Au AND Ag Recovery




TecProMin S.A. has wide experience in engineering, equipment supply, training and start-up in gold-silver ore dressing plants and also counts on the technical supportprovided by Summit Valley Equipment & Engineering (SVEE), world leader in noblemetals refining plants.This strategic and exclusive association in Latin America with SVEE addsexperience and state-of-the-art technology in processes which are all transferred to achieve optimum quality and efficient projects.



TecProMin staff  includes  all engineering disciplines and may develop any projectat any stage.

TecProMin has participated in several ore dressing projects surveys covering from design and control of metallurgical tests through conceptual, basic and detail engineering as well as feasibility studies and EPCM projects development,including all engineering disciplines: process, piping, electrical &instrumentation, mechanical and civil/structural discipline, includinginspection tasks and assembly audito to guarantee the project success.

Engineering studies are carried out depending on the customer´s needs, wether as a complete plant project or as a complement to the supply ofsome particular equipment from our represented companies :


Our services are complemented with training activities (theoretic-practicaltraining to operators and maintenance management) and start-up andcomissioning consultancy.

TecProMin S.A. may supply equipments for ore dressing plants from representedcompanies or from its own fabrication: mills and classifying equipments (cyclones)-sampling systems- solid/liquid separation systems-agitated leach systems-reagents preparation systems and others.

  •  Merrill-Crowe zinc dust precipitation and fire refining.
  •  Adsorption/desorption with activate carbon, electrowinning and    fire refining.

TecProMIn in association with Summit Valley supplies complete plants and equipment as integral solutions for gold-silver concentration systems.


Concentration process by means of zinc dust precipitation from leaching solutions:

Once noble metals are extracted from ore by cyanide leaching, gold and silver are dissolved to form soluble cyanide complexes that are contained in the "rich solution".  In order to obtain the noble species concentration required, zinc dust is added to create a galvanic precipitation or cementation to produce gold-silver concentrate.For precipitation to provide efficient and economically worthy results, "rich solution" must be previously conditioned to produce gold and silver precipitation with zinc dust.  This conditioning is achieved by extracting suspended solids (clarification) and dissolved oxygen (deaeration); once precipitation is accomplished, the noble metals-bearing concentrate is filtered and precipitates are dried by vacuum-heating in retort kilns in order to extract contaminant volatile metals such as mercury and selenium.  Dry gold-silver concentrate is obtained to be pyrometallurgically refined in order to finally produce the 99% "metal doré" for sale.TecProMin may supply complete plants and process equipments from both, represented companies and own fabrication lines.



Solutions clarifying Filter:  The main purpose of these filters is to reduce the  impurities content in the solution. Deaeration tower :  The main purpose of the deaeration tower (also known as vacuum column) is to reduce the dissolved oxygen content in the solution in order to avoid excess zinc dust consumption.


Concentration process with activated carbon:  Gold and silver already cyanide-leached generate gold and silver soluble complexes.  These complexes in the solution are concentrated by means of adsorption process with activated carbon, also known as CIP, CIL or CIC processes.  Once gold and silver are captured in the activated carbon the process is reverted (desorption) and the physical-chemical properties in the media (solution) where the carbon has been deposited are modified in order to liberate the gold-silver complexes and produce concentration of the noble species in the new solution.    Concentrate solutions are treated by electro-chemical precipitation in order to obtain solid gold-silver concentrate (cathodic mud) that is filtered, dried and vacuum heated in retort kilns to extract any volatile contaminant metals such as mercury and selenium.  Dry gold-silver concentrate is obtained to be pyro-refined in order to finally produce the 99% "metal dore" for sale.    This process is complemented by generation of activated carbon, that when liberating the adsorpted species, is acid washed and kiln heated to reactivate its properties in order to regenerate the activate sites contained in the carbon to be re-circulated into de ADR process.

TecProMin may supply complete plants and individual process equipments from both, represented companies and own fabrication lines for  this process.






Gold and Silver adsorption system with activate carbon :  This process is accomplished by producing noble metals and conditioners concentration to be recovered as metal doré.  This process may be effected in several circuits:  

Carbon in column
, CIC, also known as carbon in solution CIS, has two types of configuration : Cascade or vertical CIC.

Carbon in leach
:  Process in which carbon is added to leaching tanks to adsorpt gold as soon as gold is dissolved in leaching stage (pregrobbing).

Carbon in pulp
, CIP: Process by which gold uptake is obtained from already leached pulp in a CIP adsorption circuit.

Elution column : it is used to elute mineral.  The elution column function is to transfer the gold contained in carbon and concentrate into a reduced volume solution.  During this stage the physical-chemical properties fo the solution are modified to effect the gold desorption in carbon for its subsequent transfer to the solution.

Acid washing column : Equipment used to treat the activated carbon with acid to eliminate the carbonates deposited in the previous processes.   Carbon contained in this column is isolated; hydrochloric acid is recirculated to dilute these salts.   Afterwards, carbon is sent to regeneration stage.

Electrowinning cells : The cell operates in close circuit with the elution column.  Its function is to deposit gold and silver on the cathodes as metal (cathodic mud) by forming a concentrate to be refined as "metal doré".

Activated Carbon regeneration kiln : This kiln i designed to reactivate the active sites in the activated carbon at temperatures near  650 ºC and by these physical-chemical conditions provide the carbon with the required activity for ADR process.



Drying - Retorting - Flux Addition - Redining

Concentrates pyro-refining :  Concentrates or precipitates from "Zinc Precipitation" or "Activated Carbon Adsorption" processes must be transformed into commercial products such as metal doré.   The presence of contaminant elements such as mercury, selenium or arsenic is very common, however these elements must be removed from concentrates in a controlled form before pyro-refining in order to provide proper care to operations personnel health and the enviroment.  This process is accomplished by heating the concentrate at the contaminants boiling points.   Treatment is vacuum made in order to reduce the boiling point and confine any gases that may be produced in the system.  Finally, concentrates are mixed with flux and refined in fission kilns to eliminate any impurities and produce the commercial doré bars (99% gold + silver).

Mercury extraction retort kiln :  This equipment is designed to remove volatile metals, i.e. mercury that boils at 356 ºC and transforms into gas.  This process reduces mercury content in a 99%.

Flux  mixing system : This equipment must mix flux with dry gold and silver  concentrate and feed the mixture to a refining  kiln.

Pyro-refining : it comprises a fusion kiln for concetrate flux mixture to obtain the final metal doré product.  Equipments  available for this  process are : fusion kiln, contaminants intake and extraction systems, different elements such as doré molds, slag cones and slag processing equipments.

Mineral Stats Inc.   P.O.Box 151057 Lakewood, CO 80215-9057 U.S.A.   t+1.720.789.8988 f+1.720.506.5204