IMPROVEMENTS IN THE PURIFICATION AND DECOLORIZATION OF DYE WATERS AND WATERS WHICH HAVE BEEN EXPLOYED IN WASHING LEAD MINERALS
Year: 1875

page_text: LETTERS PATENT to Charlton James Wollaston, of No. 65, West-
bourne Park Road, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN THE PURIFICATION AND DECOLORIZATION OF DYE
WATERS AND WATERS WHICH HAVE BEEN EXPLOYED IN WASHING LEAD
MINERALS."
Sealed the 11th January 1876, and dated the 13th July 1875.
PROVISIONAL SPECIFICATION left by the said Charlton James
Wollaston at the Office of the Commissioners of Patents, with
his Petition, on the 18th July 1875.
I, CHARLTON JAMES WOLLASTON, of No. 65, Westbourne Park Road,
in the County of Middlesex, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE PURIFICATION AND DECOLORIZATION OF
DYE WATERS AND WATERS WHICH HAVE BEEN EXPLOYED IN WASHING LEAD
MINERALS," to be as follows:-
This Invention has for its object improvements in the purification and
decolorization of dye waters and waters which have been employed in

page_text: washing lead minerals. I filter these impure waters through a filter,
in which the filtering medium is the coke or charcoal obtained from the
substance called blackstone or Kimmeridge shale in the process of its
destructive distillation in the manufacture of illuminating gas. This
coke or charcoal I have discovered has an extraordinary power in
absorbing impurities of these waters, and after filtration through such
a filter these noxious waters will be found to have become practically
pure, so that they may be discharged into any running stream without
nuisance or injurious consequences of any kind.
I also use the coke of boghead coal, Torbane Hill mineral, and Cannel
coal for the like purposes.
I have found that intermitting downward filtration' is the most
effectual, and I so arrange my filters that by means of an automatic or
self-acting arrangement one filter or set of filters is allowed to be out
of use and to aërate whilst the other or others are in action.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Charlton James Wollaston in the Great Seal Patent
Office on the 13th January 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLTON
JAMES WOLLASTON, of No. 65, Westbourne Park Road, in the County
of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of July, in the year
of our Lord One thousand eight hundred and seventy-five, in the thirty-
ninth year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Charlton James Wollaston, Her
special license, that I, the said Charlton James Wollaston, my exe-
cutors, administrators, and assigns, or such others as I, the said
Charlton James Wollaston, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United
Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for " IMPROVEMENTS IN THE PURIFICATION AND DECOLORISA

page_text: TION OF DIE WATERS AND WATERS WHICH HAVE BEEN EMPLOYED IN WASHING
LEAD MINERALS," upon the condition (amongst others) that I, the said
Charlton James Wollaston, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
3 seals, should particularly describe and ascertain the nature of the said
Invention, and in what manner the same was to be performed, and
cause the same to be filed in the Great Seal Patent Office within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Oharlton James Wollaston, do
hereby declare the nature of the said Invention, and in what manner
the same is to bo performed, to be particularly described and
ascertained in and by the following statement thereof, that is to
say:―
This Invention has for its object improvements in the purification and
decolorization of dye waters and waters which have been employed in
washing lead and other minerals. I filter these impure waters through
a filter, in which the filtering medium is the coke carbon or char
obtained from the substance called blackstone or Kimmeridge shale in the
process of its destructive distillation in the manufacture of illuminating
gas, or by specially coking the mineral in suitable retorts or coking ovens,
as is well understood. This coke carbon or char I have discovered has
an extraordinary power in absorbing impurities of these waters and in
the removal of coloring matters, and after filtration these noxious waters
will be found to have become practically pure, so that they may be
discharged into any running stream without nuisance or injurious con-
sequences of any kind.
Although in my Provisional Specification I mention the coke of bog-
head coal, Torbane Hill mineral, and Oannel coal for the like purposes,
I have since ascertained that the power of these cokes or charcoal is so
feeble as to render them of little practical value.
I have found. that intermittent downward filtration is the most
effectual, and I prefer to arrange my filters, two or more in number,
that whilst one filter is in use the other or others are allowed to be out
of action and to aerate; and I place these filters in such position as
to receive the refuse dyes direct from the vats; and the waters employed
in washing the newly dyed material I prefer to convey by suitable
channels in their most polluted condition direct to the filter.

