IMPROVEMENTS IN THE DEODORIZATION OF EXCRETA AND IN- THE MANU- FACTURE OF MANURES THEREFROM.
Year: 1873

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 DEODORIZATION OF EXCRETA AND IN- THE MANU-
FACTURE OF MANURES THEREFROM. "
Sealed the 5th August 1873, and dated the 15th February 1873.
PROVISIONAL SPECIFICATION left by the said Henry Young Darracott:
Scott at the Office of the Commissioners of Patents, with his.
Petition, on the 15th February 1878.
I, HENRY YOUNG DARRACOTT SCOTT, of Ealing, in the County of
3 Middlesex, Major-General, C.B., do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE DEODORIZATION OF EXCRETA AND IN THE
MANUFACTURE OF MANURES THEREFROM," to be as follows:-
The object of this Invention is the prevention of nuisance in dealing
with night soil and urinous liquids, and the fixation of their fertilizing
‣ elements, so as to render them valuable marketable commodities.

page_text: In carrying out my Invention with night soil I endeavour, as far as
possible, to separate the solids from the liquids and to extract from the
liquid the phosphoric acid and nitrogen present by means of compounds,
such as lime or magnesia and phosphate of magnesia.
For purposes of deodorization I employ dried sewage deposit, dried
earth, burnt clay, town ashes, saw dust, charcoal, or other deodorants
and absorbents.
In order to arrest the fertilizing elements I employ lime filters which
will decompose the soluble phosphates and retain their phosphoric acid.
The lime filters will also decompose the nitrogenous compounds of the
urine which pass through them with the production of ammonia. Below
the lime filters I employ filters of hydrated phosphate of magnesia,
which will arrest the ammonia (produced by the lime) in the form of
ammoniacal phosphate of magnesia. This process may be used for
treating night soil either in the cesspool or other receptacle, or after it
has been removed therefrom. I sometimes pass the liquid portions
through more than one set of filters, and for the purpose of more
complete purification I add thereto filters of charcoal. One mode of
applying my Invention to cesspools or middens for instance is as
follows: I form in or above the floor of the cesspool a chamber into
and through which the liquid can flow. In this I place a layer of limo
in a granulated condition. This layer may be covered with cocoa-nut
matting, horse hair, cloth, or canvas, and may be preserved from injury
by means of a perforated metal screen or plate, over which I spread a
layer of hydrated phosphate of magnesia and over this a layer of sewage
lime. Another protecting plate may be placed on this lime, and on it is
spread a layer of charcoal. The cesspool or midden when charged as
above is ready for use. The liquid portions of the soil, when deprived of
their fertilizing elements, may then be allowed to pass off.. Filters of
like substances are also applicable to the retention of the fertilising
elements of the urine from public urinals and from stables and other
nitrogenous foul waters.

page_text: 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 15th August 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 Fifteenth day of February, in the year
of our Lord One thousand eight hundred and seventy-three, 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 Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention
for "IMPROVEMENTS IN THE DEODORIZATION OF EXCRETA AND IN THE MANUFACTURE
OF MANURES THEREFROM," upon the condition (amongst others) that I, the
said Henry Young Darracott Scott, my exccutors 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 Offico within six
calendar months next and immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said Henry Young Darracott Scott, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement (that is to say) :--
The object of this Invention is the prevention of nuisance in dealing
with night soil and urinous liquids, and the fixation of their fertilizing
elements, so as to render them valuable marketable commodities.
In carrying out my Invention with night soil I separate the solids
from the liquids, and I use such substances as charcoal, dried earth,

