AN IMPROVED METHOD OF WASHING OR REFINING CHINA CLAY, AND APPARATUS TO BE USED THEREIN
Year: 1880

page_text: LETTERS PATENT to John Lovering, the younger, of St. Austell, in the County
of Cornwall, China Clay Merchant, for an Invention of "AN IMPROVED
METHOD OF WASHING OR REFINING CHINA CLAY, AND APPARATUS TO BE
USED THEREIN."
PROVISIONAL SPECIFICATION left by the said John Lovering at the Office
of the Commissioners of Patents on the 10th December 1880.
JOHN LOVERING, the younger, of St. Austell, in the County of Cornwall, China
Clay Merchant. "AN IMPROVED METHOD OF WASHING OR REFINING CHINA
CLAY, AND APPARATUS TO BE USED THEREIN."
This Invention relates to improved method of and apparatus for washing or
refining china clays, whereby the operation is effected in a much better and more
efficient manner than hitherto.
It is well known that china clays in their crude state contain a quantity of sand,
grit, mica, and sometimes rooty and peaty matter. The pure clay is at present
extracted and freed from such foreign matters by washing the raw product in a
stream of water, which flowing through long channels, allows the sand and other
heavy particles to deposit themselves in the course. The lighter particles in
suspension, however, are not so easily disposed of, as they continue to float on in
suspension with the particles of clay, and it is usual to effect their separation by
stretching fine wire gauze or lawns made of silk, cotton, muslin, or other suitable
straining material in frames in fixed positions, and stationary in position across the
stream of water.
There is, however, a great difficulty in keeping the meshes of the gauze or lawn
clean, or clear from an accumulation of the matter, the progress of which they
arrest, though in some cases the frames are made to vibrate by being knocked with
a small hammer or stamp lifted by machinery.
The object of my Invention is to obviate this difficulty by rendering the gauze,
lawn, or straining frame self cleaning, which I effect by causing it to revolve or
otherwise keep in constant motion, whether it be caused to receive a backward and
forward or other motion in lieu of being stationary as at present.

