Modified Sodium Silicate On The Impact Of Molybdenum Ore Flotation

In recent years, considerable advancement has been achieved in China's molybdenum ore processing technology. In practice, sodium silicate is cheaply used as gangue depressant especially for silicates, but its huge dosage makes the tailing water unsinkable and no recycled water can be used. For this problem, ordinary sodium silicate was the modification and application in the floatation of molybdenum ore were discussed in this thesis.The experiments on modified sodium silicate and floatation show that the best inorganic modifier is sulfate, and the optimum ratio with sodium silicate is 2:5. That is 1kg/t sodium silicate is used with 0.4kg/t sulfate. The sodium silicate should be modified for 10 minutes under 600r/min.The contrast study on flotation of the ore from ChaoYang XinHua Molybdenum shows that without the modified sodium silicate, the dosage of sodium silicate is 2 kg/t, kerosene is 210g/t and 2# oil is 375g/t. But with the modified sodium silicate, the dosage of sodium silicate is reduced to 1 kg/t, kerosene is 150g/t and 2# oil is 312.5g/t. A open circuit was done under the condition of one rougher, one scavenger and four cleaners. For ultimate concentrate, the final molybdenum grade of is 39.8%, the recovery of is 36.67% and the productivity is 0.21%. For the tailing, the molybdenum grade of is 0.028%, the recovery is 11.86%, and the productivity is 97.41%. Compared with ordinary sodium silicate, under the same flotation condition, the experiments with modified sodium silicate can not only reduce the amount of flotation reagent but improve the technic indexes of molybdenum ore flotation. Contrast tests on tailing sedimentation show that under the same experimental conditions, the average settling rate of the tailings from the above open circuit is 1.21cm/min, but the tailings from the factory can't nearly settle. So the problem of tailing settlement difficulties is obviously improved. The research on the action mechanism between the modified sodium silicate and gangue minerals shows that the main function between the modified sodium silicate and silicate minerals are adsorption negative charged sillicic acid and H3SiO4- on the surface of minerals. The nature of the mineral surfaces are changed to strongly hydrophilic after the adsorption。Above all, the modified sodium silicate can both decrease the amount of flotation reagents and improve the flotation indexes. Moreover, it can improve the mill environment, the safety of the tailings dam and the condition of water used for concentration.