IMPROVEMENTS IN THE TREATMENT OR PERIFICATION OF SEWAGE AND OTHER MATTERS, AND IN THE PREPARATION OF AGENTS TO BE USED IN SUCH TREATMENT, SOME OF WHICH ARE ALSO APPLICABLE TO OTHER PURPOSES
Year: 1876

page_text: LETTERS PATENT to Christopher Rawson, of No. 9, Victoria Chambers, in the
City of Westminster, Managing Director of the Native Quano Company
(Limited), and John William Slater, of No. 2, Tamworth Terrace, in the
County of Middlesex, Analytical Chemist, for the Invention of "IMPROVEMENTS
IN THE TREATMENT OR PERIFICATION OF SEWAGE AND OTHER MATTERS, AND IN
THE PREPARATION OF AGENTS TO BE USED IN SUCH TREATMENT, SOME OF WHICH
ARE ALSO APPLICABLE TO OTHER PURPOSES."
Sealed the 21st October 1876, and dated the 5th May 1876.
PROVISIONAL SPECIFICATION left by the said Christopher Rawson and John
William Slater at the Office of the Commissioners of Patents on the 5th May
1876.
CHRISTOPHER RAWSON, of No. 9, Victoria Chambers, in the City of Westminster,
Managing Director of the Native Guano Company (Limited), and JOHN WILLIAM
SLATER, of No. 2, Tamworth Terrace, in the County of Middlesex, Analytical
Chemist. "IMPROVEMENTS IN THE TREATMENT OR PURIFICATION OF SEWAGE AND
OTHER MATTERS, AND IN THE PREPARATION OF AGENTS TO BE USED IN SUCH
TREATMENT, SOME OF WHICH ARE ALSO APPLICABLE TO OTHER PURPOSES."
Our Invention consists, firstly, in using for the treatment or purification of
sewage and other matters, by precipitation or otherwise, solutions of hydrofluosilicic
acid, hydrofluoboric acid, and the fluorides, the silicofluorides, borofluorides, tantalo-
fluorides, and titanofluorides of aluminium, iron, manganese, and zinc, and solutions
of slag lava, Farnham rock, and cryolite in hydrochloric acid as herein-after
described.
Such of the aforesaid compounds as are soluble in water we add direct to the
sewage to be purified. Such of them as are solid we dissolve in water, or, if
necessary, in some suitable acid (preferably hydrochloric or sulphuric acid), and we
add any or all of the resulting solutions either by itself or themselves or in con-
junction or admixture with charcoal, clay, and blood, or with charcoal or clay, or
with other agents, to the sewage to be treated or purified, and when necessary we
add to such sewage (either before or after adding the aforesaid agents) lime or
other alkaline earth or alkali in such proportion that the sewage shall be neutral.
[Price Adl

page_text: Or the lime or other alkaline earth or alkali may be first mixed with the clay and
charcoal and added to the sewage before the other agents are added.
Our Invention consists further in preparing hydrofluosilicic acid by heating a
mixture of ground fluor spar and sand in a current of superheated steam.
Our Invention consists further in preparing the fluorides or silicofluorides of
aluminium aforesaid by digesting in hydrofluoric or hydrosilicofluoric neid, dried
clay, granulated slags, lava, and such other minerals (such as Farnham rock) as are
composed in great measure of silica and alumina, and contain but little lime."
Our Invention consists further in preparing the fluoridles or silicofluorides of iron
by digesting the burnt iron pyrites from vitriol works (which pyrites is at present
a waste substance) in hydrofluoric or hydrofluosilicic acid, or by digesting iron ores
in either of the said acids.
Our Invention consists further in preparing the fluorides and silicofluorides of
manganese and zinc by digesting ores or refuse products containing either of these
metals in hydrofluoric or hydrofluosilicic acid respectively.
Our Invention consists further in preparing titanofluoride of iron and alumina by
digesting titaniferous iron, sand, or other titaniferous iron ores or titaniferous clays
in hydrofluoric acid.
Our Invention consists further in dissolving in hydrofluoric acid slags, lava,
Farnham rock, or cryolite, or other minerals of similar composition, and using the
resulting products as substitutes for alum, sulphate of alumina, and other salts of
alumina, or alum sludge, in the treatment or purification of sewage.
Our Invention consists further in mixing the aforesaid fluosilicic acid, or the
hydrofluoboric acid, or the fluorides, silicofluorides, tantalofluorides, or titano-
fluorides of iron, manganese, or zinc, or the solutions of slag, lava, Farnham, rock,
or cryolite aforesaid with charcoal, sawdust, or other suitable absorbent, so as to
make a mixture in a solid form which is more convenient for transport than a
fluid.
