Improvements relating to the Treatment of Sewage.
Year: 1899

page_text: …. PROVISIONAL SPECIFICATION.
Improvements relating to the Treatment of Sewage.
h
TE.. I, MARIE JEAN FERNAND THIRAULT, of Boulevard des Batignolles, Paris, in the
Republic of France, Barrister, do hereby declare the nature of this invention
to be as follows:-
1..
The questions of urban sanitation are, justly, those which most occupy public
authorities. The waste products of human life are not only bulky and incon-
venient but they also form the most usual vehicle of the germs of disease. The
products of animal digestion, from the double point of view of hygiene and
general economy, raise weighty questions for the municipal authorities with
respect to their initial reception, isolation, collection, removal, purification,
'industrial treatment and their use in agriculture.
1.1.
From the most established results of contemporary science, progressive hygienic
experts agree in declaring, from the point of view of public hygiene, if not from
that of rural economy, that the most perfect method of sanitation of towns con-
sists in diluting the human excreta, at the very moment of their production, with
the largest possible quantity of water and by the suppression of fixed cess-pools,
and the transference of the whole to the sewer, to carry off very rapidly from the
house and from the town, the flushing water charged with all the waste from
digestion...
*
35.
''
This system of discharging all into the sewer, with the addition of a field for
purifying the flushing water, is the one most advocated by hygienic experts.
But all towns are not, in a position to adopt this systém. Also 'other. hygienic
processes of collection tend to develope themselves every day and, in these different
processes, as well as in the most general case still, that of fixed or movable cess-
pools, the excreted matter which up till recent times, was only mixed with a
small quantity of water, is, by the application of the rules of cleanliness and
hygiene, more and more diluted in increasing masses of flushing or washing
water.
Its state of dilution reaches such a high degree that the processes existing
heretofore for withdrawing from the sewage the fertilising principles which it
contains, are less and less applicable.
Whatever be its method of collection, the sewage, mixed with more or less
water, should be disinfected to satisfy the requirements of general hygiene and
utilised in the manuring of land, to respond to the requirements of rural economy.

page_text: My invention has for its object a process capable of satisfying both the public
hygiene of towns and the interests of agriculture.
Amongst the methods of treating the sewage to disinfect the same, that which
consists in absorbing it by peat or turf, with a view to the production of a human
manure, is well known.
According to its origin, its composition, and degree of dryness, it is known
that peat or turf can absorb and disinfect many times its own weight of sewage
matter. This capacity of absorption which peat possesses for faecal matter has
recently received a somewhat large application in the employment of this product
as a litter for domestic animals.
But, in the treatment of sewage matter by peat, it has not heretofore been
known how to distinguish and separate the absorbing power of the peat for the
water contained in the sewage, on the one hand, from the absorbing and dis-
infecting power of the peat for the organic and mineral matter in suspension and
solution in the liquid sewage, on the other hand.
Moreover, the investigations and experiments which I have made, have led me to
discover that the peat has a limited power of absorption and, consequently, of
disinfection proper to each of the two constituent elements of the sewage, viz. :-
1stly. the water; 2ndly the organic and mineral substances in suspension and
solution in the water, and that if it absorbs several times its weight of liquid, it
can also absorb, that is to say, disinfect several times its weight of solid matter.
When the sewage is very much concentrated, its degree of humidity can be
such that the limited power of absorption of the peat for the water which it
contains, corresponds exactly to the limited power of disinfection of the peat
for the organic and mineral substances which they contain, cither in suspension
or in solution.
But in the most general case, the quantity of flushing or washing water is
such that, when the sewage matter is mixed with the peat, the limited power of
absorption of the latter for water is reached well before that of the absorption and
disinfection of the organic and mineral matter. In this case, by the simple
mixture, when the diluted sewage is absorbed by the peat, up to aqueous satura-
tion of the latter, the whole of the capacity of the peat for absorption and dis-
infection of the substances which are in suspension and solution in the liquid or
watery part of the sewage has not been exhausted.
From the industrial point of view, there results an incomplete utilisation of
the disinfecting power of the peat; from the agricultural point of view, there is
only obtained a human peat manure which is too watery and insufficiently en-
riched in fertilising principles.
