Improvements in Separating Solid from Liquid Matter, more especially relating to the Treatment of Slimes, Finely Divided Ore, Precipitates, and Sewage.
Year: 1893

page_text: Date of Application. 6th Nov., 1893
Complete Specification Left, 7th Aug., 1894-Accepted, 6th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in Separating Solid from Liquid Matter, more
especially relating to the Treatment of Slimes, Finely Divided
Ore, Precipitates, and Sewage.
1, CHARLES RALEIGH, of Johannesburg, in the South African Republic,
Milling Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in separating solid from liquid matter,
and is more especially applicable for treating slimes or finely divided ore containing
precious metal according to the method described in the Provisional Specification
accompanying my application for Letters Patent No. 5163 of 1893, or for
accelerating the precipitation of chemicals or sewage.
In the method above referred to, the mass of slimes or finely divided ore is kept
in a state of vibratory or pulsatory movement by means of fluid pumped or forced
into and out of the vat or filter; the passage leading from the pump or pulsator
being under or over the filter-bed or at the side or bottom of the filter, vat or other
receptacle.
In the improved apparatus, the filter-bottom is divided into numerous sections;
one series, comprising alternate sections, being connected to one pipe and the other
series, comprising the remaining sections, to another pipe. The fluid is for a time
injected through one pipe and series of sections and ejected or exhausted through
the other pipes and series of sections, and then, by turning a four-way cock, the
action is reversed, the fluid being injected through the second pipe and series of
sections and ejected or exhausted through the first pipe and series of sections.
The reversal of the action may take place as frequently as found desirable.
It is usual in the process of precipitation to let the liquid containing the precipitate
remain at rest and allow the precipitate to gradually settle under the influence of
gravity; the clear liquid being then decanted or drawn off. In the case of a light
precipitate, several hours-and, in some cases, days-are required for the precipitate
to settle, and even then decantation, however carefully conducted, causes a loss.
By placing the liquid to be treated in a vat or receptacle furnished with a
filter-bottom, preferably divided into sections, and being in communication with an
exhaust pump or pulsator, precipitation is greatly facilitated.
For example, if it be required to precipitate gold from a solution of chloride of
gold, the solution is put into a vat of the kind described. The precipitant (say,
sulphate of iron) is then added; and, as the precipitate begins to form, the
exhaust pump or pulsator draws it through the liquid to the top of the filter.
The liquid withdrawn by the exhaust pump or pulsator is immediately returned to
the upper part of the vat.
In order to prevent the filter-bed becoming choked too rapidly by the precipitate,
the exhaust pump or pulsator may be caused to intermittingly inject air or liquid;
such treatment having the effect of reopening the closed passages.
Dated the 0th day of Autobox 1802
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Chartered Patent Agent.

page_text: COMPLETE SPECIFICATION.
Improvements in Separating Solid from Liquid Matter, more
especially relating to the Treatment of Slimes, Finely Divided
Ore, Precipitates, and Sewage.
I, CHARLES RALEIGH, of Johannesburg, in the South African Republic, Milling
Engineer, 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 improvements in separating solid from liquid matter,
and is more especially applicable for treating slimes or finely divided ore containing
precious metals according to the method described in the Specification to my
Letters Patent No. 5163 of 1893, or for accelerating the precipitation of chemicals
or sewage.
In the method above referred to, the mass of slimes or finely divided ore is kept
in a state of vibratory or pulsatory movement by means of fluid pumped or forced
into and out of the vat or filter; the passage leading from the pump or pulsator
being under or over the filter-bed or at the side or bottom of the filter, vat or other
receptacle.
In the improved apparatus, the filter-bottom is divided into numerous sections;
one series, comprising alternate sections, being connected to one pipe, and the other
series, comprising the remaining sections, to another pipe. The fluid is for a time
injected through one pipe and series of sections and ejected or exhausted through
the other pipe and series of sections, and then, by turning a four-way cock, the
action is reversed; the fluid being injected through the second pipe and series of
sections and ejected or exhausted through the first pipe and series of sections. The
reversal of the action may take place as frequently as found desirable.
It is usual in the process of precipitation to let the liquid containing the
precipitate remain at rest and allow the precipitate to gradually settle under the
influence of gravity, the clear liquid being then decanted or drawn off.
In the case
of a light precipitate, several hours-and, in some cases, days--are required for the
precipitate to settle, and even then decantation, however carefully conducted, causes
a loss.
By placing the liquid to be treated in a vat or receptacle furnished with a filter-
bottom, preferably divided into sections, and being in communication with an
exhaust pump or pulsator, precipitation is greatly facilitated.
For example, if it be required to precipitate gold from a solution of chloride of
gold, the solution is put into a vat of the kind described. The precipitant (say,
sulphate of iron) is then added; and, as the precipitate begins to form, the exhaust
pump or pulsator draws it through or with the liquid to the top of the filter. The
liquid withdrawn by the exhaust pump or pulsator is immediately returned to the
upper part of the vat.
In order to prevent the filter-bed becoming choked too rapidly by the precipitate,
the exhaust pump or pulsator may be caused to intermittingly inject air or liquid;
such treatment having the effect of reopening the closed passages.
The accompanying diagrammatic plan shows the filter-bed A divided into
alternate sections B and C. The sections B are connected to one pipe and the
sections C to another pipe. The sections B are used alternately with the sections C,
as previously explained.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, I claim :-
1. For use in separating solid from liquid matter, the improved apparatus
constructed or operating substantially as herein described.

page_text: 2. In apparatus for separating solid from liquid matter, dividing the filter bottom
into sections and grouping these sections into series in such manner that in
working the fluid is injected through one series and ejected or exhausted through
the other series of sections, the action being from time to time reversed, substan-
5tially as herein described.
3. In filtering solutions containing precipitates, the employment of a pump or
equivalent means which serves to draw the precipitate down to the top of the filter
and to return the filtered liquid to the upper part of the vat or other receptacle
containing the liquid under treatment, substantially as and for the purpose herein
set forth.
4. In filtering solutions containing precipitates, the employment of a pump or
equivalent means which serves to draw the precipitate down to the top of the filter,
and which is caused to intermittingly inject a fluid, substantially as and for the
purpose herein set forth.