IMPROVEMENTS IN FILTERING AND SEPARATING SOLIDS FROM LIQUID MATTERS, AND IN APPARATUS, TO BE EMPLOYED THEREFOR."
Year: 1881

page_text: LETTERS PATENT to Edwin Powley Alexander, of 14 and 36, Southampton
Buildings, in the County of Middlesex, Consulting Engineer, and British and
Foreign Patent Agent, for an Invention of "IMPROVEMENTS IN FILTERING
AND SEPARATING SOLIDS FROM LIQUID MATTERS, AND IN APPARATUS, TO BE
EMPLOYED THEREFOR." A communication from abroad by Paul Casamajor,
of Brooklyn, King's County, New York, and Charles Henry Senff, of the City,
County, and State of New York, in the United States of America.
PROVISIONAL SPECIFICATION left by the said Edwin Powley Alexander
at the Office of the Commissioners of Patents on the 3rd February 1881.
EDWIN POWLEY ALEXANDER, of 14 and 36, Southampton Buildings, in the
County of Middlesex, Consulting Engineer and British and Foreign Patent Agent.
"IMPROVEMENTS IN FILTERING AND SEPARATING SOLIDS FROM LIQUID MATTERS,
A communication from
AND IN APPARATUS TO BE EMPLOYED THEREFOR."
abroad by Paul Casamajor, of Brooklyn, King's County, New York, and Charles
Henry Senff, of the City, County, and State of New York, in the United States of
America.
This Invention relates to filtering or separating liquid from solid matter, and
consists of the method and apparatus hereinafter described, whereby the filtering
medium is maintained at all times in such a free and unobstructed condition that it
will work continuously with the desired rapidity and efficiency.
For
According to this Invention superposed sheets or layers of filtering material are
employed, and as the outer sheet or layer becomes obstructed or clogged the same
is removed, while the filtering is carried on by the remaining layers. Various
modes of construction may be adopted in carrying out this Invention.
example, the sheets of filtering material may be flat and superposed opposite an
opening, or at one side of a casing, into or out of which the liquid to be filtered is
directed in any suitable manner, the outer or inner sheets being successively
removed as they become clogged; or the filtering material may be in the form of
concentric hollow cylinders or successive coils, of which the outer or inner cylinders
or coils are successively removed as may be necessary; and other constructions will
DC71

page_text: occur to those skilled in the art. A preferable construction is a filtering material
in one continuous sheet on rolls.
It will be found advisable in many instances to pass the sheet between pressure
rolls, whereby any liquid in the deposit or dregs is squeezed out, thereby
preventing any loss of the same; in some cases a scraper may be used to remove
the dregs.
Instead of a cylinder the cloth may be wound round a frame, with square,
octagonal, or other base. Where the filtering material consists of separate sheets,
square or angular cases are substituted for cylinders, and the superposed sheets are
placed upon one or more sides of each case, which sides are open or perforated, and
any suitable means for successively removing and replacing the sheets automatically
or otherwise may be adopted.
In some cases two revolving perforated cylinders or casings may be used in
separate vats, the filter cloth being arranged to be wound from one cylinder or
casing to the other as the same are revolved, any convenient means being also
employed for forcing or exhausting the fluid to be filtered into one casing, and for
forcing or exhausting water or other cleansing liquid into the other casing.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Edwin Powley Alexander in the Great Seal Patent Office on the
29th July 1881.
EDWIN POWLEY ALEXANDER, of 14 and 36, Southampton Buildings, in the
County of Middlesex, Consulting Engineer and British and Foreign Patent Agent.
"IMPROVEMENTS IN FILTERING AND SEPARATING SOLIDS FROM LIQUID MATTERS,
AND IN APPARATUS TO BE EMPLOYED THEREFOR." A communication from abroad
by Paul Casamajor, of Brooklyn, King's County, New York, and Charles Henry
Senff, of the City, County, and State of New York, in the United States of
America.
The said Invention consists of a filter, in which the filtering medium is main-
tained at all times in such a free and unobstructed condition that it will work
continuously with the desired rapidity and efficiency.
As is well known most of the ordinary forms of filters will work rapidly and
well when first put in operation, but as the refuse matter collects upon the surfaces
or in the interstices of the filtering media the efficiency of the filter is reduced, and
finally it becomes inoperative, rendering it necessary to discard it or to temporarily
suspend operations while the filter is cleansed.
The object of this Invention is to avoid the delays, expense, and other above
recited objections incident to ordinary modes of construction, which object I effect
by using superposed sheets or layers of filtering material, and as the outer sheet or
layer becomes obstructed or clogged removing the same, while the filtering is carried
on by the remaining layers.
Various modes of construction may be adopted in carrying out this Invention.
For instance, the sheets of filtering material may be flat and superposed opposite
an opening, or at one side of a casing, into or out of which the liquid to be filtered
is directed in any suitable manner, the outer or inner sheets being successively
removed as they become clogged; or the filtering material may be in the form of
concentric hollow cylinders, or successive coils or layers, of which the outer or inner
cylinders, coils, or layers are successively removed as may be necessary. Other
constructions will occur to those skilled in the art, but I prefer to use a filtering
material in one continuous sheet in rolls, as hereinafter described and illustrated by
the Drawings annexed.
And in order that the said Invention may be fully understood I shall now proceed
more particularly to describe the same, and for that purpose shall refer to the
several Figures on the explanatory Sheet of Drawings hereunto annexed, the same
letters of reference indicating corresponding parts in both the Figures.
Figure 1 of the Drawings is a sectional elevation of a filter constructed in
accordance with this Invention, and Figure 2 is a plan view of the same.
In this case the single sheet of filtering material a of textile fabric, wire cloth, or
other suitable material is wound upon a perforated case or cylinder A, closed at the
ends, turning in a vat B containing the liquid material to be filtered, and provided
with a hollow trunnion e, which may be connected with an exhaust pump or other
appliance, whereby the liquid is caused to pass from the vat through the roll of
filtering material into the cylinder, and out of the latter to any suitable receptacle.
The sheet is gradually or intermittently unwound from the filtering cylinder, so
that as the outer surface of the filter becomes obstructed it is gradually removed,
exposing a fresh unobstructed filtering medium, and thereby maintaining the
efficiency of the filter.
The filtering cylinder may be arranged with its axis in.a vertical line. I prefer
however to place it horizontally, and to combine therewith either a second perforated

