HIGH PROFILE
Some of the CiDRA team onsite at BHP ' s Carrapateena operation
CiDRA ’ s P29 journey to commercialisation continues
It has been a busy year so far for CiDRA Minerals Processing with ongoing work on its revolutionary P29 technology , as Paul Moore reports having spoken to their management team
CiDRA continues to make headway with its groundbreaking P29 technology . The P29 system is based on the development of a new processing route which at its heart has an innovative new material that attracts and holds mineralised particles based on the same hydrophobic properties that cause them to float during flotation . Unlike systems that take effect further downstream , grind-circuit roughing offers the possibility of directly reducing the recirculating load in grinding mills , increasing mill throughput by 20 % or more at a constant primary plant grind size .
OZ Minerals ( now BHP ) and CiDRA in Q1 2023 commissioned a front-end engineering and design ( FEED ) study for a full-scale implementation of CiDRA ’ s Grind Circuit Rougher technology at the Carrapateena mine to remove coarse material from the grind circuit circulating load , enabling an increase in plant throughput . Worley was selected to provide FEED services for the project .
To date , Worley and CiDRA have completed 60 % of FEED design for the planned Carrapateena 3,000 t / d . commercial plant . CiDRA has also conducted a site visit in support of the FEED study and the pilot plant placement and integration on top of weekly meetings between the partners . CiDRA told IM it has also been rapidly increasing its P29 dedicated team to support the contract with BHP Carrapateena and meet the demand for testing and studies work with other miners . Aside from Carrapateena , CiDRA is also conducting commercial bench test programs and value proposition studies with two other major copper mines , both in Chile .
Paul Rothman , President CiDRA Minerals Processing commented : “ The level of interest in the industry is still very strong . These mining groups want to understand better what coarse grind can mean for their operations in terms of increased throughput . For strategic reasons and
How does CiDRA ’ s P29 work ?
The technology , methods and potential of the technology were detailed in a white paper recently posted by CiDRA . IM also spoke to Bob Maron , CiDRA Chief Commercial Officer for more detail on the technology and its potential earlier this year : “ It started out with us looking for an alternative to conventional flotation . How could we capture particles better than the current flotation technology with bubbles , which has been around for over 100 years ? It involves the use of a media as a substrate . We started with spheres and it has evolved into using an open cell polyurethane foam in 12.5 mm cubes . An engineered hydrophobic coating is applied to the substrate enabling it to attract hydrophobic particles in the same way that a bubble does . However , it does that much more strongly than a bubble ; it doesn ’ t burst like a bubble ; and because it is open cell foam , the amount of surface area per unit volume is much higher . The substrate foam we use is in the form of small cubes which is mixed with the ore slurry in a rotating drum . The slurry penetrates around and through the foam and contacts the foam surface and the reagent chemical , similar to that used in flotation , attracts the hydrophobic particles .”
The foam substrate can be engineered with different pore sizes and the media can be tailored for the particle size distribution for the specific application . The pore size in the media defines the available surface area for mineral attachment and is analogous to the bubble surface area in froth flotation . The advantage of engineered foam media as a mineral collection mechanism is that it can be optimised for durability , surface energy , compliance , and flexibility , as well as the shape and size of the media . The industrial reticulated foam is coated and cured through industry standard processes ; the cured foam sheets are then cut into cubes and vacuum packed for shipping .
The contactor is a simple mixing device designed to contact the mineral slurry with the collection media . Embodiments of the contactor are a sump / pump and pipe or a horizontal rotating drum . The circuit configuration will be a function of the feed slurry mineralogy , rheology and application space .
The loaded media is separated from the slurry via a screen , either attached to the end of a horizontal drum contactor or as a standalone vibrating screen . A recycled water rinse is used to remove the entrained gangue from the media which results in high upgrade ratios and low mass recoveries . The media is dewatered prior to the mineral removal stage with either a vibrating screen or a ‘ low g ’ basket centrifuge . The mineral is removed from the media by passing the loaded media and release agent through a series of disc pumps . The release agent used in the mineral removal stage is reclaimed using a centrifuge or nano filtration stage . The reclaimed release agent is returned to the process .
While the technology has the potential to replace flotation in theory , CiDRA started by addressing the most immediate application that can bring the highest value to its customers and so developed a novel mineral separation solution called Grind Circuit Rougher™ ( GCR ) which leverages the P29 platform . This can take a significant stream of coarse particles from the hydrocyclone underflow that would normally go back to the ball mill and recover those particles that have some valuable mineral content , down to very low copper grades . The rest of that gangue can then be rejected , and those copper bearing particles can go through a light regrind and then onto final concentrate . You are saving volume of material going through the mill and therefore making significant energy savings .
40 International Mining | OCTOBER 2023