Improvements in the manufacture and production of granular mixed fertilisers containing ammonium nitrate, and apparatus therefor

摘要

322,424. Johnson, J. Y., (I. G. Farbenindustrie Akt.-Ges.). Sept. 21, 1928. Divided on 320,708. Manures.-Mixed fertilizers containing ammonium nitrate, but not containing calcium carbonate, in the form of melts are sprayed in fine drops at a temperature of about 15‹ C. to 35‹ C. above the solidification point of the melt, the drops being solidified bv cooling. In one example, diammonium phosphate and ammonium nitrate are mixed in certain proportions and sprayed at 180‹ C., the homogenous melt setting at 92‹ C. In a second example, a fertilizer is obtained containing nitrogen phosphates and potash from potassium chloride, ammonium nitrate, and diammonium phosphate, the first two being mixed at 135‹ C. and the mixture cooled to 105‹ C. for adding the phosphate. The mixture is sprayed at 105‹ C. and sets at 80‹ C. in smooth globular particles of small size. An apparatus is shown in Fig. 1 for mixing and spraying, the materials being mixed in a heated chamber a from which the melt flows into a rotating receptacle c. The receptacle c revolves at a high speed and is provided with apertures d through which the melt is sprayed by centrifugal force. In a modification, the rotating vessel is a curved disc over the edge of which the liquid is thrown by centrifugal force. In another modification, the receptacle c has stationary walls and a rotary bottom between which and the walls is a space for the melt to escape.