page_text: dried or scorched sewage deposit, sawdust, town ashes, road scrapings,
and other substances of the same class for deodorizing the solids, and I
extract the phosphoric acid and nitrogen present in the liquids by means
of compounds, such as lime and hydrated phosphato of magnesia, in the
manner herein-after set forth.
For the charcoal I prefer to use charcoal made out of sewage deposit,
and for lime I prefer to use that which is prepared from pure limestone,
but it may be sometimes convenient to employ other descriptions of
charcoal and lime, and I sometimes also substitute magnesia or dolomotic
lime for lime.
I am aware that charcoal and the other substances mentioned havo
already been used for deodorizing night soil, and that alkaline earths
have been employed for the treatment of such matters and the decom-
position of nitrogenous substances (as, for instance, by one Gavin
Chapman, as described in the Specification of Letters Patent dated
twentieth October One thousand eight hundred and sixty-eight, No.
3203) as well as for precipitating liquid sewage, and that hydrated
phosphate of magnesia has been proposed as a means for recovering
ammonia from urinous and ammoniacal liquids, amongst others by myself,
under Letters Patent dated twenticth March One thousand eight hundred
and seventy-two, No. 849. I therefore make no claim for the use of
any of theso substances simply as such, nor do I claim for the use of
lime in conjunction with charcoal as purifying and deodorizing agents,
unless employed substantially in the special manner or manners herein-
after described.
My present Invention consists essentially of novel combinations in the
use of the above-mentioned substances, and of novel modes of applying
them to the treatment of night soil and urinous liquids which are
received into cesspools and other like receptacles, or after removal
therefrom.
In carrying out the process in cesspools and other receptacles of night
soil, the charcoal or other equivalent deodorant may be applied occa-
sionally through the fronts of the seats or otherwise, or it may be applied
by well known mechanical arrangements which discharge a certain
amount of the deodorant after each use of the privy or closet; but such
use of deodorant may be dispensed with, and the liquids be separated
from the solids by merely straining through a scrcon. The liquids which

page_text: -
drain off from the deodorants or the solid foeces are caused to traverse
filtering media consisting of layers of lime and of hydrated phosphate of
magnesia, and where great purity is required the liquids to be cleansed
are also passed through filters of charcoal. The lime in such filters will
retain the phosphoric acid present in the soluble form; and will also
decompose the urea of the urine, and at the same time produce ammonia,
which is then fixed by passing the urine through filters of hydrated
phosphate of magnesia in the form of ammoniacal phosphates. Any
phosphoric acid remaining in solution in the liquid (which passes
through the filter of phosphate of magnesia) is to be fixed by a second
filter of lime.
In cases in which the flow of urinous or ammoniacal liquid is rapid
(as, for instance, in cases in which the urine from several blocks of
houses is led to one point for treatment, and in public urinals) I employ
a series of such filters of lime and hydrated phosphate of magnesia.
One mode of applying my Invention to single cesspools or middens is
as follows:-I form in or adjoining the cesspool a chamber, into and
through which the liquids can flow off into the drains after passing
through filters of the before-mentioned substances, while the solid fœccs.
remain behind. The bottom of this chamber is provided with a catch
pit to allow of the settlement of any of the precipitated fertilizing
.matters which escape retention by the filters.
The direction of the filtration may be either upwards or downwards, or
may pass through the filters horizontally placed in scries, and so arranged
that the overflow of supernatant liquid from one filter may pass into the
next, and so on. Supposing upward filtration to be the plan to be followed
I commence by placing at the bottom of the chamber, or at some dis-
tance from it, as may be most convenient, a layer of charcoal (a); over
or adjoining this I place a layer of lime (6); over or adjoining the lime
filter a layer of hydrated phosphate of magnesia (c), and over or adjoining
the phosphate of magnesia a layer of lime (d); over or adjoining the
layer (d) another layer of charcoal (e)...
If the filters are arranged horizontally in series the clear supernatant
liquid from one tank or filter vessel flows through a channel to the bottom
of the next; but if they are arranged vertically one over the other I
prefer to separate the different layers by cocoa-nut matting, horse-hair
cloth, or other suitable material confined at the edges in frames of

