IMPROVEMENTS IN OBTAINING PRODUCTS FROM ROCK OIL, COAL, COAL TAB, AND OTHER LIKE MINERAL SUBSTANCES, IN A MORE OR LESS PURE AND DEODORIZED STATE, AND IN THE APPARATUS TO BE USED THEREFOR, AND WHICH IS ALSO APPLICABLE TO DISTILLATION IN GENERAL
Year: 1862

page_text: LETTERS PATENT to Elijah Freeman Prentiss, of Birkenhead, in the
County of Chester, Chemist, and Robert Adam Robertson, of Liverpool,
in the County of Lancaster, Brewers and Distillers' Engineer, for the
Invention of "IMPROVEMENTS IN OBTAINING PRODUCTS FROM ROCK OIL, COAL,
COAL TAB, AND OTHER LIKE MINERAL SUBSTANCES, IN A MORE OR LESS PURE AND
DEODORIZED STATE, AND IN THE APPARATUS TO BE USED THEREFOR, AND WHICH
IS ALSO APPLICABLE TO DISTILLATION IN GENERAL."
Sealed the 28rd January 1868, and dated the 81st July 1862.
PROVISIONAL SPECIFICATION left by the said Elijah Freeman Prentiss
and Robert Adam Robertson at the Office of the Commissioners of
Patents; with their Petition, on the 31st July 1862.
We, ELIJAH FREEMAN PRENTISS, of Birkenhead, in the County of Chester,
Chemist, and ROBERT ADAM ROBERTSON, of Liverpool, in the County of
Lancaster, Brewers and Distillers' Engineer, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN OBTAINING PRODUCTS FROM ROCK OIL,
COAL, COAL TAE, AND OTHER LIKE MINERAL SUBSTANCES IN A MORE OR LESS PURE
AND DEODORIZED STATE, AND IN THE APPARATUS TO BE USED THEREFOE, AND WHICH
IS ALSO APPLICABLE TO DISTILLATION IN GENERAL," to be as follows (that is to
say)
This Invention consists in a peculiar system for distilling and treating rock oil,
coal, coal tar, and other like mineral substances for obtaining products there-

page_text: from in a more or less deodorized and pure condition, and in separating and
obtaining various products that are condensable at various degrees of tempe
rature as they pass from the evaporating vessel, and in the apparatus to be
used therefor, which is also applicable to distillation in general.
The evaporating vessel into which the rock oil or other substanco to be
operated upon is placed, may consist of a cylindrical dome-topped vessel with a
flat bottom, having one, two, or more annular recesses formed therein, and
which it is preferred to form in two parts, attached together by an hori-
zontal joint for the convenience of access to the interior for the purpose of
cleaning or repairing. This evaporating vessel is enclosed within an outer
casing or jacket, having a similar contour, but of larger capacity, and is con-
structed with a circular opening in the centre of the bottom, and annular feathers
which project upwards into the centre, and within a short distance of the top
of the annular recesses in the bottom of the evaporating vessel. The top of the
outer casing is provided with a flue for the escape of the products of combus-
tiou. The heat is applied to the bottom of the vessel through the circular
opening in the bottom of the outer casing, the draught passing in an up-and-
down direction through the annular recesses in the bottom of the vessel, and
up the vertical side and over the dome top thereof, and out at the flue on the
crown of the outer casing. The evaporating vessel is provided with a self-
acting instrument for ascertaining the temperature within the vessel, and for
controlling the action of the heat thereon, and consists of a hollow sphere, or
other suitably shaped air vessel-placed within the evaporating vessel, and com-
municating by a pipe with the interior of a small gasometer on the outside of
the evaporating vessel, the lower edge of the dome top of which works in mer-
cury, or other suitable fluid, the, rising and falling of the dome top actuating a
throttle valve damper or other mechanical equivalent through a lever or other
suitable substitute. In some cases it is proposed to divide the interior of the
evaporating vessel into several compartments, and to pass the material to be
acted upon through them in succession. In some cases it is preferred to sub-
stitute a steam, hot water, or air jacket for the external casing described, or to
use steam, water, or air introduced through a coil of pipes placed inside the vessel,
and in others dry or moist loose steam in immediate contact with the material
to be operated upon. The evaporating vessel is connected to a separator or
condenser by a pipe passing through the side of an evaporating vessel, by
preference passing out of the side thereof at a point below the surface of the
material being operated upon. This pipe extends inwards and upwards above
the surface of the material within the evaporating vessel, and is formed with a
trumpet mouth. The lower end of this pipe opens into the bottom of the first

