IMPROVEMENTS IN MACHINERY OR APPARATUS FOR EFFECTING THE SEPARATION OF SOLID BODIES FROM EACH OTHER OR FROM LIQUIDS, AND OF LIQUIDS FROM LIQUIDS
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Harry John Smith at the Office of
the Commissioners of Patents on the 2nd July 1881.
HARRY JOHN SMITH, Ph.D. of Glasgow, in the County of Lanark, North
Britain. "IMPROVEMENTS IN MACHINERY OR APPARATUS FOR EFFECTING THE
SEPARATION OF SOLID BODIES FROM EACH OTHER OR FROM LIQUIDS, AND OF
LIQUIDS FROM LIQUIDS."
This Invention relates to certain improvements in the construction of machinery
or apparatus to be employed in effecting the separation of solid bodies from each
other or from liquids, and of liquids from liquids.
The improved machine is constructed so that two circular or other shaped
vessels provided with inlets and outlets, which may be protected by filtering
apparatus, rotate together about the same axis, and whose edges, flanged and so
arranged as to obtain close and perfect contact, are brought together or separated
during rotation by devices specially designed for this purpose.
to
In carrying out the Invention according to a modification adapted for the
separation of chemical precipitates from fluids, or of bodies or substances heavier
than water from water, or of heavy liquids from lighter liquids, the improved
machine which I employ comprises two vessels, by preference slightly domed or
saucer-like in shape fitted the one over the other, or with the upper vessel as a
cover for the lower, with a rubber or other washer between them if necessary,
form a close water-tight joint. The lower vessel is fitted on a vertical rotating
shaft passing up through it, and on which the upper vessel may move or slide.
The liquid or semi-liquid substance to be treated is led into these vessels through
inlet tubes from above or through the central shaft, and the heavier solid particles
or liquids are separated from the lighter liquids by centrifugal action, as hereinafter
more particularly described.
Within the space enclosed by the two vessels round the axis of rotation is a
cylindrical partition fixed and fitted close to the top vessel and having a closed top
and bottom. This partition may be perforated and covered with a filtering medium
and formed also with channels or with inner concentric perforated partitions
1

page_text: covered in the same manner if desired for the escape of the filtered liquid; or
instead of the partitions referred to, perforated discs covered with filtering cloth
may be fitted round the central shaft, or other outlets to intercept solid matter in
the outflowing liquids. Ports or openings with or without check valves are
constructed underneath the partition, protected or not, as found desirable, by
filtering media leading to a pipe or outlet which passes up through the bottom and
top of the cylindrical partition, and which is fitted with check valves. From the
sides of this pipe or outlet, other outlets are placed which lead to vessels without
the machine. The mixture of liquids and solids to be treated is led down to the
circular vessels from a supply tank, which consists of an open circular vessel whose
centre is preferably in the axis of rotation and which may have two or more pipes
in its bottom and fixed on each side of the axis of rotation. These pipes lead
firstly down along lines parallel or nearly parallel with the axis of rotation, and
then at angles to these lines through the partition (within the separating vessel)
and its sides or other convenient part.
When the machine is set in motion and a certain velocity is attained, the mixed
solids or liquids are delivered into the circular inlet vessel or supply tank, and
pass thence through the inlet pipes or central ducts into the space formed by the
circular separating vessels, and whose edges must now be in perfect contact. The
solids pass in due course of time to the point furthest from the centre of rotation,
forming annular layers, and the liquid passes through the parts or openings
underneath the bottom of the partition into the discharge pipe, and thence finally
into a vessel without the machine. As soon as the solids arrange themselves
around the sides of the partition or on the central discs, the delivery of mixed
solids and liquids is stopped, the flanged edges of the circular vessel are separated
preferably without stopping the machine, and through the opening thus formed the
solids, as mud or sludge, are thrown from the machine by reason of centrifugal
force. When the discharging is completed, the edges of the vessels are brought
into contact again and the procedure described is repeated.
One of the vessels, preferably the upper one or cover, is formed with a number of
wedges or inclined planes ranged circumferentially round the upper surface near
the rim or edge, and the other vessel is fitted with small brackets carrying pulleys
or friction rollers immediately over the wedges or inclined cam surfaces. These
pulleys or rollers are so arranged in relation to the inclines or wedges that the
rollers when over the wedges may bear on and press down the upper vessel or
cover into close contact with the lower vessel; and by being moved off the wedges
may allow the vessels to move apart on their axis or open out. The operation of
opening and closing the circular vessels may be performed automatically if desired,
in the first case by causing the one vessel fixed to the rotating shaft to be retarded
while the acquired momentum of the other makes it race or rotate past the first
during a part of the revolution, and thereby frees the wedges or inclines past the
bearing rollers to allow the vessels to open. While for the closing movement the
fixed vessel may be made to overtake the loosely revolving vessel or cover and
cause the rollers to mount on to the inclines or wedges to press the rims of the
vessels together. The extent of the motion of the rotating circular vessels over
each other may be limited by stops, and the extent to which the vessels may be
opened will be likewise limited and maintained in position by suitable devices.
The opening and closing of the vessels may be effected by hand by stopping the
machine, and in this case ordinary screw bolts may be used instead of the wedges
and rollers described.
The mixture of solids and liquids to be separated may generally with advantage
be forced into the circular containing vessels under pressure or otherwise; the
liquid matter may be pumped out through a filtering medium.
When solids are to be separated from solids of different specific gravity, the
machine is so modified as to collect the lighter bodies near the axis of rotation.
For instance, if a mass of cinders, ashes, and small unburned coal are to be treated,
the upper vessel or cover is made open above or formed with cross bars carrying

page_text: an outer lower rim which is formed with ports or openings to allow the lighter
substances to be thrown out; and instead of the cylindrical partition being closed
at the top and fixed to the top circular vessel, there is an open vessel with a
perforated bottom fixed round the axis of rotation, and also rotating, which vessel
can be raised to the ports in the rim and lowered at will during rotation.
The machine is filled with water or other fluid, the mass under treatment is
thrown into the machine, the lighter bodies, that is, the unburned or partially
burned coals, move towards the centre of rotation, and by raising the vessel with
the perforated bottom, are thrown by means of centrifugal force beyond the
machine. The edges of the vessel are then opened, and the cinders, and ashes, and
water are thrown likewise without the machine.