IMPROVEMENTS IN THE TREATMENT AND UTILIZATION OF SEWAGE WATER
Year: 1872

page_text: LETTERS PATENT to Henry Young Darracott Scott, of Ealing, in the
County of Middlesex, Major-General, C.B., for the Invention of
"IMPROVEMENTS
IN THE TREATMENT
AND UTILIZATION OF SEWAGE
WATER."
Sealed the 6th June 1873, and dated the 11th December 1872.
PROVISIONAL SPECIFICATION left by the said Henry Young Dar-
racott Scott at the Office of the Commissioners of Patents, with
his Petition, on the 11th December 1872.
I, HENRY YOUNG DARRACOTT SCOTT, of Ealing, in the County of
Middlesex, Major-General, C.B., do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE TREATMENT AND UTILIZATION OF SEWAGE
WATER," to be as follows:
-
The objects of this Invention are economy in dealing with sewage, the
effectual cleansing of the drains, and the preventing the generation of
noxious sewer gases.

page_text: In carrying out my Invention I discontinue the present system of
supplying the waterclosets and urinals of towns with pure water, and
instead thereof I lay down a service by means of which the sewage
water after clarification and deodorization for the removal of the excreta
of the population can be returned to the houses, and used again.
For the clarification and deodorization of the sewage water I provide
at the outfall two or more tanks or sets of tanks into which the sewage
is run.
In the first of these tanks (say No. 1) I allow precipitation of
the fecal matters to take place after treating the sewage with lime,
lime being a very efficient and the most economical agent for the
purpose.
On first commencing the operation double the requisite amount of
lime for the defecation of the sewage is added, and tank No. 2 is not
employed, but the clarified sewage surcharged with lime is pumped
up and conveyed in suitable pipes back to the town and supplied to the
closets either on the continuous or intermittent system. This sewage
water containing in solution enough free lime to defecate and deodorize
a first volume of excreta then flows back to and settles in tank No. 1,
cleansing the drains in its course, and effectually preventing those
accumulations of glutinous nitrogen compounds which make sewer
gases so dangerous to health by their putrefactive decomposition. It is
these accumulations also which render the first storm waters from
sewers so noxious and filthy, and by the proposed treatment, as no such
lodgments take place on the sides and bottom of the sewers, the first
storm waters will consist only of very diluted fresh sewage.
The matters first deposited in tank No. 1 having been collected, dried,
and burned to lime by well-known methods, this lime, mixed with such
an additional quantity of ordinary lime as will suffice to defecate a third
volume of sewage, is now stirred in with the sewage effluent from tank
No. 1, and after the subsidence of the insoluble particles in tank-No. 2
is again pumped back to the town to be thrown into the waterclosets as
before.
The undissolved residue which remains.in tank No. 2 (consisting chiefly
of silicate and phosphate of lime with notable quantities of nitrogenous

page_text: A portion of the sewage water on its return flow into the town may be
utilized by market gardeners and for pleasure grounds, and having
sufficient head to command much of the agricultural land in the neigh-
bourhood may be advantageously used for irrigation.
As the sewage water, if allowed to run into the ordinary drains
or sewers, will receive continual additions from subsoil drainage,
surface water, and water which has been used for domestic purposes,
such as for washing and cooking, it will be necessary to provide an
outlet for such excess of water as cannot be advantageously employed for
the closets or for irrigation purposes. As much as flows between
12 o'clock at night and six o'clock in the morning, consisting mainly of
subsoil water flowing through perfectly clean drains, may be discharged
without much harm into the nearest watercourse, or it may be filtered
through a small area of ground.
The remainder of the excess is purified by chemical processes, and its
ammonia extracted by a process for which I have already obtained
Letters Patent; or this operation may be effected by any other method,
as the water flows from tank No. 1 after the extraction of its suspended
matters. It is then allowed to pass away into the nearest watercourse,
or may be used for irrigation.
The action of the lime on the sewage water will convert much of the
nitrogen compounds into ammonia, but this substance will also to some
extent be expelled by it; I therefore provide ventilating shafts along
the lines of the main sewers, and at the summit level. In these shafts
is placed coke moistened with acid or other substances which can
absorb and retain ammonia.
In the cisterns and also in the pans of closets the film of carbonate of
lime which rapidly forms will prevent the escape of ammonia at these
points.
By the above means the present serious evil of the pollution of rivers
by town sewage will be completely remedied without entailing any
expense on communities. The value of the sewage merely as water for
the supply of closets for flushing purposes, where the existing drains
are badly laid, would cover the expense of any alteration required by
my Invention.
The value of the water for irrigation purposes, commanding as it
would (from the high level to which it is raised) the best ground in the

page_text: neighbourhood for taking it, and the value of the ammonia which
in the more concentrated form in which it would exist in such sewage
water could be readily extracted by the process indicated, would amply
repay the cost which towns would have to encounter in laying down the
new service, and for the erection of pumping works.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Young Darracott Scott in the Great Seal
Patent Office on the 11th June 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
YOUNG DARRACOTT SCOTT, of Ealing, in the County of Middlesex,
Major-General, C.B., send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eleventh day of December, in the year
of our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said Henry Young Darracott Scott, Her
special licence that I, the said Henry Young Darracott Scott, my
executors, administrators, and assigns, or such others as I, the said
Henry Young Darracott Scott, my 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 King-
lom of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN THE TREATMENT AND UTILIZATION OF
SEWAGE WATER," upon the condition (amongst others) that I, the said
Henry Young Darracott Scott, my executors or administrators, by an
instrument in writing under my, or their, or one of their hands and
seals, 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 immediately after the date of the said Letters
Patent.
•
HAT
TWA
11