page_text: cylinder C having closed ends and a hollow trunnion, and turning in a tank D, or
a winding apparatus serving merely as a reel. The filtering cloth a is wound upon
this cylinder or reel as it is unwound from the cylinder A. In case a cylinder, as
shown at C, is used, water can be forced into the cylinder C, and outwardly through
the meshes of the cloth, or inwardly by suction or pressure, thereby cleansing the
latter after the cloth has passed from the cylinder A. The cloth after being thus
treated may be easily removed, and if necessary further treated to get rid of
remaining impurities.
It will be found advisable in many instances to pass the sheet between pressure
rolls E, E, whereby any liquid in the deposit or dregs is squeezed out, thereby
preventing any loss of the same. In some cases a scraper may be used to remove
the dregs.
By the construction shown and described the filtering operation is practically
continuous, and the filtering medium may be maintained in its most effective
condition.
Instead of a cylinder the cloth may be wound round a prism, with square,
octagonal, or other base. Where the filtering material consists of separate sheets,
square or angular cases are substituted for cylinders A and C, and the superposed
shects are placed upon one or more sides of each case, which sides are open or
perforated, and any suitable means for successively removing and replacing the 2
sheets automatically or otherwise may be adopted.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and
original, and therefore claim as the Invention secured to me by the hereinbefore 2
in part recited Letters Patent is,-
First. The application and use to and in the filtering and separating of solids
from liquid matters of a filter provided with a series of removeable superposed
sheets, coils, or layers of filtering material, arranged substantially as described, to
permit the outer filtering surface to be renewed by the removal of the outer layers,
as set forth.
Secondly. The combination in a filter of a case or receptacle for the filtered
liquid, and superposed layers of filtering material arranged opposite the entrance to
said receptacle, and successively removeable, substantially as set forth.
Thirdly. The combination in a filter of a perforated case or cylinder commu-
nicating with an outlet for the filtering liquid, and a sheet of filtering material
wound in layers upon the said case, and removeable therefrom, substantially as set
forth.
Fourthly. The combination in a filter of the revolving perforated casings in
separate vats, and filter-cloth arranged to be wound from one casing to the other
as the same are revolved, and means for forcing or exhausting the fluid to be filtered
into one casing, and for forcing or exhausting water into the other casing, substan-
tially as set forth.
In witness whereof, I, the said Edwin Powley Alexander, have hereunto set
my hand and seal, this Twenty eighth day of July, in the year of our Lord
One thousand eight hundred and eighty one
]
EDWIN P. ALEXANDER. (L.S.).