Improvements in the Manufacture of Materials or Compounds for Use in the Treatment of Sewage and Impure Waters.
Year: 1896

page_text: Date of Application, 19th Mar., 1890
Complete Specification Left, 18th Dec., 1896-4ccepted, 13th Mar., 1897
Complete Specification Left, 18th Dec., 1996-4ccepted, 13th Mar., 1897
Improvements in the Manufacture of Materials or Compounds for
Use in the Treatment of Sewage and Impure Waters.
I HARRY BLOOM SHARP of Elmfield, Heaton Moor Road, Heaton Moor, near
Stockport, in the County, of Lancaster, Chemist, do hereby declare the nature of
this invention to be as follows :-
My said invention relates to compositions or compounds adapted for use in the
treatment of sewage and foul waters and particularly to cases where such com-
pounds are made in the form of blocks or cakes which are used in the now well
known manner to effect the purification of sewage by causing the contained matter
to be separated from the water by precipitation.
In carrying my invention into effect I take a known quantity of ground and
finely sifted mill or "tap" cinders, chiefly a waste product from iron smelting
furnaces and containing a quantity of ferrous oxide of iron. I mix these siftings
with a sufficiency of water and heat in a suitable vessel. I then add a known
quantity of strong sulphuric acid whereby an action is set up resulting in the iron
becoming dissolved as ferrous sulphate. More water is then added and the residue
of the ore allowed to settle whereupon the liquid is run into another pan or vessel
where I mix with it a quantity of sifted ore containing aluminium oxide.
heat the mixture and add sulphuric acid whereby most of the added ore is quickly
dissolved: Part of the liquid in the first pan may now be admitted to the second
vessel and I boil the contents of the latter for about an hour to complete decom-
position, adding liquid from the first pan as the boiling mixture thickens. I then
add sodium nitrate to the boiling mixture in successive small portions, and the
sulphuric acid acting on this, liberates nitric oxide, a gas which acts as an oxydizing
agent on the ferrous sulphate contained in the mixture and converts it into ferric
sulphate. After the oxydation is complete the mixture is boiled down and con-
centrated to the requisite thickness, after which it may be run into moulds or
upon slabs, where it cools and becomes a hard cake or block. capable of being
readily handled' for use or transport.
When purifying sewage of such a nature that it can be more effectually treated
with a ferrous than with a ferric sulphate, I would considerably reduce the propor-
tion of sodium nitrate added as aforesaid to the boiling mixture. The result of
this would be that considerably less of the ferrous sulphate would be converted
into ferric sulphate, the unconverted ferrous sulphate in the resulting cake, acting
upon the sewage in the required manner.

page_text: Improvements in the Manufacture of Materials or Compounds for
Use in the Treatment of Sewage and Impure Waters.
1 HARRY BLOOM SHARP, of Elmfield, Heaton Moor Road, Heaton Moor,
near Stockport, in the County of Lancaster, Chemist, 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, that is
to say:-
My said invention relates to compositions or compounds adapted for use in the
treatment of sewage and foul waters and particularly to cases where such com-
pounds are made in the form of blocks or cakes which are used in the now well
known manner to effect the purification of sewage, by causing the contained matter
to be separated from the water by precipitation.
In carrying my invention into effect I take a known quantity (say 575 lbs.)
of ground and finely sifted mill or "tap" cinders or slag, chiefly a waste product
from mill or ball furnaces, and from puddling furnaces and containing a quantity
of ferrous oxide of iron. I then prepare a solution with which to treat the said
ground and sifted slag, the said solution, relatively to the herein before stated
weight of slag, consisting of a known quantity (say 780 lbs.) of strong sulphuric
acid placed in a wooden vat and diluted with twice its own weight of water.
When the said quantity of dilute sulphuric acid. has been allowed to cool I gradually
add thereto in small proportions the herein before stated quantity of ground and
sifted slag, agitation of the mixture being continuously kept up. The heat
generated by the reaction is quite enough to dissolve the slag without the appli-
cation of artificial heat, although in my Provisional Specification I stated that
I made use of such artificial heat. I then fill up the vat with water and after
allowing the contents to settle I run off the supernatant clear liquor which is a
strong solution of ferrous sulphate. The residue contains ferrous sulphate and
silica and the ferrous sulphate in the said residue may be extracted by adding hot
water and running into a hydro-extractor. I now run into a boiler a quantity
(say 400 lbs.) of the said ferrous sulphate solution and add thereto a known quantity
(say 207 lbs.) of finely ground and sifted ore containing aluminum and iron. To
this I now add a quantity of strong sulphuric acid (say 370 lbs.) and when the action
is finished and the ore dissolved I heat the boiler, and when ebullition takes place
..I gradually run in the rest of the .ferrous sulphate solution, to which I have
added a quantity (say 308 lbs.) of sodium nitrate, agitation being meanwhile kept
up. Oxydizing action is at once set up and nitric acid gas is liberated in con-
siderable volume. To collect this gas I cover the boiling pan with a hood
terminating in a pipe leading to a series of bottles containing water. An air
pump is used to draw the gas through the water with the result that I gain pure
nitric acid. The nitric oxide acts as an oxydizing agent on the ferrous sulphate
contained in the mixture and converts it into ferric sulphate. When the whole of
the ferrous sulphate solution has been added and the, oxydation of the contents of
the pan is complete, the hood or cover of the boiling pan is removed and the
mixture is boiled down and concentrated to the requisite consistency, after which
it may be run into moulds or upon slabs where it cools in the form of hard blocks
or cakes capable of being readily handled for use or transport.
When purifying sewage of such a nature that it can be more effectually treated
with a ferrous than with a ferric sulphate, I would considerably reduce the pro-
portion of sodium nitrate added as aforesaid to the boiling mixture. The result
of this would be that considerably less of the ferrous sulphate would be converted

page_text: into ferric sulphate, the unconverted ferrous sulphate in the resulting cake, acting
upon the sewage in the required manner.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is.
The improved manufacture of materials or compounds for use in the treatment
of sewage and impure waters substantially as hereinbefore set forth.
Dated this 17th day of December 1896.
For the Applicant,
E. K. DUTTON & Co.,
5 John Dalton Street, Manchester, Chartered Patent Agents.