190 likes | 400 Views
New Development in Dihydrate -Hemihydrate processes : first industrial experiences of the new Prayon DA-HF process. Prayon: Tibaut Theys, Dorina Fati, Olivier Schrevens Grupa Azoty: Agata Tarnowska, Monika Zienkiewicz. Contents. Introduction Test Design Test Results Lessons Learned.
E N D
New Development in Dihydrate -Hemihydrate processes:first industrial experiences of the new Prayon DA-HF process Prayon: Tibaut Theys, Dorina Fati, Olivier Schrevens Grupa Azoty: Agata Tarnowska, Monika Zienkiewicz
Contents • Introduction • Test Design • Test Results • Lessons Learned
Introduction • Five process routes exist to produce phosphoric acid (DH, DH-HH, HH, HRC and HDH) • Technologies are in public domain • Prayon invests in R&D to improve plant efficiency and profitability • One high newcomer: DA-HF process
Introduction • DA-HF pilot tests showed promising results • High efficiency • High P2O5 in acid • Stable operation • Two industrial tests organised to confirm results and gain industrial know how • In collaboration with GrupaAzoty (Poland)
Industrial Test Design Di Attack – Hemi Filtration Hemi Filtration 32% P2O5 3% SO3 Di Attack 36 % P2O5 h = 97 – 98%
Industrial Test Design Plant design - Dihydrate FC Nominal capacity: 150 tpd P2O5 4 compartments 225 m³ Slurry cooled by flash cooler Filter : 40 m² useful – dry discharge 1 2 3 4 Filter
Industrial Test Design FC Plant design – DA-HF Steam H2SO4 1 2 3 4 Filter
Test Process Parameters • DH residential time: 3h30 @ 100% capacity • HH residential time: 1h20 @ 100% capacity • Solids content DH: 25 – 30% • SO3 DH: 0.7 to 1 % • SO3 HH: 2.5 to 5 % • Temp DH : 74 – 76 °C • Temp HH : 97 – 99 °C • %P2O5 acid produced: 32 -34%
Test Results • Quality of acid and gypsum • Calcium sulphate filterability • Efficiency • Plant operation
Test Results – DH Crystals • Small individual crystals • No clusters • Slurry easy to pump
Test Results – HH Crystals • Clusters • Ball shape • Aggregates easy to filter
Test Results – Efficiency • Industrial values observed: 97 – 98% • To be compared with a DH process results by GA : 91 – 94%
Test Results – Plant Operations • Some difficulties due to filter hopper not designed for HH operation (solids accumulation) • Operators could easily operate the plant • Start-up and shut downs are as easy as for DH process • Flash cooler to be operated at lower pressure
Lessons learned for conversion of existing DH plant • Most DH plants can be converted to DA-HF technology • Main changes to be considered: • Installation of a conversion tank • Improvement of cooling capacity • Adaptation of filter
Conclusion DA-HF process can be operated on an industrial basis Increase of plant efficiency : about 2 to 4 % Acid produced with higher P2O5 content : above 32% P2O5 Existing DH plant conversion can be considered
Thank you for your attention ! Contact: Tibaut THEYS Tel: +32.4.273.93.41 Fax: +32.4.275.09.09 prt@prayon.be