Abstract: The present disclosure discloses a method, product, and system for cogenerating ferric phosphate through a nitrophosphate fertilizer device. The method comprises the steps of: acid-hydrolyzing phosphate rock with a nitric acid, and separating acid-insoluble substances to obtain an acid-hydrolyzed solution; freezing-crystallizing the acid-hydrolyzed solution, and carrying out solid-liquid separation to obtain a first solution; adding a solution containing sulfate ions to the first solution for reaction to obtain a second solution; subjecting the second solution to a denitrification to obtain a third solution; adding ammonia to the third solution for neutralization, and carrying out solid-liquid separation to obtain an ammonium phosphate solution, and adding an iron source to the ammonium phosphate solution for reaction to prepare a ferric phosphate.

Abstract: Disclosed is a method for preparing iron phosphate and by-product fertilizer using ammonium phosphate. The granulation device for by-product fertilizer production comprises a housing having accommodation space which is divided from top to bottom into a granulation chamber, a material-screening chamber and a temporary material-storing chamber; a blowing component provided between the granulation chamber and the material-screening chamber; and a vibrating screen which is able to vertically reciprocated provided between the material-screening chamber and the temporary material-storing chamber which is connected to a discharge pipe, wherein the upper end of the housing is provided with a detachable cover having multiple spraying devices for spraying the molten material into the housing and connected to an exhaust pipe.