the concrete structure during operation, diffusion sintering predominates, which ensures high mechanical strength at both low and high temperatures.
The shelf life of this concrete is up to 12 months and it can be supplied in any agreed with the customers container.