Show LEACHING NON SULPHIDE COPPER ORES 4 leaching non sulphide copper ores with sulphur dioxide by charles E van barneveld and edmund S leaver technical paper has just been published by the department part ment of the interior through the bureau of mines this process was devised to provide a cheap and efficient method for treating the so called porphyry copper ores of the southwest which generally contain both sulphide and non sulphide copper minerals mixed in such proportions that they can only be satisfactorily treated by a method which will concurrently recover both the sulphide copper and the non sulphide copper the importance of the matter may be judged Z by the fact that more than one half of the copper produced in a recent year in in arizona and new mexico amounting in value to came from the so called porphyry low grade deposits it is thought by the writers that the sulphur dioxide leaching process developed by the southwest experiment station of the bureau in cooperation with the miami copper company and the arizona copper company is suitable and commercially available for a wide range of the ores above described summed up the advantages of leaching with sulphur dioxide are as follows the plant is compact and not expensive pens ivd there are no installation difficulties power requirements quire ments are light operation is simple and easily controlled there are no delicate adjustments or critical points percolation difficulties common to leaching are entirely avoided perfect contact is assured between the finest ore particles and the reagent thus there is excellent utilization of the rea reagent za ent which is very cheap in consequence the process may be extended to ores with so much acid soluble gangue that they could be treated at a profit by ordinary sulphuric acid leaching the process is as applicable on a relatively small as on a large scale and small scale operation does not necessitate an undue increase in operating cost |