Our Invention consists further in the preparation of an improved charcoal, which
may be used in the purification of sewage, by precipitation, filtration, or otherwise,
and for other purposes. We prepare the said charcoal as follows:-We mix sewage
deposit, or precipitate, or pond or river mud, containing carboniferous and
nitrogenous matters in sufficient quantity, or the carboniferous residue of oil shales
or spent dye-woods, or spent tan, or pent, or saw dust, or sea weed, or other suitable
carbonaceous matter with (by preference) phosphates of lime, or of magnesia, or of
iron, or of alumina (dissolved if necessary in sulphuric acid), or with sulphate of
lime, or with sulphate of magnesia, or we mix any of the said sulphates or phosphates
with any one, two, or more of the carbonaceous matters enumerated, and we dry
and carbonize in the usual way the mixture or mixtures thus made, and thus obtain
charcoal of various kinds which is very useful for deodorizing and decolourizing
purposes, innsmuch as it approaches in its composition and properities animal
charcoal, which is more efficacious than any other charcoal for many purposes, but
which owing to its high price cannot be advantageously used for the treatment of
sewage. In addition to increasing the purifying power of the charcoal we by thus
including the aforesaid phosphates in its composition also increase the manurial value
of the resulting sewage deposit.
We obtain the said phosphates by dissolving in sulphuric acid coprolites, apatite,
natural phosphate of alumina, vivianite, and other similar phosphatic minerals, but
we do not limit ourselves to any particular source or preparation of the said
phosphates.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Christopher Rawson and John William Slater in the Great Seal
Patent Office on the 4th November 1876.
CHRISTOPHER RAWSON, of No. 9, Victoria Chambers, in the City of Westminster,
Managing Director of the Native Guano Company (Limited), and JOHN WILLIAM
SLATER, of No. 2, Tamworth Terrace, in the County of Middlesex, Analytical
Chemist "IMPROVEMENTS IN THE TREATMENT OR PURIFICATION OF SEWAGE AND
OTHER MATTERS, AND IN THE PREPARATION OF AGENTS TO BE USED IN SUCH
TREATMENT, SOME OF WHICH ARE ALSO APPLICABLE TO OTHER PURPOSES."
Our Invention consists, firstly, in using for the treatment or purification of
sewage and other matters, by precipitation or otherwise, hydrofluoboric acid, and
the fluorides, borofluorides, tantalofluorides, and titanofluorides of aluminium, iron,
manganese, and zinc, and a solution of cryolite in hydrochloric acid as herein-after
described.
We prefer to dissolve in water such of the aforesaid matters as are soluble in
water to a sufficient extent so as to make solutions of such matters, and wo
dissolve in suitable acids (preferably hydrochloric or sulphuric acid) such of the
said matters as are insoluble in water, or not soluble to a suflicient extent in water,
and we add any or all of the resulting solutions, either by itself or theinselves,
or in conjunction or admixture with charcoal, clay, and blood, or with charcoal or
clay, or with other agents, but in substitution for alum sulphate of alumina or
muriate of alumina, or other salts of alumina, or alum sludge to the sewage to bo
treated or purified, and when necessary we add to such sewage (either before or after
adding the aforesaid agents) lime or other alkaline earth or alkali which does not
when treated with acid give off carbonic acid gas, the matters so treated being in
such proportion that the effluent water shall be neutral. Or the lime or other
alkaline earth or alkali may be first mixed with the clay and charcoal and added to
the sewage before the other agents are added.
Or instead of dissolving in water such of the aforesaid matters as are soluble
in water, and adding the resulting solution or solutions to the sewage, we add such
matters in a solid state to the said sewage. The proportious of the aforesaid
matters must be varied according to the nature of the sewage to be trented.
In practice we find the following proportions give good results with ordinary
house sewage. We add to every 1,000 gallons of such sewage from 4 to 6 pounds of
hydrofluoboric acid, or of the borofluorides, tantalofluorides, and titanofluorides of
aluminium, iron, manganese, or zinc (dissolved if necessary in the smallest possible
quantity of sulphuric or hydrochloric acid), or of cryolite dissolved in hydrochloric
acid or of any mixture of these matters, or when we use such of the aforesaid
matters as are soluble in water we add from 4 to 6 pounds of such matters or of
any mixture of such matters in a solid state to the said sewage.
In treating such sewage as contains refuse water from tan yards or dye works,
or other water containing astringent vegetable matter, we avoid the use of the com-
pounds of iron herein-before referred to.
When we use the aforesaid hydrofluoboric acid and the fluorides, borofluorides,
tantalofluorides, and titanofluorides of aluminium, iron, manganesc, and zinc, and
the solution of cryolite in addition to or admixture with deodorizing or purifying
mixtures, which as ordinarily made contain alum, sulphate of alumina, muriate of
alumina, or other salts of alumina, or alum sludge, we omit these agents and add
in lieu thereof the aforesaid hydrofluoboric acid or the fluorides, borofluorides,
tantalofluorides, or titanofluorides of aluminium, iron, manganese, and zinc, or the
solution of cryolite (any of these matters or any mixture of them), the proportion
in which they added being from 4 to 6 pounds of such matters or any of them (in
addition to the other agents contained in the mixture) to every 1,000 gallons of.
sewage to be treated.

