IMPROVEMENTS IN APPARATUS FOR EFFECTING THE REMOVAL OF TAR FROM THE HYDRAULIC MAIN IN THE MANUFACTURE OF ILLUMINATING GAS
Year: 1884

page_text: I, MAURICE SCHWAB of 96, Deansgate Manchester in the County of Lancaster,
Gas Engineer do hereby declare the nature of my invention for IMPROVEMENTS IN
APPARATUS FOR EFFECTING THE REMOVAL OF TAR FROM THE HYDRAULIC MAIN IN
THE MANUFACTURE OF ILLUMINATING GAS to be as follows:-
In the manufacture of gas the tarry products which are continually collecting in
the hydraulic main have from time to time to be drawn off in order to ensure the
proper working of the apparatus. While this drawing off taking place there is
considerable risk of explosion, for the tar having displaced the liquor contained in
the main, there is nothing, while the tar is running out, to seal the dip pipes, and
consequently the gas in the hydraulic main is free to return to the red hot retorts
unless great care is taken.
Now the chief object of the present invention is to provide simple apparatus
whereby the drawing off of the tarry products may be readily effected without
altering the dip level and thereby without the least risk of explosion. By the use
of this apparatus the additional advantage is obtained of being able to effect a
rinsing or washing out of the hydraulic main. The thickening of the tar therein is
thus prevented and a more valuable and useful tar is formed than that produced
under ordinary circumstances.
In carrying out this invention the hydraulic main is connected in any convenient
manner with a receiver or tank suitably placed at the side of the bench. This tank
is connected to a second closed receiver.
The first tank, or tank A forms a tar cistern in which the tar formed in the
hydraulic main accumulates. This tank as well as the hydraulic main is filled with
water to the proper level, and through the gradual but continuous formation of tar
the water is displaced and flows through an overflow pipe provided with a tap or
cock into the second receiver or tank B. In order to prevent escape of gas the pipe
is formed with a syphon.

page_text: The tank is calculated to hold the quantity of tar formed in a whole day's working,
and thus it will not be necessary so frequently as heretofore to draw off the tar.
The receiver B communicates with the opposite end, of the hydraulic main by a
pipe provided with a tap, and with the tank.A by a valve connection. When the
receiver B is filled with water, which will show itself by an overflow tap, the two
overflow taps are closed, the valve connection and the tap in the pipe connecting
tank B with the hydraulic main are opened. The tar descends now into the receiver B
and forces the water through the pipe back again into the hydraulic main.
During this discharge of tar the dip level remains unaltered, because the volumo
of liquid in the main is in no way altered. The valve connection is of larger
dimensions than the pipe and the tar acting like a plunger forces the water through
the entire length of the hydraulic main and serves to rinse or clear it out. At the
same time the water in the tank B prevents the tar running in faster than the
water runs out.
When the tank B is full, its connections are closed and the overflow taps opened.
The tar is drawn from the tank B by a suitable cock, and the apparatus is again
ready for working.
Means are provided for ascertaining the height of the liquid in the tank A, and
for filling up the tank B if required. For cooling the tank A and the tar contained
therein the tank may be surrounded by a jacket in connection with a water
condenser, or a condenser can be fixed internally. By proper condensation the tar
can be kept permanently at such a temperature that it will flow readily.
The condensing or cooling apparatus is not described; as any suitable or known
arrangement will serve the purpose.
If it is desirable to completely renew the liquid in the main without interfering
in its work, a tube can be attached to the overflow tap of the tank B reaching into
a vessel filled with fresh water. The receiver B will thus fill itself by sucking in
the fresh water as the tar is running out. In this case the displaced water running
from the hydraulic main into the overflow pipe during formation of tar, is allowed
to flow away.
The receiver B may be placed higher than the hydraulic main, but in that case
the discharge of tar into the receiver B has to be effected by a pump.
Dated this 21st day of April 1884

