Development of an experimental methodology for sulphide self-heating studies and the self-heating tendency of Vale’s Voisey’s Bay Concentrator products

• Existing methods for self-heating studies were reviewed.
• A new methodology for sulphide self-heating studies was developed.
• The self-heating tendency of Voisey’s Bay Concentrator products were evaluated.
• A practical method of mitigating self-heating was recommended.
• Results from this evaluation demonstrate this method is superior to other methods.

Moist sulphide ores, concentrates and tails tend to self-heat under favourable conditions. Several serious incidents have been reported as a result of sulphide self-heating occurrences in mining, mineral processing and smelting operations.An experimental methodology has been developed to evaluate the rate of self-heating of sulphide materials, and to study factors that may be used to mitigate sulphide self-heating. Factors studied included moisture content, degree of compaction, air humidity, availability of oxygen by varying the air flowrate, direction of air flow within the sample bed and purging with nitrogen gas. High degree of compaction was shown to be the most effective and practical means of mitigating sulphide self-heating.