Improvements in or appertaining to Separating Oil from its Volatile Solvent.
Year: 1896

page_text: Date of Application, 7th July, 1896--Accepted, 15th Aug., 1896
COMPLETE SPECIFICATION.
Improvements in or appertaining to Separating Oil from its
Volatile Solvent.
A communication by GOTLIEB FREDERICK METZGER, of 61, McLean Street,
Cleveland, in the County of Cuyahoga and State of Ohio, United States of
America, Manufacturer."
1, GEORGE CECIL DYMOND, M.I.M.E., of the Firm of W. P. Thompson & Co.,
of 6, Lord Street, Liverpool and 6, Bank Street, Manchester both in the County
of Lancaster, 118, New Street, Birmingham in the County of Warwick and
322, High Holborn in the County of Middlesex, Patent Agent, do hereby declare
the nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
In the practice of the so-called naphtha process of producing linseed oil, the oil
is first extracted or dissolved out of the meal, in a percolator, by means of naphtha.
The next step in the process consists in separating the naphtha from the oil; and
it is to this step in the process that my present invention relates. The only method
for effecting this result, which heretofore has been practically successful, consists
in injecting live steam into the mixture in the separator tank, whereby the naphtha
is vaporized, and the naphtha vapor, as formed, is withdrawn from the separator
tank. While this method of effecting this result has been and is still practiced
commercially, it is objectionable for several reasons, the chief of which is that the
resulting oil has a peculiar rank taste and smell, probably due to the fact that a
permanent combination has been effected between the naphtha and a small quantity
(more or less) of the oil. This is due, as it is believed, to the extreme heat and
dryness of the live steam which is injected into the mixture. The hot steam
brought into direct contact with the oil globules, suddenly raises their temperature,
and some of the globules, it is believed, are broken and thereupon a permanent
combination between some of the naphtha and the oil released from said globules,
is effected. The live steam furnishes to the mixture very little,-certainly not
enough, moisture, or water, to protect the oil globules and prevent this action.
This theory may be wrong as to why the oil gets the taste and smell referred to,
but it is a fact that it does get it when live steam is used as described.
Another objection to the old method under consideration is that the resulting oil
contains a greater or less quantity of the glutinous impurity commonly known as
"foots." A small quantity of glutinous matter in the meal is probably dissolved
in the naphtha in the percolator. The extreme heat of the live steam, and the
absence of moisture, cause this glutinous matter to coagulate in the separator tank
as the naphtha is vaporized. The "foots" do not commonly appear in the oil when
it is first made, probably because the glutinous particles are so finely subdivided
that they are not visible; but after the oil has stood for awhile, these particles seem
to be attracted to each other, and become visible as an impurity. The peculiar
taste and smell of the oil heretofore produced by the naphtha process, and the
presence therein of the "foots," make the oil of less value commercially than the
oils which are produced by pressure; and these facts have also prevented
the successful use of the naphtha process for producing cotton seed oil or other
oils which are used as food products.
Another objection, which is of considerable practical importance, is the excessive
cost of the steam which must be used.

page_text: The objects of this invention are to produce a superior quality of oil, which is
devoid of any rank taste or smell, and which contains no "foots"; and to effect a
considerable saving in the cost of separating the naphtha from the oil; and with
these ends in view, the invention consists in the process hereinafter described and
claimed, that is to say,-in heating the mixture of oil and naphtha to the
temperature at which the naphtha will be vaporized, in injecting into the mixture
water heated to a temperature approximating that of the mixture, in mechanically
agitating the mixture, and in conducting away the vapor as it is formed.
This process may be practiced by a variety of apparatuses, but that which is
shown in the drawing is especially adapted for the use. It is especially contrived
with the following desirable objects in view, in addition to the complete separation
of the naphtha from the oil, riz., first, to effect a saving by its use, through utilizing
the exhaust from the steam coil in the separator tank, by which the mixture is
heated, for heating the water which is injected into the tank; second, to prevent
the loss of oil or naphtha in the event of the steam pipes becoming leaky; third, to
facilitate complete removal of the vapor as it is formed.