page_text: I MAURICE SCHWAB of 96 Deansgate, Manchester in the County of Lancaster,
Gas Engineer do hereby declare the nature of my invention for "IMPROVEMENTS
IN APPARATUS FOR EFFECTING THE REMOVAL OF TAR FROM THE HYDRAULIC MAIN
IN THE MANUFACTURE OF ILLUMINATING GAS," and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement :-
In the manufacture of gas the tarry products which are continually collecting in
the hydraulic main have from time to time to be drawn off in order to ensure the
proper working of the apparatus. While this drawing off is taking place there is
considerable risk of explosion because the tar having displaced the liquor or water
in the main there is nothing, while the tar is running out of the main to seal the
dip pipes and consequently any gas in the hydraulic main or other parts in free
communication with the main, can return to the red hot retorts where it is liable
to explode unless great care is taken.
Now the chief object of the present invention is to provide simple apparatus
whereby the drawing off of the tarry products may be readily effected without
altering the dip level and thereby without the least risk of explosion. By the use
of this apparatus the additional advantage is obtained of being able to effect a
rinsing or washing out of the hydraulic main, the thickening of the tar therein is
thus prevented and a more valuable and useful tar is formed than that produced
under ordinary circumstances.
In the accompanying drawing Fig: 1 is a front view partly in section of a retort
setting, with the invention applied thereto and
Fig 2 is a side elevation of the tar tank or receiver.
V is the hydraulic main which is connected in any convenient manner with a
receiver or tank A suitably placed at the side of the bench. This tank A is
connected to a second closed receiver B. The tank A forms a tar cistern in which
the tar formed in the hydraulic main V accumulates. This tank A, as well as the
hydraulic main V, is first filled with water to the proper level, as shown by the
dotted lines Fig: 1 and through the gradual but continuous formation of tar this
water is displaced and flows through an overflow pipe O provided with a tap or
cock C into the second receiver or tank B. In order to prevent escape of gas the
pipe O is formed with a bend o which becoming full of water acts as a seal.
The tank A is calculated to hold the quantity of tar formed in a whole day's
working, and thus it will not be necessary so frequently as heretofore to draw
the tar.
The receiver B communicates with the opposite end of the hydraulic main V by
a pipe P which is provided with a tap E and with the tank A by a valve con-
nection D of any suitable construction. When the receiver B is filled with the
water from the receiver A; which will show itself by means of an overflow tap b,
the two taps b and C are closed. The valve connection D and the tap E in the
pipe P, connecting tank B with the opposite end of the hydraulic main, are opened.
The tar descends now into the receiver B and forces the water through the pipe P
back again into the hydraulic main V. During this discharge of tar the dip level
in the hydraulic main will remain unaltered because the volume of liquid in the
main is in no way altered, that is to say as the tar runs out from A into B the
water from B enters the hydraulic main. The valve connection D is of larger
dimensions than the pipe P, and the tar by reason of its greater weight acts like

page_text: i
a plunger and causes the water from the receiver to rush into the hydraulic main
with considerable force and thus serves to rinse or clean out the main. At the
same time the resistance of the water in the tank B prevents the tar running in
faster than the water runs out.
When the tank B is full of tar the valve connection D and the tap E are closed,
and the overflow taps b and C are opened. The tar is then drawn from the tank B
by a suitable cock & and the apparatus is again ready for working. Taps may be
provided for ascertaining the height of the liquid in the tank A, and a funnel i
with a tap, is employed for filling up the tank B with water as required. For
cooling the tank A and the tar contained therein, the tank may be surrounded by
a jacket in connection with a water condenser or a coudenser can be fixed
internally. By proper condensation the tar can be kept permanently at such
a temperature that it will flow readily.
The condensing or cooling apparatus is not described, as any suitable or known
arrangement will serve the purpose. If it is desirable to completely renew the
liquid in the main without,interferring with the working of the apparatus a tube can
be attached to the overflow tap b of the tank B reaching into a vessel filled with
fresh water. The receiver B will thus fill itself by sucking in the fresh water as the
tar is iunning out. In, this case the displaced water running from the hydraulic
main into the overflow pipe o during formation of tar is allowed to flow away.
The receiver B may be placed higher than the hydraulic main but in that case
the discharge of tar into the receiver B has to be effected by a pump.
The above described arrangement of apparatus has the additional advantage of
preventing the admission of air during the operation of drawing off the tar.
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed I declare that what
I claim is
1st The means substantially as herein shown and described for maintaining a
liquid seal to the dip pipes in the hydraulic main during the drawing off of the tar
as and for the purpose set forth.
2nd The combination of the hydraulic main and tar tank, as A, with a receiver,
as B, to receive the overflow water from the hydraulic main, and from which said
water is forced by the inflow of tar to effect a rinsing or washing out of the
hydraulic main as set forth.
3rd The combination of the hydraulic main with a tar tank as A a receiver as B
and suitable connections whereby the tar can be drawn off from the hydraulic main
without the admission of air thereto as set forth.
4th The combination of a condenser with the apparatus for drawing off the tar
from the hydraulic main substantially as herein described.