Eldorado's Solvent Extraction Plant at Port Radium, N.W.T.
R. TREMBLAY ; P. BRAMWELL
The Port Radium leaching plant of Eldorado Mining and Refining, Limited, produces 4'50 t. / d. of sulphuric acid leach liquor containing l. 73 g. / I. U 30 8 . After solvent extraction, the waste solution is discarded at 0.002 g. / l. U30s for a recovery of 99.8 to 99.9 per cent. The solvent is acidified with weak sulphuric acid, loaded to 4.5 g. / l. U80:1 in three-stage extraction, scrubbed with water, and stripped with soda-ash solution in single-stage stripping. Caustic removes the U3O8 from the pregnant strip solution as a precipitate. The slurry is filtered, re-pulped with water, and re-filtered. The pressed precipitate at 81 to 82 per cent equivalent U30s is dried and packaged. The carbonate filtrate is cooled to remove sodium sulphate build-up and carbonated to convert excess caustic. Reagent consumptions are 4.1, 0.22, and 0.39 pounds per 1,000 gallons of pregnant solution for Diesel oil, amine, and alcohol, respectively. Caustic consumption averages 1.3 to 1.4 pounds per pound U~Os. Extraction and stripping is accomplished in sheet-iron mixer-settlers lined with Phenoline. Piping on both circuits is Schedule 80 polyvinyl chloride. Valves are straightway Buna N lined with American Hycardiaphagms. Extensive instrumentation ensures good metallurgy with a minimum of variations and labour. Mixing in a continuous organic medium and careful acidity control are required to minimize third-phase formations. Heating the precipitate slurry is conducive to good filtering in Perrin presses with neoprene-coated, rolled-steel sectors. Sodium sulphate is crystallized from carbonate filtrate solution by batchwise cooling to 54 °F. with lake water
amine, amine, Port Radium Solvent, red alarm, sodium carbonate, sodium sulphate, Emulsion, Emulsions, Extraction, flow, Phase, Pump, Pumps, Water, Waters