Some metal ores are converted to metals using energy other than carbon-based fuels—such as electricity. CO2, and H2O—which are similar to metal ores (oxides, sulphides etc.) and can be modified to non-global-warming forms by techniques well known to extractive metallurgists.
It is in these layman terms that N R. Neelameggham, introduced his excellent summary of the Transactions of the (US) Materials Society - TMS Symposium 2008 dedicated to CO2 reduction Technologies.
"When converting minerals into metals, energy is consumed. Even though energy in various forms can be used in achieving this conversion, or reduction, typically a reductant that can carry the anion of the mineral away from the desired element is used. The potential for economic production of common fuels from the respective oxides of carbon (CO2) and hydrogen(H20) by simple chemical reductions was the inspiration for the CO2 Reduction Metallurgy Symposium at the TMS 2008 Annual Meeting."
Several clear statements emerge :
1. The world needs fuels in all three states of matter: solid, liquid, and gaseous. Naturally available solar, wind, and hydro-energy (marine, wave) can be converted into the mobile forms of fuel(nb. position on the Venn Diag. above) by using carbon dioxide and water. When such conversions can be affordably achieved, perhaps one cause of global warming— carbon emissions—will be minimized.
2. Most of the gaseous emissions from the use of fuels are emitted at temperatures higher than ambient temperature. This mass of gases, when mixed with ambient atmosphere, increases the atmospheric air mass temperature. Present-day fuels release both CO2 and H2O, along with hot air, in their exhaust. Of these, the non-condensable CO2 (under atmospheric conditions) continues to increase and is easily measured. In addition, these tri-atomic molecules participate in the radiative heat transfer in the atmosphere [whereby the balance is heat-warming compared to a H20 base-line, hence the label "Greenhouse gas"-JA].
3. Unless another cooling medium can dissipate this thermal emission by some other mechanism, global warming will persist. We can only minimize the rate of global warming and not eliminate it as long as the energy conversion from one form to another happens with certain uncontrolled emission of heat. This necessitates the reduction of thermal emission and its constituents. Minimizing the temperature of gaseous emissions by simple methods will go a long way toward minimizing the rate of increase in atmospheric temperatures.
4. Extractive metallurgists can reduce any oxide compound to its elemental form. Examples of this are the making of iron from iron oxides, aluminum from aluminum oxides, and hydrogen from hydrogen oxide (or water). Carbon dioxide is just like any other oxide and can be reduced to its respective elements by applied energy, a process that could minimize the amount of CO2 released in the air and result in improved fuel self sufficiency.
The symposium was divided into three major sessions [pdf link]:
introduced by a Keynote address by Meyer Steinberg, ex-Brookhaven National Laboratory, co-author with M. Halmann, of a detailed treatise Greenhouse Gas Carbon Dioxide Mitigation: Science and Technology based on more than 30 years each of expertise in this field
M. Steinberg’s review covered the principles of removal and recovery from power plant stacks, the oceanographic and geological disposal of CO2, and the conversion of CO2 to gaseous and liquid transportation fuels.
This symposium is the first of its kind in applying extractive metallurgy techniques.
It is complimentary to several international conferences on CO2 utilization. There have been eight such symposia so far, the last of which was held in Oslo, Norway in 2005, which by chance, allows me to introduce CO2 uses and eventually the Carbon Economy and Industries[pdf conf outline-link] as referenced in the Venn Diagramme above ),2 and minor symposia on the subject by the American Chemical Society, American Institute of Chemical Engineers, Electrochemical Society, etc., in promoting pertinent know-how in solving these global concerns.
Approaches to CO2 emission reductions in metal production by improved energy efficiency in life-cycle fuel use, (cf. recent posts on LCA-Life Cycle Analysis 1. previous post and 2. JM Pearce's et al approach for example) , reduction in carbonate based flux/raw material usage, and thermodynamically feasible reactions leading to lower emissions are all part of this program.
The topics discussed give useful pointers to researchers, project managers and business innovators.
UK Extractive Metallurgy Resource cf Journal Cover
Warning- It is well worth periodically reading-up and checking-out Climate Change and GHG effects at the "Source"
1. Most reputed blog: RealClimate ™
2. The World Authority UN - IPCC
3. My Blogs eg Conversations give various links as I build my knowledge base.
PS:Ours is a very energy intensive industry. I still believe that current official policy, strong recommendations-EU directives... to sink CO2 must not be hindered by our current professional tastes. Such policy choices are made taking into account multiple criterion: people (are still people), societal, technological, powerful lobbies... They must be taken seriously-more seriously than at present. LCA appears to be the only objective, correct, way forward in all our professional activities. Indeed it ought to start in the Lab. and in University education irrespective of you religous faith, or not:
"remember your creator
or if you prefer more order
the atoms and molecules
you are now made of
in the days of your youth!"
Comments, suggestions, information, or question welcome.