page_text: For the purification of refuse waters from mines I find the carbon or
char to possess the property of arresting not only the matters held in
suspension, but also by a chemical action of absorbing, removing, or
neutralizing the mineral salts held in solution, especially those of
lead.
. From the washing floors the waters employed in washing the mineral
ores I convey by suitable troughs or channels to a series of filter beds;
the first into which the water is allowed to pass I construct of the
carbon or char in a coarse state of granulation, so as to intercept the
solid matters held in suspension, subsequently passing this partially
purified water to a filter of finer grained carbon, and so effectually
remove the whole of the suspended impurities, and so great a portion of
the soluble salts as to render the waters perfectly innoxious.
In the treatment of refuse dye waters I prefer that the filters be con-
structed only of sufficient area to suffice for the filtration of the quantity
required in each particular establishment or locality, as I find it better
to operate upon the refuse dyes as it is discharged from the vat without
much addition of water, and that the decolorization is more readily
effected if the refuse waters are subjected to filtration at a higher tem-
perature than the atmosphere.
For the filtration of 300 to 350 gallons of refuse dye per hour a
surface of about 36 superficial feet I find to be fully sufficient; and I
make my filtering apparatus for such a quantity by constructing a
strong tank 6 feet by 6 feet, and 6 feet deep; this tank I place very
slightly inclined from the front to the back in order to allow of the
escape of air by suitable escape pipes, which are provided. At the
bottom of this tank I provide perforated tiles, such as are used in malt kiln
floors, and upon these tiles I place a layer of carbon about three inches
in thickness, broken and sifted through a sieve of 3 to the inch, carefully
pressing the carbon slightly in order to obtain an uniform bed of filtering
material. I then proceed to add a second thickness of the carbon sifted
to a finer grain by a sieve about 4 or 5 to the inch. I build up the
filter bed with layers of this description, and of still finer carbon, each
of 3 or 4 inches thick, until I have a total depth of about 3 feet of
carbon; a top layer of 1 or 2 inches I place of coarser material, leaving
nearly 8 feet of depth for the refuse dye water.
I regulate the flow of the waters upon the surface of the filter either
by a perforated pipe or other readily understood contrivance, so as to

page_text: avoid a rush of water upon any one portion of the surface and allow of
the outflow from the bottom of the tank by means of a tap or valve.
I find it to be of great advantage to provide a means of admitting
steam into the lower part of the tank at times when it is not in use for
filtration, as the action of the steam revivifies the carbon to a con-
siderable extent.
As there is generally but little impurity held in suspension in refuse
dye waters the use of a rough filter, first, to remove the suspended
impurities is not generally, necessary, but in the treatment of waters
from the washing of minerals I prefer, first, to allow such waters to
pass through a depositing tank, and subsequently through a filter con-
structed with the coarser carbon, 3 or 4 to the inch, before admitting
the impure waters to the filter bed of finer carbon, which removes all
traces of suspended matter and arrests or absorbs the salts held in
solution.
For the filtration of large bodies of water which are only slightly
discolored or rendered impure filter beds constructed alternately with
layers of carbon and gravel will be found sufficient, allowing about 20
gallons to pass through each superficial foot per hour.
Having now described the nature of my said Invention and the
manner of performing the same, I would have it understood that I claim
as my Invention,-.
First. The purification of refuse dye waters by filtration through the
carbon, or char, or coke obtained from the mineral known as blackstone
or Kimmeridge shale, substantially as described..
Second. The purification of waters from the washing of lead minerals
by filtration through the carbon or char of 'blackstone or Kimmeridge
shale, substantially as described.
'In witness whereof. I. the said Charlton James Wollaston, have