Advertisement

Fertilizer research

, Volume 12, Issue 1, pp 85–98 | Cite as

Partially acidulated phosphate rocks made from phosphoric acid using direct acidulation-granulation techniques

  • A. C. Braithwaite
  • D. A. Rogers
Article

Abstract

Partially acidulated phosphate rocks were produced by spraying phosphoric acid onto North Carolina phosphate rock of three finenesses (unground, medium, or finely ground) in a pan or drum granulator. This ‘direct acidulation-granulation’ procedure resulted in free-flowing granular products using laboratory acid up to stoichiometric levels of 30% (unground), 45% (medium) and in excess of 50% (fine). However, when less pure works grade acids were used the maximum levels of acidulation were reduced to 15%, 30% and 45% respectively with a corresponding greater difficulty in producing good granules.

Mature product analyses indicated an analytical bias with granule size, the larger granules containing greater quantities of soluble phosphate in most instances. Physical tests on mature products indicated that all granules produced were inferior to those of the ‘traditional’ New Zealand fertiliser single superphosphate.

Keywords

Phosphoric Acid Great Difficulty Phosphate Rock Product Analysis Soluble Phosphate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Braithwaite, AC (1983) Physical and Chemical Properties of Phosphate Rocks Partially Acidulated with Phosphoric Acid, NZFMRA 19th Tech. Conf. Proc. 256–266Google Scholar
  2. 2.
    Braithwaite AC (1985) Processing and Analytical Factors in the Preparation of Partially Acidulated Phosphate Rocks using Various Phosphoric Acids, NZFMRA 20th Tech. Conf. Proc. 20–23Google Scholar
  3. 3.
    Braithwaite AC (1986a) A comparison of fertilisers made by partially and fully acidulating phosphate rocks with phosphoric acid. NZJ Tech. 2:37–42Google Scholar
  4. 4.
    Braithwaite AC (1986b) Processing aspects of production of partially acidulated phosphate rock fertilisers. Submitted to Fert ResGoogle Scholar
  5. 5.
    Charleston AG, Rogers J (1980) Experimental Determination of Granule Strength — Method and Results, NZFMRA 4th Res. Symp. Proc. 154–158Google Scholar
  6. 6.
    Hammond LL, Chien SH, Polo JR (1980) Phosphorus availability from partial acidulation of two phosphate rocks. Fert Res 1:37–49Google Scholar
  7. 7.
    Quin BFC (1985) The MAF ‘National Series’ Forms of Phosphate Trials, NZFMRA. 20th Tech. Conf. Proc. 604–628Google Scholar
  8. 8.
    Rajan SSS (1985) Partial acidulation of an ‘unground’ phosphate rock 1. Preparation and characteristics. Fert Res 8:147–155Google Scholar
  9. 9.
    Rajan SSS, Quin BFC (1985) Partially Phosphoric-Acidulated Phosphate Rocks as Fertilisers for Pasture. NZFMRA. 20th Tech. Conf. Proc. 411–424Google Scholar
  10. 10.
    Sinclair AG, Saunders WMF (1982) The Importance of Sulphur and a Soil Test for it, Ruakura Farmers Conf. Proc. 41–43Google Scholar

Copyright information

© Martinus Nijhoff Publishers 1987

Authors and Affiliations

  • A. C. Braithwaite
    • 1
  • D. A. Rogers
    • 1
  1. 1.Fertiliser Manufacturers' Research AssociationNew Zealand

Personalised recommendations