PHYSICO-CHEMICAL STUDIES OF RAW MATERIALS FOR OBTAINING PHOSPHORUS-CONTAINING FERTILIZERS

To date, accumulated industrial waste creates serious environmental problems in the regions. Therefore, their processing in order to obtain valuable products is an urgent task. As a result of the reduction electric smelting of phosphorite raw materials in the Novo-Dzhambul phosphorus plant, about 150-160 kg of cuttrel dust is formed per 1 ton of yellow phosphorus. The resulting cuttrel dust is considered as a secondary raw material, it can be used to obtain phosphoruscontaining mineral fertilizers, since the boiler dust contains a proportion of phosphorus and other useful components. The purpose of this work is the processing of phosphorus production waste - cuttrel dust with the use of sulfuric acid to obtain phosphorus-containing mineral fertilizers. Methodology. For the processing of cuttrel dust under experimental conditions, instrumental test methods were chosen using a scanning electron microscope (SEM) of the Jeol JSM-6490l V brand, a multi-parameter portable cyberscanner (PCD 650 Eutech) and a Q-1500 Derivatograph. Results. According to the results of microscopic studies, it was determined that the content of the main useful component in the cuttrel dust P2O5 in the range of 30-31%. The thermodynamic regularities of the process of decomposition of cuttrel dust with the help of a solution of sulfuric acid have been studied. The standard thermal effects of changes in the enthalpy, entropy and the value of the Gibbs energy of the system at a temperature of 333–363K were determined using the HSC-6 complex program. The methods of mathematical processing are considered in order to determine the reliability of the results of the experimental work. The optimal technological parameters of this process have been established and determined. Conclusion. A technology has been developed for obtaining phosphorus-containing monocalcium phosphate based cuttrel dust from the waste of the Novo-Dzhambul phosphorus plant using sulfuric acid solutions. The advantage of the resulting phosphorus-containing component is that it has a high solubility and absorption of phosphorus to plants. They are also characterized by a high content of phosphorus-containing substances, which ensure the growth and productivity of agricultural plants and plant resistance to environmental stress factors.