THE RESEARCH WILL GIVE THE POSSIBILITY OF IMPROVING THE TREATMENT OF THE ANDALOUSITE MINERALS BY OBTAINING A BETTER QUALITY OF THE CONCENTRATE.
THE ECONOMIC BENEFIT FOR THE EC WILL RESULT FROM THE FACT THAT ABOUT 150.000 TONNES PER YEAR OF ANDALOUSITE MINERALS ORE USED FOR MANUFACTURING HIGH GRADE REFRACTORY BRICKS OR REFRACTORY COMPOUNDS. THIS MINERAL IS IMPORTED FROM SOUTH AFRICA; IT COULD BE PRODUCED IN AN E.C. COUNTRY THUS REDUCING THE TRADE BALANCE DEFICIT.
The following have been investigated:
improvements in the knowledge of GLOMEL deposits to improve the quality of minerals for use in industry;
new quarrying methods;
improved treatment performance (valuable waste recovery, control and improvement in factory treatment);
new less expensive treatment processes (eg flotation, high intensity magnetic separation in a humid atmosphere, pneumatic methods, etc).
The aim of the reseach was to increase the quality of European andalusites.
With respect to improvements in the knowledge of the deposit, a computer program has been developed to obtain a better method for exploitation of the open pit.
Improvements in recovery and quality involved the design of a rather complex flowsheet for the plant (this is due to the necessity of obtaining large particles of andalusite). 6 middlings are produced by the different process for andalusite recovery. The study started with the richest tailing that contained 66% andalusite, and later other tailings were tested following the same procedure.
Mineralogical studies have been carried out involving:
andalusite liberation size.
The following basic studies have also been developed:
kinetics of flotation for pyrite and andalusite;
optimization of recleaning conditions;
influence on flotation when using industrial water;
Influence of the desliming size before andalusite flotation;
influence and limit on flotation when recycling the industrial water;
collector concentration measurement method;
collector residual concentration in the various stages of the andalusite flotation;
andalusite recovery from the low grade tailings (direct flotation).
All the laboratory results have then been verified at the Glomel industrial pilot, for all the tailings involved.
Overall this has led to the development of a new process using direct flotation for the recovery of andalusite.
Accurate laboratory studies have been carried out to define the main parameters of the andalusite flotation process. Continuous flotation tests have been carried out to check the process and produce concentrates for customers' tests.
The research has allowed:
control of the quarry exploitation;
improvement and regulation of the concentrate quality;
optimization and increase in the andalusite recovery;
improvement of the whole plant process;
decreases in the operating cost of sold products;
the study of reverse flotation to proceed.
THE RESEARCH IS DIVIDED IN THE FOLLOWING STEPS:
1) A BETTER KNOWLEDGE OF THE DEPOSITS, CONCERNING PARTICULARLY THE RELATION FEED ORE/PLANT PRODUCT CHARACTERISTICS IN THE PRESENT PLANTS;
2) IMPROVEMENT OF THE PERFORMANCE OF THE PRESENT PROCESSING SYSTEMS BY:
2.1. LABORATORY FUNDAMENTAL STUDIES,
2.2. LABORATORY SYSTEMATIC FLOTATION TESTS,
2.3. STUDIES ON THE INDUSTRIAL PLANT.
3) VERIFICATION BY CONTINUOUS TESTS ON THE PLANT OF THE TREATMENT SYSTEMS STUDIED IN LABORATORY.
Funding SchemeCSC - Cost-sharing contracts