'Coke' may be described as the cellular residue from the
carbonisation of a coking coal in commercial ovens or-retorts
at a temperature of about 9000C; and a 'Coking coal' as a
coal which will yield a commercial coke when it is carbonised.
Some of the questions arising from these descriptions are:-
What are the standards required of a commercial coke; what is
the cause of coke-formation; what are the characteristics of
coking coals and how may they-be judged; and how can the
quality of coke be improved?
It is not proposed to discuss these questions in detail
but it is important to be aware of them in order to understand
the way the coking industry has developed. These questions
have been asked since coke has been used on a commercial scale
and the answers to them have altered with circumstances as
science and technology have changed.
The qualities which render a coke most useful, or most
readily saleable vary according to the use to which it is to
be put. For all combustion processes, which account for most
of the coke used, it would be expected that the intrinsic 'combustibility' would be important. The manner in which a
ooke burns depends-so much however upon such factors asp for example, the size of the pieces and the rate of supply of air
to the fuel-bed, that differences in intrinsic combustibility
may be masked. From observation of the various factors upon
whioh the usefulness of a coke for particular purposes depends,
it is possible to indicate
those qualities of a coke which
render it most valuable, for all, or most, purposes (Continues...).
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.