Factors Affecting Manufacturing of Single Superphosphate

摘要

Single Superphosphate(SSP)is produced by acidulation of rock phosphate with sulphuric acid.The phosphate rock contains many impurities including calcium carbonate,magnesium carbonate,iron trioxide,aluminium oxide and calcium fluoride,etc.these impurities affect the reaction consumption of raw materials and quality of product.As the content of each impurity component increases,the effective P2O5 content and free acid P2O5 content of superphosphate products decrease,the free water content increases,the phosphate rock consumption quota decreases,and the sulphuric acid consumption quota increases.Among them,Al2O3 has the greatest impact on the product's effective P2O5 and free water content,CaF2 has the greatest impact on the product's free acid P2O5 content and phosphate rock consumption quota,and MgCO3 has the greatest impact on the sulphuric acid consumption.The cumulative effect of various impurities on production indicators has a superimposing effect.In SSP process,acid/rock ratio and percentage of sulphuric acid are in the range of 1.61-2.06 and 65%-75% respectively depending upon rock phosphate quality.The paper gives the details,effect of various impurities in rock phosphate and other process parameters on quality of product.Considerations in scrubbing of fluorine from emissions are also included.