IMPROVEMENTS IN THE PROCESS OF AND APPARATUS FOR DISTILLING COAL, AND OTHER CARBONACEOUS MATERIALS, IN ORDER TO OBTAIN COKE, TAR, OILS, AMMONIA COMPOUNDS, HEATING GAS AND OTHER VALUABLE PRODUCTS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by John Woodhead at the Office of the
Commissioners of Patents on the 6th March 1883.
JOHN WOODHEAD of Manor Collieries, Wakefield in the County of York,
Colliery Proprietor. "IMPROVEMENTS IN THE PROCESS OF AND APPARATUS FOR
DISTILLING COAL, AND OTHER CARBONACEOUS MATERIALS, IN ORDER TO OBTAIN
COKE, TAR, OILS, AMMONIA COMPOUNDS, HEATING GAS AND OTHER VALUABLE
PRODUCTS
"
This Invention consists in the first place of an Apparatus consisting of an oven
or Producer in the shape of a vertical cylinder of wrought iron lined at the bottom
and sides with fire brick ganister or other refractory material. The top is covered
in with a dome of Fire brick or other refractory material supported by the side
lining a hole is left in the top of the dome for the admission of the charge of coal,
the said hole is secured when the oven is in action by an airtight lid. Just below
the springing of the dome is an outlet for the Gases driven off in the working.
The bottom of the oven is of wrought iron and in the centre is an aperture for the
admission of air which is blown in through a detachable nozzle either by means
of a jet of steam or a fan; a round chamber is formed of firebrick or other refractory
material immediately over the air inlet and standing a few inches above the
bottom lining of the oven, this is covered by a thick round slab of firebrick made
for the purpose and ports are left in the wall of this chamber through which the
air escapes into and promotes the combustion of the coal in the oven At opposite
sides and close to the bottom of the oven are two closely fitting doors for the
removal of the Coke or clinkers as the case may be. There are also two connections
bolted onto the sides or bottom of the oven at opposite points. Should it be more
convenient the arrangement for admitting the charge of Coal may consist of a
hopper and suspended cone
The mode of working is as follows. If it be desired to manufacture Coke and
to collect the Tar oils, Ammonia Compounds and the like, the oven is charged and
the charge ignited a blast of air is then applied at the bottom of the Apparatus
and when smoke begins to issue from the charging hole at the top, the lid is put
on and the gases drawn from the oven through suitable pipes by means of an
[Price 2.11

page_text: exhauster which may be of any of the well known forms but preferably that known
as the Steam Jet Exhauster and forced through Condensers of any convenient
kind―Here the Tar, Oils and a portion of the Ammonia Compounds are extracted,
the Gas then passes through scrubbers or washers (also of any convenient kind) and
here the rest of the ammonia compounds and any other matters not retained by
the condensers are separated. All these valuable matters will be stored in suitable
receptacles for sale or further treatment
After leaving the scrubbers or washers the gases are led through pipes back
ngain to the oven and passing through the connections before mentioned are
absorbed by the incandescent material therein the blast is now either shut off
completely or greatly reduced and only sufficient air admitted to allow the coking
process to be completed. When the coke is removed and on a fresh charge being
added the process is repeated. If there be more than one oven it would be found
expedient to lead the gases back to those nearly burnt off and shutting off the air
entirely allow them to become absorbed by the Coke. The oven is provided with
sight holes similar to those attached to foundry cupolas to enable the man in charge
to see and adjust the air supply according to requirements
Should it be desired not to make Coke but to make heating gases and still
separate the valuable Tar, Oils Ammonia Compounds and the like the process is
carried on in precisely the same manner as that herein before described with the
exception that the Gases are not led back to the oven but after being deprived of
their valuable superfluities in the manner herein before described are conducted
to a gas flue and after all the rich gases have been gently expelled from the charge
a powerful blast of air is supplied at the bottom of the oven and the coke is
converted into ordinary Generator gases consisting chiefly of Carbonic Oxide. To
improve the quality and strength of these gases and also because there would be a
considerable quantity of Nitrogen left in the Coke and also carried in with the
blast which the presence of steam would convert into Ammonia it is advisable to
create this strong blast by means of a jet of steam which is preferably superheated,-
the steam passing through the glowing fuel will be split up into Oxygen and
Hydrogen the Oxygen will combine with the carbon and form Carbonic Oxide
while part of the Hydrogen will combine with the Nitrogen and form Ammonia
and the rest will pass unaltered and form with the Carbonic Oxide a heating gas
of great power and utility. These gases can be passed through scrubbers or
washers to extract the ammonia and then be passed into the gas flue and mixed
with the rich gases given off in the first stage, or if so desired they can be passed
hot into the gas flue direct from the oven. In order to obtain a Gas of uniform
quality it will be necessary to have a series of ovens so arranged that the two
stages are always proceeding at one and the same time
The gases so obtained are admirably suited for burning bricks-for Chemical
Works or for almost any other industrial application where heating gases are
required
1
.
If it be inconvenient to have more than one oven the gases as they are given
off can be stored in a gas holder and there intermixed with each other