wec v exergen techs...

Further to CM's Q:

WEC uses coal fired power to create a hot gas to evaporate water out of the coal. Exergen uses a process known as Continuous Hydrothermal Dewatering (CHTD) which removes the water in the liquid state as it would have occurred in nature with heat and pressure.

The Exergen process uses head pressure (i.e. free energy from gravity) so that only 2% of the energy within the coal is used for the upgrading process, whereas WEC uses coal fired power and is in the region of 20% of the coal energy is used.

Another advantage of the Exergen process is, as the process requires the coal to be mixed into slurry to start with, a proportion of ash can be removed.

Also a proportion of sulphur and salts are also removed in the CHTD process, increasing the value of the end product.

Additionally, for those concerned re suplhur levels, new scrubber technologies and addition of calcium in the burners can reduce sulphur levels reaching the atmosphere significantly.

The Exergen process uses the least amount of energy in the coal to convert the brown coal to black coal equiv (BCE). Hence, Exergen's CHTD produces an end product with the greatest calorific value (CV), which is what buyers of the BCE primarily want.

Additionally, the energy required to make the BCE is minimal in Exergen's tech (heat and pressure), whilst other tech's require coal fired power (more energy). (An arguement in favour of ESI Coldry tech is that it is waste heat, however it still needs coal fired power to work). So energy wise, Exergen BCE cheaper to produce.

Also, another advantage further to point above, is that Exergen CHTD autoclave can be built anywhere - BM, LV, etc., ideally right next to the mine. Other tech's that require coal fired power need to be positioned near coal fired generators ie. LV.

So, least amount of external energy to create the BCE and a high CV BCE as well makes Exergen's tech the leader of the pack (in these author's humble opinions ;o).

Cheers K and V