Robert Gerhard Merker,

Freelancer, Master of mineral processing engineering

Oertenroeder Str. 21
D-35329 Gemuenden (Elpenrod)
Phone: +49 (0) 6634 / 91 88 560
Mobile: +49 (0) 173 / 53 55 828

Sourcing of Raw Materials:

all other services:
1. Education
1976 – 1981 Mining University Freiberg/ Germany (Bergakademie)
  • studies of mineral processing / mechanical processing engineering, graduation as a master of engineering (Dipl.-Ing.), engineers degree project: china clay processing, diploma thesis: flotation of poor tin ores.
1991 – 1992 College of Chemistry Fresenius Wiesbaden (Chemieschule Fresenius)
  • professional training in industrial environmental pollution control, contaminated sites management, hazardous materials and waste management.
2. Professional carrier
1981 - 1990 Mineral Raw Materials Consulting Dresden GmbH, (geological industry) research associate and project manager,
  • project development, exploration of mineral deposits, process and product development, basic engineering, feasibility study rare earths (RE) ores etc.
1992 - 1995 B.U.S Environmental Services (Berzelius- Umwelt-Service AG) (plants of processing and recycling of residues from the metallurgical industry) Project engineer and project manager,
  • pilot tests, process development, engineering, plant construction, application engineering of secondary raw materials, product and market development
1996 - 2003 Aluminum Salt Slag Treatment Hanover und Luenen (ALSA GmbH)(treatment and recycling plants of salt slags from Aluminium smelters) Project manager, since 1997 head of Alumina sales and process development,
  • build-up of a secondary Alumina market in Germany and Central Europe, application engineering, product development,
  • process development, planning, construction and commissioning of processing plants in Germany, Norway and Canada
2004 - 2005 Recyclage d’Aluminium Québec Inc. Becancour/ Canada, later on ALSA Canada(Al-smelters and salt slag treatment) Consultant and manager of marketing and product development,
  • commissioning and de-bottlenecking of a Salt Slag processing facility
  • product and market development for Alumina in North America
2005 - 2009 Aluminum Salt Slag Treatment Hanover, Luenen and Toeging, (ALSA GmbH, now BEFESA Salzschlacke), in Germany head of application engineering and product development,
  • expansion of an Alumina market towards South Germany and Southeast Europe
  • green field project site evaluation, commissioning and de-bottlenecking of processing facilities
  • Project management, product and process development
from 2010 on Freelancer (R. Gerhard Merker – mineral processing engineer)
  • consulting for raw material producer and trader, recycling and processing facilities, etc.
  • sourcing and supply of Alumina, mill scale, Iron ore, micro silica, Silicon carbide, Silicon, Iron sulphate, fly ash etc.
  • raw material sourcing and consulting for portland and special cement kilns, flux blenders, mineral wool facilities, etc.
  • market development and studies about secondary raw materials like Alumina, Manesia, dross etc.
  • process deveolpment and engineering for processing respectively recycling of salt slags, Alumina, Silicon by-products, Rare Earthes, Tin and Gold ores etc.
  • consulting of REACH- and CLP-procedures, development of a product status
  • consultant for processing tests of rare earth exploration projects among
3. International experience
Vietnam: 1984 - 1988 technical consulting, ore reserve evaluation, pilot tests, planning of a green field rare earth mining project
Belgium, France, Scandinavia, Poland, Hungary, Czech, Austria, Sweden: Seit 1994 acquisition / customer care/ application engineering (cement kilns, mineral wool, steel mills)
Norway: 2003 permit application, plant site evaluation, planning of a brown field project
Brazil: 2003 Aluminium recycling seminar in Sao Paolo,
USA / Kanada: 2000 - 2008 project development, plant planning, site evaluation, consulting, commissioning, product and market development,
2012/2013: consultant of metallurgical tests of a rare earth exploration project

