Phosphoric Acid — Feedstock for Fertilizers & Food Phosphates
Wet-process phosphoric acid at 75–85% concentration feeds MAP, DAP and TSP granulation plants, purified food-grade phosphate production, and industrial cleaning formulations. P2O5 content minimum 54% with chlorides below 0.01% suits fertilizer manufacturing where chloride contamination would damage granulation equipment. Colourless liquid appearance confirms low iron and organic content. From 100 MT.
Grade Analysis
- FOB
- CFR
- CIF
- Industrial
- Process manufacturing
- Water treatment
Downstream Applications
Fertilizer plants dilute merchant-grade acid to 28–32% P2O5 for reaction with ammonia in DAP/MAP production. Food-grade processors further purify via solvent extraction to meet FCC specifications. Shipped in rubber-lined ISO tanks or dedicated acid tankers; heating may be required in winter to maintain pumpability.
FAQ
What is the difference between wet-process and thermal phosphoric acid?
Wet-process acid from phosphate rock + sulfuric acid contains higher sulphate and iron — suitable for fertilizer. Thermal acid from elemental phosphorus is purer, used for food and electronic-grade phosphates at significantly higher cost.
How is phosphoric acid concentration measured at discharge?
Density measurement converted to H3PO4 percentage via calibrated hydrometer, confirmed by titration against NaOH standard on the COA. Temperature correction applied for cold-climate discharge.
Can phosphoric acid be stored in stainless steel tanks?
316L stainless is acceptable for concentrations above 80% at ambient temperature. Below 50%, corrosion rates increase dramatically — rubber-lined carbon steel is preferred for dilute storage.