Norsk Hydro, A.s.

Norskhydro Asa

Yara International Asa

Jan Birger Isaksen

Torstein Obrestad

Lars Gustav Moland

Oyvind Skauli

Bj0rn Juliussen

Lars Moland

Leif G Helleb0

The invention concerns a method for the production of nitrate containing products (fertilizers, technical products) from undercooling melts, wherein a XN&#x2014;water solution is evaporated up to a content of 50-99.8 weight % XN, where X is one or more selected from Ca, Mg, NH, Na and K, and N means nitrate. The preferred range of XN is 70-99.5 weight %. The melt is cooled down to and kept at a temperature at or below the crystallisation point and finely divided solid XN powder consisting of the equilibrium phases is added to the melt. Melt drops are then formed and allowed to cool and solidify during up to 70 seconds. It is preferred to use a cooling belt for solidification of the particles. The belt is cooled by air, water, oil or another medium.

Method for production of nitrate-containing products from undercooling melts

The invention relates to a method for making NK-fertilizers basically from calcium nitrate fertilizers and potassium nitrate and homogeneous NK-fertilizer products. Calcium nitrate fertilizer is melted together with potassium nitrate to form a melt or suspension thereof which is particulated to form a homogeneous NK-fertilizer. The calcium nitrate fertilizer and the potassium nitrate are melted at 90-120&deg; C. and then heated to the desired particulation temperature being 160-190&deg; C. for prilling and 90-140&deg; C. for granulation. The components are mixed in ratios giving a melt or suspension comprising 40-14 weight % calcium nitrate, 55-85 weight % potassium nitrate, 0.5-6 weight % water, 0-4 weight % ammonium nitrate and 0-5 weight % magnesium nitrate.

Method for making nitrogen-potassium fertilizer containing calcium nitrate and products thereof

Method of manufacturing free-flowing ammonium nitrate particles applying

Animal feed grade phosphates such as mono-calcium phosphate, di-calcium phosphate or mixtures thereof are produced by direct reaction between phosphoric acid and Ca-containing materials. A finely ground, preheated calcium carbonate suspension is brought to react with a suitable quantity of preheated phosphoric acid by introducing the reactants into a short, tubular reaction zone, open at one end, whereby development of gas and intensive mixing of the reactants in the reaction zone take place. The gas formed by the reaction expels or ejects the foaming reaction mixture from the tube-like reaction zone, the reaction being substantially completed while the individual particles of the mixture are freely suspended in air or gas, whereafter the reacted mixture is collected in the form of a free-flowing granulate having improved handling properties, without any further quenching treatment of the granules. An apparatus for carrying out the process includes a reaction chamber connected with separate feed lines for calcium carbonate suspension and phosphoric acid, respectively, and means for collecting and further processing the resultant reaction product. The reaction chamber has the form of a tube reactor having an open end portion which forms a discharge which is arranged for cooperation with a suspension chamber and a collecting device arranged at the lower end of the chamber.

Method for producing calcium phosphates

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Porsgrunn, Norway

Jan Birger Isaksen