DA-HF

About

Cutting-edge process to produce phosphoric acid with a high recovery efficiency

The Prayon DA-HF Process is a modern process developed and industrially implemented by Prayon. It is an economic and efficient solution to produce phosphoric acid and valuable gypsum as a co-product.

It consists in the attack of the phosphate rock under dihydrate conditions. Then, the gypsum slurry is converted to hemihydrate by the addition of sulfuric acid and steam in a specific circular reactor designed by Prayon. Hemihydrate slurry is filtered on a Prayon tilting pan filter to recover a good-quality calcium sulfate.

Depending on the rock processed, the ex-filter acid strength is typically 32-34% P2O5 and the typical P2O5 recovery efficiency is 97%.

Advantages
When should we select Prayon DA-HF Process?

Low investment cost

Especially considering the revamping of an existing Dihydrate plant

High P₂O₅ recovery

Low P₂O₅ content in the phosphogypsum

Suitable for cement and building applications

Self-drying phosphogypsum

With a final moisture around 10-12%

Limited grinding of the rock

Low cadmium in the product acid

Recommended
When should Prayon DA-HF Process be applied?

Where medium- to high-cost rock is accessible

Where energy cost is rather high

Steam and electricity

Where gypsum disposal is limited and/or where a potential market for gypsum has been identified

Cement or building applications

To increase production capacity by minimum 20%

With limited changes in an existing Dihydrate plant
For more information

Download our brochure

Brochure: DA-HF - Prayon Technologies
EN

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