Energy conservation, CO2, and other greenhouse gas reduction

To read more about them, turn to page 10. To join TMS, visit www.tms.org/Society/Membership.aspx. Energy conservation as well as CO 2 and other greenhouse gas reduction present long-term challenges to our society, and the problems are exacerbated by the rapid consumption of materials and energy and signifi cant emissions of greenhouse gas and toxic gases. By 2050 the world’s oil production will be half of what it is today. Capping CO 2 in the atmosphere at 450 ppmv will require its sequestration. Metallurgical industries and transportation systems are the main energy users and the main producers of greenhouse gas. Production of renewable energy and saving energy in metallurgical processing are two keys to energy conservation. As an example, solar cell energy is a well known renewable energy and it is claimed as a green energy by most people. However, if the feedstock, especially for multi-crystalline silicon, is included, solar cell energy is not a green energy since during the production of the high purity silicon, signifi cant energy is consumed, much CO 2 is emitted, and several non-green processes, such as strong acid leaching, are included. Furthermore, during the wafer slicing process of a high-purity silicon ingot, over 50% becomes slurry wastes and there are no successful industrial processes to recycle these valuable wastes. In order to save energy, traditional industrial processes should be optimized. Furthermore, reuse, recycling, and recovery of metals and materials should be emphasized since these processes usua...