Brown Coal to Oil Direct Conversion

Image SourceLow quality brown coal can not be used under the air quality and carbon emissions regulations of many advanced countries. Yet low quality coal represents a huge stockpile of energy wealth waiting to be used, from Australia to North America, to Asia. Clever engineers and technologists are devising multiple ways of getting at the energy inside low quality coal, without emitting the pollutants. The following article describes only one approach.

Ignite Energy Resources (IER), developer of a supercritical water technology, and TRUenergy have entered into a Memorandum of Understanding (MoU) to develop a commercial demonstration plant that will apply IER’s direct coal-to-oil and upgraded dry coal process to the brown coal at TRUenergy’s Yallourn mine in Australia.

IER’s proprietary supercritical water technology (SCW) transforms low-ranked coals, including lignite, directly into higher-valued oils and cleaner coal products. IER’s Hydrothermal Reactor (HTR) technology depolymerizes lignite and biomass by using SCW to cut it directly into oils and upgraded cleaner coal products—i.e., not via an indirect pathway (gasification) as in Fischer-Tropsch processes. IER claims that its process generates 60% less CO2 than the most widely available coal-to-liquids technology and can generate clean fuels from biomass that are carbon negative.

Supercritical water is water above its critical point—the temperature and pressure under which phase boundaries (between solids, liquids and gases) cease to exist. Supercritical water dissociates into OH- (base) and H+ (acid) molecules, creating a substance that is simultaneously a strong acid and a strong base. Although normally acids and bases neutralize each other, they can’t at supercritical temperatures and pressures, IER says. The strong acids and bases attack weak links in organic polymers, which are broken directly into valuable oils and solid products. _GCC

Other viable approaches for cleanly extracting energy from low quality coals involve gasification of coal and catalytic synthesis of fuels.

Gasification can be applied to almost all forms of carbon, including black liquor from paper / pulp works.

The ability to take a dirty and worthless waste product and turn it into something quite clean and valuable is the mark of a civilisation that is beginning to find its way -- at least in this narrow area of cleaning up after itself.