Presupposing an economic coal liquefaction and gasification technology in the future, these alternative carrying media would have the great advantage over water that they can be produced in part from the coal itself, do not freeze at subzero temperatures – i.e. the pipelines need not be buried – and represent in themselves substances of value for transportation and not ballast.
In addition, the use of ethanol and LNG slurries is discussed.
This should not be confused with methods whereby up to 10% oil is added to ultra fine grained argillaceous coking coals before hydraulic handling whereby an agglomeration effect is obtained for the coal, a separating effect for the clay components upon leaving the pipeline and an improvement in the coking properties of the coal.