IMPROVEMENTS IN THE PURIFICATION OF SEWAGE WATERS AND THE LIKE AND THE RECOVERY OF VALUABLE PRODUCTS THERERDOY”
Year: 1883

page_text: LETTERS PATENT to Johannes Bock, Doctor of Philosophy of Zuckerfabrik,
Puschkau near Königszelt, Silesia, German Empire for an Invention of
"IMPROVEMENTS IN THE PURIFICATION OF SEWAGE WATERS AND THE LIKE
AND THE RECOVERY OF VALUABLE PRODUCTS THERERDOY”
PROVISIONAL SPECIFICATION left by the said Johannes Bock at the Office
of the Commissioners of Patents on the 30th June 1883.
JOHANNES BOCK Doctor of Philosophy of Zuckerfabrik Pusckkau [Puschkau]
near Königszett [Königszelt] Silesia, German Empire "IMPROVEMENTS IN THE
PURIFICATION OF SEWAGE WATERS AND THE LIKE, AND THE RECOVERY OF
VALUABLE PRODUCTS THEREFROM
"
This process for chemically purifying waste waters of all kinds, drainage and
sewage waters and the like, is based mainly upon the separation of the solid
component parts from the clear solutions and separate treatment of both. Hereby
it is rendered possible to separate from the clear solution, and to use for manuring
purposes, all the suspended particles which the sewage waters &c contain, including
all microscopic organisms, spores, as well as a portion of noxious dissolved matters,
the sulphuret of hydrogen and other gases. The clear solution is then subjected
to a chemical treatment which has for its main result to destroy the organic
constituents still contained in the solution and also the precipitation of the
combinations resulting from the first operation so that no further objection
obtains to allowing these liquids to flow into public watercourses.
To enable the said solid substances &c to be completely separated from the liquid
ones, I add to the waste waters to be treated fibrous substances together with salts
of iron and magnesia, and only after this 1 effect precipitation by milk of lime.
By the addition of fibrous material a dense precipitate is produced, whilst when
only chemically active matters are added, a slight precipitate is produced which
settles but slowly and renders separation more difficult
The quantity of substances to be added of course varies according to the nature
of the waste waters. In general it will suffice to add on an average per cubic
meter of the liquid, 250 grammes of wood pulp or papor-fibre, 140 grammes of

page_text: chloride of iron, 100 grammes of concentrated lye of manganate of alkali, and
1500 grammes of caustic lime in the form of milk of lime." If the waste waters
already contain suspended fibres, then the addition of fibres will be proportionately
decreased
After the precipitate has settled, the supernatant liquid is run off and filtered by
a "Purvez trough filter" so as to remove the last traces of suspended particles.
The clear liquor thus obtained is then subjected to further chemical treatment
whilst the precipitate obtained in the first operation is further condensed in
filtering or other suitable presses, in centrifugal apparatus &c so as to enable the
same to be used for manure for which purpose it is particularly adapted both by its
chemical and physical constitution.
In this manner all the phosphoric acid as well as the nitrogen contained in the
waters are obtained in the solid transportable manure and in a concentrated
form whilst these matters heretofore were distributed in a large volume.
I expressly observe that I do not claim either the use of milk of lime, or of the
other chemicals in themselves as the separate employment of all these materials for
clarifying waste waters has already frequently been proposed, I however consider
as new the addition of the fibrous material (which in the case under consideration,
by reason of its small quantity, does not in any way act as a filtrant) in combination
with the above named substances as it is only by this that the matters contained
in the waste waters are precipitated in such a form and so completely that an
efficient filtering and clarification become possible.
The clarified solution, is now treated with an oxidising agent so as to destroy
certain matters whose elimination from the original waste water would have been
impossible. The selection of these oxidising agents depends of the nature of the
water, in general however 1 prierably employ manganate of alkali in the
proportion of about 100 grammes pr Cubic meter of the water to be purified.
The solution thus trented still contains calcium compounds in solution derived.
from the first treatment and these, by their chemical reaction might become
obnoxious in the water that flows off. The solution is therefore still further
.subjected to treatment with sulfurous acid which is carried to such extent that,
besides the sulfite of lime a very small proportion of bisulfite of lime is produced
which to a very high degree possesses the property of keeping the water entirely
unaltered for a long while..
After the treatment with sulfurous acid the water may either be allowed to
settle or be freed from the sediment by a "Purvez" filter and be now run off as a
clear nure liquid.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Johannes Bock in the Great Seal Patent Office on the
29th December 1883.
JOHANNES BOCK Doctor of Philosophy of Zuckerfabrik Puschkau near
Königszelt Silesia German Empire. "IMPROVEMENTS IN THE PURIFICATION OF
SEWAGE WATERS AND THE LIKE AND THE RECOVERY OF VALUABLE PRODUCTS
THEREFROM
22
This process of chemically purifying waste waters of all kinds, drainage and
sewage waters and the like, is based mainly upon the separation of the solid com-
ponent parts from the clear solutions and separate treatment of both. Hereby it
is rendered possible to separate from the clear solution, and to use for manuring
purposes, all the suspended particles which the sewage waters etcetera contain,
including all microscopical organisms, spores, as well as a portion of noxious dis-
solved matters, the sulphuret of hydrogen and other gases. The clear solution is
then subjected to a chemical treatment which has for its main result to destroy the
organic constituents still contained in the solution and also the precipitation of the
combinations resulting from the first operation so that no further objection obtains
to allowing these liquids to flow into public watercourses.
To enable the said solid substances etcetera to be completely separated from the
liquid ones, I add to the waste waters to be treated fibrous substances together
with salt of iron and magnesia, and only after this I effect precipitation by milk of
lime. By the addition of fibrous material a dense precipitate is produced, whilst
when only chemically active matters are added, a slight precipitato is produced
which settles but slowly and renders separation more difficult.
The quantity of substances to be added of course varies according to the nature
of the waste waters.
In general it will suffice to add on an average, per cubic-meter of the liquid,
250 grammes of wood pulp or paper-fibre, 140 grammes of chloride of iron,
100 grammes of concentrated solution of chloride of magnesium and 1500 grainmes
of caustic lime in the form of milk of lime. If the waste waters already contain
suspended fibres, then the addition of fibres will bo proportionally decreased.
Instead of the salts of iron oxides of iron may be used in combination with
fibrous material, salts of magnesin and milk of lime. Amongst other combinations
artificially precipitated hydrated peroxide of iron has proved especially advantageous
in lieu of the chloride of iron 200-500 grammes of this compound being enough
for a cubic meter of water. To the hydrated peroxide of iron a small quantity
(say 5 to 10%) of soda or other alkali may be added. Instead of fibrous inaterial
may use fibriferous mud for clarifying.
After the precipitate has settled, the supernatant liquid is run off and filtered.
by "Puvrez trough filter" so as to remove the last traces of suspended particles..
The clear liquor thus obtained is then subjected to further chemical treatment,
whilst the precipitate obtained in the first operation may be used for clarifying
fresh quantities of waste waters and then it will, as a rule, not be required to add
more than about ½, of the fibrous compounds, the magnesia salts and lime used for
the first precipitation.
In practice this process may also be carried on by drawing off the clarified liquid
and allowing fresh waste water to run onto the precipitated mud; when the
chemicals have been added the whole is repeatedly agitated and allowed to settle.
After the second precipitation part of the mud may be removed, the rest being
used for clarifying fresh quantities of waste water in the manner above set forth,
and so on.
In this manner each mud particle can repeatedly be used for clarifying and by
operating in this manner not only is a considerable saving effected in precipitants

