IMPROVEMENTS IN THE MANUFACTURE OF GAS, ALSO IN THE MANUFACTURE OF COKE AND OTHER FUEL
Year: 1858

page_text: LETTERS PATENT to George Hinton Bovill, of Durnsford Lodge, Wimbledon,
in the County of Surry, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF GAS, ALSO IN THE MANUFACTURE OF COKE AND OTHER FUEL."
Sealed the 4th February 1859, and dated the 6th August 1858.
PROVISIONAL SPECIFICATION left by the said George Hinton Bovill at
the Office of the Commissioners of Patents, with his Petition, on the
6th August 1858.
I, GEORGE HINTON BOVILL, of Durnsford Lodge, Wimbledon, in the County
of Surry, do hereby declare the nature of the Invention for "IMPROVEMENTS
IN THE MANUFACTURE OF GAS, ALSO IN THE MANUFACTURE OF COKE AND OTHER
FUEL," to be as follows:-
This Invention has for its object improvements in the manufacture of gas,
also in the manufacture of coke and other fuel.
In the manufacture of gas, according to my Invention, I combine with
retorts from which gas is collected, other retorts or ovens by which only coke
is produced; the gases produced in these latter retorts being consumed, and
serving by their combustion to maintain the necessary temperature both in the
gas retorts and in the coke ovens, or those retorts by which coke only is
produced. The retorts are arranged in a vertical position, or so slightly
inclined that the materials which they contain will descend in them by their
own weight; they are so arranged that adjoining each retort from which gas
is collected there is another which produces only coke, and this is separated
from the gas retorts by a thin wall of fire brick (that being the material of
which the retorts are constructed. Surrounding each set of ovens or retorts

page_text: are flues, with which the coke oven communicates; in these flues the gases
passing from the coke oven are consumed, and assist in heating the coke ovens
and gas retorts. Within each of the gas retorts there is a tube passing from
end to end of the retort, and perforated to facilitate the escape of the gas-; this
tube is formed in sections, each of which is (say) one-third of the length of
the retort, and has a flange at its end so nearly fitting the retort as to prevent
the material which the retort contains from passing it. These flanged pipes
are employed to facilitate the charging and discharging of the retort when a
part only of the charge is drawn at one time, and which is done in the follow-
ing manner The cover at the upper end of the retort is removed, and a
bar is introduced into the interior of the tube within it, so as to get a firm hold
of the two uppermost sections; the bottom is then removed from the retort,
when the lowest section of the tube, with the coke which it sustains, falls out;
the bottom is then replaced, and the other sections of tube allowed to descend
on to it, thus leaving the upper third of the retort vacant to receive the charge.
The coke ovens are charged from time to time in a similar manner, that is
to say, a charge equal only to a part of the contents of the retort is introduced
at one time, by which excessive cooling of the retorts and ovens is avoided.
In the coke ovens it is not necessary to use tubes, as when discharging the coke
that which is above the portion to be discharged is supported for the time
by bars introduced for the purpose; the gas may be collected either from the
top or the bottom of the retorts; if it be taken from the top, a rich gas will be
obtained, but the coke will be porous, like ordinary gas coke; if the gas be
taken from the bottom, an increased quantity of poorer gas will be obtained,
and at the same time a denser coke will be produced. These changes are
consequent upon the tarry vapors being caused to pass over the already
incandescent coke. Retorts for the manufacture of gas may be set horizontally
in combination with the coke ovens, so arranged to be charged at the top and
discharged at the bottom, as before described; and I prefer to arrange the said
gas retorts so that their sides shall form a portion of the wall of the coke oven,
and the coal distilled and carbonized by the heat of the coke ovens and gases
therefrom; retorts so set would be charged and drawn in the usual way, the
heat being kept up by the-method before mentioned of working the coke ovens.
When it is desired to manufacture coke without at the same time producing-
and collecting gas, I employ ovens of a similar description to those before
described to be used in conjunction with gas retorts, viz., arranged so as to be
charged at the top and discharged at the bottom, and separated the one from
the other by thin division walls, through which the heat is communicated with
considerable facility. In working these ovens, I so arrange that when one of