page_text: separator or condenser, which consists of a number of pipes placed parallel to
each other, open at each end, and pass through a plate at each end, and
which are again surrounded by a square or other suitably shaped box casing,
a little longer than the pipes, so as to form a small air-tight chamber at each
end of the pipes, water, air, or other cooling medea being circulated around the
exterior of the pipes between the two face plates to which they are fixed. The
products of evaporation pass into the lower chamber, which is divided into
two, three, or more compartments, passes up the first set of pipes into the first.
compartment of the upper chamber, and down the second series of pipes into
the second compartment of the lower chamber, and up through the third
series of pipes into the second compartment of the upper chamber, and down
through the next series of pipes into the next compartment of the lower
chamber, and so on to any required extent, but in most cases it is preferred
to construct the separators or condensers so as to only carry the fluids up and
-down the pipes about three times, and then to connect the last compartment
of the lower chamber by a pipe or passage to the first compartment of the
lower chamber of a second separator or condenser of a similar construction
, some little distance from the first, and so on through any required number of
-separators or condensers, and thence through a common worm condenser fitted
at the bottom with a close receiver or draw-off cock. The bottom of the
worm communicates by a pipe with the interior of the gasometer, into which all
the uncondensed vapour is received. Some of the separators or condensers
are fitted with a drawer or drawers having wire gauze bottoms, in which are
deposited the deodorizing, purifying, flavoring, or scenting substances, the
drawers on the front being made air-tight. Each compartment of the lower
chamber of the separators or condensers is provided with a'draw-off cock for
discharging the various products of distillation, and it is preferred to form an
air chamber around, or partially around the whole series of pipes, and to
insert horizontal air pipes between each series of vertical pipes, which air
pipes are open at each end into the air chamber for the purpose of equalizing
the temperature of the condenser, and supplying a body of air. to actuate a
valve to regulate the supply of the cooling medium. It is preferred to fit the
-tops and bottoms of the outer casing of the condensers so that they can bo
removed for the purpose of cleaning the pipes and compartments of the upper
and lower chambers.
It will be readily seen that this apparatus herein-before described is appli-
cable for the purposes of distillation in general.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Elijah Freeman Prentiss and Robert Adam Robertson in the
Great Seal Patent Office on the 30th January 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ELIJAH
FREEMAN PRENTISS, of Birkenhead, in the County, of Chester, Chemist, and
ROBERT ADAM ROBERTSON, of Liverpool, in the County of Lancaster, Brewers
and Distillers' Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirty-first day of July, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Elijah Freeman Prentiss and Robert Adam Robertson, Her special
licence, that we, the said Elijah Freeman Prentiss' and Robert Adam Robert-
son, our executors, administrators, and assigns, or such others as we, the
said Elijah Freeman Prentiss and Robert Adam Robertson, our 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 ex-
pressed, 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 OBTAINING PRODUCTS FROM ROCK
OIL, COAL, COAL TAR, AND OTHER LIKE MINERAL SUBSTANCES, IN A MORE OR LESS
PURE AND DEODORIZED STATE, AND IN THE APPARATUS TO BE USED THERETOR,
WHICH IS ALSO APPLICABLE TO DISTILLATION IN GENERAL," upon the condition
(amongst others), that we, the said Elijah Freeman Prentiss, and Robert
Adam Robertson, our executors or administrators, by an instrument in writing
under our, 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 we, the said Elijah Freeman Prentiss and Robert
Adam Robertson, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement (that is to say):-
This our said Invention consists in a peculiar system for distilling and
treating rock oil, coal, coal tar, and other like mineral substances, for obtaining
products therefrom in a more or less deodorized and pure condition, and m

page_text: seperating and obtaining various products that are condensable at various
degrees of temperature as they pass from the evaporating vessel, and in the
apparatus to be used therefor, which is also applicable to distillation in general.
The evaporating vessel into which the rock oil or other substance to be operate
upon is placed, may consist of a cylindrical dome topped vessel, with a flat
bottom, having one, two, or more annular recesses formed therein, and which
it is preferred to form in two parts, attached together by an horizontal joint,
for convenience of access to the interior, for the purpose of cleaning, or
repairing. This evaporating vessel we enclose within an outer casing, or
jacket, having a similar contour, but of larger capacity, and constructed with a
circular opening in the centre of the bottom, and annular feathers which
project upwards into the centre and within a short distance of the annular
recesses in the bottom of the evaporating vessel. The top of the outer
casing we provide with a flue for the escape of the products of combustion.
The heat we apply to the bottom of the vessel through the circular opening in
the bottom of the outer casing, the draught passing in an up and down
direction through the annular recesses in the bottom of the vessel, and up the
vertical side and over the dome top thereof, and out at the flue on the crown
of the outer casing. The evaporating vessel we provide with a self-acting
instrument for ascertaining the temperature within the vessel, and for con-
trolling the action of the heat thereon, and which consists of a hollow sphere,
or other suitably shaped air vessel placed within the evaporating vessel, and
communicating by a pipe with the interior of a small gasometer on the outside
of the evaporating vessel. The lower edge of the dome top of the gasometer,
works in mercury or other suitable fluid. The rising and falling of the dome
top actuates a throttle valve, damper, or other mechanical equivalent, through
a lever or other suitable substitute. In some cases it is proposed to divide
the interior of the evaporating vessel into several compartments, and to pass
the material to be acted upon through them in succession. In some cases we
prefer to substitute a steam, hot water, or air jacket, for the external casing
described, or to use steam, water, or air introduced through a coil of pipes
placed inside the vessel, and in others dry or moist loose steam, in immediate
contact with the material to. be operated upon. The evaporating vessel wo
connect to a seperator or condenser by a pipe passing through the side of the
evaporating vessel, by preference passing out of the, side thereof at a point
below the surface of the material being operated. upon. This pipe extends
inwards and upwards above the surface of the material within the evaporating
vessel, and is formed with a trumpet mouth. The lower end of this pipe opens
into the bottom of the first seperator or condenser, which consists of a number

