mer - 07/10/2015
Akira OTSUKI propose deux sujets de Master :
Development of flexible flotation process to enhance fine grain greisen ore beneficiation
Aims and Background
This project aims to develop flexible flotation process to beneficiate fine grained greisen. Greisen deposits are formed by transformation of granitic rocks by metal containing fluids. Consequently greisen consists of quartz and various micas with feldspar residua. Ore minerals are cassiterite, wolframite and sometimes lithium mica with Sn, W, Li as main and niobium, tantalum and molybdenum as minor metal components. Sulphides contain Cu and As. Greisen ores are, in general, relatively low in grade as well as finely disseminated and intergrown. The main bottlenecks of greisen ore processing by flotation are:
- Insufficient liberation of valuable components (cassiterite) connected with over-grinding of ore minerals;
- Low floatability contrast cassiterite-quartz/silicates;
- Environmental hazardous flotation reagents; and
- Difficult flotation of finest grained cassiterite associated with complicated flotation regime.
These bottlenecks led to production of low grade concentrates of tin (4-10 % Sn), impossibility of recovery of by-products (W, Nb, Ta, Mo) and low processing yield, resulting in insufficient economic values. This will apply innovative technology approached for greisen ore processing including
- Ultrasonic technology for intensification of finest grain flotation;
- New reagents, especially for cassiterite flotation.
Method
This study will consist of the following 3 main components.
1) To perform testwork on intensified Cassiterite flotation at finest grain size, and separate quartz from mica, feldspar and hematite; and
2) To determine partition curves and simulate separations at different cut grades to establish the upgrading curves.
Keywords
Low grade ore; floatability contrast; silicate; cassiterite; by-product