TECHNOLOGY FOR PRODUCING THERMOPHOSPHATE PRODUCTS BASED ON PHOSPHORITES WITH ADDITIVES OF ALKALINE SALTS

Abstract

The essence of this work is to study the microstructure and mechanical properties of mixed salts of alkali metals, such as sodium and potassium, phosphorites of the Central Kyzylkum of various compositions. This raw material, low in phosphorus and rich in carbonate and chlorine, is not suitable for acid treatment. To obtain high-quality phosphate fertilizers from raw materials, it must first be enriched. At the Kyzylkum Phosphate Plant, multi-stage enrichment is carried out: crushing, dry enrichment, chlorine removal, sintering to remove CO2. One of the promising areas for the processing of phosphate raw materials of this type is heat treatment, based on the destruction of the crystalline structure of the mineral, which is indigestible by plants, during thermal activation. The work is aimed at obtaining a thermophosphate fertilizer, which is insoluble in water at different temperatures and times in optimal proportions with sodium chloride, sulfate, potassium carbonate, chloride, sulfate salts, sylvinite and silicon oxide/coal, which are more active. The regularity of the influence of temperature and weight ratios of the mineralized mass from the fractions of phosphorite ore of the Central Kyzylkum: silicon oxide/coal: sodium salts on the assimilable phosphorus in thermophosphate fertilizer is shown, as well as the fact that the digestibility of phosphorite ore of the II-layer is higher than that of other raw materials. An increase in the content of assimilable phosphorus in synthesized primary phosphorus thermophosphate fertilizers with an increase in temperature and time is substantiated at equal weight ratios of phosphorite ore of the II layer: silicon oxide/coal: sodium salt.