Study on the effects of purification of noncrystalline micro silica powder using flotation process

Micro silica powder is separated and purified using flotation process.In order to define the optimum nano quartz flotation conditions, a study is made of the effects on purification of the material produced by dosage of collector, different kinds of metal cationic activators, pH value of pulp, agitating intensity, introduction of nano bubbles, etc.Test results indicate that with the flotation machine working at a speed of 2,000r/min, a pH value of 12, a collector dosage of 1.5g/L, and a dosage of activator(CaCl₂)of 5×10^-3 mol/L, the recovery and grade of nano quartz are as high as 70.2% and 93.45% respectively.In the case of using a nano bubble generator-flotation machine integrated pulp circulation system to enable the pulp to be sufficiently aerated with nano bubbles, under otherwise identical conditions, the recovery of nano quartz is 9.7 percentage points higher than the case of using deionized water.It well demonstrates that introduction of nano bubbles can help improve to a certain extent flotation effect because of increased bubble-fine particle and interparticle collision and adhesion probability.