Year: 1895

page_text: Date of Application, 2nd Aug., 1895
Complete Specification Left, 2nd June, 1896-Accepted, 4th July, 1896
I, JOHN BOWING of Tilbury in the County of Essex, Consulting Chemist, do
hereby declare the nature of this invention to be as follows:-
In the Specifications left by me at the Great Seal Patent Office in pursuance of
applications for certain Letters Patent viz. 10137 of 1888, 9199 of 1890, and 1682
of 1891, I have described methods by which coal may be prepared for coking and
then coked.
Now I have discovered that many coals may be coked according to the methods
hereinafter described and although I have described these methods in reference to
three classes of coal viz. steam coal which is a coal which cokes with difficulty,
bituminous coals which coke with ease, and coals of an intermediate character, it
must be understood that there is no clear dividing line by which coals can be
separated into classes according to their facility for coking. All coals differ in
this respect, and trial alone can determine whether any particular sort of coal
cokes easily or not.
But taking the coal commonly known in South Wales as steam coal as an
example of one which cokes with difficulty I find that it may be made into dense
clean hard coke in the following manner.
The coal is in the first place reduced to a comparatively fine state of subdivision
for example until it is small enough to pass through a quarter inch mesh or taken
in the form of slack. It is thoroughly wetted and a small proportion of tar added
and the whole thoroughly mixed so that the tar shall as nearly as possible be
evenly distributed throughout the mass: I have found by trial that as small a
proportion of tar as 24 per cent. by weight of the weight of the coal is amply
sufficient. After the mixing has been effected the wet mixture is put into a closed
vessel and tamped or squeezed down so as to make it as solid as possible: This
part of the operation must be conducted with care for if the coal is in a loose
conditiou, the small pieces of coal will coke into correspondingly small pieces of
friable coke, instead of uniting into large dense masses. The vessel may now be
raised to the coking temperature in any convenient furnace, and the more rapidly
the better and the products of distillation are allowed to escape through any
suitable orifice in the vessel. In a few hours the coking will be completed.
In dealing with a sort of coal which cokes very readily in masses but which when
in the condition known as slack, yields poor results when treated in the ordinary
methods, I have discovered that such slack may be readily coked without tar or
water if it is placed in a suitable vessel and precautions be taken equivalent to the
squeezing or tamping mentioned above, to keep the particles of coal in close contact
during the coking operation.
This may be effected either by almost completely filling the vessel so as to give
very little room for movement, or by placing a heavy weight on the surface of
the coal, but it is not sufficient with coals of this class to merely tamp or squeeze,
in consequence of the tendency to swell which such coals exhibit when heated.
1
In dealing with the slack of coals of an intermediate class which do not swell
much on heating the tar may be dispensed with and in some cases the water also
and they may be coked either by filling the vessel with coal or by putting a
weight on them, or, if they approximate to the steam coal class by squeezing or
tamping them.

