M. Halmann and A. Steinfeld
Department of Environmental Sciences and Energy Research, Weizmann Institute of Science, 76100 Rehovot, Israel
Department of Mechanical and Process Engineering, ETH-Swiss Federal Institute of Technology, 8092 Zurich, Switzerland
The cement and lime industries are major contributors to the anthropogenic CO2 emissions to the atmosphere. By combining the CO2-releasing calcination of CaCO3 with the CO2-consuming dry-reforming of CH4, and by further combining these endothermic reactions with the exothermic partial oxidation of CH4, a single thermo-neutral process can be designed for co-producing CaO and syngas in an authothermal reactor. Syngas can be further processed to H2, methanol, or Fischer–Tropsch chemicals. The conditions for thermo-neutrality are determined by thermo chemical equilibrium calculations. Such combined processes could achieve considerable CO2 emission avoidance as well as fuel saving relative to the conventional production of CaO and syngas. A preliminary evaluation indicates favorable economics for the co-production of CaO and hydrogen or methanol from CaCO3+O2+H2O and natural gas (NG) or coal."
Again: The "CH4" for "CO2-consuming" can be obtained via coal gasification or Sabatier CO2 recycling.
We submit that, if we have "H2", we can further hydrogenate crude coal liquids into more entertaining products.
But, aside from that, combining "CH4" with "CO2" yields "Fischer–Tropsch chemicals", which, if you've been following our posts, you know to include liquids that can be refined into diesel and gasoline.
And, these authors specify that this "thermo-neutral" technology does produce "methanol", which ExxonMobil can, through their "MTG(r)" process, convert into gasoline for us. It's also a good starting point for a few valuable plastics manufacturing processes, as well.
Finally, this whole scenario is presented as a solution to the CO2 emissions of the "cement and lime industries". They do need a CO2 solution as much as, or more than, coal-fired power plants do. So, this sounds like a win-win for all concerned.
Be real nice to have a "win" in Coal Country, wouldn't it?
Don't forget: In addition to fuel and fertilizer, we get more cement, too, out of it all, for those Mountain State road repairs.
These Swiss and Israeli scientists conclude with: An "evaluation indicates favorable economics for the co-production of CaO (i.e., cement) and ... methanol from ... coal."
Really: How good does it have to get?