page_text: the same is to be performed, to be particularly described and ascertained
in and by the following statement (that is to say) :-
The objects of this Invention of improvements in the treatment and
utilization of sewage water are, 1, econony in dealing with sewage;
2, the effectual cleansing of the drains; and 3, the preventing the genera-
tion of noxious sewer gases.
In carrying out my Invention I discontinue the present system of
supplying the waterclosets and urinals of towns with pure water, and
instead thereof I lay down a service by means of which the sewer water
after clarification and deodorization for the removal of the excreta of the
population can be returned to the houses and used again.
For the clarification and deodorization of the sewage water, I provide
at the outfall two or more tanks or sets of tanks into which the sewage
is run. In the first of these tanks (say No. 1) I allow precipitation of
the focal matters to take place after treating the sewage with lime, lime
being a very efficient and the most economical agent for the purpose.
On first commencing the operation double the requisite amount of
lime for the defecation of the sewage is added, and tank No. 2 is not
employed, but the clarified sewage (surcharged with lime) is pumped up
and conveyed in suitable pipes back to the town, and supplied to the
closets either on the continuous or intermittent system. This sewage
water containing in solution enough free lime to defecate and deodorize
a fresh volume of excreta, &c., then flows back to and settles in tank
No. 1, cleansing the drains in its course, and effectually preventing those
accumulations of glutinous nitrogenous compounds which make sewer
gases so dangerous to health by their putrefactive decomposition. It is
these accumulations also which render the first storm waters from sewers
so noxious and filthy. As by my novel treatment of the sewage waters
no such lodgments take place on the sides and bottom of the sewers the
first storm waters will consist only of very diluted fresh sewage.
The matters first deposited in tank No. 1 having been collected, dried,
and burned to lime by well-known methods, this lime, mixed with such
an additional quantity of ordinary lime as will suffice to defecate a third
volume of sewage, is now stirred in with the sewage effluent from tank
No. 1, and after the subsidence of the insoluble particles in tank No. 2, .
the sewage effluent is again pumped back to the town in order to be
used in the waterclosets as before.

page_text: The undissolved residue which remains in tank No. 2 (consisting
chiefly of silicate and phosphate of lime, with notable quantities of
nitrogenous organic matter) will afford a valuable manure. It is there-
fore collected, dried, and sold or used for that purpose.
A portion of the sewage water on its return flow into the town may be
utilized by market gardeners and for pleasure grounds, and having
sufficient head to command much of the agricultural land in the
neighbourhood may be advantageously used for irrigation.
As the sewage water if allowed to run into the ordinary drains or
sewers will receive continual additions from subsoil drainage as well as
from surface water, and water which has been used for domestic
purposes (such as for washing, cooking, &c.), it will be necessary to
provide an outlet for such excess of water as cannot be advantageously
employed for the closets or for irrigation purposes. As much water as
flows between twelve o'clock at night and six o'clock in the morning,
consisting mainly of subsoil water flowing through perfectly clean
drains, may
be discharged without much harm into the nearest water-
course, or it may be filtered through a small area of ground.
The remainder of the excess is purified by chemical processes, and its
ammonia extracted by a process for which I have, already obtained
Letters Patent, or this operation may be effected by any other method
as the water flows from tank No. 1 after the extraction of its suspended
matters. It is then allowed to pass away into the nearest watercourse,
or may be used for irrigation.
The action of the lime on the sewage water will convert much of the
nitrogen compounds into ammonia, but this substance will also (to some
extent) be expelled by it. I therefore provide ventilating shafts along
the lines of the main sewers and at the summit level. In these shafts is
placed coke moistened with acid or other substances, which can absorb
and retain ammonia.
In the cisterns and also in the pans of closets the film of carbonate of
lime which rapidly forms will prevent the escape of ammonia at these
points.
By the above means the present serious evil of the pollution of rivers
by town sewage will be completely remedied without entailing any
expense on communities. The valve of the sewage merely as water for

page_text: the supply of closets and for flushing purposes (where the existing
drains are badly laid) would cover the expenses of any alteration
required by my Invention.
The value of the water for irrigation purposes, commanding as it
would (from the high level to which it is raised) the best ground in the
neighbourhood for taking it, and the value of the ammonia which (in
the more concentrated form in which it would exist in such sewage
water) could be readily extracted by the process indicated, would amply
repay the cost which towns would have to encounter in laying down the
new service, and for the erection of pumping works.
Having now described my Invention of improvements in the treatment
and utilization of sewage water, and having explained the manner of
carrying the same into effect, I claim as the Invention secured to me by
Letters Patent as aforesaid, treating sewage water in the manner herein
set forth, and utilizing the clarified effluent water for flushing, irrigation,
and watercloset purposes by causing it, when properly clarified, to be
conveyed back again in suitable service pipes either to houses where it
may be again used in the waterclosets, or to any other place or places
where it may be used for any of the purposes above mentioned.
In witness whereof, I, the said Henry Young Darracott Scott, have
hereunto set my hand and seal, the Eleventh day of June, in
the year of our Lord One thousand eight hundred and seventy-
three.