page_text: .
of pipes placed parallel to each other, open at each end, and pass through a plate
at each end, and which are again surrounded by a square or other suitably
shaped box casing, a little longer than the pipes, so as to form a small air-tight
chamber at each end of the pipes, water, air, or other cooling medea being
circulated around the exterior of the pipes between the two face plates to
which they are fixed. The products of evaporation pass into the lower chamber,
which is divided into two, three, or 'more compartments, passes up the first set
of pipes into the first compartment of the upper chamber, and down the second
series of pipes into the second compartment of the lower chamber, and up
through the third series of pipes into the second compartment of the upper
chamber, and down through the next series of pipes into the next compartment
of the lower chamber, and so on to any required extent, but in most cases it is:
preferred to construct the seperators, or condensers, so as to carry the fluids:
up and down the pipes only about three times, and then to connect the last>
compartment of the lower chamber by a pipe or passage, to the first com-
partment of the lower chamber of a second seperator or condenser of a similar
construction, placed some little distance from the first, and so on through any
required number of seperators, or condensers, and thence through a common
worm condenser, fitted at the bottom with a close receiver, having a draw-off
cock. The bottom of the worm, or the chamber in which it opens, communi-
cates by a pipe with the interior of a gasometer, into which all the uncondensed
vapour is received. Some of the -seperators, or condensers are fitted with a
drawer or drawers, having wire gauze bottoms, in which is deposited the
deodorizing, purifying, flavoring, or scenting substances. These drawers are
made air-tight on the front. Each compartment of the lower chamber of the
seperators or condensers we provide with a draw-off cock, for discharging the
various products of distillation, And we prefer to form an air chamber around
or partially around the whole series of pipes, and to insert horizontal air pipes
between each series of vertical pipes; which air pipes are open at each ond
into the external atmosphere, or air chambers, for the purpose of equalising
the temperature of the condensers, and supplying a body of air to actuate a
valve to regulate the supply of the cooling medium. We prefer to fit the tops
and bottoms of the outer casing of the condensers, so that they can be removed
for the purpose of cleaning the pipes, and compartments of the upper and
lower chambers. It will be readily seen that this apparatus, herein-before
described, is applicable for the purposes of distillation in general.
That this our said Invention may be the more readily seen and understood,
we have hereunto annexed sectional Drawings of so much of ono modification
of our apparatus as will be necessary to illustrate the practical application of

page_text: the Invention. Like letters and figures. marked on the Drawings are used to:
indicate similar parts..
Figure 1 is a sectional vertical elevation of one of our improved stills with
self-acting draught regulating damper, in combination with a set of three of
our improved compound condensers; the second and third being shown without
their enclosing air-tight casing herein-before described, and the first is shown,
with an internal air vessel for working the valve regulating the supply of.
liquid surrounding the pipes, and the common. still worm, with the addition,
of a receiving chamber to receive the products last condensed, and any uncon-
densable gas that may remain, which is conveyed therefrom by a pipe to the.
gasometer, also seen in section. Figure 2 is an horizontal section of the still;
or evaporating vessel taken from a to b, Figure 1, and Figure 3 is a horizontal
section of the second condenser, taken from c.to d. The dotted lines round;
this Figure show the position of the air-tight casing, which in some instances
it is preferred to enclose the condensers; the expansion or contraction of the,
air being used as a motive power to actuate the valve for regulating the
temperature of the cooling liquid surrounding the vertical condensing pipes.
These casings need not be applied to all the condensers, as the transverse.
vertical air pipes, open to the atmosphere at each end, will be found to
have a considerable influence in equalising the temperature of the con-;
densers.
A is the interior shell of the still or evaporating vessel, which is enclosed.
within B, an outer jacket, forming a passage for the products of combustion.
which escape by C, the smoke pipe, which is fitted with D, a throttle damper,
which is connected by E, levers to the top of the dome of F, a gasometer,.
connected by G a pipe, opening into the interior of H, a spherical air vessel,.
placed in the interior of the evaporating vessel; 1, the vapour pipe, connecting
the evaporating vessel with J' the first condenser; in the interior of which is
placed K, a cylindrical egg-ended air vessel, which by L a pipe (seen broken
off) is connected with a second gasometer, (like the one seen on the evaporating
vessel, which actuates the valve regulating the supply of M, liquid or vapour,
surrounding N, the condensing pipes, through which the vapour from tho
evaporating vessel passes in the direction indicated by the arrows. P face
plates, through which the ends of the. pipes (N) open into the upper, and
lower chambers of the condensers. Q, vertical diaphragm, by which the
cavities on the top and bottom of the condensers are divided into seperate
chambers. R is a hollow vessel, used to hold hot water, hot air, or steam, to
heat the liquid surrounding the condensing pipes (N,) in the first condenser,
to be used previous to setting the apparatus to work, for the purpose of pre-

