Abstract
Phosphorous-acid process of Karatau phosphorites’ decomposition has been studied. The impact of temperature, time and acid rate on decomposition process of phosphate raw material, the conditions ensuring maximum degree of phosphorite decomposition have been identified. Variance estimate of experiment results’ reproducibility has been carried out by mathematical statistics method; the coefficients of regression equations have been set. The significance of regression equation coefficients has been checked up by Student’s criterion, and the adequacy of regression equation to experiment has been checked up by Fisher's criterion. With the use of utopian point method the parameters of studied rawmaterials’ decomposition have been optimized.