The distinguishing feature of the proposed flow method before the classical (chamber) method is that the entire production cycle of natural phosphate processing is carried out in two stages. At the first stage, the phosphorite is treated with a stoichiometric flow rate of concentrated sulphuric acid (at least 93%), under conditions of complete decomposition of phosphorite to form phosphoric acid and crystals of anhydrite (calcium sulfate). The reaction temperature is 122 °C. In the second stage, the resulting concentrated solution of phosphoric acid in a mixture with sulphur is involved in a reaction with an additional input of phosphorite, which is the basis for the mechanism of chemical formation of monocalciumphosphate and granulation of superphosphate mass. The processes for neutralizing phosphoric acid on monocalciumphosphate and for granulating the product by coagulation are combined in one apparatus. The drying stage of the product is excluded from the scheme.

This article presents the results of research on the production of fertilizers using water-saving hydrogel on the basis of local raw materials. The reaction of ParPAN raw materials with inorganic and organic acids and in the presence of formalin has been studied. According to the results of research, a new type of hydrogel was synthesized. The degree of swelling of the hydrogel has been found to be related to the amount of formalin and other additives. The composition of the hydrogel composition with mineral fertilizer was developed, its basic physico-chemical characteristics and swelling kinetics were studied. The use of hydrogels as a means of keeping moisture and feed components in arid and low-water agricultural regions of the Republic of Uzbekistan is recommended.

No abstract

The results of many years of research on the effect of polymer hydrogels for agriculture on soil structure were presented. By sampling soils at various depths, the biological changes of microorganisms that occur under the influence of hydrogels were studied. It was shown that the use of hydrogels leads to an improvement in the basic physicochemical properties of non-irrigated agricultural lands and an increase in soil fertility. The use of hydrogel absorbent on typical non-irrigated lands allowed increasing soil moisture and improving its properties.

No abstract