Moreover, as much from the hygienic point of view as from that of agriculture,
in the industrial treatment of diluted sewage, that which it is important to study
is infinitely less the absorption of the water than the absorption and above all
the disinfection of the solid substances, for, from the agricultural point of view,
it is these last substances alone, that is to say, the fertilising materials, which
it is necessary to preserve; the water, on the contrary, must be got rid of.
The object which is to be attained, therefore, is to exhaust the extreme power
of absorption and of disinfection of the solid substances by the peat, whilst
separating it industrially from its power of absorbing water, in order to cause it
to absorb and, consequently to disinfect these solid substances to the maximum,
without causing it at the same time to absorb the water.
The new process which I have discovered and which permits this object to be
attained consists in causing the liquid or watery sewage to pass onto a bed or
layer of peat or turf, employing either simple or multiple filtration with or with
out pressure. In this operation of filtration, the absorbing and disinfecting
filtering material, that is to say the peat or turf, commences to become saturated
with moisture, at the same time as it absorbs a first part of organic and mineral
substances of the sewage, corresponding to the moisture of saturation of the peat
The liquid sewage continues to pass onto this filter of peat already saturated with

page_text: 4.
water and slightly enriched with organic and mineral substances, up to the
moment when the peat filter is also saturated with these latter materials. In
this second phase of the operation of filtration, the. peat previously saturated with
moisture, continues to become enriched with solid matter which it disinfects, but
allows the water of the sewage to pass, at the same time purifying it. When
there has been passed on to the peat-filter such a quantity of sewage that, after
the aqueous saturation, the saturation in organic and mineral substances is itself
attained, the operation is stopped.
The peat-filter, thus saturated is dried, either in the open air, or by artificial
drying with ventilation, and afterwards delivered for agricultural purposes as
concentrated organic manure.
The excess water of the sewage, which has passed through the filter and the
solid matter from which has been removed and disinfected, is itself purified.
The form, dimensions and the nature of the receptacles of the apparatus, as
well as the proportion, the thickness and the arrangement of the filtering
material, can be varied according to the origin and the composition of the peat
or turf, on the one hand, and the dilution of the sewage, on the other hand.
The operation of filtration above described is of necessity intermittent in a
single apparatus, by reason of the alternate charging and discharging of the absorb-
ing and disinfecting peat-filter. In a plant for the treatment of sewage by my
improved process, the operation will be rendered continuous by working with a
series of filters arranged according to the method termed, "by battery," or
du revolver," each of which filters is put into communication with the sewage
reservoir by means of a system of pipes or conduits and suitable cocks or valves.
In an arrangement of this kind, when a certain number of filters are stopped
for charging or discharging, there are always others in action performing both
absorbing and purifying filtration.
My process renders practical, from the triple point of view of public hygiene,
industrial economy and agriculture, the treatment of even the most dilute sewage
materials and ensures the complete utilisation for agriculture of the fertilising
organic and mineral substances contained in the sewage.
My process has thus for its result:-
1. From the hygienic point of view, the treatment industrially, in disinfecting
them, of all kinds of sewage, even the most dilute, and coming from all systems
of collection and thus freeing the towns therefrom; and the purification of the
liquid part of the sewage or effluent water from the sewer.
2. From the agricultural point of view, the utilisation of the filtering material
as a manure.
1000
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C., Agents for the Applicant.
Improvements relating to the Treatment of Sewage.
I, MARIE JEAN FERNAND THIRAULT, of Boulevard des Batignolles, Paris, in the
Republic of France, Barrister, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement:—
The questions of urban sanitation are, justly, those which most occupy public
authorities. The waste products of human life are not only bulky and incon-
venient, but they also form the most usual. vehicle for the germs of disease.. The
products of animal digestion from the double point of view of hygiene and

page_text: general economy, raise weighty questions for the municipal authorities with
respect, to their initial reception, isolation, collection, removal, purification,
industrial treatment and their use in agriculture,
From the most established results of contemporary science, progressive hygienic
experts agree in declaring, from the point of view of public hygiene, if not from
that of rural economy, that the most perfect method of sanitation of towns con-
sists in diluting the liuman excreta, at the very moment of their production, with
the largest possible quantity of water and by the suppression of fixed cess-pools,
and the transference of the whole to the sewer, to carry off very rapidly from the
house and from the town, the sewage water charged with all the waste from
digestion.
