They ♥ DME, Yeah Yeah Yeah: NREL, Enerkem Advance BIO-DME to Commercialization
by Jim Lane (Biofuels Digest) Poor DME. it burns like natural gas, handles like LPG, powers like diesel, and it’s as well-known as a good place for sewing machine repair in Burundi.
San Diego-based Oberon Fuels has been the one consistent champion on the “what are we doing about energy security?” circuit. It’s the drop-in that gets dropped out, and for no set of good reasons. NREL’s been a champion, Volvo’s been backing it without blinking, and Enerkem too — but they each have such as basket of projects and ‘we’re-working-on-its that DME rarely gets its day in the sun.
It might as well decode it, DME that is, as Despite Massive Evidence, Doubt Market Enthusiasm. As Robert Rapier observed in the Digest in 2013, “Methanol can be converted into di-methyl-ether, which gets around methanol’s toxicity and corrosivity issues. DME can be used as fuel in either a gasoline or a diesel engine, which makes the potential market huge. DME is a gas at room temperature, but compresses to a liquid under mild pressures.”
But from Washington, a booster. The U.S. Department of Energy announced nearly $16 million in funding through the Technology Commercialization Fund to help move technologies from DOE’s National Laboratories to the marketplace. Overall 54 projects at 12 national labs involving 52 private-sector partners were selected for support.
The first trend — there’s precious little across the bioenergy spectrum. Three projects for solid oxide fuel cells received support, which Nissan’s recent announce on ethanol SOFCs makes relevant. There was a carbon capture project from Oak Ridge – good for algae. And, hydrogen was the focus in a relatively massive $431,995 award to Lawrence Livermore for its Cryo-Compressed Hydrogen Tank Technology.
But there’s DME, lonely DME. All by its onesey. But it is among the biggest plums of all, $740,000 for an NREL project for Scaled Production Of High Octane Biofuel From Biomass-Derived Dimethyl Ether,. That’s in partnership with Enerkem.
Let’s take a look at DME fuel.
If you can imagine an 177-page love letter, but written in the form of process description, diagrams and High Technoeconomicese, that’s this one.
Process Design and Economics for the Conversion of Lignocellulosic Biomass to Hydrocarbons via Indirect Liquefaction: Thermochemical Research Pathway to High-Octane Gasoline Blendstock Through Methanol/Dimethyl Ether Intermediates
A cautionary note
Before we break out the bubbbly, cnsider these sober words from Zhihong Yuan and Mario R. Eden of Auburn University, together with Rafiqul Gani at the Technical University of Denmark, writing in I&EC Research, here.
Although the importance of hydrogenation of CO2 to CH4 has been emphasized in several reviews and perspectives, the current low natural gas price and the high capital/operating cost of the methanation process prohibits the thermodynamically favorable hydrogenation of CO2 from being implemented economically on a large scale. Using an optimiztic estimation, where the selectivity and conversion rate of the methanation catalyst is assumed as 100% and 50% and the renewable H2 production cost is assumed as 2 US$/kg of H2, producing 1 kg of methane will cost at least 2 US$ for the required H2. Clearly, producing high-volume-low-value liquid fuels and high-value-low-volume chemicals from the hydrogenation of CO2 may offer more economical benefit. Nevertheless, no matter which production route will be adopted, two simple principles should be kept in mind when deciding on the products and designing the process for CO2 conversion: using more energy to produce a lower energy content material makes no sense; and the CO2 emissions from the entire conversion process must be less than the amount of converted CO2.
But the authors are not completely pessimistic. They add:
Compared with the CO2-derived methanol synthesis process MegaMethanol, under similar conditions, the CO2-derived DME synthesis process MegaDME shows lower productivities, but also lower byproduct contents.(181) Furthermore, this DME synthesis process is ready for large-scale implementation and therefore provides a promising alternative for large-scale CO2conversion.
Two Multi-Slide Guides
Two Key Reports
Here’s the skinny from California on how they see DME shaping up: California Dimethyl Ether Multimedia Evaluation: Final Tier I Report
From Oak Ridge National Laboratory, SAE and Volvo:Emissions and Performance Benchmarking of a Prototype Dimethyl Ether-Fueled Heavy-Duty Truck (PDF)