StackCell™
HydroFloat™
FGB-104
Particles approximately 850 micr
Division is developing and commercializing new products based on metallurgical first principles that will actually allow the energy
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MINE WATER MANAGEMENT findings.“ We all need to help drive this shift from thinking of water as a consumable good to managing water as a reusable asset.”
Water clean up
Veolia Water Technologies’ proprietary HPD ® Evaporation and Crystallization technology is being used to recover lithium from a mining waste stream, reducing environmental impact and producing a valuable byproduct in sodium sulphate, for North American Lithium Inc. This is a hydromet mining operation in La Corne, Quebec, Canada for the production of lithium carbonate( Li 2CO 3).
Veolia Water Technologies installed the sodium sulphate crystallisation circuit. The primary objective is increased recovery of lithium while producing a sodium sulphate( Na 2SO 4) byproduct. In doing so, the project will benefit from recovering two products from what, previously, was a waste stream, thereby reducing the environmental impact and making the project a commercially viable source of valuable lithium carbonate.
“ The system design is based on Veolia’ s vast experience with this form of production coupled with complex mixed salts solubility, energy efficiency, and reliability. This ultimately enabled Veolia to provide the right solution to benefit both North American Lithium and the local environment,” commented Klaus Andersen, CEO
of Veolia Water Technologies Americas.
The multistage process includes MVR Falling Film Evaporation, two-stage crystallisation in a HPD Draft Tube Crystalliser and a HPD MVR Crystalliser to produce anhydrous sodium sulphate that is dried for sale. This solution allows the client to recover useful resources in an energy efficient way and ensures a complete and well running lithium carbonate production plant.
Clean TeQ has entered into a landmark agreement with Fosterville Gold Mine Pty Ltd to design, supply and commission a 2 million litre / d Clean TeQ DeSALx mine water treatment plant. The award of the contract followed a period of extensive due diligence and test work conducted by Fosterville to validate the efficacy of Clean TeQ’ s DeSALx system for the treatment of mining process waters. The value of the contract is A $ 3.5 million and serves as a significant milestone for the Clean TeQ Water division.
The company notes that " sustainable water management is becoming critically important in the mining industry as environmental regulations are tightened globally and water scarcity increases. The Fosterville water treatment plant is an important reference project for Clean TeQ’ s DeSALx technology, which is expected to add significant momentum to the growing pipeline of Clean TeQ Water projects."
Fosterville operates the Fosterville gold mine near Bendigo, northwest of Melbourne. During
mining groundwater is produced and stored at surface in limited capacity dams on the mine site. To create a more sustainable water management strategy, Fosterville approached Clean TeQ to provide a system that will treat the mine water to match the quality of the region’ s underlying aquifer. Fosterville can then use managed aquifer injection( MAI) to return the water to its natural source, or alternatively, use the treated water from the Clean TeQ plant for further treatment and subsequent recycling and re-use of the water.
The Fosterville water treatment plant comprises an integrated precipitation and continuous ionic filtration process( DeSALx). The precipitation process removes arsenic and antimony from the water as a coprecipitate. The water is then treated by the DeSALxprocess to remove hardness, sulphate, and other dissolved metals. DeSALx technology is ideal for complex mine wastewater treatment. The DeSALx process can be used as a standalone or as a pretreatment for membrane based water treatment systems.
As the DeSALx byproduct is gypsum-based, it is compatible with Fosterville’ s established lime treatment facility and provides a zero-brine water treatment solution. Design of the Fosterville water treatment plant is already underway, with equipment supply, installation and commissioning all scheduled for 2018.
Clean TeQ continues to pursue a range of other water treatment opportunities including:
This Changes Everything!
HydroFloat Separator
Recovers virtually all particles which exhibit greater than 1 % hydrophobic surface expression
Overflow Coarse Mineral
Air
Underflow Coarse Tails
Particles approximately 850 microns
THE BENEFITS OF
COARSE PARTICLE FLOTATION
IMPROVEMENTS IN FLOTATION TO REDUCE ENERGY
Eric Bain Wasmund Global Managing Director Eriez Flotation Division
Particles approximately 850 microns
As the worldwide mining enterprise moves to processing ore bodies with lower head grades, the volume of ore that must be ground and floated to produce the same amount of product increases by at least an equivalent amount. Using existing technology, this means that the energy requirement for grinding and flotation will increase as well. As an innovative flotation equipment manufacturer, the Eriez Flotation
EFD’ s HydroFloat ™ Separator radically improves the traditional sulfide processing circuit through Coarse Particle Flotation. Unlike conventional flotation, the HydroFloat Separator recovers particles as large as 800 microns with as little as 1 % mineral surface expression. By rejecting the balance as“ coarse” tailings, much of the recirculating load is eliminated, thus greatly increasing mill capacity … with NO loss in mineral recovery!
Coarse Particle Flotation using EFD’ s HydroFloat Separator can:
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Rejects only those particles that have no hydrophobic surface expression requirements to be dramatically decreased. These are not the kind of incremental second order improvements achieved by simply making bigger unit operations based on current technology, but major first order improvements that are possible through a major re-think of the flotation process, which hasn’ t changed fundamentally in 100 + years.
The first of these is the HydroFloat™, a high-efficiency, aerated, fluidized-bed flotation cell that is capable of recovering coarse, semi-liberated particles. Benchmarking the performance of the HydroFloat against a conventional stirred tank cell in a number of studies has shown a dramatic improvement in the flotation of coarse particles, as an example see the recent paper by Mehrfert *. This approach allows for recovery at a much coarser size( and rejection of a coarse tail) which results in a significant reduction in grinding; the major energy consumer in the concentrator. The potential benefit to reduce comminution energy consumption are now well accepted, and major mining companies are now looking at the HydroFloat as a type of ore sorter to develop a coarse throwaway tail.
Another technology that is being commercialized for base metals is the StackCell™, which was introduced a decade ago into the U. S. coal industry. Developed by Dr. Michael Mankosa and Dr. Gerald Luttrell( U. S. Patent No. 8,960,443), the StackCell is a two-stage flotation device. A cross-section of the StackCell is shown in Figure 1 on page 2. The first stage( center of tank) is an energy intensive, low residence time chamber consisting of a rotor-stator( 4) that creates high turbulence to mix air and feed slurry together( 1). In this stage, the kinetics for particle-bubble collection are maximized in a zone that can flow in one direction into the second stage, with no short circuiting. The second stage is a settling tank with overflow launders( 2) and wash water( 7) that allows for bubble-particle separation from the pulp into the froth phase in a fluid environment that allows for froth washing and minimizes particle bubble detachment.
A campaign using a train of three 0.60-metre diameter StackCells in series for a low grade copper ore was reported at the 2016 Denver SME conference( Christodoulou, 2016). A photograph of a similar installation is shown in Figure 2. The objective was to evaluate the StackCell as a low-energy, high-capacity alternative for a multi-stage rougher application for slow-floating ores and to compare the kinetics( recovery and grade) with a Denver lab cell, which is the industryaccepted standard for scaling up conventional stirred flotation cells.
More information is available at www. eriezflotation. com
For more details download these White Papers at www. EriezFlotation. com 1.604.952.2300