Improvements in the Treatment of Sewage and in Obtaining certain useful Products thereby.
Year: 1891

page_text: Date of Application, 20th June, 1891
Complete Specification Left, 20th Apr., 1892-Accepted, 28th May,
1892
ROYIDINA I
Improvements in the Treatment of Sewage and in Obtaining certain
useful Products thereby.
We, ALFRED HOSSACK, of No. 39, Brook Street, in the Parish of St. George's,
Hanover Square, in the County of Middlesex, Artist, and HENRY CLAY BULL, of
No. 31, Poultry, in the City of London, Engineer, do hereby declare the nature of
this invention to be as follows
This invention relates to improvements in the treatment of sewage by means of
which, certain constituents thereof are utilised and a comparatively pure and
innocuous liquid obtained.
The sewage is, at the outfalls, mixed by a suitable mixing apparatus, with lime
in such quantity as will more than saturate the water contained therein; at the
same time, a quantity of finely pulverised slack coal, or peat charcoal, or a mixture
of pulverised slack coal and peat charcoal is mixed with the sewage this operation
is carried on continuously, the sewage and materials mixed therewith flowing from
the mixing apparatus into settling tanks, and, when it has settled, the liquid is
withdrawn and is passed through a second mixing apparatus.
The sludge, deposited in the before mentioned settling tank, will be found
suitable for the manufacture of illuminating gas, and for that purpose, it may be
moulded into brickets and dried. During the process of manufacturing gas from
such brickets, the whole, or nearly so, of the ammonia contained in the mixture
introduced into the settling tank and which has been deposited with the sludge, will
be recovered in the usual manner.
After the manufacture of the illuminating gas, as lastly referred to, the residual
carbon will be found suitable for conversion into water gas, the residual oils,
recovered during the production of the illuminating gas, being employed to carburet
the same.
The ash, produced in making water gas by the above means, will contain the
mineral manures of the sewage treated.
The liquid, by means of the said second mixing apparatus is brought into
intimate contact with river mud and carbonic acid gas; it is then discharged into a
second settling tank in which the carbonate of lime formed in the last mixing
operation, and the river mud will be deposited as a sludge, which will be found
suitable for the manufacture of Portland cement.
The liquid from the second precipitation is passed through filters in which the
filtering inedium is composed of peat charcoal, by preference obtained from peat
litter from stables.
The exhausted peat charcoal from the filters will be found suitable for mixing,
either alone or combined with coal, as hereinbefore stated, with the sewage before it
enters the first precipitating tank.
The apparatus required for carrying on the operations herein before referred to,
will consist mainly of the mixing machines, the necessary pumps, filters, and tanks,
and the same may be of any suitable and known nature.
Dated this 20th dar of June 1891.
VAUGHAN & SON,
Agents for the Applicants.

page_text: COMPLETE SPECIFICATION.
Improvements in the Treatment of Sewage and in Obtaining certain
useful Products thereby.
We, ALFRED HOSSACK, of No. 39, Brook Strect, in the Parish of St. George's,
Hanover Square, in the County of Middlesex, Artist, and HENRY CLAY BULL, of
No. 31, Poultry, in the City of London, Engineer, 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 :-
Our said invention relates to improvements in the treatment of sewage by means
of which the solid constituents thereof are utilised and a comparatively pure and
innocuous liquid discharged.
In carrying this invention into effect, the town sewage is intercepted at the
outfalls, and conducted into a suitable mixing apparatus and is there combined with
lime, by preference in the form of milk of lime, in such quantity as will more than
saturate the water contained in the sewage, and, at the same time, a quantity of
finely pulverized slack coal is mixed with the mass for the purpose of expediting the
settlement or precipitation of the sludge. The quantity of pulverised coal
employed may be varied according to the proportion of solid or organic matter
contained in the sewage, the larger the quantity the more expeditiously will the
precipitation be effected. The presence of the coal renders the sludge more
suitable for the production of illuminating gas.
The mass, consisting of sewage mixed with the milk of lime and pulverized slack
coal, is then run into shallow settling tanks where it is allowed to remain until the
required amount of precipitation or settlement has taken place; the liquid is then
drawn or allowed to run off and treated separately as hereinafter described, after
which the sludge is removed into, and distributed amongst, a series of deep settling
tanks where it is allowed to remain uncil thoroughly settled, when any liquid, which
has become separated from the sludge, is withdrawn from these deep tanks, and has
added thereto a quantity of lime, by preference in the form of milk of lime, and is
reconducted into the shallow settling tanks to be employed in connection with a
fresh quantity of sewage.
The sludge deposited in the deep settling tanks is, after the withdrawal of the
liquid, made into brickets, or blocks of any convenient form and dried, and these
brickets or blocks will be found suitable for the manufacture of illuminating gas by
the ordinary process of distillation, during which process, the whole, or nearly the
whole, of the nitrogen contained in the sludge will be recovered as ammonia in the
usual manner.
After employing the sludge in the manufacture of illuminating gas, as lastly
hereinbefore described, the resulting carbon will be found suitable for conversion
into water gas and the residual tar and other products, such as hydrocarbon oils
distilled out during the production of the illuminating gas may be employed in any
known manner for the purpose of carburetting the water gas.
The ash produced in the manufacture of water gas from the resulting carbon, as
lastly described, will contain the mineral manures of the sewage treated, and may
be employed for fertilizing purposes.
The series of shallow and deep settling tanks hereinbefore referred to, may be
sub-divided into two or more sets, so that whilst one set of tanks is being charged
with the sewage, the sludge deposited in another set of tanks may be removed, and
thus the operation may be continuously carried on.
The liquid drawn off from the shallow settling tanks, as hereinbefore described is
conducted into and distributed amongst a series of precipitating tanks, and carbonic
acid gas under pressure, and issuing from one or more jets, is passed or forced into
or through the same by any suitable means, such as a steam blower. The quantity
of carbonic acid gas required for that purpose can be readily ascertained by persons
conversant with like chemical operations.

