Improvements in Apparatus for Electrolytical Purposes.
Year: 1894

page_text: Date of Application, 21st Apr., 1894
Complete Specification Left, 21st Jan., 1895-Accepted, 20th Apr., 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Electrolytical Purposes.
I, HERBERT GUTHRIE, of Albert Road, Levenshulme, near Manchester, in
the County of Lancaster, Civil Engineer, do hereby declare the nature of this
invention to be as follows:-
This invention of improvements in apparatus for electrolytical purposes has
reference more particularly to the diaphragms used in such apparatus, and it has for
object to obviate choking of the diaphragms and to prevent or lessen other
obstructions or resistances to the electric current and electrolytic action, such as are
usually to be found in electrolytical apparatus.
For this purpose I construct the diaphragms proper of some loose granular
substance that may be either soluble or insoluble such as salt or sand respectively,
as may best suit the particular operation in hand, and which is held in position by
screens of insoluble material. These screens on their inner sides, or those next the
granular material are so formed as to tend to prevent the said granular material
from dispersing either while being placed in position, or during the process of
electrolysis and descent by gravitation. For this purpose the said inner side of each
screen may be formed with an incline or series of inclines of such a slope as will
ensure that the said granular substance shall not reach the top or outer edge and
fall over, or when a broad horizontal shelf is preferred to a continuous incline the
breadth of the shelf may be such as will ensure the same object.
The form of the outer side of each screen, or that opposite an electrode, is such
as will ensure that the rising gases will pass up the face of the screen without
passing into or through the diaphragm. For this purpose the form of the outer
side of the screen or support is made the reverse of that of the inner side, the
combination producing a form practically corresponding to a series of louvres that
slope downwards to the granular diaphragm and upwards to the electrolyte and
rising gases. The said louvres may have a small lip at the bottom and be arranged
either in pairs or alternate. In the latter case the granular substance would take
a zig-zag course on its descent. The screens or supports are not necessarily made
of louvre shaped laths but may be of any convenient form that will serve the same
purpose, the spaces between the louvres being of any form superficially, even to
round holes. The screens may be made of any number of parts of simple
construction adapted to lie one in another and fit together in such a manner
that they will hold each other in proper position in conjunction with suitable
guides.
A granular depolariser may be used for the diaphragm, or for that part thereof
where the gases are formed. Or the depolariser may be in the form of a fine
In
powder suspended in the electrolyte, or fed into the apparatus from the top.
certain cases, the granular diaphragm may be formed of any one, two or three
of the following substances, viz. :-an insoluble, a soluble, or depolarising
substance.
a
In order to secure a compact diaphragmn when the saine is made of a soluble
granular substance, provision is or may be made to slightly agitate the granular
substance so as to prevent any bridging over of the particles thereof and the
formation of cavities. For this purpose movable arms may be arranged within
the diaphragms, or the screens, or one of them, or parts thereof may be made
D

page_text: movable to a small extent, or means may be provided for vibrating the screens or
the whole apparatus by rapping, the motion in either case being produced by any
suitable device operated either electrically or mechanically.
When using a soluble substance in conjunction with a depolariser, and, it may
be, with an insoluble substance as well, to form a diaphragm, the depolariser may
be such as to cause the formation of free water which, being in close proximity to
the soluble substance, forms a solution which is utilised to maintain the strength of
the electrolyte, the solution of part of the diaphragm causing movement of the
remaining part. Or, to ensure the movement of the substances of which the
diaphragm is formed, with the object of keeping the interstices between them open
and free, an electrolyte that is not fully saturated may be used so that the soluble
parts of the diaphragm will be dissolved and thereby so alter the structure of the
diaphragm that the insoluble parts thereof will fall together in fresh order.
make still further provision for movement and renewal of the diaphragm by
forming a cavity or exit opening beneath it in such a way as to admit of any desired
quantity of the granular material being allowed to drop out or lower its position.
This may be effected in various ways as for example by means of a series of
perforations controlled by a slide or slides, or by a screw or cavity conveyor. Or
there may be provided under the diaphragm a false bottom adapted to be lowered
at will. Or the false bottom may be fixed and the other part of the apparatus
raised. Or the whole apparatus may be placed in a tray or tank and the diaphragm
have no other bottom so that the component parts thereof will fall through at any
desired rate onto the tray when the apparatus is raised. The feed of the
electrolyte may be effected upwards or downwards through the granular substance,
by which means the tendency to accumulate dirt on the surface will be directly
counteracted.
