IMPROVEMENTS IN TREATING SEWAGE AND IN DISPOSING OF THE SLUDGE BY MANUFACTURING ARTIFICIAL MANURE FROM THE SAME
Year: 1884

page_text: I FRITZ HILLE of Chiswick in the County of Middlesex Engineer do hereby
declare the nature of my invention for "IMPROVEMENTS IN TREATING SEWAGE
AND IN DISPOSING OF THE SLUDGE BY MANUFACTURING ARTIFICIAL MANURE FROM
THE SAME" to be as follows:-
This Invention has for its object improvements in treating sewage and in making
artificial manure from the sludge.
For the purification of sewage to be generally carried out the method adopted
must not only be simple but also cheap and practically applicable under different
conditions and circumstances. The treatment of the sewage must be efficient so as
to allow the effluent produced to be discharged into river or sea without causing
injury either to animal or to vegetable life. A great difficulty in the disposing of
sewage is the sludge; the greater the quantity and the bulk of sludge produced
the greater becomes the difficulty therefore the treatment of sewage ought to be
manipulated in such a way as to produce a minimum quantity of sludge; to obtain
this result the chemical treatment must be of such a nature that no bulky or heavy
substances are employed as ingredients of the chemical compound used. With
this view I treat sewage in the way described underneath. Before the sewage
enters the precipitating tanks after all the heavy floating matter contained in the
sewage has been intercepted by means of suitably und well placed screens and
when flowing into the pumping well from which it is lifted I introduce into the
sewage a solution composed of either chloride of magnesium or chloride of calcium
or of other chlorides and per chloride of iron or a solution of alum, or I introduce
into the sewage according to circumstances i,e, quality and character of the sewage
a solution of either of the above mentioned chemicals singly without combining
two of them. This or these solutions are added to the sewage in the pumping well
or as the locality and circumstances may make it convenient and practicable and
sewage and chemicals mixed together are lifted into a channel leading to the deposit
tanks so that before reaching the tanks they become thoroughly mixed together.
In cases where lifting of the sewage is not required and where the raw and crude
sewage reaches the outfall works by gravitation, arrangements for supplying the
chemicals for treating the sewage must be adopted according to the locality and
according to circumstances so as to ensure the greatest possible effect of the chemicals

page_text: used. Now, arrangements have to be made that at the point where or before the
sewage mixed with the solution or solutions above described enters the deposit
tanks line water in sufficient quantity is added. The addition of this lime water
produces a bulky precipitate which quickly subsides carrying down with it all the
suspended matters in the sewage and leaving a clear and inodorous supernatent
water. The subsidence taking place is very rapid. I use instead of hydrated lime
for the special purpose of not introducing the bulk and the weight of the lime
into the sewage. Besides I do this also for the purpose of considerably cheapening
the treatment of the sewage-inasmuch as the residue of lime may be used and sold
for various purposes. The line water I prepare in the usual way at or near the
sewage works where and when it may be required. Where or in cases when
particularly strong or very offensive sewage has to be dealt with the addition of a
small quantity of diluted carbolic acid in proportion to the other ingredients used
may advantageously be made and deodorization will in such cases be greatly
facilitated.
By the means described clarification and deodorization of the sewage will bo
efficiently and cheaply secured.
To overcome the difficulty of disposing readily of the sludge not only in an
inexpensive but in a profitable way I proceed as follows: As stated the larger the
quantity of sludge to be disposed of the greater the difficulty and it is therefore
desirable to reduce the quantity of sludge to a minimum; this can be done by
using as described for treatment of the sewage materials and chemicals not bulky
or of heavy weight-and, by avoiding accumulation of sludge. The best way of
obtaining this end is ly cleaning out the deposit tanks as frequently as circumstances
will permit. By preference I should not use any one precipitating tank for a longer
period than from 3 to 6 days in maximo and the tanks should be so designed and
arranged that a frequent cleaning out and an easy removal of the sludge may at
any time be effected. A great advantage in successfully treating sewage chemically
is obtained by providing ample tank room and I should by preference have tanks
capable of holding the total of two days ordinary dry weather flow; the tanks
should also provide facilities for drawing off the effluent water and for removing
the sludge every day if wanted. If it can be done the sludge produced during
24 hours should be disposed of every day by having the moisture it contains (some
90% of water) removed by suitable presses; if this cannot be done so frequently
the sludge should be stored in sludge pits where a great part of the moisture may
be removed by means of suitable drainage of the sludge pits. When the sludge
has been pressed into cakes a good artificial manure may be obtained by fortifying
the sludge after it has been crushed into a rough powder by means of a mortar mill
or other available contrivance, with Kainite in the proportion of mixing four tons
of pulverized sludge with one ton of Kainite or in different proportions as
circumstances may require. Another method of giving additional value to the
Eludge in using it as carrier or basis for artificial manure is by adding the residue
or part of the residue of lime which has previously been used for making the lime
water (after treating the lime residue in a suitable way with phosphoric acid) in the
shape of phosphates of lime or by adding other fortifying ingredients of different
descriptions as occasion may require.
Dated thin 11th day of Janvar 1984