middle East: 2011 consulting of Aluminium dross processors
4. Raw materials and processes
Geological exploration: Rare Earthes ores, Feldspar, Quartz, Bentonite,
Raw materials and commodities: Quartz, Feldspar, Bentonite, Bastnaesite and Monazite RE ores, Col-Tan ores, Heavy Mineral sands, Baryte, Talcum, Tin ores, Gold, China clay, Alumina, Aluminiumhydroxide, Aluminium Metal, Aluminium dross, Silicon,SiC, Arc furnaces steel mill dust, Waelzkiln slag, Foundry sand, Al- and Mg-Salt Slags and cakes, Bypass dust from cement kilns, Potash
Processes and techniques:
  • Flotation of Bastnaesite, Monazite, Fluorite, Baryte, Mica, Cassiterite, Potash etc.;
  • Magnetic separation and purifying of Ilmenite, Mica, Bastnaesite, Aluminium oxide, Aluminum
  • Electrostatic separation of Silicon and Heavy minerals;
  • Eddy current separation of metals like Magnesium and Aluminum,
  • Gravity separation of Tin and Col-Tan minerals;
  • Wet and dry processing of Al- and Mg-salt slags;
  • Processing of various ores, Feldspar, Aluminium oxide, China clay;
  • Classifying of Aluminium oxide, metals, Salt slags, ore slurries, China clay, etc.;
  • Autogenous comminution of Salt slags;
  • Screening of Aluminiumoxide, Aluminium hydroxide, Feldspar;
  • Calcining of ceramic products, secondary Alumina, Calcium Aluminates;
  • thermical purification and upgrading of Alumina from salt slag and dross processing;
  • Drying of Alumina, Aluminum, ore concentrates;
  • Pelletizing of Aluminium hydroxide, ceramic mixings, Steel mill dust, Bypass dust;
  • Briquetting of Stell mill dust, Aluminium hydroxide, Alumina, Silicon etc.;
  • Filtration of China clay, ore slimes, Aluminium hydroxide, Salt slag;
  • Dedusting and cleaning of dryers and calciners off-gases;
  • Melting of Alumina etc.;
  • Mechanical and pneumatical conveying of dusts, bulk materials, etc.;
  • Crystallization of Chlorides
  • Processing of Goldores
5. Planning, construction and commissioning
Ore processing: 1985 - 1989: Rare Earthes Ores of Dong Pao/Vietnam:
development of a processing technique, basic engineering, (grinding, flotation, classifying, magnetic separation, filtration, drying, acidic leaching), site evaluation, mine and facility planning, feasibility study for 40 kt/y of ore input
2012 / 2013: Rare earth ore Ashram/Eldor/Canada:
development of a flotation technique for a Monazite + Bastnaesite bearing carbonatite rare earth ore
Salt Slag processing: 1995 - 2009: operation of Best-Available-Technology Salt Slag treatment plants at Luenen 170 kt/y, Hanover 110 kt/y, Toeging 100 kt/y in Germany (crushing, milling, screening, leaching, oxide filtration, chloride crystallization, off-gas washing, fertilizer production, etc.) 1998 - 2003: process development and pilot processing tests of German, Canadian and Norwegian Salt Slags; 1997 / 1998: development, construction and commissioning of a wet milling facility (milling, screening, magnetic separation, metal drying, off-gas washing) at ALSA Luenen/ Germany, 60 kt/y Al–Salt-Slag-fines input 2001 - 2004 development, planning, commissioning of a sophisticated processing plant (wet milling, screening, magnetic separation, leaching, oxide filtration, oxide curing and drying, chloride crystallization, off-gas combustion, etc.) at RAQ Inc. in Becancour /Canada, 30 kt/y slag input capacity 2003 development, planning and permit application of a Salt Slag processing plant (crushing, wet milling, screening, filtration, leaching, crystallization etc.) at Hydro Aluminium in Karmoy /Norway, 50 kt/y capacity 2006 - 2008 construction, commissioning and de-bottlenecking of a Salt Slag processing plant (wet milling, screening, magnetic separation, leaching, oxide filtration, oxide curing and drying, crystallization, etc.) at ALSA Sued in Toeging/Germany, 100 kt/y input capacity
Pelletizing: 1994 / 1995 development, construction and commissioning of a mixing and pelletizing facility of Steel Mills Arc Furnace dust and coke breeze at B.U.S Zinkrecycling Freiberg/ Germany, 100 kt/y capacity
Press filtration: 1999 / 2000 development, construction and commissioning of a press filtration facility of secondary Alumina at ALSA GmbH Luenen/Germany, ard. 100 kt/y output capacity
Calcining: 1994: pilot tests and basic engineering of a fluidized bed calcining facility to produce high value ceramics from secondary Alumina, BUS AG 2001 / 2002: development, planning and permit of a brown field calcining project (mixing, pelletizing, rotary kiln, cooler, screening, silo storage, packaging, off-gas cleaning) to produce Calcium Aluminate at ALSA GmbH Luenen / Germany, 30 kt/y output capacity
Drying: 2003 / 2004 construction and commissioning of an Alumina drying facility (feeding system, rotary dryer, bag house filter, screening, packaging) at RAQ Inc. in Becancour/Canada, ard. 20 kt/y output capacity 2007 construction, commissioning and de-bottlencking of an Alumina drying facility (feeding system, rotary dryer, bag house filter, pneumatic conveyors, silo station) at ALSA Sued in Toeging / Germany, ard. 50.000 t/y output capacity 2007 / 2009 start-up, de-bottlenecking and ramping-up of an Alumina drying facility at ALSA GmbH in Hanover/ Germany, ard. 20 kt/y output capacity
6 . Market development, Application engineering
  • secondary Alumina for the lines of cement clinker, mineral wool, steel refining slags, refractories, building materials, filler etc.; development of a market of ard. 250 kt/y secondary Alumina in Germany, Europe and North America
  • Feldspar / Quartz products in the ceramic and glass industry;
  • waeltz-slag for the road construction
  • Silicon and SiC, by-products for the metallurgy etc.
  • Mikrosilica for construction
  • mill scale and low grade iron ores for cement kilns etc.
7. Patents, papers, references

