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Extractive metallurgy has used free or combined sulfur as both the raw material and the energy material in carrying out economical manufacture of several metals in millions of tons per year quantities over the past century. This has controlled carbon emissions in an unintentional fashion and out of necessity as the ores in many cases have been sulfides to start with. And the benefits of heat generation by the sulfides reacting with oxygen in the process steps have avoided the use of carbon as a fuel in providing the reaction temperatures. In this article, we will show the inherent benefits of “thiometallurgy,” which uses sulfur in the extraction of metals in alleviating CO2 and water vapor–greenhouse gas (GHG) emissions, as well as its ability to provide a cost-effective energy material solution. Such solutions are not only applicable to existing base metal production but, as the authors will show, also are applicable to newer processes in the production of other metals and chemicals, such as alkaline earth metals, titanium, and to an extent aluminum in an indirect fashion. Iron ores can also be treated with thiometallurgy to meet the ULCOS criterion of ultra-low carbon dioxide steel being studied in Europe. The concept of generating “thiopower” as an alternative energy approach is also introduced by the authors.

Common fuels—whether they are simple hydrocarbons or oxygenated hydrocarbons or carbohydrates—can be economically produced from the respective oxides of carbon and hydrogen by simple chemical reductions. These reactions are efficiently carried out by applying fundamentals of the reduction process.

An innovative concept for one of the lowest-cost carbon dioxide capture methods from power plants and other carbon-dioxide-emitting facilities is provided here. The concept is to use a novel electro-thermo-chemical regeneration approach which will generate a product solution containing hydroxyl ions for absorbing the flue gas CO2. This may work with existing flue gas desulfurizing equipment to minimize the cost of carbon capture. The process involves the use of low-cost make-up reagents which are capable of providing credits for partial mineralization of CO2, thus offsetting some of the costs for carbon capture and sequestration. The process presents the possibility of making this a low-cost on-site mineralization with cost offsets.

The role of minerals in biomass formation is understood only to a limited extent. When the term “photosynthesis—CO2 and H2O reduction of sugars, using solar energy”—is used, one normally thinks of chlorophyll as a compound containing magnesium. Alkali and alkaline earth metals present in leaf cells in the form of ions are equally essential in this solar energy bioconversion coupled with nitrogen fixation. Application of some of these principles can lead to artificial carbon-neutral processes on an industrial scale close to the concentrated CO2 emission sources.

The analysis of recently announced battery packs for plug-in hybrid electric vehicles (PHEV) shows that the design of the series-parallel combinations is being over-complicated. The proven energy densities of lithium-ion cells from about 200 Wh/kg are being reduced to 90 Wh/kg. The majority of the weight increase seems to be for thermal management. Simpler battery pack designs based on electro-refining pot rooms using self-contained rectangular lithium-ion cells with air cooling inside of die-cast magnesium cell tanks would help avoid hauling dead weight in PHEV by providing considerable weight reduction.

As an alternative to fossil fuels, solar energy can help minimize global warming triatomic gas emissions (CO2 and H2O) when used in metallurgical processes. This paper reviews the technical development in this field from the first patents filed in the late 1800s to present-day pilot work of solar zinc production.

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 usually use less energy than the primary production processes. The control of CO 2 and other greenEnergy Conservation, CO2, and Other Greenhouse Gas Reduction