page_text: 1.ut moreover space and time are also economised as precipitation by mud that has
already been used is exceedingly rapid and perfect. The solid precipitates are
further condensed in filtering, or other suitable presses, in centrifugal apparatus
etcetera so as to enable the same to be used for manure for which purpose they aro
particularly adapted both by their chemical and physical constitution.
In this manner all the phosphoric acid as well as the nitrogen contained in the
waters are obtained in the solid, transportablo manure, and in a concentrated form
whilst these matters heretofore were distributed in a large volume.
I expressly observe that I do not claim either the use of milk of lime, or of
the other chemicals in themselves, as the separate employment of all these materials
for clarifying waste waters has already frequently been proposed, I however consider
as new the addition of the fibrous materials or of the fibriferous mud (the fibres
in the case under consideration, by reason of their small quantity do not in any
way act as a filtrant) in combination with the above named substances as it is only
by this that the matters contained in the waters are precipitated in such a form
and so completely, that an efficient filtering and clarification become possible.
The clarified solution is now treated with an oxidising agent so as to destroy
certain matters whose elimination from the original waste water would have been
impossible. The selection of these oxidising agents depends upon the nature of the
water, in general however I preferably employ manganate of alkali in the
proportion of about 100 grammes per cubic meter of the water to be purified.
The solution thus treated now still contains calcium compounds in solution,
derived from the first treatment, and these by their chemical reaction might
become obnoxious in the water that flows off. The solution is therefore still further
subjected to treatment with sulphurous acid which is carried to such extent that,
besides the sulphide of limo a very small proportion of bisulphite of lime is
produced which to a very high degree possesses the property of keeping the water
entirely unaltered for a long while.
After the treatment with sulphurous acid the water may either be allowed to
settle or be freed from the sediment by a Purvez' filter and be now run off as a
clear pure liquid.
Having now described the nature of my said invention and the manner of
performing the same, I wish it to be, understood that I claim..
First The chemical purification of waste waters of all kinds by the addition of
fibrous material or of fibriferous mud in combination with iron-compounds and
inagnesia salts besides milk of lime substantially in the proportions set forth, for
the purpose of precipitating the fouling particles and ferinenting seeds in a com-
pact form and directly to render the separated substances suitable for munuring
purposes..
Second-In the method for chemically purifying sewage or waste waters and
the like, the repeated use of the above specified clarifying substances in such
manner that the mud from one precipitation is used for a second precipitation, this
proceeding being repeated, with or without the addition. of fresh precipitants as
may be desirable.
Third The introduction of sulphurous acid into the clear solution so as to
eliminate the lime in solution and to form antiseptic and disinfectant bisulphite of
line.
In witness whereof 1 the said Johannes Bock have hereunto set iny hand and
seal this twentieth day of December in the year of our Lord One thousand eight
hundred and eighty three..