This system of discharging all into the sewer, with the addition of a field for
purifying the liquid part of the sewage, is the one most advocated by hygienic
experts.
But all towns are not in a position to adopt this system. Also other hygienic
processes of collection tend to develope themselves every day and, in these different
processes, as well as in the most general case still, that of fixed or movable cess-
pools, the excreted matter which up till recent times, was only mixed with a
small quantity of water, is, by the application of the rules of cleanliness and
hygiene, more and more diluted in increasing masses of flushing or washing
water.
Its state of dilution reaches such a high degree that the processes existing
heretofore for withdrawing from the sewage the fertilising principles which it
contains, are less and less applicable.
Whatever be its method of collection, the sewage, mixed with more or less
water, should be disinfected to satisfy the requirements of general hygiene and
utilised in the manuring of land, to respond to the requirements of rural economy.
My invention has for its object a process capable of satisfying both the public
hygiene of towns and the interests of agriculture.
Amongst the methods of treating the sewage to disinfect the same, that which
consists in absorbing it by peat or turf, with a view to the production of a human
manure, is well known.
According to its origin, its composition, and degree of dryness, it is known
that peat or turf can absorb and disinfect many times its own weight of sewage
matter. This capacity of absorption which peat possesses for faecal matter has
recently received a somewhat large application in the employment of this product
as a litter for domestic animals.
But, in the treatment of sewage matter by peat or turf, it has not heretofore been
known how to distinguish and separate the absorbing power of the peat or turf for
the water contained in the sewage, on the one hand, from the absorbing and dis-
infecting power of the peat for the organic and mineral matter in suspension and
solution in the sewage water, on the other hand.
Moreover, the investigations and experiments which I have made, have led me to
discover that the peat has a limited power of absorption and, consequently, of
disinfection proper to each of the two constituent elements of the sewage, viz. :-
1stly. the water; 2ndly the organic and mineral substances in suspension and
solution in the water, and that, if it absorbs several times its weight of liquid, it
can also absorb, that is to say, disinfect several times its weight of solid matter.
When the sewage is very much concentrated, its degree of humidity can be
such that the limited power of absorption of the peat or turf for the water which it
contains, corresponds exactly to the limited power of disinfection of the peat or
turf for the organic and mineral substances which it contains, either in suspen-
sion or in solution.
;
But in the most general case, the quantity of flushing or washing water is
such that, when the sewage matter is mixed with the peat, the limited power of
absorption of the latter for water is reached well before that of the absorption and
disinfection of the organic and mineral matter. In this case, by the simple

page_text: mixture, when the diluted sewage is absorbed by the peat, up to aqueous satura-
tion of the latter, the whole of the capacity of the peat for absorption and dis-
infection of the substances which are in suspension and solution in the liquid or
watery part of the sewage has not been exhausted.
From the industrial point of view, there results an incomplete utilisation of
the disinfecting power of the peat; from the agricultural point of view, there is
only obtained a human peat manure which is too watery and insufficiently. en-
riched in fertilising principles.
Moreover as much from the hygienic point of view as from that of agriculture,
in the industrial treatment of diluted sewage, that which it is important to study
is infinitely less the absorption of the water than the absorption and above all
the disinfection of the solid substances, for, from the agricultural point of view,
it is these last substances alone, that is to say, the fertilising materials, which
it is necessary to preserve; the water, on the contrary, must be got rid of.
The object which is to be attained, therefore, is to exhaust the extreme power
of absorption and of disinfection of the solid substances by the peat, whilst
separating it industrially from its power of absorbing water, in order to cause it
to absorb and, consequently, to disinfect these solid substances to the maximum,
without causing it at the same time to absorb the water.
