MINING CHEMICALS
charges such as calcite, phosphate and fluorspar;
and in reverse flotation of heavy impurity minerals
from feldspar and other similar industrial
minerals.”
“Commodity” fatty acids are currently the most
widely used collector type in reverse feldspar
flotation due to the absence of better alternatives,
according to Gorken and Parker, but they come
with poor selectivity, high dosage requirements
and associated operational difficulties, such as
equipment smearing and the need for collector
removal from concentrates for specific
applications, Gorken and Parker said.
Due to these issues, modifiers have been
introduced to enable continued use of fatty acid
collectors, further complicating the flotation
process and increasing costs, Gorken and Parker
said. “Therefore, it is imperative that new, more
efficient alternatives to century-old fatty acids be
novel dewatering agent that, it says, specifically
targets sinter feed piles and iron flotation
concentrate.
Laboratory drainage tests using the FLOTICOR
dewatering agent on iron ore sinter feed reported
a potential improvement in moisture reduction of
10.2%, according to Clariant. In a subsequent field
trial, a relative reduction of 10.5% moisture (1%
absolute) was achieved (as is shown in the photos
right).
The amount of water that was dewatered on the
sinter feed pile versus the control pile that did not
have the dewatering agent is also emphasised in
the photos.
Clariant said the dewatering agent is under
further field trial evaluation ahead of future, more
formal test work.
“Dewatering of iron ore flotation concentrate
has been conducted by the Clariant Mining
developed.”
This led to the development of the JCDP, which
has seen the typical two-stage reverse feldspar Solutions team in Brazil and preliminary
indications are that moisture content can be
reduced by 2% under laboratory lead filtration
flotation process simplified to a single-stage
process in Turkey – an industry first, according to
Gorken and Parker.
“Arkema-ArrMaz’s CustoFloat ® custom blend testing,” the company said.
Additional confirmation testing for operational
qualification is being carried out and will lead to
collectors specifically formulated to the producer’s
unique ore mineralogy yielded substantial
performance improvements,” they said. “Collector
dose was reduced by 30-50%, and significant
increases in recovery and grade were observed.
Both collectors improved overall operational
efficiency and cost-performance considerably,
while streamlining reagent dosing and handling.”
The custom blend collectors developed under
this JCDP provided enhanced capacity utilisation;
improved flotation efficiency; better feldspar
recovery and concentrate grade; simpler and
easier application compared with current industry
standards; improved flotation selectivity; better
material handling; and regulatory
compliance/cost avoidance, according to Gorken
and Parker.
The JCDP also showed collaboration between
mineral processing operations and reagent
formulators to develop tailor-made collectors
yields better results compared with commodity
collectors, Gorken and Parker remarked.
Dewatering concentrate
industrial trials later in 2020, according to Clariant.
Addressing crud and scale
On top of improving mineral processing using
novel chemicals, Solvay’s customers are looking to
it to both extend the life of processing equipment
and improve said equipment’s effectiveness.
Its ACORGA ® CR60 series reagents are
processing aids designed to help solvent
extraction operations reduce crud formation from
turbidity in leach solutions (patent-pending). They
have also been found to improve phase separation
in solutions with high colloidal silica, according to
Solvay.
Its MAX HT ® sodalite scale inhibitor,
meanwhile, is a “best-in-class” product that
eliminates sodalite scale from heat exchangers
throughout the Bayer Process and contributes to
the sustainability of the alumina industry,
according to the company.
A liquid reagent, ACORGA CR60 affects the
formation of the solid-stabilised organic/aqueous
emulsion and therefore significantly reduces – and
in many cases stops – crud formation, Solvay
Dewatering and water reuse/recycling are
influencing not only OEM and mineral processing
equipment design; they are also impacting the explained.
In a six-month (pilot and commercial) trial with
Lisbon Valley Mining Company at its copper
operation in Utah, USA, the following benefits
development of chemicals.
According to Clariant, mining operations have
been demanding increasingly challenging
operational targets for the dewatering process, were demonstrated at the solvent extraction
operation, according to paper given by Solvay at
the 2020 SME Annual Conference and Expo:
n Minimum levels of crud were maintained at
requiring lower humidity for concentrates.
The Clariant Mining Solutions’ applications
technologies team in Brazil has developed, in extraction stages, without the need for crud
pumping and processing from the stages;
n ACORGA CR60 eliminated plant “upsets” and
conjunction with one of its iron ore customers, a
40 International Mining | MAY 2020
the need for flow rates reduction against
A field trial in Brazil of Clariant Mining Solutions’
novel FLOTICOR dewatering agent led to a 10.5%
moisture (1% absolute) reduction in iron ore
sinter feed
increased turbidity events (ore curing, raining
events, pad challenges, etc);
n As a result of the reduced crud levels, pregnant
leach solution throughput increased 7%
throughout summer and winter seasons; and
n No impact on downstream processes such as
electrowinning and leaching.
Solvay says its MAX HT scale inhibition
technology has benefited global alumina
refineries for over a decade by improving
operating efficiency, saving energy costs, reducing
carbon footprints and lowering freshwater usage.
It has only recently been introduced to China’s
alumina industry, leading to some impressive
results.
Solvay explained: “China produces over half of
global alumina output, and the industry has a
rapidly growing need to improve efficiency and
reduce its environmental impact, as competition
intensifies and more stringent regulations are
being enforced.”
This has led the industry to adopt new
technologies in order to compete on a global
stage and reduce its environmental footprint.
The introduction of MAX HT, Solvay says, has
provided “outstanding scale inhibition
performance in the liquor evaporation process” in
China.
With MAX HT, it’s estimated that some 0.03 t of
steam for evaporation can be saved, on average,
for every 1 t of alumina produced (fresh water is
heated to produce steam for evaporation. Thus,
with MAX HT, fresh water, as well as the energy
and resultant CO 2 associated with steam
production, are reduced).
So far, Solvay’s scale technology has been used
at over 30 evaporation lines in Chinese alumina
refineries, bringing significant economic benefits
to refineries, while contributing to reducing their
environmental impact, it said. IM