A further modification of a renewable diaphragm according to this invention is
made by so proportioning the relative positions of the inner bottom edge of one
louvre and the outer top edge of the one below as to admit of an overflow of the
granular substance of the diaphragm when the same is agitated and in this way
secure a renewal of the outer surface of the diaphragm. This overflow may be
arranged to take place either from an upper louvre to one below or from all the
louvres to the bottom. In this case a cavity or exit opening is provided for the
said overflow immediately below the outside of the louvre sereens, viz.-between
the screens and the electrodes, the bottom of the diaphragm proper being closed. The
said cavities or exit openings may be made either entirely independent of each
other or be connected. In the latter case there is or may be a midfeather attached
to the solid bottom of the diaphragm of a depth sufficient to secure insulation by
dipping into the granular substance of the overflow. Sometimes I entirely close
the top of the diaphragm and leave open the bottom through which the granular
substance to form the diaphragm is pumped or forced so as to cause an overflow
through the louvres.
In order to secure as much breaking up of the diaphragm as possible, I sometimes
introduce interrupters between the louvres.
In another arrangement the louvres are entirely dispensed with, the granular
diaphragm being formed in a well arranged between the electrodes and into which
dips a midfeather to prevent direct electrolysis between the electrodes. Similar
means for disturbing and extracting or charging the granular substance is
provided as in the former cases; or feed holes may be made in the top of the
chamber; or a double midfeather may be provided open at the top to permit of the
introduction of fresh material to renew the diaphragm.
To counteract the injurious effect caused by the accumulation of minute globules
of gases and of deleterious deposit on the electrode or electrodes I provide one or
more brushes or squegees that may be operated from the moving parts of the
diaphragm screens or disturbing frames, or by a separate framework or device.
Where the electrodes are made double acting, the said brushes or squegees may be
made of a bridge or saddle form, that is to say, the brushes or squegees may have

page_text: arms extending down each side or face of the electrode and ride or slide along the
top edge.
In cases where the electrodes are single acting, that is, active on one face only 1
sometimes arrange them in louvre fashion so that the gases rising from the face of
a lower louvre may pass behind the louvre above.
By my invention electrolytic processes can be carried on in an efficient and
continuous manner.
Improvements in Apparatus for Electrolytical Purposes.
1, HERBERT GUTHRIE, of Albert Road, Levenshulme, near Manchester, in the
County of Lancaster, Civil 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 of improvements in apparatus for electrolytical purposes, has
reference more particularly to the diaphragms used in such apparatus, and it has
for object to obviate choking of the diaphragms and to prevent or lessen other
obstructions or resistances to the electric current and electrolytic action, such as are
usually to be found in electrolytical apparatus.
For this purpose I make be diaphragms proper as thin as possible consistent
with the object in view and of some loose granular substance, which may be either
soluble or insoluble, for instance salt or sand respectively, as may best suit the
particular operation in hand. I also provide for the continuous or intermittent
movement of the said granular substance in order to keep the interstices free and open,
as well as to admit of a renewal of the substance itself and so enable an indefinitely
continuous process of electrolysis being carried on.
The loose granular diaphragm substance is held in position by screens of insoluble
material. These screens ou their inner sides, or those next the granular material,
are so formed as to tend to prevent the said granular material from dispersing
either while being placed in position, or while descending by gravitation during the
process of electrolysis. For this purpose the inner side of each screen is by
preference formed with an incline or series of inclines of such a slope as will ensure
ihat the said granular substance shall not reach the top or outer edge and fall over,
or, when a broad horizontal shelf is preferred to a continuous incline, the breadth
of the shelf may be such as will ensure the same object. The form of the outer side
of each screen, or that opposite an electrode, is such as will ensure that the rising
gases will pass up the face of the screen without passing into or through the
diaphragm. For this purpose the form of the outer side of the screen or support is
preferably made the reverse of that of the inner side, the combination producing a
form practically corresponding to a series of louvres that slope downwards to the
granular diaphragm and upwards to the electrolyte and rising gases.
Fig. 1 of the accompanying illustrative drawings shows in longitudinal section
part of one form of electrolytical apparatus according to this invention, and
1 is
Fig. 2 shows a cross section thereof through one of the diaphragms thereof.
a frame in which are mounted louvres 2 constituting the screens between which the
granular substance forming the diaphragm 3 is retained. The louvres 2 are, as
shown in Fig. 2, arranged alternately, i.e. so as to overlap one another, thus causing

page_text: the granular substance to take a zig-zag course in its descent. They may, however
be arranged in pairs the two members of which are horizontally opposite each other as
shown in cross section in Fig. 3, so that the granular substance may pursue a straight
vertical course in its descent. In either case, the louvres may have a small lip 2,
at their upper or lower edges, as shown in Fig. 3, in order to prevent the sand
running over the outer edges of the louvres when descending quickly. Higher
pitched louvres serve the same end. 4 is a charging passage formed between two
parallel plates. 4 and constituting a feeding inlet and reservoir for the granular
material intended to form the diaphragm. The screens or supports are not
necessarily made of louvre shaped laths as shown, but may be of any other
convenient form that will serve the same purpose, the spaces between the louvres
being of any form superficially, even to round holes, as shown in vertical section in
Fig. 3. The screens may be made of any number of parts of simple construction
adapted to lie one in another and fit together in such a manner that they will hold
each other in proper position in conjunction with suitable guides in the frame 1.