page_text: I, FRITZ HILLE of Chiswick in the County of Middlesex-Engineer do hereby
declare the nature of my Invention for "IMPROVEMENTS IN TREATING SEWAGE
AND IN DISPOSING OF THE SLUDGE BY MANUFACTURING ARTIFICIAL MANURE
FROM THE SAME "and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:―
This Invention has for its object improvements in treating sewage and in making
artificial manure from the sludge. To carry out generally purification of sewage
the method must not only be simple but also cheap and easily and practically
applicable under different conditions and circumstances. A great difficulty arises
in the disposal of sewage through the sludge produced by chemical treatment and
the greater the quantity and the bulk of the sludge produced the greater becomes
this difficulty, therefore sewage when chemically treated ought to be treated in
such a way as to produce a minimum quantity of sludge of the greatest possiblo
value in quality as regards fertilizing constituents. To obtain this result the
chemicals used ought not to be of an excessively bulky or heavy nature and they
should at the same time be substances producing fertilizing and useful components
of the sludge. Besides, the chemicals used must produce an effluent water
sufficiently purified to allow it being discharged into a river or sea without causing
injury either to animal or to vegetable life.
To obtain these results I treat sewage in the way described underneath; before
the sewage enters the precipitating tanks after all heavy floating matter contained
in the sewage has been intercepted and removed by means of suitably and well
placed screens, and when flowing into the pumping well from which it is lifted,
I introduce into the sewage a solution composed of either chloride of of magnesium
or chloride of calcium or chloroxide of calcium or oxychloride of calcium or of
other chlorides or of perchloride of iron or a solution of alum; or I introduce into
the sewage according to circumstances i.e. according to quality and character of the
sewage a solution composed of a combination of some of the above named
chemicals. Such solution is added to the sowage in the pumping well or as the
locality and circumstances may make it convenient and practicable. Sewage and
dissolved chemicals mixed together are lifted into a channel leading to the deposit
tanks so that before reaching the tanks they become thoroughly mixed In cases
where lifting the sewage is not required and where the raw and crude sewage
reaches the outfall works and tanks by gravitation arrangements for supplying the
chemicals used for treating the sewage inust be adopted according to locality and
circumstances so as to ensure the greatest possible effect of the chemicals added.
Now, arrangements have to be made that at the point where or before the
sewage mixed with the solution of salts above described enters the deposit tanks,
lime water in sufficient quantity is added. The addition of this lime water
produces a bulky precipitate which quickly subsides carrying down with it all the
suspended matters in the sewage and leaving a clear and inodorous supernatent
water. The subsidence taking place is very quick and rapid. I uso lime water as
a rule instead of hydrated lime for the special purpose of not introducing the bulk
and the weight of the lime itself into the sewage, and also for the purpose of
considerably cheapening the treatment of the sewage in as much as the residue of
lime may be sold and used for various objects. This lime water I prepare in tho
usual way at or near the sewage works where, and as it may be required. In
exceptional cases diluted hydrated lime may be used instead of lime water, Where,

