Tashkent Chemical-Technological Institute, Tashkent, Uzbekistan

Bobokulova O. S., Associate Professor, oygulsoatovna79@gmail.com

Karshi State Technical University, Karshi, Uzbekistan
Usmanov I. I., Professor, usmanovilham56@gmail.com
Ramazonova D., Master’s Student, dinaramazanova126@gmail.com
Samadiy M. A., Professor, samadiy@inbox.ru

The article presents the results of studies of the process of obtaining liquid nitrogen-calcium fertilizers and fertilizer precipitate by processing phosphate flour – unenriched phosphate raw materials and mineralized mass - waste from enrichment of phosphorites of the Central Kyzylkum with nitric acid followed by neutralization of nitric acid pulp with gaseous ammonia to pH 5–7, separation of liquid and solid phases with obtaining a solution of calcium nitrate and fertilizer precipitate in one technological cycle. Optimum technological parameters of the process are established. Industrial implementation of this technical solution will allow to utilize man-made enrichment waste, involve unenriched phosphate raw materials in industrial production, expand the range and reduce the cost of manufactured products and obtain two types of fertilizer.

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