page_text: I have found when coking steam coal in the manner above mentioned that a
very convenient form of vessel is an iron cylinder about three feet in diameter
placed on end which can be made of any length adapted to the furnace in which
the heat is generated.
It may be desirable in some cases to inject volatile hydrocarbons into the mass
during the coking operation which are broken up at the coking temperature and
assist in cementing the mass together.
Dated this Second day of A nonot 100%
:
1 JOHN BOWING of Tilbury in the County of Essex Consulting Chemist, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement :-
In the Specifications left by me at the Great Seal Patent Office in pursuance of
applications for certain Letters Patent viz. 10137 of 1888, 9199 of 1890 and 1682
of 1891 I have described methods by which coal may be prepared for coking and
then coked.
Now I have discovered that many coals may be coked according to the methods
hereinafter described and although I have described these methods in reference to
three classes of coal viz. steam coal which is a coal which cokes with difficulty
bituminous coals which coke with ease and coals of an intermediate character it
must be understood that there is no clear dividing line by which coals can be
separated into classes according to their facility for coking. All coals differ in
this respect and trial alone can determine whether any particular sort of coal
cokes easily or not.
But taking the coal commonly known in South Wales as steam coal as an
example of one which cokes with difficulty I find that it may be made into dense
clean hard coke in the following manner. The coal is in the first place reduced to
a comparatively fine state of subdivision for example until it is small enough to
pass through a quarter inch mesh or taken in the form of slack. It is thoroughly
wetted and a small proportion of tar added and the whole thoroughly mixed so
that the tar shall as nearly as possible be evenly distributed throughout the mass.
"I have found by trial that as small a proportion of tar as 24 per cent. by weight of
the weight of the coal is amply sufficient. After the mixing has been effected the
wet mixture is put into a gastight vessel filled full and made as solid as possible
by tamping or squeezing. This part of the operation must be conducted with care
for if the coal is in a loose condition the small pieces of coal will coke into corre-
pondingly small pieces of friable coke instead of uniting into large dense masses.
The vessel may now be raised to the coking temperature in any convenient
'furnace and the more rapidly the better and the products of distillation are
allowed to escape through any suitable orifice in the vessel. In a few hours the
coking will be completed.
In dealing with a sort of coal which cokes very readily in masses but which
when in the condition known as slack yields poor results when treated in the
ordinary methods, I have discovered that such slack may be readily coked
without tar or water if it is placed in a suitable vessel and precautions be taken
equivalent to the squeezing or tamping mentioned above to keep the particles of
coal in close contact during the coking operation. This may be effected either by
completely filling the vessel so as to give no room for movement, or by placing a
heavy weight on the surface of the coal, but it is not sufficient with coals of this

page_text: class to merely tamp or squeeze in consequence of the tendency to swell which
such coals exhibit when heated.
In dealing with the slack of coals of an intermediate class (which do not swell
much on heating) the tar may be dispensed with, and in so ne cases the water also-
and they may be coked by filling the vessel with coal or by putting a weight on
them and if they approximate to the steam coal class by squeezing or tamping them
as herein before described.
I have found when coking steam coal in the manner above mentioned that a
very convenient form of vessel is an iron cylinder about 3 feet in diameter
which can be made of any length adapted to the furnace in which the heat is
generated.
It is desirable especially in the case of coals which coke with difficulty to allow
volatile products such as are given off during the coking operation to pass into the
mass which is being or to be coked either during or prior to the commencement of
the coking operation.
These products if passed in during the coking operation are broken up and
assist in cementing the mass together or if passed in prior to the coking operation
make the consequent coking operation more effective.
I have found that the most economical method of doing this is to cause these
products which are driven off from one charge, during the coking operation to pass
into and condense in the next charge, which for this purpose is placed in any
convenient position near to the charge which is actually being coked.
When this next charge is in its turn transferred to the coking retort these.
products which it will give off in its turn are passed as before into the next
succeeding charge, and so on.
I do not however restrict myself to the use of products so evolved, inasmuch as
they may be specially prepared for this purpose, nor do I limit myself to the use
of such products as aforesaid prior to the commencement of the coking operation
in the charge into which these products are passed, as they may be passed in
during that operation.
Having now particularly ascertained and described the nature of my invention
and the manner in which it is to be performed, I claim.
(1) Coking slack or small coal in a closed retort in the manner described with.
reference to steam coal.
(2) Coking slack or small coal in a closed retort in the manner described with.
reference to the more easily coking varieties of coal.
(3) In coking slack or small coal in closed retorts keeping the particles of coal
during the coking operation in close contact with one another either by squeezing,.
tamping, weighting or confining the coal substantially as described.
(4) Conducting volatile products into a charge which is to be subsequently coked
substantially as described.
(5) The methods of coking claimed in the first three claims in combination with.
he use of volatile products as herein before described.
Dated the 2nd day of June 1896.
JOHN BOWING.