Production of suspension fertilizers from orthophorphoric acid
AssigneeTennessee Valley Authority
InventorsThomas M. Jones, John M. Stinson
Life of this patent
Estimating the term…
Abstract
An improved process for the production of concentrated, high-grade, nitrogen-phosphate (N--P.sub.2 O.sub.5) base suspension fertilizer from wet-process or other phosphoric acids and ammonia. The process involves addition of small proportions of fluosilicic acid during preparation of the suspension to cause modification of monoammonium phosphate crystals to shapes and sizes that do not settle during vibration such as occurs during shipment.
Claims4
A process for the production of suspension-type fertilizers from wet-process phosphoric acid and ammonia, which suspensions have high plant food contents, excellent flow properties, low viscosities, good storage properties, and do not contain settled crystals after exposure to substantial vibration, which process comprises the steps of:
- (1) simultaneously adding in predetermined proportions a stream of ammonia, of water, and of wet-process phosphoric acid to a first-stage reactor to effect a partially ammoniated feed phosphoric acid material therein having a N:P.sub.2 O.sub.5 weight ratio ranging from about 0.15 to about 0.28;
- (2) removing at least a portion of the resulting partially ammoniated acid from said first-stage reactor and introducing same into a second-stage reactor, together with a stream of additional ammonia in predetermined proportions to effect an ammoniated phosphoric acid material therein having a N:P.sub.2 O.sub.5 weight ratio ranging between about 0.26 to about 0.34;
- (3) removing at least a portion of said ammoniated material from said second-stage reactor and subsequently introducing same into cooling means wherein said ammoniated material is cooled to a temperature in the range from about 80.degree. F. to about 150.degree. F.;
- (4) subsequently removing the resulting ammoniated material from said cooling means and introducing same, at a temperature in the range from about 80.degree. F. to about 150.degree. F., to a mixing vessel, together with from about 0.5 percent to about 2 percent by weight clay and from about 0.1 percent to about 0.5 percent by weight fluosilicic acid, said fluosilicic acid based on the weight of the resulting stable suspension;
- and
- (5) removing the resultant stable suspension from said mixing vessel to storage.
Dependencies are inferred from the claim text.