The new process which I have discovered and which permits this object to be
attained consists in causing the liquid or watery sewage to pass onto a bed or
layer of peat or turf, employing either simple or multiple filtration with or with-
out pressure. In this operation of filtration, the absorbing and disinfecting
filtering material, that is to say, the peat or turf, commences to become saturated
with moisture, at the same time as it absorbs a first part of organic and mineral
substances of the sewage, corresponding to the moisture of saturation of the peat
or turf. The liquid sewage continues to pass onto this filter of peat or turf
already saturated with water and slightly enriched with organic and mineral
substances, up to the moment when the peat or turf filter is also saturated with
these latter materials: In this second phase of the operation of filtration, the peat or
turf previously-saturated with moisture, continues to become enriched with solid
matter which it disinfects, but allows the water of the sewage to pass, at the same
time purifying it. When there has been passed on to the peat- or turf filter such
a quantity of sewage, that, after the aqueous saturation, the saturation in organic
and mineral substances is itself attained, the operation is stopped.
The peat- or turf filter thus saturated, is dried, either in the open air, or by
artificial drying with ventilation, and afterwards delivered for agricultural pur
poses as concentrated organic manure.
The excess water of the sewage, which has passed through the filter and the
solid matter from which has been removed and disinfected, is itself purified.
The form, dimensions and the nature of the receptacles of the apparatus, as
well as the proportion, the thickness and the arrangement of the filtering
material, can be varied according to the origin and the composition of the peat
or turf, on the one hand, and the dilution of the sewage on the other hand.
The operation of filtration above described is of necessity intermittent in a
single apparatus, by reason of the alternate charging and discharging of the absorb-
ing and disinfecting peat- or turf filter. In a plant for the treatment of sewage
by this process, the operation will be rendered continuous by working with a
series of filters arranged according to the-method-termed "by battery," or "du
revolver; each. of which filters is put into communication with the sewage reser-
voir by means of a system of pipes or conduits and cocks or valves connected there-
with. In an arrangement of this kind, when a certain number of filters are
stopped for charging or discharging, there are always others in action performing
both absorbing and purifying filtration.
To obtain a good result, it is not necessary that the peat or turf should have
to retain more than its own weight of organic matter contained in the sewage
liquid.

page_text: The filter is prepared in the following manner:-The filter bed should be
very thick and be arranged in very high receivers or columns.
At the bottom, there is a very thick felt or layer of peat, as much as possible
in a single piece, so as to prevent the passage of the organic matter and to retain
the fertilizing principles, such as ammoniacal nitrogen, in solution in the liquids
to be filtered. .
At the top of the filter, there are pieces of peat in order to allow the organic
matter to pass into the empty spaces between the pieces and to prevent the forma-
tion, at the top of the filter, of a greasy layer of organic matter which would form
an obstacle to the filtration.
In the middle of the filter there is pulverized peat.
Finally, the filtering material should be held between the bottom of the
receiver and a grid at the top in such a manner that it is well supported and the
liquid can pass over the whole of the filtering material.
In order to obtain a perfect result, it is necessary to pass the liquids succes-
sively over several filters, e.g., three, four, or even more.
With this process, a new and certain result is obtained.
My process renders practical, from the triple point of view of public hygiene,
industrial economy and agriculture, the treatment of even the most dilute sewage
materials and ensures the complete utilisation for agriculture of the fertilizing
and mineral substances contained in the sewage.
My process has thus for its result.
1. From the hygienic point of view, the treatment industrially, in disinfecting
them, of all kinds of sewage, even the most dilute, and coming from all systems
of collection and thus freeing the towns therefrom; and the purification of the
liquid part of the sewage or effluent from the sewer.
2. From the agricultural point of view, the utilisation of the filtering material
as a manure.
Having now particularly described and ascertained the nature of my said
invention and in what mai ner the same is to be performed, I declare that what
I claim is:
-
1. In the treatment of sewage by peat or turf, a process wherein the absorbing
power of the peat or turf for liquids and especially for the liquid part of sewage
or effluent from sewers, is separated from its power of absorption and disinfection
of the oragnic and mineral substances in suspension and in solution in the liquids,
substantially as, and for the purposes herein before described.
2. The improved process for treating sewage consisting in passing the sewage
or effluent on to a bed or layer or beds or layers of peat or turf by simple or
multiple filtration with or without pressure, so as to saturate with the fertilising
principles contained in the sewage the filtering material which thus becomes an
inodorous and concentrated manure suitable for agricultural purposes, substan-
tially as hereinbefore described, and for the purposes specified.
* Dated this 6th day of December 1899.
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C., Agents for the Applicant.