Semi-coke is used as a domestic fuel or by the transformation plant itself.

Semi-coke (a solid product obtained from carbonization of coal at low temperature) should be included in this category.

The residue (char or semi-coke) remains in the retort.

While the produced liquids are mostly a by-product, the semi-coke is the main product, a solid and smokeless fuel.

Spent shale (semi-coke) is transported then to the separate furnace for combustion to produce hot ash.

This heading also includes coke, coke breeze and semi-coke made from lignite/brown coal.

Most of solid heat carrier processes creates coke-ash residue as the semi-coke created during the process is combusted for the process energy needs.

Coke and semi-coke of coal, of lignite or of peat, whether or not agglomerated; retort carbon.

Necessary heat for pyrolysis is generated in the carbon recovery section by combustion of carbon residue (char or semi-coke) remained in the spent oil shale.

Nine million tonnes of mining waste, eight million tonnes of oil shale ash, and one million tonnes of semi-coke were generated.

By time-being, the combustion zones moved downward, and the char (semi-coke) produced as a solid residue of pyrolysis, ignited to burn as additional fuel for combustion.

Semi-coke can be used for utility boilers and coking coal in steel smelters, yields more heat than raw coal and can be converted to water gas.

A decomposition is caused by mixing raw oil shale with a hot oil shale ash, generated by combustion of carbonaceous residue (semi-coke) in the spent residue.

According to this, production of a barrel of shale oil can generate up to 1.5 tonnes of semi-coke, which may occupy up to 25% greater volume than the original shale.

As semi-coke consists of, in addition to minerals, up to 10% organics that may pose hazard to the environment owing to leaching of toxic compounds as well as to the possibility of self-ignition.

ENRC's chief executive, Johannes Sittard, said the acquisition secures 'a reliable and cost effective supply of relatively high quality thermal coal and semi-coke, thereby further enhancing the group's position as a low cost producer.'

In the direct retort, oil shale moves past ducts through which are provided hot inert gas for heating the raw oil shale, air for combustion of carbon residue (char or semi-coke) in the spent oil shale, and cold inert gas for cooling the spent oil shale.