An Improved Manufacture of Filtering Material.
Year: 1899

page_text: Date of Application, 19th June, 1899
Complete Specification Left, 19th Mar., 1900-Accepted, 21st Apr., 1900
PROVISIONAL SPECIFICATION.
An Improved Manufacture of Filtering Material.
I, GEORGE ALFRED ABBOTT, of 486, Collins Street, Melbourne, in the Colony
of Victoria, Australia, do hereby declare the nature of this invention to be as
follows:-
This invention has for object to provide an efficient and economical filter.
medium or material and one which when dirtied by use may be easily cleansed either
by washing or by heat, and it consists in the employment of a composition of
materials and the method or process by which the component parts are asso-
ciated together and afterwards treated in order to produce the filtering material.
According to my invention I take clay (either red or white in colour) exer-
cising special care that it is free from foreign matter, especially limestone, and
wash it with clean water into an impalpable condition so as to produce a pasty
result, free from lumps of any kind; this clay paste is then dried, until it
hardens, by exposure to the air or by evaporation in a heated appliance. The
dry result is then ground in any approved grinding appliance to an impalpable
powder resembling flour.
I next take a quantity of selected non-bituminous lignite and after drying
the same I grind it in any approved pulveriser into a powder which will pass
through a gauze of about 350 perforations to the square inch. It is absolutely
necessary that the lignite be non-bituminous and that it will not vitrify by
heat. I then mix 65 parts by bulk of the finely powdered clay with 35 parts
by bulk of the sifted non-bituminous lignite, thoroughly associate these materials
with one another in any approved mixing machine and add sufficient water
thereto to form a stiff paste. It is preferable that the mixing action should
be continued for some time after the water has been added to the parts before
described and until it may be fairly assumed that the non-bituminous lignite
has been equally disseminated throughout the clay. The stiff paste thus pro-
duced is then shaped on a potter's wheel into plates or blocks of the required.
shape and thickness to fit the filtering machine in which my material is to be
employed.
The plate or block, when removed from the potter's wheel, is partially dried
and placed under a press and a pressure of preferably about 4 tons per super-
ficial inch imposed upon it. The plate or block is then carefully, evenly and
slowly dried and then slowly heated in a potter's kiln and the temperature raised
until the plates are brought to a white heat. During the burning the fine par-
ticles of the non-bituminous lignite entirely disappear and leave small inter-"
stices in which an infinitesimal quantity of ash remains with no vitrifying
effect. I have found by experiment that the use of other than non-bituminous
lignite produces a vitreous remnant or coating which is impervious to the passage
of water, and therefore practically useless as a filter material.
. When the kiln has been allowed to cool down the plates will be found to be
of a uniform porosity and the minute interstices throughout the material will

page_text: be such as to allow a passage of water through the material but small enough
to prevent any bacilli, microbe, foreign or solid matter passing through. "I
find by practice that when my filtering material (manufactured as herein men-
tioned) is used a quantity of organic and solid matter deposited by the water
under filtration is left upon the outer side of the filter plate and that such
refuse may be freely removed by lixiviation by either hot or cold water or
the filter plate may be placed in any clean household fire and burnt to a red
heat so as to completely destroy any remnant of such matters. It will thus
be seen that the filtration properties of my material are indefinitely preserved.
The non-bituminous, non-vitrifying lignite may be obtained in the Colony
of Victoria, Australia.
Dated the 19th day of June 1899.
An Improved Manufacture of Filtering Material.
I, GEORGE ALFRED ABBOTT, of 486, Collins. Street, Melbourne, in the Colony
of Victoria, Australia, do hereby declare the nature of this invention and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention has for object to provide an efficient and economical filter
medium or material and one which when dirtied by use may be easily cleansed either
by washing or by heat, and it consists in the employment of a composition of
materials and the method or process by which the component parts are asso-
ciated together and afterwards treated in order to produce the filtering material.
According to my invention I take clay (either red or white in colour) exer-
cising special care that it is free from foreign matter, especially limestone, and
wash it with clean water into an impalpable condition so as to produce a pasty
result, free from lumps of any kind this clay paste is then dried, until it
hardens, by exposure to the air or by evaporation in a heated appliance. The
dry result is then ground in any approved grinding appliance to an impalpable
powder resembling flour.
I next take a quantity of selected non-bituminous lignite and after drying
the same I grind it in any approved pulveriser into a powder which will pass
through a gauze of about 350 perforations to the square inch. It is absolutely
necessary that the lignite be non-bituminous and that it will not vitrify by
heat. I then mix 65 parts by bulk of the finely powdered clay with 35 parts
by bulk of the sifted non-bituminous lignite, thoroughly associate these materials
with one another in any approved mixing machine and add sufficient water
thereto to form a stiff paste. It is preferable that the mixing action should
be continued for some time after the water has been added to the parts before
described and until it may be fairly assumed that the non-bituminous lignite
has been equally disseminated throughout the clay. The stiff paste thus pro-
duced is then shaped on a potter's wheel into plates or blocks of the required
shape and thickness to fit the filtering machine in which my material is to be
employed.
The plate or block, when removed from the potter's wheel, is partially dried
and placed under a press and a pressure of preferably about 4 tons per super-
ficial inch imposed upon it. The plate or block is then carefully, evenly and

page_text: slowly dried and then slowly heated in a potter's kiln and the temperature raised
until the plates are brought to a white heat. During the burning the fine par-
ticles of the non-bituminous lignite entirely disappear and leave small inter-
stices in which an infinitesimal quantity of ash remains with no vitrifying
effect. I have found by experiment that the use of other than non-bituminous
lignite produces a vitreous remnant or coating which is impervious to the passage
of water and therefore practically useless as a filter material.
When the kiln has been allowed to cool down the plates will be found to be
of a uniform porosity and the minute interstices throughout the material will
be such as to allow a passage of water through the material but small enough
to prevent any bacilli, microbe, foreign or solid matter passing through. I
find by practice that when my filtering material (manufactured as herein men-
tioned) is used a quantity of organic and solid matter deposited by the water
under filtration is left upon the outer side of the filter plate and that such
refuse may be freely removed by lixiviation by either hot or cold water or
the filter plate may be placed in any clean household fire and burnt to a red
heat so as to completely destroy any remnant of such matters. It will thus
be seen that the filtration properties of my material are indefinitely preserved.
The non-bituminous, non-vitrifying lignite may be obtained in the Colony
of Victoria, Australia.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1
1. A filtering material compounded from a mixture of pulverized clay with
pulverized non-bituminous, non-vitrifying lignite incorporated together and burnt,
substantially as described.
2. Filtering material compounded from a mixture of about 65 parts by bulk of
relay with 35 parts by bulk of non-vitrifying non-bituminous lignite, associated and
burnt together substantially as described.
3. A method or process of manufacturing a filtering material compounded of
non-vitrifying, non bituminous lignite with clay consisting of pulverizing the
materials associating them together in their proportions with water to form a
paste subjecting the result therefrom to pressure slowly drying the pasty material
then placing it in a kiln and slowly raising the temperature to a white-heat, sub-
stantially as described.
Dated this 19th day of March 1900.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.