A part of the invention resides in the said apparatus, and consists in the
construction and combination of parts hereinafter described and claimed.
In the drawing
Figure 1 is a front elevation of the improved apparatus ;
Figure 2 is a sectional view of the combined safety and vacuum valve;
Figure 3 is a side elevation of said apparatus;
Figure 4 is a longitudinal vertical sectional view; and
Figure 5 is a transverse vertical sectional view on line -x of Figure 3.
The separator tank 1 is preferably made of sheet metal of a rectangular form;
it has an arch-shaped top 1b, in the center of which is a roll or supplemental arch 1,
of smaller diameter, which extends from one end of the tank to the other. Attached
to the inside of one side of said tank are the pipes 2, 2, closed at their inner ends
by plates 4, 4, thereby forming re-entrant chambers 3, 3. Man-holes, closed by
covers 5, are formed in the top of the tank; and a sight glass 6 is set into each end
near the top, so that the contents of the tank may be seen.
bottom of each end, is tightly closed by a door 7. The mixture of oil and naphtha
An opening, near the
to be separated is admitted to the tank through the pipe 9, having a valve 10.
A pipe 11 having a valve 12 is connected with the tank near one of the lower
front corners, and it is through this pipe that the remaining oil and water is drawn,
after the naphtha has been driven off. The tank rests upon any suitable blocking
in such manner that the corner to which the pipe 11 is connected shall be the lowest
point, thereby providing a natural drain. In the front of the tank 1 is an oil
glass 30 opening through pipes 31 into the interior of said tank, and provided with
à cock 32 at the bottom. Each pipe 31 has the valve 33 which may be closed, and
the contents of the oil glass 30 drawn off by opening the cock 32.
. A combined safety and vacuum valve 13 is secured to the top of the tank over
an opening therein, and is constructed as follows: It includes an external
cylinder 14 and a concentric internal cylinder 15, which is supported by means of
the lateral braces 16. A collar 17 is screwed onto the top of the cylinder 14, and
à pipe 27 which is fastened to this collar, may be connected with a tank, which is
not shown in the drawing. Inside of the pipe 27 is a cross bar 19 secured to the
tops of posts 18, which are in turn secured to the collar 17. A valve 21 is adapted
to fit the tops of the cylinders 14 and 15, and thereby close the entrance to the
space between them. This valve has a valve stem 21" which extends through an
opening in the plate 19, whereby said valve is guided. A coil spring 21 surrounding
the said valve stem thrusts end wise against said plate and valve, and thereby forces
the said valve 21 down upon its seat. In the middle of the valve 21 is an
opening, 21, through which communication is had with the interior of the
cylinder 15. A valve 24 is fitted to the lower end of the cylinder 15, and it is
connected by means of a coil spring with the valve 21. If the pressure in the
tank becomes too great, the valve 21 is lifted from its seat against the force of its

page_text: spring 21 and the vapor escapes from the tank through the space between the
cylinders 14 and 15. When a partial vacuum is formed in the tank, the valve 24
is automatically opened, and vapor from the pipe 27 passes into the tank through
the cylinder 15, and through the central opening in the valve 21. The use of a
combined safety and vacuum valve prevents any possible explosion or collapse of
the tank, by reason of too much or too little pressure therein. A pipe 28, having
a valve 29, which may be operated by hand, projects from the front of the tank,
near the top thereof, and is for the purpose of supplementing the action of the
combined safety and vacuum valve, if necessary. A hot water tank 35 is suitably
supported, preferably by brackets 34, which are secured to the tank. This water
tank has a thermometer 36 attached to one side, a safety valve 37 at the opposite
side, and a steam gauge 38 at the top. Inside of the tank 35 is a float 39 having a
graduated stem 40 projecting through a packed hole in the top of said tank, for the
purpose of indicating the height of water therein. The interior temperature of
the tank is registered by the thermometer, the pressure of steam therein gauged by
the gauge 38, while the valve 37 automatically relieves any excessive steam
pressure therein. A pipe 41 having a valve 42 supplies a regulated quantity of
water to said tank 35 during the vaporization of the naphtha. In the bottom of
the separator tank 1, resting upon any suitable supports, 'is a steam coil 45, having
sufficient capacity to heat the contents of said tank to a temperature at which the
naphtha and some of the water will be vaporized,-approximately 212° F.
