METHOD FOR STUDYING COMPOSITION OF NITROGEN-CONTAINING FERTILIZER BASED ON CARBAMIDE AND AMMONIUM NITRATE Russian patent published in 1998 - IPC

FIELD: agriculture. SUBSTANCE: method involves determining density of mixed aqueous solution of carbamide and ammonium nitrate at 25 C and determining ammonium nitrate concentration in the same solution using titrimetric method. Then solution composition index like total mass share of nitrogen is calculated from an equation with constant coefficients. Other ingredients like ammonium phosphate as corrosion inhibitor (0.2% P₂O₅) or microelements (from several hundredth fractions of percent to several percents) are added in relatively small amounts to mixed aqueous solution of carbamide and ammonium nitrate used as liquid nitrogen-containing fertilizers in agriculture depending on purposes pursued. The method takes into consideration influence of concomitant admixtures upon the density of the mixed aqueous solution of carbamide and ammonium nitrate and contributes in this way to reducing complicated problem of liquid nitrogen-containing fertilizers composition analysis under conditions of various admixtures present, to more simple already solved problem of analysis of pure mixed aqueous solution of carbamide and ammonium nitrate. In this case, the fertilizer to be analyzed is set in correspondence to mixed aqueous solution of carbamide and ammonium nitrate that could be obtained from the fertilizer if the concomitant admixture substances present in the latter had been substituted for quantities of water being equivalent to them by mass. Density of pure mixed aqueous solution of carbamide and ammonium nitrate obtained in this way can be easily calculated depending on admixture contents in the fertilizer and on temperature at which fertilizer density is measured in the interval from 20 to 30 C. Not only total nitrogen share but also mass share of carbamide in the fertilizer having concomitant admixture substances can be calculated as a result of applying the method. EFFECT: enhanced accuracy of method; simplified calculations. 3 cl, 3 dwg