IMPROVEMENTS IN THE UTILIZATION OF COAL TAR AND THE PRODUCTS ARISING FROM THE DISTIL- LATION THEREOF. AND IN THE APPARATUS EMPLOYED THRDRIN
Year: 1868

page_text: LETTERS PATENT to Edward Dorsett, of 12, London Street, in the
City of London, for the Invention of "IMPROVEMENTS IN THE
UTILIZATION OF COAL TAR AND THE PRODUCTS ARISING FROM THE DISTIL-
LATION THEREOF. AND IN THE APPARATUS EMPLOYED THRDRIN "
Sealed the 17th July 1868, and dated the 18th January 1868.
PROVISIONAL SPECIFICATION left by the said Edward Dorsett at
the Office of the Commissioners of Patents, with his Petition, on
the 18th January 1868.
I, EDWARD DORSETT, of 12, London Street, in the City of London,
do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN THE UTILIZATION OF COAL TAR AND THE PRODUCTS ARISING FROM
THE DISTILLATION THEREOF, AND IN THE APPARATUS EMPLOYED THEREIN," to be
as follows:-
My Invention has for its object the utilization of creosote for
effecting the distillation of coal tar and other purposes for which heat
is required.
A boiler a (see the accompanying two Sheets of Drawings) is provided
for containing the said creosote, and a fire-grate is arranged at the base

page_text: of the said boiler, from which a flue a¹ passes through the creosote
contained therein to a chimney a³. At a convenient distance above
the said grate a perforated tube 6 is placed, which communicates by
means of the tube 6' with the vapour space above the level of the
creosote. Partially around the base of the said boiler a is a tank c which
serves as a reservoir for containing the creosote before its delivery into
the said boiler, and by reason of its close proximity thereto the creosote
therein contained is heated to a certain extent before its admission into
the boiler a. This said boiler a is provided with an ordinary water
guage d, which serves to indicate the height of the creosote, also with a
pressure guage e for indicating the pressure of the vapour in the boiler,
and a safety valve f is fixed to the top thereof. A boiler 9 is also
provided of any suitable size and shape, that indicated by the Drawings
preferred, in which said boiler the tar or other fluid to which heat is
to be applied is placed. The boiler shewn in the Drawing is concave
at g and is set in brickwork and provided with a grate g³ at its
base. At a convenient distance above the said grate is a per-
forated tube h communicating with the boiler a by means of the
pipes, and after passing around the inside of the concave part of the
boiler terminating in a cock ¹ outside the brickwork setting. At
the summit of the said boiler g is a pipe i leading to a condenser in the
ordinary manner. At a convenient distance from the boiler a is a small
condenser j, into which a pipe k leading from the vapour space of the
boiler a is brought. At the point where the said pipe enters the said
condenser it is made in the form of a worm and terminates in a
cock m on the outside of the said condenser. The boiler a is mounted
on a trolly c³, so that it may be moved from one boiler to another as
required, or if preferred the boiler a may be fixed at any convenient
distance from the said boiler g.
The action of the apparatus is 'as follows:Creosote is pumped into
the boiler a through the opening n by means of the force pumps c²,
or an injector may be used if desired. A small quantity of lighted
coal or other fuel is placed on the grate in the boiler a, and the fire
is kept up therein till the vapour given off from the creosote has
arrived at a sufficiently high pressure for the purpose required. The
cock b on the pipe 6' is then opened and the vapour issues from the
perforations in the tube band is ignited by the fire beneath; the
pressure can then be maintained in the boiler a by means of the ignited

page_text: vapour without the addition of any more fuel. The cock on the
pipe is also opened, and the vapour rushes through the perforations
in the pipe and is ignited by the fire on the grate g³, or in any other
convenient manner, as before described, and impinges on the plates of
the boiler g at g' in such manner as to cause the distillation of the tar,
the evaporation or distillation of any other liquid, or the generation
of steam in marine or other boilers. In the event of there being
too high a pressure in the boiler a the cock k¹ on the pipe k is opened,
and a portion of the vapour from the boiler a is condensed in the
condenser and issues in the form of oil from the cock m, and may
be again used, as before described.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Edward Dorsett in the Great Seal Patent Office
on the 18th July 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
DORSETT, of 12, London Street, in the City of London, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of January, in the year
of our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Edward Dorsett, Her special licence that I,
the said Edward Dorsett, my executors, administrators, and assigns, or
such others as I, the said Edward Dorsett, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to
time and at all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN THE UTILIZATION OF
COAL TAR AND THE PRODUCTS ARISING FROM THE DISTILLATION THEREOF, AND IN
THE APPARATUS EMPLOYED THEREIN," upon the condition (amongst others)
that I, the said Edward Dorsett, my executors or administrators, by
an instrument in writing under my, or their, or one of their hands
and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six