page_text: The carbonate of lime precipitated in the manner hereinbefore described, will be
found suitable for use in the manufacture of glass and for other purposes.
When desired, in addition to treating the effluent liquid with carbonic acid gas,
in the manner hereinbefore described, we mix therewith a quantity of river mud
during the introduction of the carbonic acid gas, and the resulting compound of
river mud and carbonate of lime, which is allowed to settle, will form a valuable
stock for the manufacture of Portland cement.
After the precipitation of the carbonate of lime, the remaining liquid is, if
desired, passed through filters in which the filtering medium is composed of peat
charcoal, by preference made from peat litter obtained from stables, and the
liquid will then be found to be innocuous and free from organic and other injurious
matter.
The peat charcoal, when removed from the filters, will be impregnated with
ammonia and other organic matter, and will be suitable for mixing with the before
mentioned sludge prior to making the same into brickets, or blocks as above stated,
whereby the quality and quantity of gas produced from such sludge will be
improved and an increased quantity of ammonia recovered, as hereinbefore
described.
The apparatus required for carrying on the operations hereinbefore referred to,
will consist mainly of mixing machines and the necessary pumps, filters and tanks,
and the same may be of any well known, and suitable and convenient kind.
Having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The improvements in the treatment of sewage and in obtaining certain useful
products therefrom, substantially as herein described.
2. In the treatment of sewage the employment of sufficient quantity of lime, by
preference in the form of milk of lime, to more than saturate the water contained
therein, in order to more effectually precipitate the solid matter, substantially as
herein described.
3. In the treatment of sewage, the employment of lime, by preference in the form
of milk of lime, in sufficient quantity to more than saturate the water contained
therein, and finely pulverized slack coal in combination, substantially as herein
described.
4. In the treatment of sewage, the employment of finely pulverized coal in order
to assist the precipitation of the sludge and to afterwards render the sludge suitable
for the production of illuminating gas, substantially as herein described.
5. In the treatment of sewage, combining therewith lime, by preference in the
form of milk of lime, in sufficient quantity to more than saturate the water contained
therein, and fine coal in a suitable mixer, then passing the mass into two or more
sets of settling tanks where it is allowed to settle, then drawing off the liquid and
making the deposited sludge into brickets or blocks to be employed in the
manufacture of illuminating gas, substantially as herein described.
6. In the treatment of sewage, the employment of the carbon resulting from the
manufacture of illuminating gas for the production of water gas and the employment
of the residual tar and other products such as hydrocarbon oils from the
manufacture of illuminating gas to enrich the water gas, substantially as herein
described.
7. In the treatment sewage, submitting the liquid drawn off from the shallow
settling tanks to the action of carbonic acid gas in order to precipitate the contained
lime as carbonate of lime, and to render the effluent liquid comparatively pure,
substantially as herein described.
8. In the treatment of liquid sewage, to which has been added lime, by
preference in the form of milk of lime, the employment of carbonic acid gas and
river mud in combination, substantially as herein described and for the purpose
stated.

page_text: 9. In the treatment of sewage, passing the liquid resulting from the treatment
referred to in Claims 6. and 7. through a filter bed composed of peat charcoal
obtained by preference from stable litter and afterwards utilizing the charcoal,
substantially as herein described.
10. The combined process of treating sewage, substantially as herein described.
Dated this 20th day of April 1892.
VAUGHAN & SON,
Agents for the Applicants.