The aim is to readapt the current fertilizer production process in QSr (currently producing KNO3, Ca(NO3)2, Mg(NO3)2, Sr(NO3)2, SrCO3, (NH4)2SO4 and NH4NO3) to replace imported raw material (HCl and CaCO3), utilise CO2 from surrounding industries and reduce waste water discharge and water consumption.
Currently, fertilizers and strontium derivates are produced in parallel processes in the same facility in QSr. First, the strontium mineral is leached with HCl to purify SrSO4.
As a result of the leaching process, wastewater with high concentration of CaCl2 is produced, which reacts with the sulphates discharged upstream, generating CaSO4 which causes severe plugs in the pipeline infrastructure.
This SrSO4 is fed into a set of carbonation reactors working with NH3 and CO2 imported from a nearby industry (“Ecocarburantes Españoles”) to produce SrCO3, obtaining (NH4)2SO4 and NH4NO3 as by-products. Additionally, KNO3 is produced by reacting NH4NO3 and KCl.
NH4Cl is obtained as a by-product, which has little market demand. In parallel, Ca(NO3)2 is obtained by direct reaction of HNO3 and CaCO3, emitting CO2 in the process.