A pipe 45 for supplying live steam to this eoil passes through the end of the
tank. The other end of the coil is connected by means of the pipe 46 with the
hot water tank 35. By reason of this construction, the exhaust steam from
the coil enters the tank 35 and thereby heats the water which is entering the
said tank 35 to the desired temperature, thus utilizing for this purpose the exhaust
steam which might otherwise be wasted. This construction also effects the result
of conducting and delivering into the hot water tank 35 (from which it will be
delivered into the tank 1) any oil or naphtha which may get into the steam coil
through any leaky joints therein. The described connection of the water tank 35
with the steam coil also provides a steam pressure therein, by means of which the
hot water is forced from said tank into the perforated spraying pipes 51, from
which it is sprayed into the contents of the separator tank 1. These pipes 51 are
supported within the tank, close above the steam coil and close to the agitators to
be presently explained. These pipes are connected by means of pipes 50 with the 1
bottom of the hot water tank.
Journalled within the tank are two shafts 53 which extend from one end of the
tank to the other, and through one end. Agitators consisting of disks 54 having
wings 55 are secured at intervals to the shafts 53 within the tank 1. The
pulleys 56 are fast to the ends of the shaft, which are outside of the tank and
are connected by the cross belt 57, while the pulley 58 which is fast on one of said
shafts furnishes the means by which both shafts are driven by the belt 59. The
two shafts are driven in opposite directions constantly during the process of
separating the naphtha from the oil, and they keep the contents of the tank in
constant agitation.
A trough 60 is suspended within the tank a little below the base of the
supplemental arch 1, and it extends to within a short distance of each end of
said tank. Near the ends of the trough are the pipes 61 which are secured to
the bottom thereof and extend therefrom downward and pass out through the
re-entrant chambers 3, being connected outside of the tank by drum 62 with a pipe
which conducts the vaporous and liquid naphtha and water to a suitable tank
(not shown). The vapor created within the tank rises to the top thereof, and is
then deflected downward into the trough, from whence it enters the pipes 61.
This trough not only catches the vapor, but it catches any condensation of the
vapor which may be formed in the supplemental arch in the top of the tank, and
thus prevents it from falling back into the tank, where it might check the
vaporizing action. The re-entraut chambers 3 which are open at their outer enda

page_text: serve to cool the horizontal section of the pipes 61, and thus assist in condensing
the vapor passing through the same, whereby it is more quickly reconverted into a
liquid state. Within each chamber 3 is a coupling 65 which connects the sections
of the horizontal portion of the pipe 61 and permits of the ready separation of the
same, for cleansing or other purposes.
Although the construction of all of the parts which go to make up the apparatus
have been described in detail, it is obvious that in many respects these details are
susceptible of change; and it is not intended that this patent shall be limited .to
the details of construction which are shown and described to any greater extent
than is particularly pointed out in the several claims.
In conducting the improved process with the described apparatus, the mixture
of oil and naphtha (or oil and any other volatile solvent which may have been
used for extracting oil,) is admitted to the tank through the pipe 9.
Steam is turned into the steam coil and the heating of the mixture begins. The
exhaust from the steam coil enters the hot water tank 35, whereby the water
therein is heated. When the contents of the separator tank 1 are heated to the
temperature at which the naphtha is vaporized, the valve in the pipe 50 is opened,
whereupon the hot water begins to be sprayed into the mixture from the
perforations in the pipe 51; at the same time the agitator shafts are set in
motion; and these several parts of the process are continued simultaneously until
all of the naphtha and a considerable quantity of the water which has been
sprayed into the mixture, has been vaporized and carried away through the
pipes 61.
