COMPLEX FERTILIZERS BASED ON LOCAL RAW MATERIALS

Abstract

Phosphorites of the Central Kyzyl Kum are characterized by a high degree of carbonate content, the concentration of CO₂ in some formations reaches 27 % or more. To involve the Kyzylkum phosphorites in the production of concentrated phosphorus-containing fertilizers, ore dressing is required by reducing the proportion of calcite and sesquioxide compounds. One of the effective methods of enrichment of high-carbonate phosphorites can be selective removal of carbonates from the ore by using dilute acids or thermochemical removal of CO₂ with subsequent leaching of free calcium oxide with water or solutions of nitrogen salts. It should be noted that the Kyzyl Kum phosphorites have a high degree of carbonate content, the concentration of CO₂ in some samples reaches 27 % or more. Naturally, with such a high carbonate content in the feedstock, the best way to enrich it is thermal.