XXXI International Mineral Processing Congress 2024 Proceedings Page 3444 (3468 of 3836)

XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3 3601
Jameson Test rig was directly compared to the existing plant
flotation circuit. The data in Figure 2 indicated that the sin-
gle Jameson Rougher Cell yielded an increase of over 20%
in copper grade compared to the existing plant cell bank.
Jameson Cells have effectively been used for the flo-
tation of gold concentrates. Figure 3 demonstrates the
high upgrade capability of a single Jameson roughing
cell installed in an operation in the Commonwealth of
Independent States (CIS). The Jameson Cell provided an
upgrade ratio of 70:1, from 1 g/t to ~70 g/t and is able to
be reconfigured to function along the grade recovery curve
as required.
Metal Recovery (%)
Jameson Cell Conventional Cell
Point B ‘High Grade, Low
Recovery’
Point A ‘High Recovery,
Low Grade’
Figure 1. Grade recovery-curve of Jameson cell vs conventional flotation cell
0.0
5.0
10.0
15.0
20.0
25.0
30.0
35.0
0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0
Copper Recovery (%)
J500 Jameson Cell Rig Plant Grade-Recovery
Linear (J500 Jameson Cell Rig) Linear (Plant Grade-Recovery)
Figure 2. Jameson cell recoveries vs existing plant bank recoveries
Metal
Grade
(%)
)%(edarGreppoC

Previous Page Next Page

Extracted Text (may have errors)

Help

3600 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
in existing literature. The decision as to the most appropri-
ate processing solution is influenced by a number of project
specific constraints, jurisdiction legislation, existing infra-
structure, local communities and the social licence to oper-
ate, and the rise of metal sovereignty.
Project economics is also a significant consideration
in the decision as to the best approach to treating sulfide
materials, particularly for junior mining operations who
may find themselves more capital constrained compared to
their more established counterparts. Glencore Technology
(GT) works closely with a number of resource develop-
ment organisations to create flexible flowsheet solutions to
maximise financial economics of projects and make them
viable options to smaller companies that may have con-
sidered them out of reach in the past. This is achievable
through the development of several specialised technologies
suited to stagewise implementation. Stagewise implemen-
tation, as implied by the name, is the progressive design,
installation and commissioning of each processing stage,
resulting in staggered delivery schedules, more manage-
able capital expenditure (CAPEX) and expediting product
generation and therefore revenue. The first stage of opera-
tion focuses on the production of a saleable concentrate
as an interim stage to provide an initial source of revenue
while the downstream plant is fully tested, designed and
commissioned. This is followed by the production of doré
(final product) on site, after the subsequent plant stage/s
are commissioned. The expedited revenue is leveraged for
the development and commissioning of these subsequent
plant stages. In this way, the financial requirements of many
organisations can be realised, and the most appropriate pro-
cessing solution selected. This paper seeks to describe stage-
wise plant implementation and its economic considerations
compared to the traditional approach of building and com-
missioning all stages at once.
STAGES OF IMPLEMENTATION
The goal of stagewise implementation is to stagger capi-
tal and expedite revenue through the progressive design,
construction and commissioning of the plant in different
stages.
Stage 1: Concentration
Stage 1 comprises the concentration of the mineral of
interest, with froth flotation being the predominant pro-
cess applied to achieve this. As such, Stage 1 is typically
characterised by the design, construction and commis-
sioning of a flotation circuit. The design of these circuits
is underpinned by rigorous flotation testwork programs,
which are typically well understood by industry experts,
and each flotation program will uniquely vary depending
on the commodity type, mineralogy and metal dissemina-
tion within each deposit.
A challenge to the stagewise implementation of plants
lies in the design of a flotation circuit that offers the flex-
ibility to maximise grade or recovery. Initially, during stage
1, grade should be maximised to achieve a saleable concen-
trate to expedite revenue. When later stages of processing
are commissioned, the function of the flotation plant can
be changed to produce a bulk concentrate of lower grade
(where recovery is maximised), either by operating at a dif-
ferent point on the grade recovery curve or through recon-
figuration of the flotation circuit.
In the application of GT technologies, Stage 1 involves
the installation of a Jameson Concentrator ™. The term
‘Jameson Concentrator ™’ is used to describe a flotation cir-
cuit which is wholly made up of individual Jameson Cells ™.
The Jameson Concentrator ™ offers the ability to reconfig-
ure individual units (i.e., individual Jameson Cells ™) to
operate at any point along the grade recovery curve, as well
as reconfiguration of the flotation circuit as a whole. It is
this flexibility that makes the Jameson Concentrator ™ a
key facilitator of stagewise implementation. The initial test
to evaluate the Jameson Cell ™, referred to as the dilution
cleaning test, is publicly available for use by any metal-
lurgical laboratory. This test provides the opportunity to
establish a grade recovery curve for a Jameson Cell ™ and
evaluate scalping opportunities. The first stage of the test
involves floating to extinction (residence time is not a factor
in the sizing of Jameson Cells ™), and therefore the over-
all rougher recovery will always be at least the same as a
standard conventional cell (Point A, Figure 1). Subsequent
stages then simulate the froth washing capabilities of the
Jameson Cell ™, to achieve high concentrate grades relative
to a conventional cell. For illustrative purposes and to assist
in highlighting the opportunity to reconfigure the Jameson
Cell ™, a generic grade-recovery curve is shown Figure 1
(Gurnett, Swann, Martin, &Stieper, 2024). Actual plant
data to support this relationship is provided further below
in Figure 2.
A Jameson Concentrator ™, or individual Jameson
Cells ™, would be capable of being configured to achieve
high metal recoveries for a lower grade concentrate
(Figure 1, Point A), a higher-grade concentrate with lower
recoveries (Figure 1, Point B), or any point in between on
the grade recovery curve. The Jameson Cell ™ also offers
the opportunity for a significantly higher grade concen-
trate at the same recoveries compared to a conventional
cell. Evidence of this from an existing operation in regional
NSW is provided in Figure 2. During this campaign a J500