page_text: galvanized iron. The galvanized iron frame should fit the chamber
pretty accurately, and can be supported on "sets-off" provided in its
construction. It is not however absolutely necessary to separate the
layers of filtering substance in this manner, although it will be found
convenient to do so when the phosphate of magnesia is to be recovered
in order that it may be used to deal with a fresh quantity of urine. The
urinous liquids, after passing through such a system of filters, will flow
into the drains in a comparatively pure and innoxious condition. The
quantities of the chemicals used will depend on the number of persons
using the cesspools, the frequency with which they aro emptied, and the
occupation of the people. If employed out of doors manifestly less urine
will find its way into the cesspools, as during the day it will be chiefly
voided in the fields. The proportion of phosphates and urea in the urine
is also much influenced by the character of the food of a population. It
will be necessary, therefore, that the time which should be allowed to:
clapse before the renewal of the lime and phosphate of magnesia and the
charcoal should be a matter for observation in each casc.
In an average case a cesspool for ten persons might require from five
pounds to ten pounds of lime per month if the urine is stale, and from
fifteen pounds to twenty pounds of lime per month if the urine is frosh, and
from seventy-five pounds to one hundred pounds of hydrated phosphate
of magnesia but the quantity of these chemicals required to effect the pur-
pose of my Invention will manifestly depend on the chemical composition
of the lime used as well as on the richness or otherwise of the excreta to
be dealt with, I therefore do not bind myself to the above proportions.
The charcoal or other deodorant of the solid fœeces is also manifestly
dependent on the character of the substance, and must be determined by
actual trial. When the cesspool is emptied the different layers may be
kept distinct, or if the free lime or magnesia which may happen to
remain is first neutralized the layers may all be mixed together. The
action of free alkaline earths tends as is well known to the expulsion
of ammonia from its combinations. In large towns it is more economical
to deal with the layer of ammoniacal phosphate of magnesia separately,
and (by well known methods) to expel its ammonia and re-employ the
recovered phosphate of magnesia for dealing with a fresh portion of a
ammoniacal liquid. In cases in which the cesspools are very largo the
liquids drain from them slowly, and they are only emptied at long
intervals. The omission of the filter of lime (d) is of less importance,

page_text: as much of the urine will have passed into decomposition spontaneously
before it reaches the layer of phosphate of magnesia, and in some cases
I provide a chamber of sufficient capacity to enable the urine to de-
compose before it reaches the filter of phosphate of magnesia, and then
dispense altogether with the lime filter (d). The filter of lime (6) will
extract the phosphoric acid of the soluble phosphates which pass through
as well as those which are dissolved out from the layer of phosphate of
magnesia (c).
It is of considerable advantage to make the lime filters in two or more
divisions, and in the first of these divisions (or that through which the
urine first passes) to employ lime which has been already partly
exhausted in the second and third divisions, and to replace what is
removed from the latter with fresh lime. The whole of the lime may
finally be fully exhausted in the first division of filter (d). By this means
the lime in the first division of filter (d) can be brought to a degree of
richness in phosphoric acid and nitrogen compounds, which will render it
a highly valuable commodity, and promote the decomposition of the
urine which passes through it.
In many cases in which the more perfect arrangements above
described are considered as inapplicable in consequence of the trifling
amount of urino to be dealt with, the filter of phosphate of magnesia
may be dispensed with. The contents of the second lime filter are
brought forward to the first as soon as they have become about two
thirds exhausted, and the second filter is refilled with fresh lime. The
second filter in this case breaks up the nitrogenous compounds and
allows the effluent to become charged with lime which preserves it in an
innoxious condition, and the carbonate of lime left in the filter is again
decomposed when removed to the first filter by the phosphoric acid in
the urine.
In dealing with excreta (when removed from the cesspools to a depôt
to be there treated) the use of the double lime filter previous to passing
the liquid through the phosphate of magnesia filter is specially advan-
tageous, and indeed this process (which I consider to be novel) is a very
useful preparation for the subsequent treatment of liquids, which are
rich in ammoniacal compounds by the process described by me under
Letters Patent, dated Twentieth March One thousand eight hundred
and soxantre tw
N
0.10

