Year: 1895

page_text: Date of Application, 21st Jan., 1895
Complete Specification Left, 20th Nov., 1895-Accepted, 21st Dec., 1895
A communication from ALBERT HAACKE, Manufacturer, of Celle, Province of
Hanover, in the Empire of Germany.
1, ALFRED JULIUS BOULT of 323 High Holborn in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention to be as
follows:-
This invention relates to the filtering of liquids by means of pressure filters
containing blocks or cylinders of kieselguhr, porcelain, asbestos or other suitable
material, the effective cleaning of which has hitherto been a tedious and difficult
process, when the blocks or cylinders have become sooner or later choked with
impurities.
The present invention dispenses with this difficulty by first forming a coating
over the surface of the blocks over which coating the impurities gradually
deposit and after the layer of impurities becomes so thick as to interfere
with the free flow of the filtered liquid to reverse the pressure and to force some of
the filtered liquid back through the blocks, thus forcing off the whole coating
together with the accumulated impurities leaving the clean blocks exposed which
can then be coated again and the whole process repeated as before as long as it is
required.
In order to form the coating over the blocks or cylinders I place in the vessel
containing them a suitable quantity of material in a powdered form floating in some
of the liquid which is to be filtered and as I then force this liquid into and through
the filtering blocks the powdered material floating in it will remain evenly distributed
upon the outside of the filter blocks.
In order to clean the coating with the impurities off the blocks steam, air or
other pressure may be employed as desired, but when steam or hot air is used
the heat contained in it can at the same time be utilized to sterilize the filters.
Many different kinds of materials may be employed for the coating such for
instance as kieselguhr, porcelain, powdered charcoal, asbestos in the form of a fine
powder or fibre or other suitable material which will float in the liquid long enough
to be deposited evenly over the filtering surface when the liquid is forced through
the blocks or cylinders.
I prefer to connect a funnel or equivalent with the interior of the vessel by a tap
through which the powder etc. which is to form the protective coating may enter,
after having been placed in the funnel.
The advantages of this invention are
1, that by the application and the removal of this protective coating the
accumulated impurities can be quickly washed out of the filter without opening the
vessel and removing the blocks.
2, that the impurities are deposited much more loosely in and over the protective
coating and that therefore the layer of impurities is not so dense as if it were
deposited on the surface of the filtering block itself, the consequence being that the
filter blocks will filter considerably longer than if not thus coated.

page_text: 3, that the filter blocks or cylinders will last considerably longer as they are not
worn away by being rubbed or brushed frequently.
Dated this 21st day of January 1895.
BOULT & WADE,
Agents for the Applicant.
A communication from ALBERT HAACKE, Manufacturer, of Celle, Province of
Hanover, in the Empire of Germany.
I, ALFRED JULIUS BOULT, of 323 High Holborn, in the County of Middlesex,
Chartered Patent Agent, do hereby declare the nature of this invention, and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
This invention relates to the filtering of liquids by means of pressure filters
containing blocks or cylinders of kieselguhr, porcelain, asbestos or other suitable
material, the effective cleaning of which has hitherto been a tedious and difficult
process, when the blocks or cylinders have become sooner or later choked with
impurities.
The present invention dispenses with this difficulty by first forming a coating
over the surface of the blocks over which coating the impurities gradually deposit
and after the layer of impurities becomes so thick as to interfere with the free
flow of the filtered liquid reversing the direction of the pressure to force some of
the filtered liquid back through the blocks, thus forcing off the whole coating
together with the accumulated impurities leaving the clean blocks exposed which
can then be coated again and the whole process repeated as before as long as it is
required.
In order to form the coating over the blocks or cylinders I place in the vessel
containing them a suitable quantity of material in a powdered or fibrous form
floating in some of the liquid which is to be filtered and as I then force this liquid
into and through the filtering blocks the powdered material floating in it will
become evenly distributed upon the outside of the filter blocks.
In order to clean the coating with the impurities thereon off the blocks, steam,
air or other pressure may be employed as desired; when steam or hot air is
used the heat contained in it can at the same time be utilized to sterilize the filters.
Many different kinds of materials may be employed for the coating such for
instance as kieselgubr, porcelain, powdered charcoal, asbestos in the form of a fine
powder or fibre or other suitable material which will float in the liquid long enough
to be deposited evenly over the filtering surface when the liquid is forced through
the blocks or cylinders.
I prefer to connect a funnel or equivalent with the interior of the vessel by a tap
through which the powder etc. which is to form the protective coating may enter,
after having been placed in the funnel.
The advantages of this invention are
1, that by the application and the removal of this protective coating the
accumulated impurities can be quickly washed out of the filter without opening the
vessel and removing the blocks.
2, that the impurities are deposited loosely in and over the protective coating and
that therefore the layer of impurities is not so dense as if it were deposited on the
surface of the filtering block itself as in filters as ordinarily arranged, the
consequence being that the filter blocks will filter considerably longer than if not
thus coated,

page_text: 3, that the filter blocks or cylinders will last considerably longer than those
in other filters as they are not worn away by being rubbed or brushed so
frequently.
Having now particularly described and ascertained the nature of the said inven-
tion, as communicated to me by my foreign correspondent, and in what manner the
same is to be performed, I declare that what I claim is ;-
1. Removing a protective coating applied to a filtering medium together with
the impurities deposited thereon by fluid passed through the medium in a direction
opposite to that of the normal flow of the liquid through the filter.
2. The improvements in or relating to filtering operations consisting in forming
on the filtering medium a readily removable deposit or coating which intercepts
the impurities contained in the liquid being filtered and removing this coating
together with the impurities deposited thereon by fluid pressure passed through the
filtering medium in a direction opposite to that of the normal flow of liquid through
the filter thus cleansing the filtering surface effectually without opening the filter
casing.
www
FISTCHENOT 40300
A. HAACKE.
Boult & Wade,
Agents for the Applicant.
A. HAACKE.
Boult & Wade,
Agents for the Applicant.