IMPROVEMENTS IN TREATING SEWAGE WATER AND OTHER LIQUIDS CONTAINING AMMONIA "
Year: 1883

page_text: LETTERS PATENT to James Young of Kelly, in the County of Renfrew, North
Britain, Doctor of Laws for an Invention of "IMPROVEMENTS IN TREATING
SEWAGE WATER AND OTHER LIQUIDS CONTAINING AMMONIA
"
PROVISIONAL SPECIFICATION left by the said James Young at the Office
of the Commissioners of Patents on the 26th January 1883.
JAMES YOUNG of Kelly in the County of Renfrew North Britain Doctor of
Laws IMPROVEMENTS IN TREATING SEWAGE WATER AND OTHER LIQUIDS
"
CONTAINING AMMONIA
"
This invention relates to apparatus for the purpose of carrying into effect the
process of treating Sewage water and to the method and conditions of working the
same and which process is also applicable to the treatment of other liquids
containing ammonia in respect of which Letters Patent N° 3562 were granted to
me dated the 27th day of July A.D. 1882.
By my present invention I construct the vessels in which the Sewage or other
water is treated in the form shewn in the accompanying Drawing or some
equivalent form and connect them as therein shewn so that the sewage or other
water flows through the series of vessels in the contrary direction to that in which
the steam goes from vessel to vessel. In this way the sewage or other water can
be allowed to flow continuously through the series of vessels and will be discharged
at the last one in a state in which it is less offensive.
By another portion of my Invention I do not employ a continuous system of
supply but charge a series of vessels similar to those above referred to and connected
in a similar way but without the inlet and outlet pipes for the liquid under
treatment or the water communications between the vessels depicted in the
drawings When the ammonia in the boiler into which the steam first enters is
sufficiently extracted the communication with the next boiler is cut off and the
boiler discharged and charged with fresh liquid and it is then connected with the
series so as to be the last of the series instead of the first.

page_text: Before the Sewage water is thus treated the solid matter may be thrown down
by lime or other suitable alkali or alkaline earth and the ammonia is also thereby
liberated after which I prefer to draw off the water to be treated as above described
leaving the sediment behind.
I propose to arrange air pumps and fans in the tubes by which the steam passes
from one boiler to the other so as to draw off the steam from one boiler and force
it into the next and I propose to make it pass through sulphuric or any other
suitable acid in its path by which the ammonia is extracted or removed whilst the
steam freed from Ammonia passes on and may be further utilized.
I may use steam or air or a mixture of the two-And I propose to conduct the
process at a low pressure and correspondingly low the latter not higher than 60°
to 90° Fahrenheit if requisite. The lowness of the temperature is of great
importance to the economy of the process.-The pressure and temperature are
lowered and kept low by maintaining a sufficient vacuin in the apparatus

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by The Right Honorable Lyon Playfair, Robert Angus Smith and James
Duncan, Executors and Trustees of the said James Young, deceased, in the
Great Seal Patent Office on the 25th July 1883.
The Right Honorable LYON PLAYFAIR C.B. and M.P., ROBERT ANGUS
SMITH L.L.D. and F.R.S. residing in Manchester, and JAMES DUNCAN of Benmore
in the County of Argyll Executors and Trustees of James Young late of Kelly in
the County of Renfrew, North Britain, Doctor of Laws, Deceased. "IMPROVEMENTS
IN TREATING SEWAGE WATER AND OTHER LIQUIDS CONTAINING AMMONIA
"
This Invention relates to apparatus and to the method and conditions of working
the same, for the purpose of carrying into effect the process of treating sewage
water and other liquids containing ammonia in respect of which Letters Patent
were granted to the said James Young No. 3562. dated 27th, day of July A.D. 1882.
It is connected with the Invention for which Letters Patent were granted to the
said James Young No. 4659, A.D. 1882, and also with a third for which Letters
Patent were granted to the said James Young No. 332, A.D. 1883, all three bearing
upon the same subject.
The above mentiond process of treating sewage and other liquids containing
ammonia, consists in exposing the liquid to the action of steam in as complete n
vacuum as is practically obtainable so that the ammonia is eliminated from the
liquid without raising its temperature above 60° or 90° Fahrenheit, this being the
temperature at which water boils under the diminished pressure at which it is
proposed to work the process.
By the present Invention the vessels in which the sewage or other water is
treated are so constructed and the said vessels so connected that the sewage or
other water flows through the series of vessels in the contrary direction to that in
which the steam goes from vessel to vessel.-In this way the sewage or other water
can be allowed to flow continuously through the series of vessels and discharged
from the last one almost free from ammonia and in a state in which it is less
offensive.
By another portion of this Invention a continuous system of supply is not
employed, but a series of vessels, similar to those above referred to and connected
in a similar way but without the inlet and outlet pipes for the liquid under
treatment or the water communications between the vessels, is charged.-When
the ammonia in the boiler into which the steam first enters is sufficiently extracted,
the communication with the next boiler is cut off and the boiler discharged of the
spent liquid and recharged with fresh liquid and it is then connected with the
series, so as to be the last of the series instead of the first.
A sheet of drawing is appended hereunto in which is shewn an apparatus
consisting of a series of vessels and connections by means of which the continuous
boiling and distillation of the sewage, in a partial vacuum according to the first
part of this said Invention can be conveniently carried out. In actual practice
these vessels will be made of metal, concrete or other suitable material, of strength
sufficient to withstand the external pressure.-The apparatus shewn consists of
four upright cylindrical vessels respectively marked A, B, C, and D, but there may
be a greater or less number of such vessels with the various pipes and connections
to be hereinafter described.-A sufficient vacuum having been obtained in the
apparatus by means of a vacuum pump communicating with the pipe N, leading
from the vessel A, the sewage is caused to flow into the apparatus though the
inlet E. The sewage rises in the vessel A, until it reaches the level of the stand-

