Development of a safety denitration method to remove nitric acid from mixtures

  • Y. Kondo
Article

Abstract

In order to reduce heat and off-gas generation rates at early stage of the chemical denitration of high and medium level liquid wastes from the reprocessing of nuclear fuel, a safety denitration method, Pre- and Mild-denitration technique, was originated. In the Pre-denitration step, the formic acid of 0.06 to 0.3 times nitric acid concentration ([HCOOH]/[HNO3]=0.06 to 0.3) was poured into a nitric acid solution at 80°C and denitration was initiated (Pre-denitration). Then additional formic acid was injected into the Pre-denitrated solution at a constant injection rate in 80°C and the solution mixture was heated up to the boiling condition (Mild-denitration). In the Mild-denitration step, the denitration reaction was smoothly initiated and a leak out of solution from a abrupt boiling has never occurred. The maximum heat and off-gas generation rates were about 50 cal/s-l and about 1.01/min respectively even in the 10M nitric acid solution. These measured values were low enough to ensure the safety operation of denitration.

Keywords

Boiling Formic Acid Nitric Acid HNO3 Injection Rate 

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References

  1. 1.
    A. Ortins, D. Bettencour, A. Jouan, CEA-R-3663, 1969.Google Scholar
  2. 2.
    H. Krause, KFK-1030, Kernforschungszentrum Karlsruhe, 1970.Google Scholar
  3. 3.
    R. F. Bradly, C. B. Goodlet, DP-1299, E. I. Du Pont de Nemours & Co., 1972.Google Scholar
  4. 4.
    T. V. Heary, J. Appl. Chem., 8 (1958) 553.Google Scholar
  5. 5.
    INV.S. Drobnik, DE-PS 1935273, July 1969.Google Scholar
  6. 6.
    K. Holze, Proc. 3rd. Intern. Symp. Loss. Prev. Safety. Prom. Proc. Ind., Basle SSCI, 1980, p. 1413.Google Scholar
  7. 7.
    G. Proter, J. Chem. Phys., 19 (1951) 1278.Google Scholar
  8. 8.
    M. Kubota, I. Yamaguchi, H. Nakamura, J. Nucl. Sci. Technol., 16 (1979) 426.Google Scholar
  9. 9.
    V. L. Longstaff, K. J. Singer, J. Chem. Soc., 54 (1954) 2610.Google Scholar
  10. 10.
    E. G. Orebaugh, DP-1417, E. I. Du Pont de Nemours & Co., 1976.Google Scholar
  11. 11.
    F. H. Pollard, K. A. Holbrook, Nature, 177 (1956) 799.Google Scholar

Copyright information

© Akadémiai Kiadó 1999

Authors and Affiliations

  • Y. Kondo
    • 1
  1. 1.Department of Chemistry and Fuel ResearchJapan Atomic Energy Research InstituteNaka-gun Ibaraki-kenJapan

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