page_text: The following is an example of the proportions and constituents of a deodorizing
and purifying mixture which we find to answer well in practice :-
Hydrofluoboric acid
Charcoal (by preference of the kind herein-after
6 lbg.
20
31
- 70 grains by weight.
Clay free from alkaline earthy carbonates -
Blood
The blood may be omitted from this mixture if a very bright effluent be not
required. This mixture will be sufficient for 1,000 gallons of sewage.
We prepare the fluorides of aluminium by digesting dried clay in hydrofluoric
acid.
We prepare the fluorides of iron by digesting the burnt iron pyrites from vitriol
works (which pyrites is now a waste substance) in hydrofluoric acid. The said
fluorides may, however, be prepared by digesting iron ores in the said acid or in any
other way.
Wo prepare the fluorides of manganese and zinc by digesting refuse products
containing either of these metals in hydrofluoric acid.
We prepare the titanofluoride of iron by digesting titaniferous iron, sand, or
titaniferous iron ores in hydrofluoric acid.
The aforesaid hydrofluoboric acid or the fluorides, tantalofluorides, or titano-
fluorides of iron, manganese, or zinc, or the solution of cryolite (any or all of them)
may be mixed with charcoal or other suitable absorbent so as to make a mixture
in a solid form, which is more convenient for transport than a fluid.
68
Our Invention consists further in the preparation as herein-after described of an
improved charcoal which may be used as a substitute for animal charcoal or
bone-black" in the purification of sewage by filtration, or as a substitute for the
charcoal or waste carbon used in processes in which the sulphates, muriates, nitrates,
or acetates of alumina or iron are used for purifying sewage and other matters.
Our said improved charcoal may also be used with advantage in admixture with
the fluorides herein-before referred to for the purification of sewage and other
matters. We prepare our improved charcoal as follows:-We take sewage deposits
or precipitates, or pond or river mud, containing carboniferous or nitrogenous
matters in sufficient quantity, or we tako spent dye-wood, and pent, tan, or saw-
dust, or seaweed, or other carbonaceous wasto substances (always excluding such as
are of a bituminous or resinous nature) any or all of these (with the foregoing
exception) and we mix it or them with the phosphates of lime, magnesia, iron, and
alumina dissolved in sulphuric acid or with any one or more of them. We then dry
the resulting mass and char it in closed vessels at the lowest temperature that is con-
sistent with proper carbonization. The proportions of the ingredients which we
prefer are such that the charcoal obtained may contain from 10 to 25 per cent. of
mineral matter.
We are aware that it has been proposed to prepare certain compound charcoals
by mixing and carbonizing chalk, lime, magnesian limestone, and magnesia and clay
with vegetable refuse, thus producing a charcoal having an alkaline reaction when
added to sewage. We are aware also that it has been proposed to mix carbonaceous
matters with phosphates of lime and alumina not dissolved in acids but in the
state of powder or pulp, and generally containing carbonates. We, however, care-
fully avoid the presence of carbonates, hydrates, or oxides of calcium and magnesin,
and if such substances are present in our raw material, they are destroyed by the
sulphuric acid which we employ. The charcoal which we produce is not alkaline
but neutral or even slightly acid, and we employ it not as a precipitant nor as an
alkaline addition for neutralizing acid phosphates of lime or alumina used as
precipitants. We regard it merely as a kind of charcoal which is suitable for use
in substitution for animal charcoal in absorbing sewage gases and any liquid
colouring or inal-odourous matters which the sulphates, muriates, nitrates, and ace-
tates of alumina and iron or other precipitants fail to precipitate.

page_text: ->
Having now described the nature of our Invention and the manner in which
the same is to be performed, we wish it to be understood that we do not limit
ourselves to the precise details and proportions herein-before described, as they may
be varied without departing from the nature of our said Invention, neither do wo
limit ourselves to the use of fluorides, borofluorides, tantalofluorides, and titano-
fluorides of aluminium, iron, manganese, and zinc prepared by the processes herein-
before described, as these agents may be prepared by other processes. But we
claim as our said Invention-
Firstly. Using hydrofluoboric acid, and the fluorides, borofluorides, tantalo-
fluorides, and titanofluorides of aluminium, iron, manganese, and zinc, and the
aforesaid solution of cryolite (any or all of them) as a substitute or substitutes
for alum, sulphate of alumina, muriate of alumina, and other salts of alumina and
alum sludge, in the treatment of sewage and other matters essentially as licrein-
before described.
c.
Secondly. The preparation of an improved kind of charcoal as herein-before
described, and its use for decolourizing and deodorizing purposes, and especially
as an adjunct in the treatment of sewage and other matters.
In witness whereof, I, the said John William Slater, have hereunto set my
hand and seal, this. Third day of November, in the year of our Lord One
thousand eight hundred and seventy-six.
Witness,
"
H. H. MURDOCH,
7, Staple Inn.
London.
J. W. SLATER. (L.S.)