Fig. 3 shows an arrangement in which each screen consists of a single inclined
plate 2, the two plates being inclined towards each other in a downward direction
and arranged below the charging passage 4 and above an exit passage such as
hereinafter referred to.
Fig. 3 shows an arrangement in which the inclined plates or louvres are replaced
by horizontal shelves 2* arranged at short distances apart and perforated so that the
granular material may pass through them from the charging passage to the exit
passage. The outer edges of the shelves may be formed with lips 2, as shown at
the left hand side of the figure, for the purpose herein before mentioned with
reference to Fig. 3.
In order to secure a compact diaphragm when the same is made of a soluble
or partly soluble granular substance, provision is made to slightly agitate the
granular substance so as to prevent any bridging over of the particles thereof and
the formation of cavities. For this purpose movable arms or parts may be
arranged within the diaphragms.
Fig. 4 shows in section an arrangement in which an agitator in the form of a
corrugated arm or strip 5 is arranged to be moved longitudinally between each
pair of screens, and Fig. 5 shows in section a modification in which a number of
arms 5 are moved longitudinally between consecutive louvres. Or the screens, or one
of them, or parts thereof, may be made movable to a small extent, as for example by
dividing the louvre frames down the centre and causing one half to slightly rise and
fall by means of suitable arms connecting arms operated by a crank motion. Or
the two halves may be slightly parted and brought together again by similar means.
Or the whole diaphragm inay be suddenly moved towards one electrode causing a
momentary pressure on one side and a vacuum on the other side and so cause the
whole substance of the diaphragm to move and perhaps overflow on one side, and
by a reverse movement to overflow on the other side. Or means may be provided
for vibrating the screens, or the whole apparatus by causing the latter to ride on
ratchet wheels and so produce jogging or rapping, the motion in either case being
produced by any suitable device operated either electrically or mechanically.
When using a soluble substance for example common salt, in conjunction with a
depolariser, and, it may be, with an insoluble substance as well such as sand, to
form a diaphragm, the depolariser may be such, for example peroxide of manganese,
as will cause the formation of free water, which, being in close proximity to the
soluble substance, will form a solution which is utilized to maintain the strength of
the electrolyte, the solution of part of the diaphragm causing movement of the
remaining part. Or, to ensure the movement of the substances of which the
diaphragm is formed, with the object of keeping the interstices between them open
and free, an electrolyte that is not fully saturated may be used, so that the soluble
parts of the diaphragm will be dissolved and the structure of the diaphragın
thereby so altered that the insoluble parts thereof will fall together in fresh order;
as this method tends to produce a saturated electrolyte, fresh weak electrolyte

page_text: should be supplied, either constantly or intermittently, as the converted liquor is
drawn off.
I make still further provision for movement and renewal of the diaphragm by
forming a cavity or exit opening beneath it in such a way as to admit of any
desired quantity of the granular material being allowed to drop out or lower its
position. This may be effected in various ways as, for example, by means of a
series of perforations or holes controlled by a slide or slides, or by a conveyor.
Figs. 1 and 2 show an arrangement in which holes are made in the frame 1
beneath the diaphragm 3 and are controlled by a conveyor 8 which is adapted to
slide in the bottoin of the frame 1 and is provided with cavities 9 which, when
moved from under the perforations 7, carry away definite quantities of the
granular diaphragm and allow them to drop through a series of holes 10 in the
bottom of the frame 1. Figs. 6 and 7 show a longitudinal section and a cross
section respectively of another arrangement in which an endless travelling band
conveyor 11 travelling over the inclined bottom of a groove 12 formed below the
hole in the frame 1, is employed for gradually carrying away the granular
substance of the diaphragm 3 from the hole 7.
Or there may be provided under the diaphragm as shown in section in Fig. 8,
a false bottom 12 adapted to be lowered, or moved horizontally, or both, at will;
or the false bottom may be fixed and the other part of the apparatus moved.
Or the whole apparatus may be placed in a tray or tank and the diaphragm
have no other bottom so that the component parts thereof will fall through at
any desired rate on to the tray when the frame carrying the diaphragm is raised.
