A METHOD OF DISINFECTING OR PURIFYING FOUL WATER
Year: 1885

page_text: I, HERBERT JOHN HADDAN, of 67, Strand, in the City of Westminster, Civil
Engineer, do hereby declare the nature of said invention for A METHOD OF
DISINFECTING OR PURIFYING FOUL WATER, a communication to me from abroad by
G. Langbein, Doctor, of Leipzig, in the kingdom of Saxony, to be as follows:-
All the methods hitherto employed for disinfecting purposes (especially with
reference to the sewage water in large towns) are more or less unsatisfactory,
particularly on the following grounds:
Either precipitates are formed (for instance when chloride of lime or salts of
iron, zinc, magnesia or alum, are used) which soon cause serious stoppages in the
conduits; or the lower organisms are not completely destroyed, but after lying
torpid for some time come to life again; or the water is rendered entirely useless
for manuring purposes by the reagents employed.
The method of disinfecting to which the present invention relates consists in the
employment of solutions of nitrous acid salts and dilute sulphuric or other acid, the
two solutions being conveyed separately to the substances to be disinfected in
which they are distributed as thoroughly as possible.
Such a method of disinfection obviates the defects already alluded to, and others
as well, since no precipitate is formed, moreover, the destruction of the lower
organisms is complete and immediate; and, lastly, the polluted water, after being
treated by this method, is much more valuable for manuring purposes, since the
nitrogen contained in the organic substances is converted into nitric acid and
ammoniacal compounds at the expense of the continually regenerated hypo-nitric
acid; to this is added all the nitrogen introduced in the form of nitrate of soda,
so that the water, not only reaches the fields in a pure state, but, owing to its
containing so much nitrogen, it is easily assimilated, and, therefore, very serviceable
for manuring purposes.

page_text: Owing to the regenerating action of the reagent, the consumption of the same
is much less than by other methods, as has been proved by many comparative
experiments.
This process does not require any costly apparatus, but only a few receivers
made of wood, some containing the very dilute sulphuric acid, and others the
solution of nitrite (nitrous acid salt).
The process of disinfection can eventually be carried out automatically, after
the proper quantities have been determined, by causing both solutions to flow
continuously into the canal or hose, but care must be taken to ensure their uniform
distribution.

page_text: A Method of Disinfecting or Purifying Foul Water.
I, HERBERT JOHN HADDAN, of 67 Strand, in the City of Westminster, Civil
Engineer, do hereby declare the nature of this invention, a communication to me
from abroad by G. Langbein, Doctor, of Leipzig, in the kingdom of Saxony, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
I. Method of action of this new disinfecting process.
Free nitrous acid, produced by mixing the solution of a nitrite; with diluted
sulphuric acid, acts energetically oxidizing on the organic constituents of sewage
water etc. and destroys the inferior organisms under the formation of nitrous
oxide gas, which, slightly soluble in water, oxidizes by contact with atmospheric
oxygen to hyponitric acid; the latter likewise acts energetically oxidizing, whereby
again nitrous oxide gas is produced, so that a rapid combustion of the organic
substances takes place under continuous regeneration of the disinfecting agent at
the expense of the oxygen of the atmospheric air. The sulphate of soda, formed by
the decomposition of the nitrite of soda by diluted sulphuric acid, is easily soluble
and quite innocuous.
IL Advantages of this new disinfecting process.
The disinfecting processes hitherto used, especially those of the canal or sewage
waters of great cities, give more or less insufficient results, principally for the
following reasons:
Either precipitates are produced, for instance by the application of chloride of
lime or the salts of iron, zinc, magnesia or alumn, which cause very soon trouble-
some obstructions of the canals, or the inferior organisms are not completely
destroyed, but recover again after a longer or shorter torpidity, or the waters loose
entirely their manuring value by the employed reagents.
The disinfection by a solution of nitrite of soda and very diluted sulphuric
acid comprises the following advantages.
1) No precipitates whatever are formed.
2) The inferior organisms are destroyed instantaneously and completely.
3) The nitrogen of the organic substances is transformed into nitric and
ammoniacal compounds at the expense of the hyponitric acid, continuously
regenerating itself. To this is added the whole nitrogen introduced in the shape
of nitrite of soda, so that therefore the waters not only come to the fields in a
disinfected state, but, by their considerable contents of nitrogen can be employed
as an excellent manure, in a directly convertible or assimilable shape.
4) Owing to the regenerating effect of-the disinfecting agent the consumption
of the same, in comparison with others, is very small, as repeatedly proved by
many comparative experiments. So, for instauce, for disinfecting one cubic metre
of foul water, an average amount of 50 grammes of nitrite was used with the
corresponding quantity of sulphuric acid.
5) Owing to its simplicity and cheapness, the above described process may
be advantageously applied in small towns, and by such a general application the

page_text: considerably diminished.
риба,
VORCE
III. Application of the new disinfecting process.
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A receptacle of wood contains an aqueous solution of the nitrite, preferably
nitrite of soda, while a second receptacle of wood contains a weak solution of acid,
preferably sulphuric acid:"-
If the strength of the solution of the nitrite of soda is such, that each 100 litres
of liquid contain 69 Kilos of nitrite of soda, and if the diluted sulphuric acid is
produced by pouring 5 Kilos of concentrated hydrate of sulphuric acid into
1000 litres of water, the disinfecting liquid may be obtained by mixing each part
(in volume) of the solution of nitrite of soda with 100 parts (in volume) of diluted
sulphuric acid, which mixture should then be immediately added to the liquid to
be disinfected.
The disinfection may also take place automatically after ascertaining the
required quantity of nitrous acid, by causing both liquids to run continuously
from pipes regulated by cocks into the sewer canal, sink etc., in which case, of
course, the two solutions must be uniformly mixed and distributed. According to
requirement, such disinfecting stations may be placed at the beginning of a canal
or several of them may be distributed over its course.
Having now particularly described and ascertained the nature of this Inven-
tion and in what manner the same is to be performed, I declare that, what
I claim is
"
The method or process of disinfecting, which consists in the application of
(a solution of) nitrite and of dilute sulphuric or other acid, the two solutions or
bodies being separately conducted to the material to be disinfected and finely
distributed in the latter.