page_text: calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Edward Dorsett, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the accompanying
Sheet of Drawings (that is to say): :-
My Invention has for its object improvements in the production
and utilization of the heavy mineral oils which are produced by the
distillation of coal tar, cannel, boghead, and other coal and coal shales,
and which are known in commerce as coal oil, dead oil, shale oil,
creosote, napthaline, &c. I employ these liquid hydrocarbon matters
in the manner herein-after described; in the first place for their own
distillation or production; and, secondly, for the production of heat
generally, and more particularly to the heating of steam boiler and
other furnaces.
And in order that my said Invention may be more fully understood
I now proceed to establish what I consider the distinctive modifications
of this my Invention, which are,―
First. The employment of a separate generator or boiler for the
production of vapour from the mineral oils, which said vapour is
therein maintained under pressure, which may vary according to the
quantity of mineral oil required to be vaporized by the apparatus at
from 10 lbs. to 60 lbs. or more upon the square inch, under which
pressure the vaporized mineral oil is supplied by pipes in the same
manner as steam to a small pipe or series of pipes, each pipe being
perforated with from 4 to 6 small holes, and which pipes are placed
inside each separate furnace of a steam ship, or under each boiler for
generating steam or distilling coal tar and other matters.
Second. The continuous action of the apparatus after pressure has been
formed therein. The small boiler or generator burns its own vapour to
produce and maintain a constant supply, not only sufficient to heat
itself, but to heat any number of furnaces according to its size and
evaporating power. The quantity of vapour formed in the generator
and distributed to the furnaces to be heated by it may be varied at
will by the pressure that is maintained in the said generator and the
quantity of mineral oil which is passed through it by means of the
force pump or injector employed to feed it..

page_text: Third. The creating, maintaining, or augmenting the said pressure
by means of water admitted into the boiler in very small quantities,
or in other cases by a small quantity of steam, which is allowed to
enter the conduit pipes and mix with and to be superheated by the heat
of the vapour in its passage through the pipes between the generator
and the furnaces where it is burned.
I shall now proceed to described the explanatory Sheet of Drawings
which I have hereunto appended for the purpose of shewing a simple
method of applying my Invention to the heating of tar, schiste oil, and
petroleum or other stills.
a represents a boiler or generator for containing the said mineral oil,
and a fire-grate is arranged at the base of the said generator from which
a flue a passes through the mineral oil or creosote contained therein to
the chimney a³. At a convenient distance above the said grate a
perforated tube 6 descends from the crown of the boiler or generator
by means of the tube 6. This tube is commanded by a stop valve or
cock, and is used to maintain the heat in the boiler or generator by the
combustion of the vapour escaping through it from the vapour space in
the boiler itself to the grate below. Partially around the base of the
said boiler or generator a or in other cases entirely disconnected from
it is a tank c, which serves as a reservoir for containing the mineral
oil or creosote before its delivery into the said boiler by the force
pump c. The said boiler or generator a is also provided with guage
cocks, safety valves, and pressure guages similar to an ordinary steam
boiler; a heat guage is also applied through a tube descending into the
interior. Suitable stop valves connected with the pipe h³ form the
communication or passage for the vapour produced in the boiler or
generator a to the burner or tube perforated with holes h. These
perforations are of 1 of an inch diameter, or thereabouts, and 4 or 5
of them are sufficient to supply the vapour to work an ordinary tar
boiler holding 4,000 gallons, or to heat an ordinary steam boiler of 40
to 50 horse power.
In some cases, as in tar or shale works, the
generator a is placed on wheels attached to itself, and is employed to
heat several furnaces in succession in different parts of the same
establishment; or it may be employed to heat several stills or boilers
placed together at the same time.
The action of the apparatus is as follows:-The creosote or mineral
oil is pumped into the boiler or generator a through the opening n by

page_text: means of the force pump c², or an injector may be used if desired. A
small quantity of lighted fuel is placed on the grate in the generator a,
and the fire is kept up therein till the vapour given off from the mineral
oil has arrived at a sufficiently high pressure for the purpose required.
The cock or valve 62 on the tube 6 is then opened, and the vapour
issues from the perforations in the tube b¹ and is ignited by the fire
beneath. The pressure can then be maintained in the boiler a by means
of the ignited vapour alone without the addition of any more fuel. The
valve h on the pipe 8 is also opened, and the vapour rushes through
the perforations in the tube h, where it is also ignited upon or under
the grate of the furnace it is intended to heat, as shewn in the Drawing
of the boiler g. In the event of there being too high a pressure a
condenser may be used, as shewn, but under ordinary circumstances I
'find it only necessary to check the issue of the vapour from the boiler à
to the tube 6 that serves to heat the said boiler or generator. Such is
à description of my said Invention as applied to the heating of tar and
petroleum boilers or stills; it is obvious that the same may be applied
to many other purposes, to heating furnaces for melting glass and
metals, and particularly to the heating of marine and other steam
boilers or furnaces. For this purpose I employ the generator or
boiler a, as before described, or some modification thereof, in which the
creosote or mineral oil is heated in volume for the purpose of dis-
tributing it in the vaporised state under pressure by means of the
pipe h³, which in this case may have several branches or outlets passing
into or under the several boiler furnaces of a steam ship. In some
cases I assist the production of a pressure in the boiler a by a small
quantity of water introduced with the mineral oil through the force
pump, which for this purpose is provided with a double suction pipe
and stop-cocks to regulate the quantity introduced. In other cases I
admit steam into the pipe h³ between the boiler a and the burner h in
the furnace; the steam mixes with the mineral oil vapour, which has
a temperature of from 400° to 600°, and passes through the pipe h³ with
the vapour, increasing its volatility and aiding its combustion when it
escapes with it through the perforated holes in the pipe h.
Having now described the nature of my said Invention, and the
manner in which the same is to be practically carried into effect, I
claim as the Invention secured to me by the herein-before in part
recited Letters Patent,- :

page_text: First. The general arrangement of apparatus and the method employed
to vaporise coal tar, shale, and other mineral oils as herein-before
described, or any mere modification thereof.
Second. The general arrangement and construction of apparatus for
the utilization of the said mineral oil vapour for the purpose of
generating steam and the production of heat generally as herein-before
described, or any mere modification thereof.
EDWARD DORSETT. (L.s.)