Extraction of Uranium Nitrate with 30% (v/v) Tributyl Phosphate in Kerosene in an Pilot Annular Pulsed Disc-and-Doughnut Column—Part I: Hydraulic Performance

ABSTRACT

The annular pulsed disc-and-doughnut column (APDDC) is an important extraction contactor used in the PUREX process. In this work, hydraulic investigation was carried out in a stainless-steel APDDC, with 30% (v/v) tributyl phosphate (TBP)-kerosene + uranium nitrate + nitric acid + water as the test system. Two operation modes with aqueous phase and organic phase as the continuous fluid were performed separately. The equations, which were previously developed for 30% TBP-kerosene + nitric acid + water system in aqueous phase continuous operation mode, were presently used to predict the holdup, the Sauter drop diameter, the flooding holdup, the flooding throughput, and the operating regimes in both operation modes. Good agreement with the experimental data was observed because the wettability of the dispersed phase on the internals in both the operation modes was similar with that in the aqueous phase continuous operation mode in the previous work. An exception is the flooding properties of the organic continuous operation mode because of a different flooding mechanism. And so new equations were proposed to calculate the flooding properties for the organic continuous operation mode.

KEYWORDS:

• Annular pulsed disc-and-doughnut column
• holdup
• Sauter drop diameter
• flooding
• operating regimes
• internal wettability