and Apparatus for Separating and otherwise Treating Oils and like Liquids.
Year: 1895

page_text: Date of Application; 16th Sept., 1895
PROVISIONAL SPECIFICATION.
Process and Apparatus for Separating and otherwise Treating Oils
and like Liquids.
I, GEORGE MITCHELL of 47 Victoria Street, Westminster, in the County of
London, Consulting Engineer, do hereby declare the nature of this invention to
be as follows:-
This invention relates to the treatment of oils and like liquids, and consists of a
process and apparatus for the removal of impurities of that description which are,
at ordinary temperatures, of the same specific gravity as the oil itself, but at a
certain increase of temperature attain a lower or higher specific gravity than the
oil and are therefore capable of being separated from it by gravity methods.
The process consists in submitting the impure oil to the action of a vacuum in a
syphon shaped apparatus, in such manner that the oil is drawn upwards as soon
as it separates from the impurities, when the latter under the influence of heat,
attain a different specific gravity from the oil, the latter flowing off purified.
The apparatus employed in carrying this process into effect consists of a cylin-
drical or other shaped tube or chainber preferably encased or surrounded by a steam
jacket for the purpose of heating it to the desired degree; but any other convenient
and suitable means of heating the tube and its contents may be employed. The
tube or chamber has a number of hollow truncated cone-shaped tubes or shells
arranged one above the other inside it with the smaller ends downwards.
This tube or chamber forms the ascending side of a syphon, the descending side
of which is carried down far enough to ensure the outflow of the purified oil; and
this is secured by continuing it downwards to a point below that at which the
impure oil is fed into the ascending side of the tube or chamber. To the top of
the tube or chamber is attached a pipe which connects it with a vacuum vessel or
air pump and this latter is arranged at such a height above the oil tube or chamber,
that not even a perfect vacuum in the former can lift the oil to its level.
The action is as follows:-
The impure oil is poured in through a funnel or other device situate near the
bottom of the ascending side of the syphon tube or chamber, and this latter being :
heated by any convenient means to the desired temperature, either the oil is expanded
and becomes consequently of lesser specific gravity than the impurities contained
therein, or the impurities become dense and consequently of greater specific gravity
than the oil. In either case the action of the vacuum draws up the lighter oil and
leaves behind the heavier impurities; and this action is assisted by the conical tubes
or shells, which by reason of their shape cause the lighter purified oil to pass up
outside them, and allow the heavier impurities to fall back upon their interior
surfaces, pass inwards, and fall inside then to the bottom of the tube. The purified
oil passes over the top, down the descending tube of the syphon, and flows out; the
impurities settle at the bottom of the ascending side of the syphon and are drawn off
and collected at intervals.
The steam for heating is supplied to the jacket from a boiler or other convenient
source, and I sometimes arrange a cock in such manner that the steam may be
turned into the lower part of the ascending side of the tube so as to disturb
:

page_text: any impurities which may collect there. Or this may be done by admitting a supply
of hot water from a condensed water tank.
Dated this 16th day of September 1895.
WILLIAM J. MUNDEN,
106 Priory Park Road, Kilburn, London, N.W.,
Agent for the Applicant.
Process and Apparatus for Separating and otherwise Treating Oils
and like Liquids.
I, GEORGE MITCHELL, of 47 Victoria Street, Westminster, in the County of
London, Consulting Engineer, 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:-
This invention relates to the treatment of oils and like liquids, and consists of a
process and apparatus for the removal of, (a) solid impurities of that description
which are, at ordinary temperatures held suspended in the oil by its viscosity, and
in which the difference of specific gravity between the oil and such matter is not
sufficient to allow free precipitation, (b) liquid impurities, i.e. natural and added
moisture to free the oil from which under ordinary circumstances an amount of heat
is required which is detrimental to the oil.
