| Abstract Scope |
Thermal routes to produce primary magnesium metal are generally demarcated with lower capital costs. However, the range of operational costs are high depending on reduction reactor efficiencies and configuration, labor intensity, and the cost of reductant. Choosing a reductant material can be a challenge in terms of logistics, supply security, cost, and technical performance. Presented is an assessment of possible reductant materials and the interplay between heat of reaction, reactor and condenser design, byproducts, and the behavior and role of impurities. On one end of the reductant spectrum is the reaction of carbon and magnesia, generating exclusively a byproduct gas, along with the product magnesium metal, and virtually no solid residue. Conversely, the reaction between calcined dolomite and ferrosilicon generates virtually no byproduct gas and nearly 6x more mass of calcium silicates than magnesium metal. These chemistries share engineering challenges that center on the method of recovery of products. |