By reason of the described connection of the hot water tank with the exhaust
from the steam coil, it is evident that the temperature of the water in said tank
will always be approximately the temperature of the mixture within the separator
tank 1. And thus, when said water is introduced into the tank 1, it does not
reduce the temperature and thereby check the evaporation, to any considerable
extent; nor does it suddenly heat the particles of the oil and naphtha with which
it comes in contact. It is a fact that this water is of a slightly lower temperature
than the contents of the tank, but since the water is injected in the form of a spray
into the mixture, and close to the heating coils, as shown, this water spray is
almost instantly raised to a temperature substantially equal to the temperature of
said mixture. When the operation of separating the naphtha from the oil has
been completed, nothing will flow through the pipe 61 but water. Thereupon the
steam is 'shut off from the steam coil, the water is shut off from the tank, and the
operation of the agitators is stopped. The mixture remaining in the tank will be
about 90 per cent. oil, and 10 per cent. water, more or less. And this mixture is
drawn off through pipe 11 to another tank,-not shown,-for final treatment.
One advantage of the described apparatus which may be here mentionel, is the
fact that it does not require to be constantly watched,-and in this respect it
differs from any apparatus heretofore used for separating naphtha from oil, by
injecting live steam into the mixture.
By employing the described process and apparatus, an oil is produced which is
sweet to the taste and smell, being devoid of the peculiar taste and smell which
has heretofore characterized oil produced by the naphtha process. The water
which has beeu injected into the tank has washed and cleansed the oil, thereby
making it unnecessary to effect this result by a subsequent operation. The oil
produced contains no "foots" or other impurities; and it is invariably much
lighter in color than the oil which has heretofore been produced by the naphtha
process. In fact, the oil produced by the described process is equal in every
respect to the so-called Calcutta oil produced by pressure from Calcutta seed.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me
by my foreign correspondent I declare that what I claim is :-
1. The herein described process of separating oil from its volatile solvent, which

page_text: consists in heating the mixture of oil and solvent to a temperature at which the
solvent will vaporize, in injecting hot water into said mixture, in mechanically
agitating the mass, and removing the resulting vapors until the vaporization of the
solvent is completed, substantially as and for the purpose specified.
2. In an apparatus for separating naphtha from oil, the combination of a
separator tank, having a vapor outlet, with a heating device, water pipes, and
mechanical agitators, all contained within said tank below the operative level of
the mixture therein, a hot water tank, connected with said water pipes, and means
for forcing hot water from said tank into and through said water pipes, substantially
as and for the purpose specified.
3. In an apparatus for separating naphtha from oil, the combination of a
separator tank having an oil and naphtha inlet, a vapor outlet, and an oil outlet,
with a steam coil, and one or more perforated spraying pipes within the tank, a
steam inlet pipe connected with said coil, a water tank connected by a pipe with
the outlet end of said coil, and a hot water pipe connecting said tank with said.
perforated pipes, substantially as and for the purpose specified.
4. In an apparatus for separating naphtha from oil, the combination of a tank
having an arch-shaped top, a trough suspended in the tank near said top, and one
or more vapor exit pipes connected with said trough and passing therefrom
downward and out of said tank, with means for heating the contents of the tank
to a temperature which will vaporize the naphtha, substantially as and for the
purpose specified.
5. In an apparatus for separating naphtha from oil, the combination of a tank
having an oil and naphtha inlet, and an oil outlet, with a steam coil, one or more
spraying pipes, and a trough, all within the tank, and vapor exit pipes leading
from said trough outside of said tank, a steam inlet pipe connected with said coil,
a water tank connected by a pipe with the outlet end of said coil, and a hot water
pipe connecting said tank with said spraying pipes, substantially as and for the
purpose specified.
6. In an apparatus for separating naphtha from oil, the combination of a tank
having an oil and naphtha inlet, a vapor outlet, and an oil outlet, with a steam
coil, and one or more spraying pipes, all within the tank, with steam outlet and
inlet pipes connected to opposite ends of said coil, a hot water pipe connected to
said spraying pipes, and means for forcing hot water through said pipes, and a
combined safety and vacuum valve connected with said tank, substantially as and
for the purpose specified.
Dated this 6th day of July 1896.
WM. P. THOMPSON & Co.,
Agents.