Highly concentrated sunlight is capable of supplying ample process heat for chemical reactions at very high temperatures. It will be used in two activities during this project. The first process produces an aluminum-silicon alloy from direct carbothermal reduction of any alumina-silica containing ore. The product is an aluminum-silicon alloy that can be either used as an alloy, or further refined via a fractional crystallization and electrolytic separation process developed in the late 1970's. The main challenge of this project will be to develop a reactor suitable to utilize solar process heat, and a receiver to contain the reactor and direct incident solar flux. This project touches two of the most fundamental needs of the aluminum industry: the need to reduce industry-wide dependence on the Hall-Heroult process, and the need to economically employ other forms of aluminum ore. It holds the promise of realizing one of the most sought-after goals of aluminum industry research since discovery of the metal: direct reduction from ore to alloy or metal without relying on expensive electrically-supplied process heat. It is not only the high cost of electricity that is making the United States lose its international competitiveness in primary aluminum manufacture. Risk is imposed by fluctuating costs and fear of increasing energy costs. Benefits from commercialization of a solar direct reduction process also include the possibility of locating smelting facilities at the site of ore deposits in some cases. Use of high-temperature solar process heat will drastically reduce emissions from the aluminum manufacturing process.