The process consists in submitting the impure oil in the form of a column
suspended by a vacuum to a slight rise of temperature; at the circumference the oil
(which is susceptible of considerable change of volume with a small increase of
heat) tends to rise upwards and the solid impurities are pushed towards the centre
of the column. In consequence of this movement there is set up an upward current
of oil round the circumference of the column and a downward current of solid
impurities in the centre of the column. At the top of the column the oil will be
practically freed from solid impurities and at this point the residual moisture is
dissipated into the vacuum, the pure oil being taken down a pipe and drawn off at
a level lower than the length of column supported by the vacuum.
The apparatus employed in carrying this process into effect consists of a cylindrical
or other shaped tube or chambers preferably encased or surrounded by a steam
jacket for the purpose of heating it to the desired degree; but any other convenient
and suitable means of heating the tube and its contents may be employed. The
tube or chamber has a number of hollow truncated cone-shaped tubes or shells
arranged one above the other inside it with the smaller ends downwards.
This tube or chamber forms the ascending side of a siphon, the descending
side of which is carried down far enough to ensure the outflow of the purified
oil and this is secured by continuing it downwards to a point below that at
which the impure oil is fed into the ascending side of the tube or chamber. To the
top of the tube or chamber is attached a pipe which connects it with a vacuum
vessel or air pump and this latter is arranged at such a height above the oil tube or
chamber that not even a perfect vacuum in the former can lift the oil to its level.
In order that my invention may be fully understood and ascertained, I append
drawings in which :-
Fig. 1 is an elevation (partly in section) of an apparatus according to my
invention.
Fig. 2 is a section of the upper end of same.
Fig. 3 is a diagrammatic representation of a simple form of apparatus, illustrating
the principle.
Fig. 4 is a vertical section of part of the receiver or chamber.
Fig. 5 is a horizontal section of same.

page_text: Fig. is a vertical section of a modified form or chamber.
Fig. 7 is a vertical section, and
Fig. 8 is a plan of a cup or shell as used.
9
a indicates a hollow vertical cylinder which forms a receiver or chamber in
which the treatment is carried on, and it is surrounded by an outside casing,
he annular space d between the two serving to contain steam, water, or other fluid,
r liquid which is used for the purpose of raising or lowering the temperature of
he chamber a and its contents. The fluid or liquid used for this purpose is admitted
y a pipe e, and the fluid or a liquid condensed from the same may be 'allowed to
pass out through the drain pipe f, which enters the space d through the lower of
two conical ends b serving as covers for the chamber a and its jacket d.
A vertical tube k is screwed into the lower end of the chamber a, and through this
any impurities which may collect in the lower part of the chamber a can be with-
drawn, a cock being used for the purpose of controlling this withdrawal.
A tube is screwed into the upper cover b and establishes communication between
the chamber a aud the interior of a receiver which serves to collect the moisture
extracted from the oil during the process. The tube g must have a minimum length
sufficient to ensure that the air pressure acting below the ascending column of oil
can never lift the latter to the top of the receiver r, and in the lower part of this
vessel is fixed a drain pipes by which the moisture extracted can flow into a
suitable receptacle. This drain pipes is preferably trapped, though this is not
essential. From the top of the receiver a tubet passes to a vacuum vessel or
From a
pump, by which a vacuum is established and maintained in the receiver r.
point near the top of the chamber a a tube o is carried out at right angles and bent
downwards to form the descending side of the siphon, and this tube is continued
downwards to a point below that at which a pipe enters the chamber a and
serves to convey oil from the oil supply cistern m to the interior of the chamber a.
The pipe has a cock or valve fixed at a convenient height by means of which the
inflow of oil to the vessel a can be controlled.
In some cases I employ a hot water cistern and connect its interior with the
bottom of the chamber a by means of a pipe i, and by this means I am enabled to
admit water for the purpose of washing out or agitating any impurities which may
have collected in the interior of the chamber a. The drain pipe ƒ may pass to an
automatic trap g which communicates with the cistern h; and by inserting a short
piece of pipe and a cuck j hetween the pipes f and i, I can at will turn the steam
or water from the annular jacket d into the lower part of the interior of the
chamber a for the same purpose. One or more gauge glasses n are employed to
indicate the level of the oil.
