Semi-coke (also called char) is the solid carbon-rich residue left after the volatile fraction of coal or oil shale has been driven off by Destructive Distillation. It is the solid co-product of Low-Temperature Carbonization (LTC) and, by extension, of the karrick-process as described in the source dossier.
Distinction from coke
Conventional high-temperature coking produces a harder, more fully devolatilized coke. The supplied source describes low-temperature carbonization at steam temperatures of roughly 1000–1400 °F and notes the residue retains more volatile matter than high-temperature coke, making it softer — hence "semi-coke."
Role in the source
The dossier lists the principal products of low-temperature carbonization as smokeless fuel, tar-oils and gas; the solid residue is the smokeless fuel. No compositional or calorific data for the semi-coke is supplied in the ingested material.
Related
- Low-Temperature Carbonization (LTC)
- karrick-process
- Coal Tar
Source notes & attribution
- https://rexresearch.com/karrick/1larstz.htm