Screening machine for super-phosphate, San Juan de Nieva
Meike Schulz, RHEWUM GmbH
Already in March 2011 RHEWUM supplied a screening machine type RHEWUM WAU to the Spanish fertilizer producer Asturiana de Fertlizantes S.A.
The screening machine operates up to 1.900 tons per day of super-phosphate, it separates the fertilizer at 6,0 mm and 2,0 mm. The screen cut of 6,0 mm keeps agglomerates out of the product stream reliably whereas at the same time the screening at 2,0 mm ensures the de-dusting of the ready for sale super-phosphate. (SP) which simplify the distribution on the field in order to equalize the nutrition of the plants.
Super-phosphate (SP) Super-phosphate is produced by decomposing of natural rock phosphate with sulphuric acid. In this process water-insoluble calcium sulphate as well as calcium hydrogen phosphate is formed. This mixture already contains approx. 20% of super-phosphate (P2O5). This process was developed by the Briton John Bennet Laws (1814-1900). Besides super-phosphates used as fertilizer double super-phosphate (DSP) and triple super-phosphate (TSP) are used as fertilizer as will. The phosphate content increases up to approx. 36% for DSP and 48% for TSP.
Asturiana de Fertilizantes S.A. produces as joint venture besides fertilizers chemicals as magnesium super-phosphate and sulfate. The production site is located at San Juan de Nieva in the North of Spain, easily to access at the Atlantic Ocean.