A new breakthrough thermal magnesium process has been developed by Tech Magnesium’s Dr. Douglas J. Zuliani who holds a Ph.D. in Metallurgical Engineering from the University of Toronto. Dr. Zuliani worked in senior management for 16 years at Timminco Ltd., a former world leader in high purity magnesium metal production using the Pidgeon Process, which was invented in the 1940s by Dr. Lloyd Montgomery Pidgeon of the Canadian National Research Council. The Pidgeon Process is still the most widely used magnesium production process in the world.
The Zuliani Process utilizes electricity to produce magnesium metal from calcined dolomite and FeSi (ferrosilicon). It has been designed to specifically address the main constraints that have unfavorably impacted operating cost, productivity and GHG emissions with all known thermal magnesium processes to date, including the Pidgeon Process.
The objectives of the Zuliani Process are:
* To maintain sustainable profitability by realizing a 20-30% direct production cost advantage of over existing magnesium producers in China;
* To spur market growth by achieving a direct production cost that is competitive with aluminum (~< 1.3 x Al Cost). Industry estimates indicate electricity represents ~1/3 of the production cost of aluminum. Assuming an average rate of about $0.04 per kWh and power consumptions of 12,500-15,000 kWh per tonne, under normal circumstances aluminum production costs can be expected to range between ~$1500 – $1800 per tonne. Under these assumptions the target competitive magnesium production cost should range between ~ $1,950 – $2,340 per tonne (1.3 x Al cost);
* To achieve a Life Cycle Assessment competitive with aluminum.
To date, independent thermodynamic modeling and bench scale experimentation have been conducted to verify the chemical and raw materials utilization efficiencies of the Zuliani Process.
Thermodynamic Modeling Results
In 2007 Dr. Arthur Pelton of THERMFACT Ltd. and a Professor at Ecole Polytechnique in Montreal, Quebec was contracted to develop a thermodynamic model of the Zuliani Process using the FactSage integrated thermodynamic databank system which calculates the conditions for multiphase, multi-component equilibria in complex gas-slag-metal systems.
Dr. Pelton’s analysis and confidential report were issued in September 2007 with the following main findings:
1. The Zuliani Process is capable of producing magnesium vapor at atmospheric pressure in the desired temperature range of 1550-1650oC. As such the Zuliani Process will not require the use of a vacuum, which is required in other thermal methods.
2. The report confirms that unlike other thermal processes that produce crude solid magnesium, which requires melting before refining and casting into commercial grades, molten magnesium condensation is feasible with the Zuliani Process. Using dolomite from Manitoba, Canada as a sample feedstock, an assessment of the composition of the magnesium vapor phase confirmed that this dolomite is of sufficient purity to produce better than 99.8% commercial grade magnesium metal.
3. The report confirms the boundary conditions where the Zuliani Process will operate at a high thermodynamic efficiency. Although the study focused principally on process thermodynamics, the report also indicates that it is expected that the PROCESS will demonstrate excellent kinetics for producing magnesium compared to other thermal magnesium processes using dolomite and FeSi.
Bench Scale Experimental Results
In 2009, Process Research ORTECH Inc. (ORTECH) of Mississauga, Canada, an independent pilot lab with recognized metallurgical expertise, was retained to conduct bench scale testing of the Zuliani Process to extract magnesium metal from dolomite and confirm the process thermodynamics and kinetics.
The ORTECH bench scale tests were carried out in three phases with final results reported in September 2011.
The following was concluded based on a constructed mass balance derived from ORTECH’s bench scale experiments:
1. The Zuliani Process produces magnesium metal vapor at 1 atmosphere in the desired temperature range. Atmospheric production will avoid the need for using costly and complex vacuum systems and is an important prerequisite for molten magnesium condensation.
2. The efficiency and chemical effects of varying FeSi grade in the range between 30-75% were consistent with that previously predicted by Dr. Pelton’s FactSage thermodynamic model.
3. There is exceptional agreement between the experimental mass balance developed using the measured initial raw material chemistry, measured raw material weights and measured final slag weight and chemistry as determined in the ORTECH tests and Dr. Pelton’s thermodynamic model.
In a subsequent independent analysis of the results, Dr. Pelton reviewed and verified that there is excellent agreement between the ORTECH experimental mass balance and the FactSage thermodynamic modeling predictions. This excellent agreement indicates that the high efficiencies predicted by the thermodynamic model are confirmed by actual experimentation. The results confirm that the Zuliani Process will achieve significant efficiency improvements over all other commercial thermal production methods currently in commercial use.