Prolute Elution Heating System

Protherm Systems (Pty) Ltd. in partnership with KEMIX® have the “Prolute elution heating system”.

This system is specifically designed for small mines and can treat batch sizes from 500 kg up to 2000 kg carbon.

The process utilises a pressure ZADRA process, combined with a thermosiphon reboiler.
Advantages of the process is:

  • The ZADRA process is a well-known energy efficient process for recovery of gold from a
    CIL process.
  • The thermosiphon takes the place of an expensive circulation pump.
  • The automated control system gives accurate control of pressure and temperature.
  • A make-up tank is supplied for the make-up of eluant.
    Expected performance depends on site conditions, but typically heat-up times of less than 4 hours
    are possible with a total elution time of less than 24 hours.
    The system, generally in accordance with the attached PFD will be supplied as a stand-alone
    system, typically installed in one to 2 standard shipping containers.

Please note that the below video is based on a previous version. We are not building the plant “into” the container. The plant will instead be built into a steel structure and will be able to be transported using 1-2 containers, depending on the plant size. (500kg,1000kg etc)

The plant Consists of the following:

ELUTION COLUMN
The elution column is sized to give a top-down flow of eluant. Material of construction is 304
stainless steel.
Hinged flanges for loading of carbon is supplied with EPDM gaskets and quick release flanges to
speed up the loading of carbon into and out of the column. (An adder is given for knife gate
valves).
A 304SS strainer is supplied. This strainer can be upgraded to a candle strainer on request.
Design and construction in accordance with RSA/CIF-8.1 code applicable to pressure vessels
constructed in South Africa (based on ASME VIII). Design construction & testing are subject to 3rd
party surveillance by A.I.A. Price for AIA is included.

ELECTRIC HEATER
A suitably sized electric heater is supplied for the system:
500 kg: 68 kW
1000 kg: 111 kW
1500 kg: 144 kW
2000 kg: 180 kW
Size of the heater is sufficient to heat up the system in less than 4 hours and to maintain the
thermosiphon flowrate once electrowinning has commenced.
The heater has both a removable bundle and individual removable elements. This allows for the
quick replacement of the entire bundle or a more economic replacement of individual elements.
The elements is spaced in such a way that allows for easy cleaning on the eluant side – an
application, which is well known for its high fouling nature.
Material of construction for the wetted parts are 304 stainless steel.

ELECTROWINNING CELL
The electrowinning cell is developed by KEMIX®, complete with rectifier. Designed
specifically for the Prolute.
Material of construction for the wetted parts are 304 stainless steel.
Design and construction in accordance with RSA/CIF-8.1 code applicable to pressure vessels
constructed in South Africa (based on ASME VIII). Design construction & testing are subject to 3rd
party surveillance by A.I.A. Price for AIA is included.
Note: Loaded carbon with high concentrations of copper may require mild steel anodes, which is a
consumable.

PRESSURE CONTROL VALVE
A suitably sized control valve is supplied to allow for accurate control of pressure,
temperature and to maintain the thermosyphon effect.

ELUANT MAKE-UP AND FEED PUMP
A 304 stainless steel make-up tank is suplied for the make-up of eluant together with a
stainless steel feed pump for both mixing and transfer of the eluant from the make-up tank
to the column.

CONTROL PANEL & MCC
The plant is supplied with a control panel and the necessary switch gear for all equipment. Cabling
internal to the package is supplied but may be removed for transport and may require re-cabling in
accordance with assembly drawings on site.
The panel will allow for easy control of the system, including semi-automated start-up and shut￾down procedures.

PIPING
Piping and valves interconnecting items supplied generally as shown as per attached PFD
Eluant solution piping in 304 stainless steel materials. Flanges will collars with carbon steel
backing flanges.
Valves on elution piping are ball valves in 304 stainless steel.
Pressure relief valve and bursting disc as shown on equipment supplied.

INSTRUMENTATION
All instruments inclusive of battery limits is supplied, complete with required fittings i.e. pockets,
isolating valves and chemical seals as required.

ENGINEERING SERVICES PROVIDED

  • Process design & control narrative
  • Sizing / rating all of equipment items.
  • General arrangement drawing.
  • P & I D
  • Detailing of equipment for manufacture of fabricated items.
  • Equipment specifications and item data sheets for procured items
  • Panel and wiring diagram, as applicable for fired heater
  • Provision of equipment mounting details and loading data so as to enable the design and
    construction of civils by others.
  • Provision of motor list
  • Provision of instrumentation list, as is applicable to scope of supply
  • Operating manual for plant operation and control.

COMPLETE PLANT
The elution system is erected within 2 structural steel skids.
These skids will fit within standard shipping containers for transport.
Transport to site, off-loading and installation on site is excluded.
Each plant is pre-assembled and tested in the workshop before dis-assembly for transport.
Instruments will be shipped in solid wooden crates.

OPTIONAL EXTRAS
A list of optional extras for your consideration is below. Please contact us for further information:

  • Add flow control with thyristor control.
  • Crawl beam and chain hoist
  • Secondary heater loop with different heating sources
  • Removable candle type, wedge-wire screens
  • De-ionization plant
  • Knife gate valves on carbon transfer nozzles
  • Wash bath/system for elements
  • Mag flow on circulation line
  • Regeneration Kiln
  • Acid wash column

EXECUTION & SUPPLY

  • Procurement and progressing of equipment manufacture and supply
  • Quality Assurance in accordance with contract requirements
  • Readying for shipment, packaging & crating for ocean freight.
  • Transport to site, but off-loaded and installed by others

WORK EXCLUDED

  • Any insulation and cladding. In our experience this is best done on site after warm
    commissioning.
  • Cabling to the MCC.
  • Supply of treated water either for testing purposes or fill on site.
  • Carbon transfer equipment

REFERENCES
Recent elution heating systems /elution equipment supplied by Protherm Systems are as follows:

  • Goldfields Tarkwa-Ghana- through Lycopodium (Pty) Ltd
  • Newmont Ahafo-Ghana – through Lycopodium (Pty) Ltd
  • Randgold Loulo-Mali- through MDM (Pty) Ltd
  • Bogoso Gold-Ghana-through GRD Minproc (Pty) Ltd
  • Newmont Akyem-Ghana-through Lycopodium (Pty) Ltd
  • Rio Narcea-Tasiast-Mauritania- through Senet cc
  • ECM Varvarinskoye-Kazakhstan- through Senet cc
  • Cluff (Angovia Mine)- Ivory Coast- though Hazron (Pty) Ltd
  • Cluff (Kalsaka Mine)-Burkina Faso- though Hazron (Pty) Ltd
  • Etruscan Resources (Youga Mine)-Burkina Faso- through GBM Minerals
  • Goldfields Tarkwa (Phase lV Expansion) – Ghana- though Engineering Project Company
    (Pty) Ltd
  • IAMGold Essakane Mine- Burkina Faso-through GRD Minproc
  • B2 Gold Namibia through Lycopodium (Pty) Ltd
  • SA Precious Metals (Pty) Ltd
  • Modderfontein Gold