VANCOUVER, Sept. 11, 2013 /CNW/ - Kivalliq Energy
Corporation ("Kivalliq", TSX-V: KIV) today provided an update
on ongoing metallurgical and beneficiation studies for Kivalliq's
340,268 acre Angilak Property in Nunavut Territory. This update summarizes
preliminary results from work performed on the Lac 50 Trend
deposits, including: metallurgical testing of the J4 and Lac 50
zones as well as characterization studies related to optimal ore
sorting methods.
"Results from ongoing metallurgical work at Lac 50 are
encouraging," stated Chuck Edwards,
Director of Metallurgy at AMEC. "Optimizing sulphide
recovery, plus improvements to alkaline leach kinetics using oxygen
as oxidant, could have a positive impact on reducing costs
associated with potential treatment options."
Key Point Summary:
- J4 Zone flotation achieved an optimum sulphide recovery of
99.2% in alkaline solution at a grind size of 100% passing 140 mesh
(106 µm).
- Positive alkaline leach results on J4 Zone indicate
rapid uranium extraction: 92.3% in 12 hours, 95.2% in 24 hours
and 96.7% in 48 hours.
- Using improved alkaline leach parameters defined by the J4 Zone
testing, retesting of the 2012 Lac 50 composite upgraded the leach
extraction of uranium to: 91.7% in 12 hours, 95.1% in 24 hours and
96.4% in 48 hours. (previous results released February 28, 2013)
- J4 Zone sulphide flotation and alkaline leach results are
consistent with other Lac 50 deposits.
- Preliminary ore sort characterization of rock specimens from
Lac 50 deposits indicates that radiometric sorting will be very
effective. Radiometric characterization analysis demonstrates a 56%
reduction in mass with 98% U3O8
recovery.
Metallurgical Results Demonstrate High Uranium Recoveries and
Rapid Leach Kinetics
In 2012, the Saskatchewan Research Council ("SRC") commenced a
metallurgical testing program on core from Kivalliq's Lac 50 Trend.
The program objectives were to maximize uranium extraction through
the removal of sulphides using flotation and optimizing the
alkaline leaching processes. Results from the 2012 metallurgical
program were very encouraging with high U3O8
recovery rates and the production of a low impurity final
yellowcake product. (see Kivalliq news release of February 28, 2013)
In 2013, metallurgical testing was expanded to include a
composite sample from the newly discovered J4 deposit. The goal was
to compare alkaline leach parameters of the J4 Zone to previous
test work, while continuing to develop optimal grinding, sulphide
flotation and leach conditions. A 26.0 kilogram composite derived
from 44 split drill core pulp rejects was submitted to the SRC
Mineral Processing Group for metallurgical analysis. Pulp samples
used in the composite were selected from 17 holes drilled along 650
metres of strike length at J4 Zone. A head grade sample taken from
the composite and analyzed by total digestion ICP at SRC is shown
in Table 1.
Table 1 J4 Zone Composite Sample ICP Total
Digestion Assay (ppm)
U |
Ag |
Pb |
Cu |
Zn |
Mo |
Zr |
Total S |
Sulphide |
7040 |
43.5 |
3885 |
6075 |
3030 |
3090 |
608 |
21200 |
13700
|
Sulphide flotation on J4 Zone composite material tested variable
grind sizes in water and alkaline solution respectively. An optimum
sulphide recovery of 99.2% was achieved in alkaline solution at a
grind size of 100% passing 140 mesh (106 µm).
Alkaline leaching of J4 Zone flotation tails achieved rapid
uranium extraction of 86.7% in 6 hours, 92.3% in 12 hours, 95.2% in
24 hours, 96.7% in 48 hours, 97.2% in 72 hours, and 97.5% in 96
hours under the following conditions: 100% passing 140 mesh grind,
70oC, 50% solids slurry, 50 g/L
Na2CO3 and 20 g/L NaHCO3 solution
chemistry and oxygen at 300 kilopascals as oxidant.
Using the same optimized conditions, an additional test was
conducted on a sample from the 2012 Lac 50 composite (but at 100%
passing 200 mesh grind as per 2012 composite preparation). When
compared to the 2012 result leach kinetics improved with uranium
extractions of 83.6% in 6 hours, 91.7% in 12 hours, 95.1% in 24
hours, 96.4% in 48 hours, 97.0% in 72 hours, and 97.3% in 96 hours.
Figure 1 compares alkaline leach kinetics from 2013 to that of
2012.
Figure 1. Optimized Leach Kinetics for J4 Zone
composite and 2012 Lac 50 composite samples
Preliminary Ore Sorting Investigation Shows Amenability to
Radiometric Sorting
In May 2013, Kivalliq engaged
TOMRA Sorting Inc. (TOMRA) in Surrey,
British Columbia to characterize a set of rock specimens
from the Lac 50 Trend uranium deposits using Radiometric (RM), Dual
Energy X-Ray Transmission (DEXRT), conductivity and magnetic
susceptibility (EM) and visible spectrum (Optical) sensors.
Preliminary ore characterization studies were performed to
determine whether mineral sorting technology could efficiently
identify and segregate uranium bearing minerals.
"We are very pleased with the success of preliminary radiometric
sorting." stated Jeff Ward,
President Kivalliq Energy. "Larger bulk testing using
production-scale sorting methods will now be considered as a
processing option to concentrate uranium bearing rocks at Lac
50."
Kivalliq delivered to TOMRA a 1.45 kilogram suite of high grade,
medium grade, low grade and waste specimens, comprised of 138 sized
rock chips (2.0 cm to 3.0 cm across), collected from half split NQ
drill core intersections representative of the Lac 50 Trend uranium
deposits. Characterization measurements were carried out on the
entire suite using the RM, DEXRT, EM and Optical sensors. Following
sensor characterization, individual rock specimens were shipped to
SRC for analysis by total digestion ICP. The average grade of the
sample was 1.06% U3O8.
