Fuat Celik, Eric D. Larson and Robert H. Williams
Princeton Environmental Institute, Princeton University, Princeton, NJ, 08544 USA
We present energy and carbon balances and cost estimates based on detailed Aspen Plus process simulations for five plant designs to co-produce dimethyl ether (DME) and electricity from coal. Four of the designs include capture of CO2 for long-term underground storage. We also illustrate the potential DME offers for reducing emissions by facilitating a shift to more energy-efficient vehicles."
a US Department of Energy, National Energy Technology Laboratory, PO Box 10940, Pittsburgh, PA 15236, USA
b Parsons Infrastructure and Technology Group, PO Box 18288, Pittsburgh, PA 15236, USA
Abstract
The gasification of carbon-based solid (i.e., coal - JtM) and liquid materials has been around for nearly two hundred years and was used extensively for the production of town gas in the latter part of the nineteenth and twentieth centuries. Although this application has all but vanished, other applications have evolved, thus continuing gasification's important role as a commercial technology. Numerous advancements have been made since its introduction, leading to a more cost-competitive, thermally efficient, and environmentally friendly technology. However, as deregulation of the power industry continues and as increased environmental pressures are placed on industry, opportunities for further technological advances and expanded applications to meet these challenges will be created. In addition, these changes will likely restructure the technology and ownership objectives, placing premiums on efficiency, environmental acceptability, and the ability to utilize multiple feedstocks and produce multiple products. In the twentieth century, gasification will be the heart of a new generation of energy plants, possessing both feedstock and product flexibility, near-zero emission of pollutants, high thermal efficiency and capture of carbon dioxide, and low feedstock and operating and maintenance (O&M) costs."
So, let's recap the highlights: Gasification of coal, for liquid fuel manufacture and other useful purposes, is "cost-competitive, ... efficient, and environmentally friendly" with "near-zero ... pollutants".
Eric D. Larson(a) and Ren Tingjin(b)
a Princeton Environmental Institute, Princeton University Guyot Hall, Washington Road, Princeton, NJ 08544-1003, USA.
b Department of Thermal Engineering, Tsinghua University, 100084 Beijing, China
"Troy A. Semelsbergera, b, , Rodney L. Borupa and Howard L. Greeneb
aMaterials Science & Technology Division, Los Alamos National Laboratory, P.O. Box 1663, Mail Stop J579, Los Alamos, NM 87545, USA
bDepartment of Chemical Engineering, Case Western Reserve University, Cleveland, OH 44106-7217, USA
Abstract
With ever growing concerns on environmental pollution, energy security, and future oil supplies, the global community is seeking non-petroleum based alternative fuels, along with more advanced energy technologies (e.g., fuel cells) to increase the efficiency of energy use. The most promising alternative fuel will be the fuel that has the greatest impact on society. The major impact areas include well-to-wheel greenhouse gas emissions, non-petroleum feed stocks, well-to-wheel efficiencies, fuel versatility, infrastructure, availability, economics, and safety. Compared to some of the other leading alternative fuel candidates (i.e., methane, methanol, ethanol, and Fischer–Tropsch fuels), dimethyl ether appears to have the largest potential impact on society, and should be considered as the fuel of choice for eliminating the dependency on petroleum.
DME can be used as a clean high-efficiency compression ignition fuel with reduced NOx, SOx, and particulate matter, it can be efficiently reformed to hydrogen at low temperatures, and does not have large issues with toxicity, production, infrastructure, and transportation as do various other fuels. The literature relevant to DME use is reviewed and summarized to demonstrate the viability of DME as an alternative fuel."
You will note, above, that DME is said to be preferable even to Fischer-Tropsch (FT) fuels (derived from coal). Perhaps. As we've documented, FT coal fuels themselves offer many advantages over current petroleum liquids. Either way, though, the clear evidence is that we can make liquid fuels that are beneficial both to our economy and to our environment from our abundant reserves of coal.