Xanthate Replacement: Case of the Sossego Mine

摘要

The concentration of sulfide ores by flotation has an important role to meet the global demand for many metals, including copper, lead, zinc, nickel, etc. Consequently, the chemical inputs, among them collectors, frothers, modifiers, regulators, and others, play a fundamental role in this process, without such reagents process efficiency would be strongly affected.Among the different chemical families used as collectors in the sulfide flotation, xanthates are the most used in the mining industry. Such compounds can be used as single collector or together with other collectors to increase their performance.Due to their chemical and physical properties, xanthates require some care for their use, among them: specially designed warehouses are necessary due to their spontaneously combustible character; in the presence of water or moisture, xanthates degrade very rapidly as a function of temperature to form carbon sulfide, which in turn is classified as a highly flammable toxic compound. Due to this, xanthates can experience transportation difficulties with shipping companies are increasingly reluctant to accept it. In addition, once empty, packaging becomes a hazardous material, so its disposal or reuse become a problem.This paper discusses the results of the evaluation of the partial and total substitution of PAX in the copper flotation, as well as the dosing way (single or staged dosage) and frother/collector ratio. The ore used in this study is a typical sample from Vale - Sossego mine. The evaluation of the products followed a stage of laboratory tests for a pre-selection and then they were submitted to industrial tests for certification. Successful results led to the approval and consequently use alternative product to xanthate.