page_text: the ovens is charged with fresh coal or fuel, the two adjacent ovens shall be in
full operation, that is to say, with the material which they contain at a red
heat throughout.
In the manufacture of gas and coke I find it sometimes advantageous to
employ a mixture of peat and tar or pitch; the resulting coke is of great
purity and otherwise of good quality. Peat may be mixed with tar for fuel,
by taking the pieces of peat in the form in which they are cut, but first dried,
and immersing them in the tar. Peat prepared in this manner, and afterwards
baked without raising it to a red heat, is suitable for use as fuel for many
purposes for which unprepared peat cannot conveniently be employed. When
the peat is too dense for the tar thoroughly to penetrate it by simple immersion,
I force the tar, or a mixture of pitch and tar, or tar from which a portion of
the naptha or oil has been distilled, thoroughly into the peat, by placing the
peat in a closed vessel, and pumping the bituminous matter into it under
sufficient pressure to accomplish the object; pitch may be injected into the
peat in this way by heating the vessel so as to keep the pitch in a fluid state.
After the vessel has been filled and the pitch is in a fluid state, I prefer to
obtain the pressure necessary for injecting the pores of the peat by pumping
in tar, as that will not clog or interfere with the working of the pumps.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Hinton Bovil in the Great Seal Patent Office on
the 5th February 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
HINTON BOVILL, of Durnisford Lodge, Wimbledon, in the County of Surrey,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of August, in the year of our Lord One
thousand eight hundred and fifty-eight, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said George Hinton Bovill, Her special licence that I, the said George
Hinton Bovill, my executors, administrators, and assigns, or such others
as I, the said George Hinton Bovill, 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

page_text: Invention for "IMPROVEMENTS IN THE MANUFACTURE OF GAS, ALSO IN THE MANU-
FACTURE OF COKE AND OTHER FUEL," upon the condition (amongst others) that I,
the said George Hinton Bovill, my executors or administrators, by an instru-
ment 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 calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said George Hinton Bovill, do hereby
declare the nature of the 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, that is to say:-
This Invention has for its object improvements in the manufacture of gas,
also in the manufacture of coke and other fuel.
In the manufacture of gas, according to my Invention, I combine with
retorts from which gas is collected, other retorts or ovens by which only coke
is produced, the gases produced in these latter retorts being consumed and
serving by their combustion to maintain the necessary temperature, both in
the gas retorts and in the coke ovens, or those retorts by which coke only is
produced. The retorts are arranged in a vertical position, or so slightly
inclined that the materials which they contain will descend in them by their
own weight; they are so arranged that adjoining each retort from which gas
is collected there is another which produces only coke, and this is separated
from the gas retorts by a thin wall of fire brick (that being the material of
which the retorts are constructed). Surrounding each set of ovens or retorts
are flues with which the coke oven communicates; in these flues the gases
passing from the coke oven are consumed, and assist in heating the coke ovens
and-gas retorts. Within each of the gas retorts there is a tube passing from
end to end of the retort, and perforated to facilitate the escape of the gas;
this tube is formed in sections, each of which is (say) one-third of the length
of the retort, and has a flange at its end so nearly fitting the retort as to
-prevent the material which the retort contains from passing it; these flanged
pipes are employed to facilitate-the-charging and discharging of the retort
when a part only of the charge is drawn at one time, and which is done in-the-
following manner :-The cover at the upper end of the retort is removed, and
a bar is introduced into the interior of the tube within it, so as to get a firm
hold of the two uppermost sections; the bottom is then removed from the
retort, when the lowest section of the tube with the coke which it sustains falls
out the bottom is then replaced, and the other sections of tube allowed to

page_text: descend on to it, thus leaving the upper third of the retort vacant to receive
the charge. The coke ovens are charged from time to time in a similar
manner, that. is to say, a charge equal only to a part of the contents of the
retort is introduced at one time, by which excessive cooling of the retorts and
ovens is avoided. In the coke ovens it is not necessary to use tubes, as when
discharging the coke, that which is above the portion to be discharged is
supported for the time by bars introduced for the purpose. The gas may be
collected either from the top or the bottom of the retorts; if it be taken from
the top, a rich gas will be obtained, but the coke will be porous, like ordinary
gas coke; if the gas be taken from the bottom, an increased quantity of poorer
gas will be obtained, and at the same time a denser coke will be produced.
These changes are consequent upon the tarry vapours being caused to pass
over the already incandescent coke.
The Drawings hereunto annexed show different views of gas retorts combined
with coke ovens in such manner that the former may be heated by the latter,
as above described.
a, a, are the gas retorts, and b, b, the coke ovens placed between them;
.c, c, are flues passing from the coke ovens, and enveloping the gas retorts on
three sides, the fourth side of each of the gas retorts forming a side of one of
the coke ovens ; & is the chimney; e, e, are slides, by which the flues next
either of the gas retorts may be closed; f, f, are gratings at the top of the
coke ovens, by which they are charged, and by which air is allowed to pass
into them to maintain the necessary amount of combustion, and the intensity
of the combustion may be regulated by more or less covering these gratings,
as may be required.
The red lines at h show the position of the rods which are introduced while
drawing the coke from the lower portions of the coke ovens to sustain the
coke above till the drawing operation is finished, when it is allowed to descend,
and the space is filled by fresh fuel introduced at the top. The gas retorts a
are, as will be seen, fitted both at top and bottom with covers secured by
screws, and which are removed for charging. i, i, are pipes proceeding both
from the top and bottom of the gas retorts; they are for the purpose of leading
away the gas, and are furnished with slides or valves, so that the gas may be
taken either from the top or bottom of the retort, as may be desired; j,j,
are flanged tubes for supporting the fuel within the retorts during the charging
operation; the tube of each retort is made in three sections, which fit the one
to the other.
To charge the gas retorts, the top covers are removed, and a bar suitably
suspended from above is introduced into the tube j, and this bar and the

