Fertilizer research

, Volume 18, Issue 1, pp 63–70 | Cite as

Investigation of factors affecting caking tendency of calcium ammonium nitrate fertilizer and coating experiments

  • Ali Lafci
  • Kemal Gürüz
  • Hayrettin Yücel
Article

Abstract

Caking of fertilizers is an important problem both to manufacturers and users. Manufacturers must recycle the caked fertilizer to the process resulting in an extra cost and users may have difficulties during the application of the fertilizer to the soil. In the first part of this study major factors which influence caking of a commercial grade calcium ammonium nitrate (CAN) fertilizer were investigated with a laboratory caking apparatus kept in a controlled atmosphere. It was observed that the caking tendency of CAN fertilizer increases almost linearly with pressure exerted on the fertilizer and with moisture content of the fertilizer at a temperature of 35 °C. The results indicate that the phase transition of ammonium nitrate between crystalline forms IV and III plays a significant role in caking of CAN since caking tendency is greatly reduced below the phase transition temperature which occurs at about 32 °C. In the second part of the study, the effectiveness of some coating materials to reduce the caking tendency of CAN fertilizer were tested. Among the materials tested, kieselguhr gave the most satisfactory result under the experimental conditions employed.

Key words

Calcium ammonium nitrate caking coating fertilizer 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Silverberg J, Lehr J R and Hoffmeister G J (1958) Microscopic Study of the Mechanism of Caking and its Prevention in Some Granular Fertilizers. J Agr Food Chem 6: 442–448Google Scholar
  2. 2.
    Sjöling C (1972) Mechanism of Caking of Ammonium Nitrate Prills. J Agr Food Chem 20(4): 895–899Google Scholar
  3. 3.
    Thomson D C (1972) Fertilizer Caking and Its Prevention, Proceedings of the Fertilizer Society No 125, LondonGoogle Scholar
  4. 4.
    Fertilizer Manual (1980) Development and Technology Series No 13, New YorkGoogle Scholar
  5. 5.
    Moldovan L, Popovichi N and Chivu G (1969) The Technology of Mineral Fertilizers. The British Sulphur Corp Ltd, LondonGoogle Scholar
  6. 6.
    Varma S and Panwar K S (1968) Effect of Phase Transition of Ammonium Nitrate on the Storage Behaviour of Calcium Ammonium Nitrate. Technology (Sindri) 5(3): 161–165Google Scholar
  7. 7.
    Adams J R and Ross W H (1941) Relative Caking Tendency of Fertilizers. Ind Eng Chem 33(1): 121–127Google Scholar
  8. 8.
    Varma S, Jarayaman R and Chakravarty K R (1959) Keeping Quality of Fertilizers: Part I — Caking of Ammonium Nitrate. J Sci Ind Res 18B(3): 118–122Google Scholar

Copyright information

© Kluwer Academic Publishers 1988

Authors and Affiliations

  • Ali Lafci
    • 1
    • 2
  • Kemal Gürüz
    • 1
  • Hayrettin Yücel
    • 1
  1. 1.Department of Chemical EngineeringMiddle East Technical UniversityAnkaraTurkey
  2. 2.Turkish Fertilizer Industries CorporationAnkaraTurkey

Personalised recommendations