Abstract: A process is described for a water efficient, ecologically acceptable collection, delivery and depositing of slag and flyash from thermal power plants fired with pulverized coal. Slag is allowed to fall into a cooling water basin, conveyed to a condenser where it is combined with coarse flyash, te slag-flyash combination is delivered to a mixing space and combined with fine flyash, thereby forming a homogeneous mixture and the mixture is then circulated under specified conditions to achieve comminution to a predetermine value. Comminuted homogeneous mixtures is then measured continuously for properties of viscosity, quantity and pressure parameters. Information on the parameters is fed to a computer for comparison with preset values. The comminuted homogeneous mixture is then deposited in a deposit space. Any cooling water lost in the collecting-delivering and depositing steps is then replaced. A colloidal material may be added to the comminuted homogeneous mixture during the deposition step.

Abstract: A qualification method which enables a fast, exact and numerical determination of puzzoulana-properties of solid materials and thus a short evaluation of said solid materials from the point of view of industrial usability.According to this method the puzzoulana-properties and activity of solid materials can be defined by a single figure as a result of their chemical and physical properties. The material to be analyzed is brought together with fluoride ions in an acidic medium in a system having constant heat capacity and the change of the heat quantity is measured and evaluated in the initial, suitable linear, phase of the resulting reaction. The time function of the change of the heat quantity of the system is converted into a change of voltage and the rise of this curve is determined advantageously in the linear section. Advantageously the change of the heat quantity of the system is measured within less than 30 seconds, favorably at about the 20th second.

Abstract: A low grade aluminum and silicon containing starting material is intimately mixed with limestone and the resultant mixture is fluidized. The fluidized mixture is preheated to a temperature of 700.degree. to 900.degree. C., then held at sintering temperature for 5 to 10 minutes. Aluminum may be recovered by extraction of the sintered powder so produced.