Potassium mixture, ammoniated

During manufacture of 26/16/10 N/P/K fertiliser by ammoniation of nitric-phosphoric acid mixtures, followed by concentration, addition of potassium sulfate, then granulation at up to 250°C, the possibility of a thermal explosion exists. Kinetic studies showed that 240°C appears to be a safe granulation temperature, but that changes in the composition and pH of the mixture may decrease this critical temperature. 

Hand grinding of a mixture of ammoni-um sulfate, ammonium bisulfate, sodium chloride, potassium bicarbonate, and talc in dry nitrogen produces a dust that can readily be dispersed onto test substrates. The resulting particles are typically 1-5 pm in diameter. A typical composition is shown in Table 9-5. The composition of the dust can be adjusted to match the electrical leakage properties on circuit boards of fine-particle dust found in field locations. Two methods of dispersion were found to be effective ... 

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