Previous Page Next Page

3602 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
Stage 2: Mechanical liberation (Ultrafine Grinding)
Stage 2 involves the mechanical liberation of precious met-
als from the sulfide matrix. As the operation progresses from
selling a concentrate to producing all doré on site, the intro-
duction of a fine grinding stage may provide an economic
interim solution prior to further processing of the sulfide
minerals. For some concentrates, depending on the uplift
in gold recovery, sufficient liberation of gold from the sul-
fide matrix may be achievable through fine grinding alone,
as was the case for Kalgoorlie Consolidated Gold Mines
in Example 1 below .This example is described in further
detail in previous publications (Ellis, n.d.) (Anderson &
McDonald, 2016).
In the application of GT technologies, Stage 2 includes
the addition of an IsaMill ™ for ultra fine grinding, whereby
strain imparted on the mineral lattice increases activation
energy to facilitate leaching under atmospheric condi-
tions. Simultaneously, the increased surface area after fine
grinding enhances leach kinetics (Hu &Chen, 2004)
(Dakkoune, Bourgeois, Po, &Joulian, 2023 Pease, Young,
&Curry, 2005).
Effective ultrafine grinding (UFG) requires the instal-
lation of specific UFG mills in order to overcome the limi-
tations of conventional mills for fine grinding. Ultrafine
grinding mills use rotating stirrers within a stationary mill
shell and are therefore significantly more energy efficient
in achieving ultrafine grind sizes compared to conventional
mills (Ellis, n.d. Kumar, Sahu, &Tripathy, 2023). The
IsaMill ™ is a well-established, highly efficient fine grinding
mill capable of achieving the tight size distribution required
to enhance the rate of downstream chemical reactions
and ensure consistency in gold recovery in downstream
cyanide leaching.
—————
Example 1: Ultrafine Grinding (UFG) using the IsaMill
as a replacement for roasting—environmental and
economic benefits
Sources: (Ellis, n.d. Anderson &McDonald, 2016).
Opportunities to eliminate an existing roaster were inves-
tigated at Kalgoorlie Consolidated Gold Mines’s (KCGM)
refractory gold processing operation (Gidji Processing
Plant). Alternatives investigated as a part of the project
included:
• Considerations for an acid plant (capture of SO2
from the roaster for generation of sulphuric acid)
• Pressure oxidation
• Biological oxidation
• Ultra Fine Grinding (UFG)
Discounted cash flow economic analyses identified that the
option of an ultra finely ground concentrate directly fed to
the cyanide leach plant had the highest Net Present Value
(NPV) return of all proposed options, and for this reason
was further investigated.
Key design parameters for this project have been sum-
marised in Table E1.1.
The replacement of the roaster was via the installation
of an M3,000 IsaMill ™ designed to achieve P80 10 µm,
and later M10,000 IsaMill ™ designed to achieve a P80
12 µm. Replacing the roasters with fine grinding enabled
0.0
50.0
100.0
150.0
200.0
250.0
300.0
0 10 20 30 40 50 60 70 80 90 100
Au Recovery (%)
Figure 3. Grade recovery of Jameson rougher cell (CIS operation)
Au
Grade
(g/t)

Previous Page Next Page

Page 1Plenary Program click to expand contents

Page 22Keynote Presentations click to expand contents

Page 163Innovation and R&D click to expand contents

Page 445Dry Processing click to expand contents

Page 562Water Management click to expand contents

Page 756Human Capital click to expand contents

Page 808Process Control, Modeling, and Simulation click to expand contents

Page 1126Strategic Minerals click to expand contents

Page 1325Geometallurgy and Process Mineralogy click to expand contents

Page 1535Extractive Metallurgy click to expand contents

Page 1842Physical Separations click to expand contents

Page 2016Flotation click to expand contents

Page 3021Energy Minerals click to expand contents

Page iTailings click to expand contents

Page 3420Plant Design click to expand contents

Page 3526Comminution click to expand contents

Extracted Text (may have errors)

Help

loading