IMPROVEMENTS IN APPARATUS FOR EFFECTING THE SEPARATION OF SOLID AND LIQUID BODIES
Year: 1882

page_text: PROVISIONAL SPECIFICATION left by Harry John Smith at the Office of
the Commissioners of Patents on the 8th March 1882.
HARRY JOHN SMITH Ph.D of Glasgow in the County of Lanark North
Britain "IMPROVEMENTS IN APPARATUS FOR EFFECTING THE SEPARATION OF
SOLID AND LIQUID BODIES
"
This Invention relates to improvements in the construction of machinery or
apparatus whereby solid bodies may be effectually separated from liquids in which
they are immersed or suspended, and liquids separated from liquids of different
specific gravity.
The improved machine or apparatus comprises a central vessel or strong framing
fixed upon a revolving shaft, and fitted with a number of close vessels disposed
radially round it, wherein the mixed solids and liquids are led to be separated by
centrifugal action, and from which the separated solids or heavier bodies are ejected
or thrown out by the same action, while the lighter liquids are also drawn off,
without stopping the machine. The separating vessels are by preference made
conical, or as frustra of cones, with the base of the cones flanged and securely bolted
to the central revolving vessel or framing. The base or inner end of each vessel is
fitted with a strong plate between the securing flanges of the vessels; and through
this plate the mixture of solids and liquids is led into the conical vessel by a pipe,
carried through or outside the rotating shaft, from a supply tank above. The apex
or outer end of each conical vessel is formed with a circular or other aperture or
opening into which a conical plug fits as a valve opening inwards, and with the
internal edge of the aperture forming a seat; the valve or seat being fitted if desired
with a ring of rubber or elastic yielding material. This plug or valve is fitted on a
central spindle which passes by a stuffing box through the base or inner plate, and
is connected by a bell crank or other lever to a rod or lever within or outside the
central revolving shaft, operated by levers or hydraulic power to draw in the plug
or press it on to its seat; or this spindle may be operated by a worm and screw, or
other similar devices to open and close the valve.
The mixture of solids and liquids led into the conical vessels is separated by
centrifugal action, the heavier solid particles forming layers towards the outer ends
or apices of the cones, and the outward flow of the material being prevented by the

page_text: closing of the valve or plug. While the heavy solids settle towards the outer sides
of the vessels the lighter liquids pass by a pipe or pipes fitted in outlet openings in
the base or inner shell or plate which lead without the machine. Over the outlet
openings perforated plates, covered with filter cloth or other filtering medium, are
fitted, and these plates extend by preference over the whole inner surface of this
plate, so that the liquids may filter through at any part of the plate and escape by
the outlets; and around the valve spindle filter plates may also be fitted to facilitate
the withdrawal of the liquids. The outlet pipes for the liquids may be led inwards
to any suitable vessel, but I prefer to lead the pipes outwards, so that the outlet
openings shall be at a radial distance from the centre of the machine equal to or
greater than that of the filter plates, and by a minor improvement I make the outlet
pipes movable, or fit them with valves whereby the position of the outlet in relation
to that of the filter plates may be varied or adjusted. By this means the liquid can
be drawn off continuously while the separation by centrifugal action takes place
within the vessels, and the filtration may be effected rapidly or slowly. In some
cases I also employ a head of the liquid and solid mixture or force the mixture into
the vessels by pumps to facilitate the separating and filtering operations. The
filtered liquid may also be drawn off by means of pumps or exhausters.
When the vessels are filled with the separated solid matter, the inlet of the mixture
is closed by a valve, the conical valve or plug within the conical vessel is drawn
inwards, and by the centrifugal action due to the continued rotation of the vessels,
the solid matter is ejected into any suitable receptacle without the machine. The
valve or plug is again closed against its seat, a fresh supply of the mixture admitted,
and the separating and filtering operations repeated. In some cases as for facilitating
chemical action or decomposition within the vessels, liquids or semi-liquids of different
chemical constitution may be led into the vessels by the same or separate inlets,
and stirring or agitating devices may be fitted within the vessels. Steam, or air,
or other gases may also be injected through the shells of the vessels.