page_text: or in cases when particularly strong and offensive sewage has to be dealt with or,
where it may be desirable, an addition of a small quantity of diluted carbolic acid
in proportion to the other ingredients used may advantageously be made and
deodorization of effluent water and of the sludge will in such cases be greatly
facilitated.
By the means and the chemicals described clarification and deodorization of the
sewage will be efficiently and cheaply secured.
There may be cases where it is desirable (with the view of purifying the air in
the Sewers and destroying to a great extent sewer gas or preventing the formation
of it) to add the dissolved chemical Salts before the sewage reaches the outfall works;
in such cases any of the above named Salts either crushed into Powder or dissolved
in water, with a proportionate quantity of diluted carbolic acid or diluted
carbolated creosote may be introduced to the sewage at such points in the town
sewers where it can be conveniently done, and Lime water or hydrated Lime is
added just before the sewage renches the outfall works where rapid precipitation
takes place. By introducing the Salts in solution with carbolic acid or with
carholated creosote, or by introducing carbolated creosote or carbolic acid without
any of the Salts named, in the Sewers no sewage deposit will be precipitated in
the sewers but the chemicals added will be thoroughly mixed with the sewage and
the introduction of the deodorant will greatly contribute to the purification of the
air in the Sewers, and that is a most material advantage gained as it reduces to a
great extent the formation of sewer gas.
To overcome the difficulty of disposing readily of the sludge, not only in an
inexpensive but in a profitable way I proceed as follows:-As stated, the larger
the quantity of sludge to be disposed of the greater the difliculty; it is therefore
desirable to reduce the quantity produced as much as possible, by using as described,
for treatment of the sewage materials and chemicals not bulky or heavy in weight
and by avoiding accumulation of sludge. The best way of obtaining this end is
by cleaning out the deposit from the deposit tanks as frequently as circunstances
will permit.
By preference I should not use any one precipitating tank for a longer period
than from 3 to 5 days at the utmost, and the tanks should be designed and
arranged that a frequent cleaning out and an easy removal of the sludge may at
any time be effected. A great advantage in successfully treating sewage chemically
is obtained by providing ample tank room and I should by preference provide
storage room by means of a Reservoir and of Deposit Tanks. A reservoir will to
a great extent prevent pumping sewage during night time and on Sundays-This
will facilitate a regular treatment of the sewage at all times.
Reservoir and Deposit Tanks should be capable of holding the total of two days
ordinary dry weather flow; the construction and arrangement of the tanks should
also provide facilities for drawing off the effluent water and for removing the
sludge every day, if wanted. If it can be done the sludge produced during
24 hours should be disposed of every day by having the moisture it contains (some
90% of water) removed by suitable presses; if it cannot be done so frequently
then the sludge should be stored in sludge pits where a great part of the moisture
inay be removed by means of suitable drainage and arrangement of the sludire pits.
When the moisture has been removed from the sludge and it has been pressed into
cakes a good artificial inanure may be obtained by fortifying the sludge, after or
whilst being crushed into a rough powder by means of a common mortar mill or
by any other available contrivance, with Kainite in the proportion of mixing four
tons of pulverised sludge with one ton of Kainite, or in different proportions as
circumstances may require. Another advantageous manner of giving additional
value to the sludge in using it as a carrier or base for artificial manure consists in
adding to it the residue or part of the residue of the lime after the lime has been
used for making the line water (after treating the lime residue in a suitable way
with phosphoric acid) in the shape of phosphate of lime or by adding other
fertilizing ingredients of different descriptions as occasion may requiro,
G

page_text: Another method of disposing in an easy way of the sludge is to be found where
suflicient land is available for the purpose-by digging the sludge into the earth
and to use the land for crops by rotation. Splendid crops can be obtained from
land so manured by sludge; and if the sludge can be delivered on to the land by
means of pumping a considerable saving of labour will be effected. The best way
of absorbing the sludge and amalgamating it with the natural soil, will be, to uso
square beds about 12 feet long with an embankment of earth around about one
foot in height. When these beds have been filled with sludge, after a time the
moisture contained in the sludge disappears and gradually in course of time the
sludge turns into a kind of mould similar to garden soil, and constitutes a valuable
soil rich and fertilizing.
The effluent water where desirable or necessary for further purification should be
filtered either through artificial filters formed by furnace refuse, burnt ballast or
some other cheap and easily accessible filtering material, or, where it can be done
and where land can be obtained for filtering purposes through land; such land
should be laid out in filtering beds each of one acre in extent (or of such size as
the locality may permit) and these ought to be well under drained. The filtering
beds should be used in rotation so that the filtering material or the land may have
the benefit of the purifying influence of the air and become well aëratol; it is
also desirable that the earth should be turned over or ploughed once a year or
oftener if required. Where potable water is taken from a watercourse for
domestic or for dietetic purposes the effluent water produced by chemical treatment
should always be well filtered before being allowed to pass into a river-The
filtering beds I by preference use are constructed after the soil has been thoroughly
turned over to a depth of at least 18 inches-The filtering beds should have an
embankment around each partition to the height of about 2 feet 6 inches (more or
less) so, that filling these filtering areas, the purified sewage has time to percolate,
not too rapidly, but so that the greatest effect is obtained from the filtering
medium.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is
First The treatment of sewage by means of chloride of magnesium or chloride
of calcium or chloroxide of calcium or oxychloride of calcium or perchloride of
iron or other chlorides, or alum followed by lime water or otherwise substantially
as described and with or without the introduction of "Carbolated Creosote" as a
deodorizer; which treatment has for its object the exclusion of all bulky matter
and of materials heavy in weight, so as not to introduce or to add any materials
to the sewage which would increase the quantity of sludge, producing at the
same time by using the chemicals described an effluent water sufficiently purified
to be discharged into river or sea.
Second. The disposal of the sewage deposit in an easy and profitable way as
artificial manure by compounding the same with Kainite or with lime residue
treated with phosphoric acid substantially in the manner described.
CARPMAEL & Co.,
Agents for the Applicant,