Agglomeration of powdered tripolyphosphates

Claim 1

A PROCESS FOR AGGLOMERATING ALKALI METAL TRIPOLYPHOSPHATE WHICH COMPRISES (A) HEATING A MIXTURE OF FINELY DIVIDED ALKALI METAL TRIPOLYPHOSPHATE WITH A BLEND OF FINELY DIVIDED ALKALI METAL ORTHOPHOSPHATE SALTS, WHERE THE OVERALL MOLAR RATIO OF ALKALI METAL OXIDE TO P2O5 OF SAID BLEND OF FINELY DIVIDED ALKALI METAL ORTHOPHOSPHATE SALTS IS GREATER THAN ABOUT 1.5 AND LESS THAN 2.0 AND SAID BLEND OF FINELY DIVIDED ALKALI METAL ORTHOPHOSPHATE SALTS REPRESENTS BETWEEN ABOUT 10% AND ABOUT 75% BY WEIGHT, OF THE TOTAL WEIGHT OF THE COMBINED ORTHOPHOSPHATES AND TRIPOLYPHOSPHATE, SAID HEATING BEING CONDUCTED WHILE SAID MIXTURE IS BEING AGITATED AT A TEMPERATURE WHICH IS SUFFICIENTLY HIGH TO EFFECT THE CONVERSION OF ALKALI METAL ORTHOPHOSPHATES TO ALKALI METAL TRIPOLYPHOSPHATE, BUT BELOW THE MELTING POINT OF THE ALKALI METAL TRIPOLYPHOSPHATE, TO THEREBY PRODUCE A PARTICULATED AGGLOMERATED FORM OF THE ALKALI METAL TRIPOLYPHOSPHATE, AND (B) SEPARATING THE RESULTING CALCINED MATERIAL INTO A PLURALITY OF FRACTIONS BASED ON THE PARTICLES SIZE DISTRIBUTION OF SAID CALCINE MATERIAL, AT LEAST OF SAID FRACTIONS CONSISTING OF RELATIVELY SMALL PARTICLES AND AT LEAST ONE OF SAID FRACTIONS CONSISTING OF RELATIVELY LARGER PARTICLES, AS COMPARED WITH SAID RELATIVELY SMALL PARTICLES.