IMPROVEMENTS IN TREATING AND UTILIZING SEWAGE
Year: 1873

page_text: LETTERS PATENT to Alexander Colvin Fraser, of New Barnet, in the
County of Herts, Engineer, and William Watson, of Great Ayton,
near Northallerton, in the County of York, Chemist, for the In-
vention of IMPROVEMENTS IN TREATING AND UTILIZING SEWAGE,
PROVISIONAL SPECIFICATION left by the said Alexander Colvin
Fraser and William Watson at the Office of the Commissioners of
Patents, with their Petition, on the 7th November 1873.
We, ALEXANDER COLVIN FRASER, of New Barnet, in the County of
Herts, Engineer, and WILLIAM WATSON, of Great Ayton, near North-
allerton, in the County of York, Chemist, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN TREATING AND UTILIZING
SEWAGE," to be as follows:-
The object of this Invention is to render sewage commercially
available in the manufacture of artificial manure and other manufac-
turing purposes by the economical elimination and treatment of the
organic and oleaginous elements of the sewage, for which purpose we

page_text: employ aluminous schistus and the analogous oil or jet rock calcined
under atmospheric influence by the aid of peat, wood, or coal bats, the
combined properties of which are sulphate of alumina, sulphate of iron,
sulphate of magnesia, and sulphate of lime, with that of vegetable
carbon.
The above combined elements we, when necessary, saturate with
dilute sulphuric acid, and intermix with clay, sulphate of lime, or
prepared dry mould, to ensure the more efficient development of their
properties when brought in contact with the mass of sewage.
Our improved preparation may be applied to the treatment of the
sewage in any convenient way, preferring to form the same into filter
beds, through which the sewage to be utilized is caused to percolate; or
the preparation may be used in a pulverized state, and thoroughly mixed
with the sewage in suitable tanks or reservoirs so mechanically arranged
that the effluent water may readily make its escape therefrom. The
preparation so made use of for the decomposition of sewage and the
deposition of its organic and oleaginous properties may in conjunction
with the combined matters by it absorbed be treated and used as a
manure, or may be subjected to calcination in suitable retorts, so that
the residuum may be applied as a combined carbon for foundry and
other purposes.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Colvin Fraser and William Watson in
the Great Seal Patent Office on the 7th May 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ALEX-
ANDER COLVIN FRASER, of New Barnet, in the County of Herts,
Engineer, and WILLIAM WATSON, of Great Ayton, near Northallerton,
in the County of York, Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of November, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and suc
cessors, give and grant unto us, the said Alexander Colvin Fraser, and
William Watson, Her special license that we, the said Alexander

page_text: Colvin Fraser, and William Watson, our executors, administrators, and
assigns, or such others as we, the said Alexander Colvin Fraser and
William Watson, our executors, administrators, and assigns, should at
any time agree with, and no others, from time to time and at all
times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN TREATING AND UTILIZING SEWAGE," upon
the condition (amongst others) that we, the said Alexander Colvin
Fraser and William Watson, our executors or administrators, by an
instrument in writing under our or their hands and seals, or under the
hand and seal of one of us or them, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
same was to be performed, and cause the same to be filed in the
Great Seal Patent Office within six calendar months next, and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexander Colvin Fraser, for
myself and on behalf of the said William Watson, do hereby declare
the nature of the said Invention, and in what manner the same is to bo
performed, to be particularly described and ascertained in and by the
following statement thereof (that is to say) :-
The object of this Invention is to render sewage commercially
available in the manufacture of artificial manure and other manufac-
turing purposes by the economical elimination and treatment of the
organic and oleaginous elements of the sewage, for which purpose wo
employ aluminous schistus and the analogous oil rock or jet rock cal-
cined under atmospheric influence by the aid of peat, wood, or coal bats,
the combined properties of which preparation or calcined compound are
sulphate of alumina, sulphate of iron, sulphate of magnesia, and
sulphate of lime, with that of vegetable carbon.
The preparation or calcined compound containing the above-named
combined elements we, when necessary, saturato with dilute sulphuric
acid, and intermix with clay, sulphate of lime, or prepared dry mould, to
ensure the more efficient development of their properties when brought
in contact with the mass of sewage.
Our improved preparation may be applied to the treatment of the
sewage in
any convenient way, preferring to form the same into filter.

