Patent ID: 6740299
Filing Date: 2004-05-25
Classification: C04B

Abstract:
A method of manufacturing a phosphate-bonded refractory product entirely during the mixing cycle by reacting phosphoric acid and alumina derived from a source of finely divided reactive alumina comprising &bgr;-alumina to form a proto aluminum orthophosphate gel or paste binder in the pan of a high-intensity mixer at ambient temperatures comprising the steps of:a) proportioning ingredients of a size-graded refractory composition including a source of finely divided reactive alumina comprising &bgr;-alumina; b) blending the ingredients to distribute the finely divided reactive alumina source uniformly through the batch; c) adding up to one half of the required water; d) adding 75 or 85 percent phosphoric acid to the mix in an amount to provide an atomic ratio of aluminum, derived from a source of finely divided reactive alumina, to the phosphorus, derived from the phosphoric acid, of about 1:1 such that the source of finely divided reactive alumina and phosphoric acid react in the pan of the high-intensity mixer; and e) adding the balance of the required water to obtain the desired workability.