page_text: My improved apparatus may be used in lieu of or in addition to the usual
apparatus to still further purify the clay.
A very advantageous way of carrying the principle of my Invention into effect
is to construct the straining frame as a cylinder having a wire, gauze, or lawn
circumference, the stream of water and clay entering at one end, the clay falling
through in solution, and passing on to the usual pits where it is precipitated, and
whence it can be removed for drying in the kilns, all foreign matter such as dirt,
leaves, and mica, which may be still in suspension, being retained within the
cylinder, and gradually finding its way in the revolution thereof to the opposite
end, the frame being a little inclined to facilitate this action, where they drop into
a suitable receptacle, and can be removed; and I render the gauze self-cleaning, by
causing a stream of water to fall over the top or side of the cylinder, so as to wash
away any adhering particles; or, by means of a current of air, a fresh and clean
surface being thus constantly presented to the stream of clay and water to be
purified.
In an equivalent arrangement a succession of straining frames may be successively
placed in the path of the stream of clay and water, one being removed as another
takes its place, each one being reversed after being used, so as to get rid of all the
impurities caught by it before being re-used.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Lovering in the Great Seal Patent Office on the 10th June
1881.
"AN
JOHN LOVERING, the younger, of St. Austell, in the County of Cornwall.
IMPROVED METHOD OF WASHING OR REFINING CHINA CLAY, AND APPARATUS
TO BE USED THEREIN.
"
This Invention relates to an improved method of and apparatus for washing or
refining china-clays, whereby that operation is effected in a much better and more
efficient manner than hitherto.
It is well known that china-clays in their crude state contain a quantity of sand,
grit, mica, and sometimes rooty and peaty matter. The pure clay is at present
extracted and freed from such foreign matters by washing the raw product in a
stream of water, which flowing through long channels allows the sand, mica, and
other comparatively heavy particles to deposit themselves in the course. The lighter
particles in suspension, however, are not so easily disposed of, as they continue to
float on in suspension with the particles of clay, and it is usual to effect their
separation by stretching fine wire gauze or lawns made of silk, cotton, muslin, or
other suitable straining material in frames in fixed positions, and stationary in
position across the stream of water.
There is, however, a great difficulty in keeping the meshes of the gauze or lawn
clean or clear from an accumulation of the matter, the progress of which they
arrest, though in some cases the frames are made to vibrate by being knocked with
a small hammer or stamp lifted by machinery.
The object of my Invention is to obviate this difficulty by rendering the gauze,
lawn, or straining-frame, self-cleaning, which I effect by causing it to revolve or
otherwise keep in constant motion, whether it be caused to receive a backward
and forward or other motion, in lieu of being stationary as at present, and by the
other means hereinafter mentioned.
I prefer to use my improved apparatus in combination with the ordinary methods
of refining or washing clays, to still further purify the clay, though in some cases
may be used in lieu thereof.
it
A very advantageous way of carrying the principle of my Invention into effect
is illustrated on the accompanying Sheet of explanatory Drawings in Figures 1, 2,
and 3, which respectively represent a side elevation, an end elevation, and a plan
view.
According to this modification the straining-frame is represented as constructed
as a cylindrical framing 1 having a circumference 2 formed of brass wire, or other
gauze or lawn, which is stretched within the framing 1 so as to avoid any inner
projecting parts.
The stream of water and clay is conducted from the hereinbefore mentioned long
channels, in which it deposits the heavier particles it carries in suspension by means
of a trough or channel 3 into within the cylinder 1, by which the process of
purifying it from the lighter particles is completed; and I find it of advantage to
line the entering end of the cylinder 1 with sheet zinc 4, so as to cause a spreading
out of the entering stream before it reaches the gauze or lawn circumference 2. As
it reaches this part the clay particles fall through in solution into a trough or
channel 5, by which the stream in its purified state is conducted to the usual pits
in which it is precipitated, and whence it can be removed for drying in the usual
kilns, and all the foreign matter (such as dirt, portions of leaves, and mica), which
was in suspension when the stream entered the cylinder, is retained within the
cylinder and gradually finds its way in the revolution thereof to the opposite end
(the cylinder frame being slightly inclined to facilitate this action), where they

page_text: drop into a trough or channel 6 and flow away, or into any suitable receptacle by
means of which they can be removed. The revolution of the cylinder is caused by
the aid of any suitable gearing 7, the shaft 8 being driven by a small water wheel,
or other convenient motive power.
I render the gauze or lawn self-cleaning by causing a stream of water to flow
over the edge of a channel or trough 9, and over or onto the top outer side of the
cylinder, so as in passing to within the cylinder to wash away any adhering
particles, or by directing a forcible current of air against the gauze or lawn, or by
other equivalent means, and I thus ensure a fresh and clean surface being constantly
presented to the stream of clay and water entering the cylinder to be purified.
The straining-frame need not necessarily be cylindrical, it may be made of an
octagonal shape, or of any other suitable shape with any convenient number of
sides.
Having now described the nature and object of my said Invention, together
with the manner in which the same is to be or may be performed or carried
into practical effect, I would remark in conclusion that what I believe to be novel
and original, and therefore claim as the improvements constituting the Invention
secured to me by the herein before in part recited Letters Patent is,-
The application and use, in combination with the ordinary methods of refining
or washing china-clays of the hereinbefore described improved apparatus, or of any
simple modification thereof, the purpose of utility of which is to still further purify
the clay than is effected by the ordinary methods of refining or washing it, and
the peculiarity of which apparatus is that in each modification of which it is
susceptible, it is caused to revolve or otherwise keep in constant motion, in lieu of
being stationary as straining frames are at present constructed, and that it is
rendered self-cleaning, substantially as and by the means hereinbefore referred to,
and illustrated on the accompanying Sheet of Drawings.
In witness whereof, I, the said John Lovering, have hereunto set my hand
and seal, this Sixth day of June, in the year of our Lord One thousand
eight hundred and eighty one.
JOHN LOVERING J". (L.S.)