Study On Theory And Process Of Reverse Floatation Of Andalusite With Gangue Silicates

With rapid development of our industry, continuous expanding of andalusite application, rational development and utilization of andalusite resources is important to relieve contradiction between supply and demand of andalusite and to promote the development of our industry. The silicate gangues in andalusite ore, such as sericite and kaolinite, seriously disturb the separation of minerals. As there are relatively less researches in the area of andalusite ore including the upside gangues, studying the basic flotation behavior, effect and mechanism of andalusite, sericite and kaolinite can control the flotation process better and improve the quality of andalusite flotation concentrates.This paper studies effects of several collectors, many inhibitors and metal ion on the flotation of andalusite, sericite and kaolinite. Besides, the article also discusses the mechanism between mineral surface and collector or metal ion by several measurements such as zeta potential testing, FTIR and thermodynamic calculation. The main conclusions of the thesis are indicated as follows.Results of single mineral tests and measurements show that the floatability of sericite and kaolinite is better than that of andalusite under the system of collector lauryl amine and XM-1 and pH 5.0～6.0. The existence of metal ion exacerbates differences in flotation properties among andalusite, sericite and kaolinite. The flotation properties of andalusite are close to that of sericite under the sodium petroleum sulfonate system and kinds of metal ion existing. According to several inhibitors tests, we find that it is difficult to find the inhibitor which can efficiently prevent sericite activated by metal ion out of activity. The combination of metal ions has an inhibiting effect on floatability of andalusite and sericite over the entire pH domain. The electrostatic adsorption interaction between mineral and dodecylamine weakened as combined metallic ion made the zeta potential of andalusite and sericite shift markedly towards the positive direction. The flotation of andalusite and sericite were depressed intensively because of the Al3+,Fe3+,Ca2+ and Mg2+ producing the corresponding hydroxide precipitation. The reason why kaolinite was activated has something to do with pH, crystal structure of minerals and so on. In a word, the flotation properties of sericite and kaolinite are better than that of andalusite under the system of collector lauryl amine and XM-1, which make inverse separation of andalusite, sericite and kaolinite. However, under the sodium petroleum sulfonate system The flotation properties of andalusite are close to that of sericite.Results of actual ore tests show that the qualified andalusite products can be obtained and the grade of Al2O3 in flotation concentrates reached to as much as 54.83% by use of a technology, which consists of table concentration to deslime and take off peptide, make high intensity magnetic separation to remove iron from the table middlings, reverse flotation to silicate impurities such as sericite and kaolinite, direct flotation to andalusite. Using a new self-made collector XM-1 to separate sericite and kaolinite by reverse flotation from andalusite ore is so effective that the andalusite concentrates are up to the standard in the unprocessed pulp flotation. The unprocessed pulp flotation combination technology is simple, the andalusite products can be qualified and the recovery is higher.