page_text: pipe or overflow F, down which it falls and fills the vessel B, up to the height of
its overflow G, down through which the sewage again falls and fills the vessel C,
up to the height of its overflow H, when the sewage again falls therethrough and
fills the vessel D, up to the height of its stand-pipe or overflow pipe I.-It will be
observed that the level of the stand-pipe or overflow F, is higher than the
overflow or stand pipe G, that G, is higher than H, and H, higher than I, so that
the level of the liquid in the vessel A, is maintained higher than that in the
vessel B, the level in B, higher than that in the vessel C, and the level in C,
higher than that in the vessel D.-The object being to overcome the steam pressure
produced by the dip of the steam pipes below the level of the liquid in each
vessel. It may be found preferable to keep the water-level and overflow pipe at
the same distance from the bottom of each vessel, and fix the vessels themselves
on different levels, rising from D, to A, in order to allow the liquid to flow
through the apparatus in opposition to the pressure exerted by the steam.-Into
the upper part of the vessel D, a steam inlet pipe J, passes, the pipe dipping a
convenient distance below the level of the sewage therein; a similar pipe K, leads
from the vessel D, to a similar distance below the level of the sewage in the
vessel C, from the top of which another similar pipe L, leads, that likewise dips
into the sewage in the vessel B, from which another such pipe M, leads and dips
into the sewage in the vessel A.-The upper part of the vessel A, is connected by
the pipe N, to a vacuum pump.
The action of the apparatus is as follows:-The several vessels A, B, C and D,
being more or less exhausted of air and charged with sewage as herein before
described and shewn on the accompanying drawing.-The liquid in each vessel is
heated to the temperature at which steam will pass through it without
condensation at the low pressure obtained in the vessels, (if the liquid has not
been introduced at the proper temperature).-Steam is admitted to the vessel D,
through the steam inlet J.-This non-condensation temperature, or as it may be
called, the boiling point of the liquid, will vary according to the perfection of the
vacuum obtained. At a pressure of half an inch of mercury the temperature will
be about 60° Fahrenheit, while at one inch pressure it will be nearly 80°
Fahrenheit. So that a high vacuum is of the greatest importance in regard to
the economy of the process.-The steam after being admitted through the steam
inlet J, passes through the liquid in each of the four vessels D, C, B, and A,
consecutively by the pipes J, K, L and M, and finally leaves the apparatus by the
steam outlet N, in the direction of the vacuum pump.
The ammonia contained in the sewage as well as other volatile substances are
carried out of it by the steam or low pressure aqueous vapour passed through the
vessels A, B, C, and D, so that whilst the sewage in the vessel A, contains the
maximuin quantity of the ammonia and other substances removed by the passing
of aqueous vapour through the vessels; the vessels B, C, and D, contain
respectively less and less of the ammonia and such substances so separated and the
number of vessels should be such that the liquid in the last vessel thereof, namely,
the vessel D, should be as far as convenient deprived of the ammonia and those
substances which pass off with it. While a continuous current of steam is
passing through the apparatus in the manner described, a continuous supply of
sewage preferably heated to the temperature at which it will boil at the
diminished pressure under which the operation is conducted, is introduced into the
vessel A, through the inlet E, and an equal amount withdrawn through the
outlet O, by means of a pump or otherwise.-Methods for withdrawing the liquid
from the vacuum may be found described in the Specification of the said
James Young filed in pursuance of Letters Patent No. 332. A.D. 1883.-From the
arrangement of the apparatus which has now been described and shewn on the
accompanying Drawing it will be obvious that the sewage flows continuously
through it in one direction in the bottom parts and stand-pipes of the several
vessels whilst low pressure steam passes in the opposite direction in the upper