page_text: beds, through which the sewage to be utilized is caused to percolate; or
the preparation may be used in a pulverized state, and thoroughly mixed
with the sewage in suitable tanks or reservoirs, so mechanically arranged
that the effluent water may readily make its escape therefrom. The
preparation so made use of for the decomposition of sewage and the
deposition of its organic and oleaginous properties may, in conjunction
with the combined matters by it absorbed, be treated and used as a
manure, or may be subjected to calcination in suitable retorts, so that
the residuum may be applied as a combined carbon for foundry and
other purposes.
3 In carrying out our Invention we take the aluminous schistus as
excavated from the rocks, and place it in heaps over some burning body;
it may be of peat, wood, coal bats, and oil rock or jet rock, it being
necessary to form air passages with bricks so placed at the bottom as to
supply air to the centre of the heap and support combustion. We go on
adding alternate layers of aluminous schistus interspersed with the fuel
requisite to keep the whole mass burning, such fuel being in about equal
proportions of peat, wood, coal bats, and oil rock or jet rock, and this has
to be continued until, by reason of the size of the heap, the labour comes
to be too costly in heaping up the materials together, when the mass is
allowed gradually to extinguish itself, as the products of combustion
have been exhausted. Then we have obtained our preparation or cal-
cined compound ready for treating with sulphuric acid, in cases where
sulphuric acid is to be used, and which we prefer to apply whilst the
preparation or compound is still in a slightly heated state. We prefer
to apply the acid after it has been diluted in the proportion of 6 lbs. or
thereabouts of sulphuric acid of specific gravity 1.60, diluted with four
gallons of water to every ton weight of the preparation or calcined
compound.
We apply the dilute sulphuric acid to our preparation or calcined
compound by means of pans, having suitable roses through which the
sulphuric acid is poured, so that it is spread over the whole surface of
the particles of the preparation or compound, which we at the same
time keep turning over to ensure that all the surfaces of the particles of
the preparation shall be saturated with the dilute sulphuric acid.
Our improved preparation or calcined compound may be used undi-
luted when employed for treating sewage containing only a small
portion of organic matter, but when treating sewage containing any

page_text: considerable proportion of organic matter we saturate the calcined
compound with sulphuric acid as above mentioned, the quantity of
sulphuric acid being increased according to the proportion of impurity
contained in the sewage to be treated.
We have found it advantageous to use muriatic acid in combination
with the sulphuric acid in about equal proportions by weight.
We have tested our Invention in practice as applied to sewage of
two different kinds, namely, sewage obtained from the district of
Barnet, in the County of Herts, and sewage obtained from the district of
Leeds, in the County of York.
In treating sewage of the Barnet district, which contains only a
small quantity of organic and oleaginous matter, we in the first place
lead the sewage into a mixing tank, into which we then feed our
preparation or compound, the sewage in the tank being kept in a
state of constant agitation, so as to thoroughly incorporate it with our
preparation or compound, which we use in the proportion of about one
pound by weight of the preparation or compound to every one hundred
gallons of sewage. When the mixture in these proportions has been
thoroughly effected, the contents of the tank are permitted to flow into
a settling reservoir, in which reservoir there are a series of subdivisions
or walls resting on the bottom thereof, and which are placed at right
angles to the direction of the flowing sewage, so that as each of the
chambers so formed gets charged with the mixture, the latter overflows
into the next chamber, and so on, four or other convenient number of
chambers being employed. The overflow from these chambers passes on
to and through an adjoining filter bed composed as follows:-First, a
bottom layer resting upon perforated plates and composed of rounded
pebbles mixed with a small quantity of lime, the depth of this layer
being about nine inches; second, on the layer just described a layer
about six inches deep of our preparation or calcined compound roughly
ground; thirdly, on the top of the layer just described a layer about
four inches deep of peat charcoal or other charcoal; and lastly, a top
layer of fine river washed sand. By this plan the effluent water will be
found to run off clear and free from any odour or disagreeable taste.
In treating sewage from the Leeds district, which is highly impreg-
nated with organic and oleaginous matters, and much discolored, the

page_text: samples we have treated being nearly as dark as ink, we have obtained
very good results in a similar manner to that above described, but we
have found it necessary to use slightly increased quantities of the
sulphuric acid and of the lime. We have also used muriatic acid with
advantage in treating this sewage.
The residuum which accumulates in the chambers of the settling
reservoir as aforesaid we remove periodically and dry by exposure to the
atmosphere or by other convenient process of drying, then intermix it
with a small quantity of lime to form a valuable fertilizing agent or
manure, or we recalcine it in retorts or equivalent apparatus, and subse-
quently grind or pulverize it to form a combined carbon for foundry and
other purposes.
Having described our said Invention of improvements in treating and
utilizing sewage, and having explained the manner of carrying the same
into practical effect, we would have it understood that we do not claim
as of our Invention or the exclusive use of the several substances
herein-before mentioned, except when the same are used in and for the
purposes of our said Invention, which we hereby declare to consist in
the treating and utilizing sewage in the manner above described. We
claim particularly the calcining aluminous schistus, and the analogous
oil rock or jet rock under atmospheric influence by the aid of peat,
wood, or coal bats, and employing the resulting preparation or calcined
compound for treating and utilizing sewage as herein set forth.
In witness whereof, I, the said Alexander Colvin Fraser, have
hereunto set my hand and seal, this Seventh day of May, in
the year of our Lord One thousand eight hundred and seventy-
four