Fig. 9 shows in vertical section another device for removing the granular
substance from the holes 7, or from a longitudinal slot formed in the frame 1 below
the diaphragm. In this case a roller 13 is employed which rotates in the direction
indicated by the arrow, a space 14 being left between the roller 13 and the
corresponding side of the frame to allow the granular substance to be carried
away by the said roller. The roller may be either grooved, or ungrooved as shown;
and in some cases may be made to oscillate about its axis, a space 14 being then
left at each side of the frame 1.
The granular substance may also be removed by forcing it, by suction or other
suitable means, through passages which communicate with the bottom of the
diaphragm. Figs. 10 and 11 are part vertical sections showing two arrangements
for this purpose.
In Fig. 10 the exit opening 7 at the bottom of the diaphragm
are connected to pipes 78 in connection with an exhauster such as a pump whereby
the granular substance is drawn off by suction. In Fig. 11 each opening 7 is
provided with a nozzle 7 furnished with an ejector 7° in communication with a
main pipe 7 containing fluid for example air, under pressure, whereby the said
material can be ejected from the nozzle 7.
A further modification of a renewable diaphragm according to this invention is
made by so proportioning the relative positions of the inner bottom edge of one
louvre 2 and the outer top edge of the one below, as to admit of an overflow of
the granular substance of the diaphragm when the same is agitated as before
described, and thereby to secure a renewal of the outer surface of the diaphragm.
Such an arrangement is shown diagrammatically in Fig. 12; Fig. 13 is a diagram
showing an arrangement for the same purpose in which the lower edges of the
louvres on one side are turned upwards under those of the other side; and Fig. 14 is
a diagram showing the adaptation to this purpose of the arrangement of the
louvres in pairs, a trough-like louvre 2 being arranged below each pair in such a
way as to deflect the granular substance outwards. In all these cases a cavity or
exit opening is provided for the said overflow immediately below the outside of the
louvre-screens, viz. between the screens and the electrodes, the bottom of the
diaphragm proper being closed. The said cavities or exit openings, may be made
either entirely independent of each other or be connected in the latter case there
may be attached to the bottom of the frame 1 a midfeather of a depth sufficient
to secure insulation by dipping into the granular substance of the overflow.

page_text: In another arrangement shown in section in Fig. 15, the louvres are entirely
dispensed with, the granular diaphragm being formed in a well 2 which is arranged
between the electrodes and into which dips a midfeather 4 which may be either
double, as shown, or single and formed of impervious material, to prevent direct
electrolysis between the electrode. The space between the two walls of the
midfeather serves as a charging hopper. Similar means for disturbing and
extracting the granular substance is provided in this arrangement as in the former
arrangements.
To counteract the injurious effect caused by the accumulation of minute globules
of gases and of deleterious deposit on the electrode or electrodes 15 (Figs. 4 and 5),
I provide one or more brushes or squegees 16 arranged to rub the surface of each
electrode and which may be operated from any suitable device as for example from
the moving parts of the diaphragm-screens or from the disturbing arms 5, by
arms 5 as shown in Fig. 4. Where the electrodes are made double-acting, the
said brushes or squegees 16 may be made of a bridge or saddle form, as shown in
Fig. 5, that is to say, the brushes or squegees may extend down each side or face
of the electrode and ride or slide along its top edge. When brushes or squegees
are used, the disturbing arms 5 for agitating the granular diaphragm 3 may be
carried and operated by them as shown in Fig. 5. The arms 5 or other agitators
employed as well as the backing of the brushes or squegees, should be perforated
or otherwise so constructed as not to materially interfere with the proper passage of
the electric current between the electrodes.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. In electrolytical apparatus, the combination of a diaphragm formed of loose
granular material and means whereby the said diaphragm can be moved or agitated
for the purpose of keeping open its interstices and preventing formation of cavities
substantially as herein described.
2. In electrolytical apparatus, a diaphragm composed of a combination of a
soluble, an insoluble and a depolarising substance, or of any two of them,
substantially as set forth.
3. In electrolytical apparatus, the combination of a diaphragm composed of
loose granular material and means for extracting the said material, substantially as
herein described for the purposes specified.
4. In clectrolytical apparatus, the combination with the electrodes, of movable
rubbing devices such as brushes or squegees adapted to clean the surfaces of the
electrodes, substantially as set forth."
5. In electrolytical apparatus, a holder or support for a diaphragm composed of
granular material, and means for agitating or removing the said granular material,
substantially as hereinbefore described with reference to the several examples
illustrated in the drawings annexed.
Dated this 21st day of January 1895.