page_text: parts of such vessels and the several dip pipes J, K, L, and M, wherein a vacuum
more, or less perfect is maintained as herein before described. The directions of
flow of the sewage and steam are indicated by the arrows on the accompanying
drawing. The several dip-pipes are made of large diameter for the purpose of
providing sufficient room for the low pressure steam or aqueous vapour to pass
through. It is also important that they should not dip down further than is
necessary below the surface of the liquid.-The ammonia and other substances
pass off with the aqueous vapour to a condenser or to other collecting apparatus
whilst the uncondensed gases pass off to the vacuum pump which is preferably
kept in continual operation.
In treating sewage by the process just described, it is preferred to add lime in
quantity sufficient to precipitate solid matter dissolved or suspended in the said
sewage and after settling, to draw off the clear liquid for treatment as described.-
By this method the elimination of the ammonia is much facilitated, and the liquid
discharged, with its offensive properties greatly, if not wholly removed.
When liquids other than sewage but containing ammonia are being treated, this
preliminary treatment with lime may, or may not be necessary.-In cases in which
the liquid is alkaline and the ammonia exists in an uncombined state no previous
treatment will probably be required; but where the liquid is acid or the ammonia
combined with other substances, the addition of lime or other alkali or alkaline
earth will probably be necessary.
In working the foregoing process it will be found that the temperature in each
vessel rises from the vessel A, to the vessel D, owing wholly or partially to the
accumulating dip-pressure and friction of the steam in the steam pipes J, K, L,
and M.-To obviate this and to keep the temperatures as low and as uniform as
possible, there may be introduced into the steam-way between each vessel or at
any convenient point, a fan similar in principle to the ventilating fans, now in use
revolving with a rapidity sufficient to withdraw the steam from one vessel and
force it into the next with a pressure equal to the resistance to be overcome.
It being found that steam will take up but a limited quantity of ammonia there
are also introduced "acid traps" at one or more points in its course through a
series of vessels, in which the steam by being brought in contact with sulphuric or
other suitable acid is deprived of the ammonia which it has taken up and is so
enabled to act upon fresh quantities of sewage or ammoniacal liquid in succeeding
vessels.
These "acid traps" and their method of use are further described in the herein-
before referred to Specification N° 332, A.D. 1883.
An admixture of air along with the steam facilitates the expulsion of the
ammonia but also depresses the vacuum, thereby raising the temperature.-In
cases, however, where the pumping power is sufficient to maintain a high vacuum
a small admixture of air with the steam may be found advantageous.
It is important to observe that before allowing the sewage or other liquid to
enter the apparatus bereinbefore described, or analogous apparatus, for treatment
to obtain the ammonia, or for the purpose of condensing the steam, it is advan-
tageous to remove, wholly or partially, any gases which the sewage or liquid may
contain in solution, as these dissolved gases tend to lower the vacuum if they are
allowed to enter the apparatus, and thereby increase the working temperature of
the process-The removal or separation of the gases so held in solution may be
effected by any well known suitable means-either mechanical or chemical,
the means whereby this separation is effected forming no part of the present
invention.
Having now described and particularly ascertained the nature of the said
Invention and the system, mode or manner in or under which the same is or may
be used or practically carried into effect it may be observed in conclusion that in
carrying out the said Invention, the precise form or detail is not limited to that
hereinbefore described as the same may be varied without departure from this

page_text: Invention but what is considered to be novel and original and therefore claimed as
the Invention secured by the hereinbefore in part recited Letters Patent is :-
First: The construction and use of apparatus substantially as herein described
for the purpose of treating sewage water and other liquids containing Ammonia.
Secondly-The arrangement of vessels with inlet and outlet pipes for steam
and fluid shewn in the drawing accompanying this Specification so that the fluid to
be treated can flow continuously through the series of vessels in the contrary
direction to that in which the steam (or the mixture of steam and air) passes
substantially as and for the purposes herein described.
In witness whereof, I the said James Duncan on behalf of myself and the
said Honorable Lyon Playfair and Robert Angus Smith have to this Specification
set my hand and seal this twenty-third day of July One thousand eight hundred
and eighty three.
JAMES DUNCAN (L.S.)