Inside the chamber a are disposed a number of hollow truncated cone-shaped
shells or tubes p preferably disposed as shewn in Fig. 4 with the smaller ends
downwards. These are attached to the inside vessel a in any convenient manner so
as to leave an annular space between the larger ends and the wall of the chamber a
and their smaller ends are open; any convenient number of these may be
employed.
When the chamber a is surrounded by a cooling fluid, it is found to be an advan-
tage to have the cones disposed in the manner shewn in Fig. 6.
The principle of the action is best shown in Fig. 3 in which a diagrammatic view
is given of a siphon. A vacuum being produced in the tube 7, and oil being
admitted at and the tube heated, the oil is drawn up until it can enter the pipe o
the mouth of which is continued below the point l. Thus a continuous flow is
produced while the vacuum draws the lighter impurities up into the pipe q.
The operation is as follows:-
The cock k¹ is closed and oil is admitted by the pipe 1; the vacuum pump or
vessel is then placed in communication with the vessel a and the oil allowed to fill
the apparatus until it reaches nearly to the opening of the pipe o; this being
indicated by the upper gauge glass n. The heating or cooling fluid is next supplied
to the jacket d; and after allowing the oil to circulate for some time the height of

page_text: the column is increased until it commences to flow from the outlet pipe o; should
the stream not be of sufficient purity the column is again reduced and the oil allowed
to circulate for a longer period. After the machine has once been started it is only
necessary to regulate the rate of outflow. at o to, obtain the required purity, the
inlet remaining full open. After working some time the cock k¹ is opened and the
impurities allowed to run out. This cock may either be allowed to remain partly
open or it may be opened at intervals; and should the material be of uniform
quality, and the vacuum be maintained the cocks k' and o' may be so regulated that
the operation becomes automatic.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. The process of separating and treating oils and like liquids which consists in
feeding the impure oil or the like into the ascending leg of a heated siphon up which
it is drawn by ET vacuum created at its top in such manner that the impurities
contained in the oil are either reduced to a less specific gravity than the oil and are
consequently drawn up out of it, or the oil assumes a less specific gravity than the
impurities which are deposited at the bottom of the containing vessel, while the
purified oil passes over into the descending leg of the siphon and is discharged,
substantially as described.
2. The process of separating and treating oils and like liquids by subjecting them
to cold in the ascending leg of a siphon and thereby causing the impurities of greater
specific gravity to be deposited, substantially as described.
3. An apparatus for separating and treating oils and like liquids, substantially as
herein before described and shewn.
4. An apparatus for separating and treating oils and like liquids, consisting
essentially of a siphon the ascending heated leg of which is continued upwards to
such a height as will prevent the oil being drawn into the vacuum vessel or pump,
and in which the oil is fed into the lower end of the ascending leg of the siphon,
and passing upwards flows over into the descending leg which is continued to a lower
level than that at which the oil enters the ascending leg, substantially as shewn and
described.
5. In siphon apparatus for purifying and treating oils and like liquids, the
combination of an ascending leg, into which the oil is fed and heated, a descending
leg from which it flows out at a point below the level at which it enters, and a tube
extending above the same and connecting it to a vacuum vessel or pump, substan-
tially as shewn and described.
9,
6. In apparatus for purifying and treating oils and like liquids, the combination
of a chamber a, baving a steam jacket d, an oil supply pipe, an ascending tube
a moisture receiver with a vacuum pipe t, and an outflow pipe o, all arranged and
operating substantially as shewn and described.
7. An apparatus for purifying and treating oils and like liquids, constructed and
operating substantially as shewn and described with reference to Figs. 1 and 2.
Dated this 2nd day of Apri 1896.
GEO. MITCHELL.