  • ...Hartgesteine als unkonventionelle Feldspatrohstoffe..., (granitic rocks as non-conventional feldspar raw materials), Freiberger Fo.-hefte C399, 1984, S. 49-56
  • Aufschlussverfahren von Bastnäsitkonzentraten, (chemical processing technique of
    Bastnaesite ore concentrates) Patent DD 262845 A1, 31.07.1987
    link to file
  • A processing technology for heavily weathered rare earth ores ...,17th Int. Mineral Processing Congr., Dresden, 23-28 Sept. 1991, Preprints Vol. IV, pp. 321-330,
    (dito in: Erzmetall 9/91, pp 452-457),
    link to pdf
  • Geologische Situation und Aufbereitungsmöglichkeiten des Seltene Erden Erzes von Donp Pao/ Vietnam. (geology and processing of the rare earths ore of Dong Pao/Vietnam) - Erzmetall, 44(9/91): 452-457, Weinheim.link to pdf
  • Geological situation and processing possibilities of the rare earth ore of Dong Pao/ Vietnam. - In: Natural Resources and Development - a biannual collection of recent German contributions concerning the exploration and exploitation of natural resources, Vol 37, 1993: S. 7-17, Tübingen (Institut für wissenschaftliche  Zusammenarbeit).link to pdf
  • Herstellung v. Schmelzspinell …, (manufacturing of molten spinel ...), Patent DE 433 30 21, 29.09.93
  • Bodenauskleidung f. Elektrolysezellen, (bottom lining of aluminium electrolysis cells), Patent DE 197 22 788 A1, 30.05.97
  • High-Alumina Secondary Raw Materials…, Tile & Brick International, Vol. 14, No. 3, 1998, S. 2-4link to pdf
  • Hochtonerdehaltiges Pulver, Verfahren zur Herstellung und ..., (high alumina powder, procedure for its production and ...), Patent DE 100 40 582 A1, 15.08.00
  • ... Tonerderohstoff aus der Aufarbeitung von Al-Salzschlacke, (... alumina raw materials from the reclamation of aluminium salt slag), Freiberger Fo.-hefte A 864, 2001, S. 107 ff.link to pdf
  • Porosierender, erstarrungsbeschleunigter Bindemittelbaustoff-Zusatz und Verfahren zu seiner Herstellung, (porosifying and solidification-accelerating additive for binding agent building materials and procedure of producing), 15.08.2000, Patent EP 1180504, US 6593262, etc.
  • Hochtonerdehaltiger Rohstoff, Verfahren zur Herstellung und …, (high alumina raw material, procedure of producing and ...), Patent EP 144 09 37 B1, 08.01.2004,
  • GET a KIS, Congress of metallurgists (COM) Vancouver, paper 19.3., Aug. 2003,
  • Sustainable reclamation of aluminium salt slags, Vortrag auf dem “Int. Seminar of Al-recycling of ALBA”, Sao Paolo, Okt. 2003,link to pdf
  • Verfahren zur Herstellung eines halogenarmen hochtonerdehaltigen Rohstoffs, (procedure for producing a low halogen high alumina raw material), Patent DE 102006060209 B3, 18.12.2006
  • An unconventional Al2O3 alternative, Industrial Minerals, Dez. 2006, S. 67-71link to pdf
  • ALSA are developing secondary aluminas, Vortrag auf: 13th bauxite and alumina seminar Athens 06 - 07.03. 2007 link to pdf
  • News from ALSA’s secondary alumninas, paper of the 14th bauxite and alumina seminar Miami, March 2008link to pdf
  • Hochtonerdehaltiger Rohstoff und Verfahren zur Herstellung, (high alumina raw material and procedure for its production), Patentanmeldung EP 08005328.3, 20.03.08
  • About the processing of carbonatite rare earth ores; paper of the conference on processing
    and recycling at UVR-FIA Freiberg, Nov. 2012
    link to file
  • News release of the company Commerce Resource Corp. about the beneficiation of the
    Ashram REE ore, Feb. 2013 on www.commerceresources.com
    link to the pdf of CRC NR feb 13
  • About the reclamation of salt slag / salt cake / black dross (and the recycling of aluminium generally), paper of the conference on processing and recycling, UVR-FIA Freiberg, Nov 2013link to pdf of the salt slag reclamation paper
  • News Release of the Commerce Ressource Corp. web site (www.commerceresources.com) about the beneficiation of the Ashram REE ore, Dec 2013link to CRC NR pdf file dec 13
  • Use of virtual fractions for the MLA of low grade Y-bearing REE ores, paper 894 of IMPC 2016 Quebec,link to pdf 894 IMPC Y-ores
8. Presentation and list of clients