page_text: venting a too rapid condensation in the first condenser, which can be heated to
any degree below that of the evaporating vessel. S, the outer casing of the
condensers, through which pass .T .and T', supply and outlet pipes for the
passage of the liquid surrounding the vertical pipes (N). U,.chambers on the
bottoin of the condensers to supply cooling or heating medea to the bottom
of the chambers into which the various products of combustion fall, and which
are fitted with u and u¹ inlet and outlet pipes; V, pipes connecting the various
condensers; W a .common. worm condenser, but having connected to the
bottom-thereof X, a receiving chamber for receiving the last liquid products
of distillation, and any uncondensed vapour which passes off by Y, a pipe,
into Z, a gasometer; e air pipes, which pass horizontally through the con-
densers, and open at each end into the atmosphere, or into the surrounding
air-tight casing described when that modification is used; f, f, f, fƒƒ
ff, and f, cocks, by which the various products of distillation are drawn
off from their several receiving chambers.
In the modification here described, a set of three of our improved condensers
are shown, but it will be readily seen that these may be increased to any desired
number. And the self-acting valve-motion may be worked by the air enclosed
within the air-tight casing surrounding the condensers when it is desirable so
to fit them. And in some cases, we prefer to use the expansive force of
mercury, in place of air, for the purpose of actuating the throttle valve damper
and also in the regulating apparatus described, as applied to the first con-
denser.
·
Having now fully described, and ascertained the nature of this our said
Invention, and how we believe the same may be best carried into practical
effect, we wish it to be understood that we do not confine ourselves to the
precise details, relative size, or proportions of the various parts of the apparatus
but what we do claim is,-
"
"
First, seperating the various products of distillation that are condensable at
various temperatures at one operation, as herein-before described and set forth,
or any mere modification of the same.
Secondly, constructing the inner end of the vapour pipe within the evapo-
rating vessel vertically, and carrying the same horizontally out through the
side of the vessel, at a point at or below the surface of the matérial, being
operated upon, as herein-before described and set forth, or any mere modifica-
tion of the same.
Thirdly, the peculiar arrangement of self-acting apparatus for actuating the
throttle valve of flue dampers, herein-before described or any mero modification
of the same

page_text: Fourthly, the use of an internal cylinder within the body of the condensers,
in combination with and for actuating the valve regulating the flow of cooling
liquid surrounding the vertical condensing pipes herein-before described, or
any mere modification of the same.
Fifthly, the peculiar arrangement herein-before described and set forth, for
heating the medea surrounding the condensing pipes, so as to regulate the
amount of condensation taking place in the first portion of the condensers.
Sixthly, the use of air pipes, for equalising the temperature of the condensers,
as herein-before described, or any mere modification of the same.
Seventhly, surrounding or enclosing the condensers within an air-tight casing
and applying the elastic power of the enclosed air to actuate the valves regu-
lating the flow of the cooling meden.
And, lastly, the general arrangement, combination, construction, and im-
proved system of apparatus herein-before described and set forth, for obtaining
various products from rock oil, coal, coal tar, and other like mineral substances,
in a more or less pure and deodorized state, at one operation, and for the
purposes of distillation in general.
In witness whereof, we, the said Elijah Freeman Prentiss, and Robert
Adam Robertson, have hereunto set our hands, and affixed our seals,
this Twenty-ninth day of January, in the year of our Lord One
thousand eight hundred and sixty-three.
Witness,
WILLIAM WALKER,
ELIJAH FREEMAN (L.s.) PRENTISS.
ROBERT ADAM
44, Castle Street,
(L.B.) ROBERTSON.
Liverpool.