| 摘要 |
In the production of intensively colored lapis lazuli pigment, suitable directly for coloristic purposes, flotation to separate pyrite and carbonates is followed by flotation to (a) remove mica; (b) recover lapis lazuli in 2 stages, using sodium fluoride as regulator; and (c) purify lapis lazuli concentrate in 3 or more stages. The stages are carried out in the presence of an amine with a 14-20C chain as collector and at pH 5.5-10.5 and the finest, 0.010-0.020 mm, fractions are removed with hydrocyclones between the flotation stages. Production of intensively colored lapis lazuli pigment, which can be used directly for coloristic purposes without after-treatment to make the color deeper, from natural crude rock containing mainly associated minerals or waste from precious stone production involves crushing the raw materials in a milling cycle, making a pulp, removing slime, and multistage flotation to: (1) separate pyrite; (2) separate carbonates; and (3) using a collector/frother containing alkylamine to recover lapis lazuli. After the second flotation stage: (a) mica is floated out; then (b) the lapis lazuli is recovered in a direct primary and secondary flotation, with addition of a sodium fluoride as regulator; (c) the lapis lazuli concentrate is purified by primary and secondary flotation and then by one- or multistage purification flotation. All the flotation stages are carried out in the presence of an amine with a 14-20C chain as collector and at pH over 5.5 and under 10.5 and the finest fractions of about 0.010-0.020 mm are removed with hydrocyclones between the flotation stages. |