page_text: 'interior of the tube are so formed that by turning the bar round after it has
been introduced a firm hold is obtained of the two upper sections of the tube;
the bottom cover is then removed, and the lowest section of the tube j falls out,
together with the coke supported by it; the bottom cover is then again closed
the upper sections of the tube with the remaining coke are allowed to descend,
the bar is removed, the space at the top of the retort is recharged, and the top
cover replaced.
;
In working the retorts and ovens care should be taken to distribute the
charging operations as much as possible, so that the retorts may not be
injuriously chilled. Retorts for the manufacture of gas may be set horizontally
in combination with the coke ovens so arranged to be charged at the top and
discharged at the bottom, as before dascribed; and I prefer to arrange the
said gas retorts so that their sides shall form a portion of the wall of the coke
oven, and the coal be distilled and carbonized by the heat of the coke ovens
and gases therefrom; retorts so set would be charged and drawn in the usual
way, the heat being kept up by the method before mentioned of working the
coke oven.
In employing horizontal gas retorts in this manner, I prefer to arrange
them one above another, and between two sets of vertical coke ovens con-
structed in the manner shown in the Drawings. Above and below each of
the gas retorts, I form a flue communicating with the coke ovens and with
the chimney; in this manner the retorts are heated on every side, and a
regular temperature is maintained. When it is desired to manufacture coke
without at the same time producing and collecting gas, I employ ovens of a
similar description to those before described to be used in conjunction with
gas retorts, viz., arranged so as to be charged at the top and discharged at the
bottom, and separated the one from the other by thin division walls, through
which the heat is communicated with considerable facility.
: The arrangement in this case may be very similar to that shown in the
Drawings, the gas retorts being modified to convert them into coke ovens, and
connections being made between such ovens and the surrounding flues. In
-working these ovens, I so arrange that when one of the ovens is charged with
fresh coal or fuel, the two adjacent-ovens shall be in full operation, that is to
say, with the material which they contain at a red heat throughout..
I would remark that I am aware that coke ovens and gas retorts have
before been set in combination in various ways; I only claim, therefore, the
combination of gas retorts with vertical or slightly inclined ovens, as herein
described.
Peat may be mixed with tar for fuel by taking the pieces of peat in the

page_text: form in which they are cut, but first dried, and immersing them in the tar;
and the peat so prepared may be used without further preparation. Also peat
prepared by immersion in tar, and afterwards baked in an oven or retort at
about 400° or 500°, without raising it to a red heat, is suitable for use as fuel
for many purposes for which unprepared peat cannot conveniently be employed.
As respects this part of my Invention, I would remark that I am aware that
a mixture of peat and tar or pitch has before the date of my Patent been in
some cases submitted to a process of destructive distillation in such manner
as to obtain an oil, and at the same time to produce a fuel, by coking the
mixture of peat with tar or pitch, I do not, therefore, claim the obtaining coke
from a mixture such as above mentioned; but I do claim the baking such a
mixture at a temperature lower than that necessary for coking, but sufficient
to drive off the volatile constituents of the tar or pitch.
In conducting the baking operation, I employ an iron oven such as is
sometimes used for baking other fuel, and it is connected with a condensor
to condense the portions of the tar volatilized by the heat.
When the peat is too dense for the tar thoroughly to penetrate it by simple
immersion, I force the tar, or a mixture of pitch and tar, or tar from which a
portion of the naptha or oil has been distilled, thoroughly into the peat, by
placing the peat in a closed vessel and pumping the bituminous matter into
it under sufficient pressure to accomplish the object. Pitch may be injected
into the peat in this way by heating the vessel so as to keep the pitch in a
fluid state. After the vessel has been filled and the pitch is in a fluid state,
I prefer to obtain the pressure necessary for injecting the pores of the peat by
pumping in tar, as that will not clog or interfere with the working of the
pumps.
In witness whereof, I, the said George Hinton Bovill, have hereunto set
my hand and seal, this Fourth day of February, in the year of our
Lord One thousand eight hundred and fifty-nine.
GEORGE HINTON BOVILL. (L.S.)
Witness,
HENRY WILLIAM CARPMAEL.