Ammonized Superphosphate and Liquid Nitrogen-Phosphorus Fertilizer Based on the Decomposition of Washed Dryed Concentrate with a Mixture of Sulfuric and Phosphoric Acids
D. M. Kosimov
Institute General and Inorganic Chemistry of Academy Sciences of the Republic Uzbekistan, Tashkent, Uzbekistan.
A. A. Rasulov
Namangan State University, 160103, Namangan, St. Uychi, 316, Uzbekistan.
Sh. S. Namazov *
Institute General and Inorganic Chemistry of Academy Sciences of the Republic Uzbekistan, Tashkent, Uzbekistan.
A. R. Seitnazarov
Institute General and Inorganic Chemistry of Academy Sciences of the Republic Uzbekistan, Tashkent, Uzbekistan.
B. E. Sultonov
Institute General and Inorganic Chemistry of Academy Sciences of the Republic Uzbekistan, Tashkent, Uzbekistan and Namangan State University, 160103, Namangan, St. Uychi, 316, Uzbekistan.
*Author to whom correspondence should be addressed.
Abstract
The process of obtaining ammoniated superphosphate and liquid NP-fertilizer by phosphorus-sulphuric acid processing of washed and burned phosphorus concentrate (WBPC) in one cycle were studied. It has been established that at ratios of 100 : 5÷10 : 15 the compositions of ammoniated superphosphate samples are characterized as follows (wt., %): Р2О5total(t.). - 20.60-24.85; Р2О5free - absent; Р2О5acceptable by citric acid(ac.c.a.):Р2О5t. = 91.03-100; Р2О5water.solubility(w.s.). : Р2О5t. = 78.87-96.86; N - 4.20-4.79; pH - 2.95-3.17. The product is mainly from calcium sulfate di- and hemihydrate, mono-ammonium phosphate, mono- and dicalcium phosphate, quartz and activated fluorocarbonate apatite. A liquid NP fertilizer consists of 3.22-4.49% N, 16.92-17.75% P2O5, 2.18-2.86% CaO, 0.09-0.19% MgO, 0.5 -0.6% SO3, 0.10-0.11% Fe2O3, 0.003-0.007% Al2O3, while Р2О5ac.c.a.:Р2О5t. = 97.75-100% and Р2О5w.s.: Р2О5t. = 96.93-100%. The material balance of obtaining ammoniated superphosphate and liquid NP-fertilizer in one cycle is calculated. It has been shown that the ammonization of phosphorus-sulfuric acid phosphate pulp results in the maximum precipitation of insoluble components in the form of complex salts, which ensures the production of a purified liquid complex fertilizer for drip irrigation.
Keywords: Ammonia, ammoniated superphosphate, liquid NP-fertilizer, material balance, mixture acids