Theoretical perfect sort recovery curves for the samples were
obtained by ordering the individual rocks in descending
U3O8 grade. Using the order of the perfect
sort and the mass and grade of each specimen, curves were
calculated for a theoretical perfect recovery, concentrate grade
and tails grade for the samples. These results are then compared to
the grade and recovery curves for each sensors tested.
Using radiometric sensors proved to be the most effective method
for sorting Lac 50 samples by U3O8 grade. RM
characterisation was performed at Hazen Research Inc. (Hazen) in
Golden Colorado where a RM bench top
test system was configured to simulate a full scale RM sorter. The
theoretically perfect sort curve showed 98.3% recovery of
U3O8 at a mass recovery of 44% (or 56% mass
rejected with only 1.7% loss of U3O8). The
actual short integration RM sort recovered 98.0% of
U3O8 at a mass recovery to concentrate of 44%
(56% mass rejected with 2.0% loss of total
U3O8) and is almost identical to a
theoretical perfect sort recovery curve. Concentrate and tails
grades were 2.37% U3O8 and 0.03%
U3O8 respectively. Figure 2 shows comparative
RM sort curves for the Lac 50 sample.
Figure 2. Comparative RM Sort Curves -
Recovery of U3O8 vs. Mass Pull
QA/QC
The SRC facility operates in accordance with
ISO/IEC 17025:2005 (CAN-P-4E), General Requirements for the
Competence of Mineral Testing and Calibration laboratories and is
accredited by the Standards Council of Canada. The samples are analyzed by SRC's
ICP-OES multi-element ICP1 assay method. ICP1 results are
reported in parts per million (ppm). 1 ppm = 1g/tonne, 10,000 ppm =
1%. TOMRA ICP U assays in ppm were converted to %
U3O8 as follows: % U3O8
= ppm U x 0.01179
TOMRA (formerly Commodas Ultrasort and Terra
Vision) are leaders in the specialized field of sensor-based
sorting technology for the mining industry. Experience from 15 test
facilities worldwide have led to significant advances in in
automated material identification and sorting for the mining and
mineral processing industries.
Hazen performs research and development for
clients in the mineral, chemical, energy, and environmental fields.
The company serves clients worldwide on projects ranging from
bench-scale experiments to continuous pilot or demonstration
plants.
Jeff Ward, P.Geo,
President of Kivalliq and a Qualified Person for Kivalliq, has
reviewed and approved the scientific and technical information
contained in this release. For disclosure related to the inferred
resource for the Lac 50 Trend uranium deposit, please refer to
Kivalliq's news release of March 1,
2013.
About Kivalliq Energy Corporation
Kivalliq Energy Corporation (TSX-V: KIV) is a
Vancouver-based uranium
exploration company holding Canada's highest-grade uranium resource
outside of Saskatchewan's
Athabasca Basin. Its flagship
project, the 340,268 acre Angilak Property in Nunavut Territory,
hosts the Lac 50 Trend with a NI 43-101 Inferred Resource of
2,831,000 tonnes grading 0.69% U3O8, totaling
43.3 million pounds U3O8. Kivalliq's
comprehensive exploration programs continue to advance the Lac 50
Trend and demonstrate the "District Scale" potential of the Angilak
Property. Kivalliq's team of northern exploration specialists have
forged strong relationships with sophisticated resource sector
investors and project partner Nunavut Tunngavik Inc. ("NTI") in
order to advance the Angilak Property. Kivalliq was the first
company to sign a comprehensive agreement to explore for uranium on
Inuit Owned Lands in Nunavut Territory, Canada and is committed to building
shareholder value while adhering to high levels of environmental
and safety standards and proactive local community engagement.
For Angilak Property data tables, maps and
figures: www.kivalliqenergy.com/angliak/technical/images/
To view a short video related to the Angilak Property, Evolution of
the Lac 50 Trend, click here: Evolution of the Lac 50
Trend
On behalf of the Board of Directors
"Jim Paterson"
James R.
Paterson, CEO
Kivalliq Energy Corporation
Kivalliq Energy Corporation is a member of the
Aurora Mineral Resource Group of companies, for more information
please visit www.auroraresource.com.
Neither the TSX Venture Exchange nor its
Regulation Services Provider (as that term is defined in the
policies of the TSX Venture Exchange) accepts responsibility for
the adequacy or accuracy of this release.
Certain disclosures in this release, including
the budget and exploration program proposed for the Angilak
Property, constitute forward-looking statements that are subject to
numerous risks, uncertainties and other factors relating to
Kivalliq's operations as a mineral exploration company that may
cause future results to differ materially from those expressed or
implied in such forward-looking statements, including risks as to
the completion of the plans and projects. Readers are cautioned not
to place undue reliance on forward-looking statements. Other than
as required by applicable securities legislation, Kivalliq
expressly disclaims any intention or obligation to update or revise
any forward-looking statements whether as a result of new
information, future events, or otherwise.
Cautionary Note concerning estimates of Inferred
Resources:
This news release uses the term "inferred
resources". Inferred resources have a great amount of uncertainty
as to their existence, and great uncertainty as to their economic
and legal feasibility. It cannot be assumed that all or any part of
an Inferred Mineral Resource will ever be upgraded to a higher
category. Kivalliq advises U.S. investors that while this term is
recognized and required by Canadian regulations, the U.S.
Securities and Exchange Commission does not recognize it. U.S.
investors are cautioned not to assume that part or all of an
inferred resource exists, or is economically or legally
mineable.
SOURCE Kivalliq Energy Corporation
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