Physical method of upgradation for low grade wolframite pre-concentrate from Degana, Rajasthan

Tungsten is a strategic metal and mostly used in defence. It is also used in cutting tools, industrial, electrical, textile and leather sectors. India's tungsten reserves are very limited and the only workable deposit is restricted to Degana in Rajasthan. Tungsten deposit occurs in association with metamorphic rocks and granite igneous rock throughout the world. At Degana, two types of deposit are being worked at, one being quartz load wherein wolframite is mineralised in quartz vein and the other is finely disseminated tungsten mineralisation in the granite body. The sample under investigation belonged to off-grade tungsten pre-concentrate - I (PC - 1) produced at Degana Plant site, assaying 14.50% WOe 20.20% SiO, and 4.13% S. The objective of this study was to find the upgradation conforming to DMRL specification i.e. final wolframite concentrate with >65.0% WO,, and S and SiO, < 1.0% each. Detailed studies indicated that grinding the feed to 200 mesh followed by sulphide flotation at 4.5 and 8.0 pH and repeated vanning of non-sulphide could produce a wanner concen¬trate assaying 64.8% WO,. 1.0% SiO, and 3.0% S with a distribution of 48.8% WO3 in it. Thorough desliming followed by sulphide flotation and then treating on vanner times could produce a concentrate analysing 68.47% WO j, 0.5% SiO3 and 0.48% S which conforms to the DMRL sped¬fications.