The objective is to increase the total production and the quality of high quality refractory materials in order to limit the EEC's imports and dependence in these fields.
The Glomel factory produces 65000 tonnes of concentrated andalousite a year from 620000 tonnes of mineral. In order to achieve consistant production levels and product quality, a long term study has been carried out with the aim of: characterizing waste to determine the quantity of recoverable andalousite; determining which waste is potentially more suitable for treatment; finding a new continuous process to recover andalousite of at least production line quality.
In the laboratory and subsequently at pilot level, a great deal of interest was taken in a flotation method. This allowed high quality concentrates to be recovered from wastes which were presumed useless using other mineralogical techniques. Other wastes from the factory were tested in order to monitor the efficacy of the process. In wastes containing between 1.3% and 7% ferrous oxide, and between 45% and 55% aluminium oxide, the use of the flotation method consistantly allowed improvement of the relative values (at least 59% aluminium oxide and 0.5 to 0.9% ferrous oxide).
This project will involve research into new processing methods to improve the production in existing units and the development of new production units in the EEC (France or Spain). Technical solutions will be developed in response to the major constraints (low mineral content, low yield of current processes, high investment costs, competition from non EEC countries, etc).
The processing methods studied will include new unitarian operations such as the column flotation and inverse flotation of andalousites, the flotation of granular andalousites (0.3 to 1 mm), the gravimetric separation of 0.3 to 1 mm, the concentration of the poor tailings and the white burning products. This project forms a logical extension to the corresponding project under contract MA1M-0070 which, with the same partners, was essentially a study to improve knowledge about the GLOMEL deposit, mineralogical studies, the recovery of fine tailings, the kinetics of rough floating, optimization of the rewashing conditions and processing control.
This project concerns research into a new treatment method to construct new production units, which will in particular require the following :
the development of new processing methods for the coarse fractions (column flotation, flotation of coarse grains, gravimetric separation, etc);
an inverse flotation method to improve recovery of minerals rich in andalousite;
new methods for purification of the concentrates in order to obtain products for new refractory applications;
and a method for preconcentration of the poor finings which are currently not processed etc.
Funding SchemeCSC - Cost-sharing contracts