METHOD OF PRODUCING HIGH-CONDENSED AMMONIUM PHOSPHATE OF CHAIN STRUCTURE Russian patent published in 1998 - IPC

FIELD: refractory materials. SUBSTANCE: method involves heating a mixture containing urea and ammonium ortho-phosphate at their ratio = (1-1.2):1, respectively, at 270-300 C in the presence of ammonium polyphosphate followed by product grinding. A mixture of ammonium ortho-phosphate and urea is fed at the rate 95-195 kg/h on ammonium polyphosphate layer of height 0.25-1 m (granule size is 3 mm, not above). The produced ammonium polyphosphate is used as a component of refractory coatings and refractory structural materials. EFFECT: improved method of producing. 2 tbl