Abstract
Preliminary laboratory scale gravity concentration tests using jig and table, and some flotation tests were performed on tungsten ore from Hidaka mine, Yamaguchi Prefecture so as to clear up an amenability of the ore to tungsten concentration. Results obtained were as follows
1) Jig test on -10+20 mesh and table test on -20+35 mesh showed an inferior results owing to incomplete scheelite liberation from gangue minerals. Good tungsten concentrate of 14.00% WO3 was found from the table test on -35+65 mesh sample with 65.1% recovery.
2) From flotation tests on -100 mesh sample, addition of sodium carbonate to control pulp alkalinity to pH 9 was preferable to that of sodium hydroxide.
3) Best flotation concentrate on -100+150 mesh sample among seven sized fractions was obtained, showing the grade of 52.77% WO3 and 98.5% recovery. Coarser or finer size fractions than the -100+150 mesh showed lower concentrate grade and recovery due to poor scheelite liberation or slime entrapment into the tungsten concentrate.
4) Cleaning tests up to 4th cleaning showed the final flotation concentrate of 20.37% WO3 without middling recycling from low grade ore of 0.68% WO3.
5) Combined use of sodium carbonate with sodium silicate was beneficial in getting high grade flotation concentrate of 34.94% WO3 with fairy good recovery of 89.0%.
6) Since slime consisting mainly of chlorite gave poor flotation results, preliminary desliming was found to be of use to the better flotation performance.
