"CLEAN" Magnesium Silicothermic Process offers high efficiency, low cost

Silicothermic magnesium technology was initially developed in the early 1940’s by Dr. Lloyd Pidgeon.  

                             2CaO.MgO  +   Si  =  2 Mg(g) +  2CaO.SiO2 

Dominion Magnesium opened the world's first Pidgeon Process plant at Haley, Ontario Canada in 1941. The plant was subsequently operated by Timminco Ltd producing the world’s highest purity 99.98% Mg for specialized applications until its closure in 2008. 

The Pidgeon Process suffers from its reliance on small diameter, high alloy retorts operating under high vacuum at 1200C. Since each retort has a Mg production capacity of only ~ 75 kg per day, commercial level production requires hundreds if not thousands of small-scale vacuum retorts clustered in fossil fuel fired furnaces which leads to a highly labour & maintenance intensive operation. By the early 1990's, silicothermic magnesium production had been largely eclipsed by electrolytic technology which produced over 85% of the world’s commercial grade magnesium metal.

The Chinese version of the Pidgeon Process was developed using coal based fossil fuels in the late 1990's. In doing so, Chinese producers brought magnesium technology back some 60 plus years to a highly polluting, energy and labour-intensive version of the Pidgeon process. Even though the Chinese Pidgeon Process operates at much lower productivity, & raw material utilization efficiency than the traditional Pidgeon Process commercialized in Canada, cheap labour, abundant low cost raw materials, lax pollution regulations & a low CAPEX, enabled Chinese magnesium producers to capture over 80% of world production within a few short years.  

Tech Magnesium's Clean Process represents high efficiency, low cost silicothermic technology that has a carbon footprint that is about 3 times lower than the average Chinese Pidgeon Process plant. 

Tech Magnesium’s CLEAN Process is an adaptation of its ULTRA CLEAN aluminothermic technology to silicothermic magnesium production with calcined dolomite (CaO.MgO):

            2CaO.MgO  +   Si =  2 Mg(g) +  2CaO.SiO2 

The excessive carbon footprint and low raw materials & energy utilization efficiency of the Chinese Pidgeon Process are increasingly out-of-step with today’s focus on realizing net-zero emission targets.

The CLEAN Process addresses these limitations by utilizing electricity, calcined dolomite and FeSi  to produce high purity magnesium metal in a proprietary high efficiency, low cost continuous Silicothermic Reactor.

Proof of the CLEAN Process concept: was established by rigorous thermodynamic modelling conducted by Professor Arthur Pelton, Polytechnique Montreal – an internationally recognized metallurgical thermodynamics expert & co-developer of industry leading FactSage thermodynamic modelling software. Pelton’s thermodynamic model was confirmed by bench scale experimental test work carried out at Process Research ORTECH, Mississauga, Ontario Canada. 

Using Pelton’s fundamental modelling & Process Research ORTECH’s test work results, Tech Magnesium applied its extensive metallurgical industrial processing expertise to develop high efficiency, low cost, clean, patent pending silicothermic magnesium production technology.

Maximize Raw Material Utilization Efficiency to lower material costs, reduce the amount of by-product 2CaO.SiO2 & lower energy: the process' high heat & mass transfer rates are designed to enable highly efficient reduction of  CaO.MgO to commercial grade purity magnesium metal with an industry leading Silicon Efficiency of 91.9% & a Magnesium Yield of 90.4%.

Low Carbon Footprint: the carbon footprint of the CLEAN Process has been determined by Process Research ORTECH as 9.1 kg CO2 per kg Mg metal when using renewable electricity for both Mg & FeSi production and CaO.MgO produced from raw dolomite in a natural gas fired rotary kiln.  As such, the Tech Mag CLEAN Process carbon footprint is significantly lower than the 21.8 kg CO2 per kg Mg average for Chinese Pidgeon plants, the ~15 kg CO2 per kg Mg for existing electrolytic plants and is less than the 11.7 kg CO2 per kg Aluminum  world average for primary & recycled aluminum production. Further reduction in the process’ carbon footprint is expected by employing technology to recover magnesium condenser waste heat to produce steam or electricity. 

Innovative Electrical Process Reactor Design Replaces Low Productivity, Fossil Fuel Fired Retort Production: Tech Magnesium has adapted industrially  proven electric furnace technology into a novel Process Reactor specifically designed for continuous, efficient magnesium production. This proprietary reactor provides the following advantages:

• facilitates highly productive continuous magnesium production.
• replaces fossil fuels with clean renewable electricity, significantly reducing the process’ carbon footprint.
• provides an atmospherically tight design critical for efficient magnesium metal recovery.
• facilitates exceptionally high mass & heat transfer rates which are the efficiency limiting constraints for the Pidgeon magnesium process.
• facilitates atmospheric magnesium production pressures, eliminating the need for a vacuum.
• facilitates condensation of magnesium process gas to pure molten magnesium using Tech Magnesium’s proprietary isothermal condenser. Molten magnesium condensation is important to increase Mg yield, reduce energy consumption, lower production costs and facilitate efficient molten metal transfer methods.

Low, Competitive OPEX: Tech Mag CLEAN Process produces Mg at a cost lower than both Chinese & Electrolytic magnesium production and is on a par with the world average cost to produce aluminum, once adjusted for density differences between Mg & Al. 

Low CAPEX per ton: the Tech Mag CLEAN Process plant can be built in 5,000 MT modules in tune with market demand.  Most importantly, its capital cost is       ~ 3.5 times lower than the capital cost of a typical Mg electrolytic plant thereby maximizing ROI.