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Title
of Technology to be offered
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Recovery
of Tungsten Values from Low Grade Ore
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Type
of Technology
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Indigenous
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Area
of Technology
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Materials and Material
Sciences
|
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Details
of Present/existing Technology. Shortfall/Technological gaps in the
existing technology
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Due
to high density and high temperature properties, tungsten is a very
important metal both strategically and industrially. Most of the
present demand is met through imports of powder and concentrates. The
available Indian deposits are of very low grade ranging from 0.04 to
0.2 % WO3 against the commonly exploited ore grades of 0.5%
WO3 world
over.
The existing process for
the beneficiation of tungsten ore basically consists of processing of
the ore by physical methods like gravity and magnetic separation to
get the concentrate. But considering the low metal content and the
fine dissemination of tungsten bearing minerals in the gangues in the
run-of-mine ore, normally it is difficult to get the desired grade of
the concentrate. Alternatively, efforts of obtaining a high grade
concentrate by fine sized pulverisation and multi-stage processing
leads to high losses of tungsten values. There has been a need to
develop a suitable process for the recovery of tungsten values from
lean grade ores. The new technology addresses this problem.
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Approach
adopted in new technology to evade technological gap in the existing
one
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The new technology
developed at the National Metallurgical Laboratory, Jamshedpur
adopts an integrated approach combining physical and chemical
beneficiation methods to get the final product : ammonium para
tungstate. In order to avoid tungsten losses in the fine size ranges,
prior to final concentration, pre-concentration of the ore is carried
out at relatively coarser size.
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Advantage/Benefits
of new technology (with in 150 words)
|
The
advantages of this technology includes the following :
v
Higher
recovery of tungsten values and the process results in the final
product as ammonium para tungstate by a combination of physical &
chemical methods.
v
Reductions
in energy towards comminution of ore by carrying out pre-concentration
at relatively coarser size.
v
Reduction in
water consumption because pre-concentration is a dry processing step
etc.
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Brief
description/abstract (150 words)
|
Extensive characterisation
and physical & chemical beneficiation
studies were undertaken at the National Metallurgical Laboratory,
Jamshedpur on different tungsten ore samples from a typically low
grade deposit located in Degana, Rajasthan, India. Based on these
studies a process has been developed for the recovery of tungsten
values from the low grade tungsten ore. The process basically consists
of pre-concentration of the ore at relatively coarser size by dry
magnetic separation, further upgradation by gravity methods followed
by chemical processing to ammonium para tungatate.
The
basic process flow-sheet is as shown below
ROM
SAMPLE ð
 COMMINUTION & SIZING ð
PRE-CONCENTRATION ð
COMMINUTION & CLASSIFICATION ð
CONCENTRATION CHEMICAL
BENEFICIATION ð
AMMONIUM PARA TUNGSTATE
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Area
of application
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Mineral, Metals &
Materials
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Details
of specification application
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Lamp filaments, High speed
tools, Wear resistant parts, Engine valves, Circuit breakes Chemicals
for textiles etc.
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Status
of Specific Development
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Laboratory/Pilot plant
scale
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Ecological/Environmental
Impact (if any, specify
briefly)
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No toxic effluents are
generated in this process and as such it has no adverse effect on
environment
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Patenting
details
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Yet to be patented
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Extent
of Commercialisation
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The process has not been
commercialised
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Technology
Transferring Agent
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NML/CSIR
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Technology
Transfer Assistance Offered (Optional)
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Evaluation of raw
materials, Process know-how, Process flow-sheet, Equipment details.
Advice and assistance in setting up the plant and operation on
separate terms and conditions.
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Key
words
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Tungsten ore, Low grade,
Finely disseminated, Physical beneficiation, Chemical processing,
Recovery, Ammonium para tungstate, Process flow-sheet.
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Country
of origin
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India
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