page_text: Although I consider the plan above described is best for dealing with
singlo cesspools it is not essential that a distinct chamber should be
made for the filters, nor that the materials should be applied as filters
for stirring in excessive quantitics of the chemicals as compared with
the amounts of the compounds to be removed from solution would
manifestly produce analogous results. In either case the liquid would
leave the last lime filter saturated with free limo which will produce
valuable effects in cleansing the sewers into which it ultimately finds its
way. The process of stirring is however only applicable when dealing
with urine at a depôt.
It will be sufficient in dealing with single cesspools to spread the
different layers of filtering material one over the other on the bottom of
the cesspool, and to protect each layer by cocoa-nut matting or canvas if
it be considered desirable to keep the chemicals separate. On the upper
layer is placed a perforated metallic or other screen to protect it from
the shovels of the workmen when removing the solid fœces.
In cases in
which the liquids cannot pass off into the sewers, a supplementary
cesspool may be attached to the chamber into which the liquids can be
drained after passing through the said filtering media. From this
cesspool the liquids (which after passing through the filtoring media will
be comparatively pure) can be pumped at intervals into the nearest sower
or watercourse.
When the system is followed of collecting the night soil and con-
veying it to a depôt to be there converted into a portable manure,
some modifications may with advantage be introduced into the mode of
procedure. If the collection from the cesspools and urinals is mado
without any special treatment with absorbents, I prefer that those
closets shall be used which provide for the separation of the liquids
from the solids. The solids I deodorize and dry by mixing with them
dried sewage deposit or other absorbent, such as charcoal or road
scrapings. In the subsequent treatment of the liquids (in lieu of at
once passing it through the filters of lime and hydrated phosphate of
magnesia and charcoal, as in the case of night soil and urinous liquids
in single cesspools, or proceeding as in the before mentioned Letters
Patent, dated Twentieth March One thousand eight hundred and
seventy-two, No. 849, which was specially applicable to very dilute
urinous solutions), I first remove the phosphoric acid of the soluble
phosphates by adding to the liquid so much milk of lime as is necessary

page_text: for its precipitation. Other matters of organic origin will also be
separated by the action of the lime. The precipitated phosphates and
organic matters thus obtained will form a valuable manure, and I find..
it advantageous to continue to stir the precipitate thus formed with the
liquid at intervals for a considerable time. I then proceed to the
filtration processes. I arrange the filters with spaces between them in
order that the chemicals used in them may be stirred up at intervals,
which may be done by mechanical means. I prefer to use a succession
of filters of phosphate of magnesia, say three or four instead of one deep
onc, so that I can gradually move back the materials (the lime and
phosphate of magnesia) as they gain in phosphoric acid and ammonia,
and by this means I secure the more complete action of the chemicals
employed, the most saturated being subjected to the strongest solutions.
If filtering fabrics are used to support the phosphate of magnesia
there is a tendency to the formation of crystals of ammoniacal magnesian
phosphato in their pores, and thus the proper filtration of the liquids is
impeded. It is of advantage therefore to wash these fabrics at intervals
with an acid solution.
By a special arrangement of privy drains the drainage.from several
houses may be conducted to one point before discharge into the main
sewers, and a filtering apparatus composed of two or more separate sets
of filters of the before mentioned substances may be there placed, and
be so arranged as to be readily visited for the purpose of stirring or
rearranging the filters as they become saturated, or for removing the
chemicals after they have done their duty. In this case and also in the
case of public urinals it is easy to arrange for periodical flushings
without interfering with the filters. To accomplish this it is merely
necessary to provide means for shutting the channel through the filters,
and opening another subsidiary channel to carry off the water, or to
make the filters themselves easily removeable. Similar arrangements
can be made for cases in which closets are used which are flushed at
intervals, or in which waterclosets are supplied with a limited and
regulated quantity of water. With a view also of keeping the urinals
sweet I pass a small quantity of milk of lime down the pipe for the
urine at intervals, as may be required.
In all those cases the charcoal may be mixed with the lime and phos-
phate of magnesia without departing from the nature of my Invention,
but I prefer to follow the plan above described, which gives compounds

page_text: having a higher value than when the charcoal is mixed with the lime
or other chemical agents. Lime and phosphate of magnesia may be
mixed together and used in one filter, but no advantage will be obtained
over the plan I have already described.
Having now described my Invention of "Improvements in the
Deodorization of Excreta, and in the Manufacture of Manures there-
from," and having explained the means whereby the same may be
carried into effect, I wish it to be understood that under the above in
part recited Letters Patent I claim as new, deodorizing excreta in
cesspools or other analagous receptacles, or after their removal there-
from, and the extraction of the fertilizing elements of such excreta by
the treatment of their liquid portions (when separated from the solid
matters) with lime or magnesia, or the two combined, and hydrated
phosphate of magnesia, in the manner and for the purposes hercin set
forth.
In witness whorcof, I, the said Henry Young Darracott Scott,
have hereunto set my hand and seal, the Ninth day of August,
in the year of our Lord One thousand eight hundred and seventy-
three