An Improved Method or Process of and Apparatus for Removing Gaseous Iron Compounds from Water-gas.
Year: 1896

page_text: Date of Application, 31st July, 1896
Complete Specification Left, 2 th Apr., 1897-Accepted, 12th June, 1397
PROVISIONAL SPECIFICATION.
An Improved Method or Process of and Apparatus for Removing
Gaseous Iron Compounds from Water-gas.
I, Dr. HUGO STRACHE, of 14, Alserstrasse, Vienna IX, in the Empire of Austria,
Lecturer at the K. K. Technische Hochschule, do hereby declare the nature of this
invention to be as follows:-
Water-gas contains, as is known, a gaseous iron compound (iron carbon-oxide or
iron carbonyl) which in burning, produces iron oxide and thus deprives the
incandescent mantles or bodies, which are used for lighting with water-gas, of their
illuminating power. For removing this iron-compound, the water-gas is washed with
acids.
The present invention relates to an improved method and apparatus which enable
the water-gas to be thoroughly cleansed or purified from the iron which it contains by
means of concentrated sulphuric acid. Essentially this is effected by bringing the
gas into contact with the acid over as large a surface as possible, first drying the gas
by the acid which runs away after having served for taking up the iron, since other wise
the sulphuric acid is too rapidly diluted and in the dilute condition it can no longer
take up the iron.
In my apparatus a large surface of contact of the acid with the gas is obtained by
dropping the said acid onto pumice stone over which the gas is caused to pass in a
scrubber or like apparatus lined with lead. Moreover the desiccation of the gas is
effected by the acid which runs away, by following the reverse current principle, since
the dropping acid flows from above downwards over the pumice, whilst the gas passes
over the same from below upwards, and is thus first dried in the lower parts of the
apparatus by diluted acid and, in rising, always meets layers of gradually increasing
concentration and is finally purified, in a perfectly dry condition, in the uppermost
parts of the apparatus, by fully concentrated acid.
Since concentrated sulphuric acid can free almost unlimited quantities of dry
water-gas from iron, the quantity of sulphuric acid necessary for cleansing is
determined entirely by the necessary desiccation of the gas. In my apparatus the
sulphuric acid is so advantageously utilized, that it flows away at the bottom diluted
with more than an equal volume of water. Since now 1 cubic metre of a gas
saturated with moisture at ordinary temperatures contains about 2 volumes per cent.
(=20 litres = 16 grammes) of water-vapour, 16 grammes of concentrated sulphuric
acid will suffice for drying and purifying 1 cubic metre of water-gas, so that for each
100 cubic metres of water-gas only 1-6 kilogrammes of concentrated sulphuric acid
are necessary.
From the above it follows that, for example, in an apparatus for purifying
100 cubic metres of water-gas per hour, less than 0.5 gramme of sulphuric acid must
be supplied per second, and that a suitable arrangement is required for uniformly
distributing so small a quantity of fluid over the surface of the pumice.
In my apparatus, this arrangement consists of a small arched or curved lead disc
which is arranged in the centre of the purifier somewhat above the surface of the
pumice filling, and on which drops of the concentrated sulphuric acid are allowed to
fall from a height of about 1.5 metre, through a pipe, by means of a funnel and cock,
these drops being sprayed by their impact on the lead disc and uniformly moistening.

page_text: the surface of the pumice. It is obvious that in larger purifiers several of such
spraying devices can be employed.
The diluted acid running away can either be sold for use for other purposes or he
concentrated by evaporation in lead pans and again used in the process.
Dated this 30th day of July 1896.
D. YOUNG & Co.,
11 & 12, Southampton Buildings, London, W.C.,
Agents for the Applicant.
An Improved Method or Process of and Apparatus for Removing
Gaseous Iron Compounds from Water-gas.
I, Dr. HUGO STRACHE, of 14 Alserstrasse, Vienna IX, in the Empire of Austria,
Lecturer at the K. K. Technische Hochschule, 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 :-
Water-gas contains, as is known, a gaseous, iron compound (iron carbon-oxide or
iron carbonyl) which in burning, produces iron oxide and thus deprives the
incandescent mantles or bodies, which are used for lighting. with water-gas, of their
illuminating power. For removing this iron-compound, the water-gas is washed with
acids.
The present invention relates to an improved method and apparatus which enable
the water-gas to be thoroughly cleansed or purified from the iron which it. contains,
by means of concentrated sulphuric, acid. Essentially, this is effected by bringing the
gas into contact with the acid over, as large a surface as possible, first drying the gas
by the acid, which runs away after having served. for, taking up the iron, since
otherwise, the sulphuric acid is too rapidly diluted and in the dilute condition it can no
longer, take up the iron.
In the accompanying drawing. I have shown my improved apparatus in vertical
central section.
In, my apparatus a large surface of contact of the, acid with the gas is obtained by
dropping the said acid onto pumice, stone over which the gas is caused to pass in a
scrubber a or, like apparatus. lined: with lead: Moreover, the desiccation of the gas is
affected by the acid.which runs away, by following the, reverse current principle, since
the dropping acid flows from above downwards over-the pumice, whilst the gas passes
over the same, from, below, npward:
In the arrangement shown the gas enters through the inlet.e into.a chamber f and
passes up through the perforated false bottom into. the purifying chamber a where it
comes into contact with the acid and leaves. the apparatus through the outlet h. In
this manner, the gas.is first,dried in the lower parts of the apparatus by diluted acid
and, in rising, continually. meets layers of acid of gradually increasing concentration,
being finally purified in the uppermost parts of the apparatus, in a perfectly dry.
condition, by.fully..concentrated acid.
Since concentrated sulphuric acid can free almost unlimited quantities. of dry.
water-gas from, iron, the quantity. of sulphuric acid necessary, for cleansing is.
determined entirely by, the necessary desiccation of. the gas. In my apparatus, the
sulphuric acid is so advantageously, utilized; that it flows. away through the liquid
seal jat, the, bottom, of the, chamber f, diluted with more than an equal volume, of
water. Since now, 1; cubic metre, of a gas, saturated with. moisture at ordinary.
temperatures contains about. 2 volumes per cent. (= 20 litres = 16 grammes) of water-
vapour, 16.grammes of concentrated sulphuric acid will suffice for drying, and purifying-

page_text: 1 cubic metre of water-gas, so that for each 100 cubic metres of water-gas only
1-6 kilogrammes of concentrated sulphuric acid are required.
From the above it follows that, for example, in an apparatus for purifying 100 cubic-
metres of water-gas per hour, less than 0.5 gramme of sulphuric acid must be supplied
per second, and that a suitable arrangement is required for uniformly distributing so-
small a quantity of fluid over the surface of the pumice.
In my apparatus this arrangement consists of a small arched or curved lead disc or
plate 6 which is arranged in the centre of the purifier a somewhat above the surface of
the pumice filling, and on which drops of the concentrated sulphuric acid are allowed.
to fall from a height of about 15 metre, through a pipe c, by means of a funnel and
cock, or pin-valve d, these drops being sprayed by their impact on the lead disc b and
uniformly moistening the surface of the pumice, the acid being supplied from a
reservoir k provided with suitable filling and emptying devices l, m. It is obvious.
that in larger purifiers several of such spraying devices can be employed.
The diluted acid running away at j can either be sold for use for other purposes or
be concentrated by evaporation in lead pans and again used in the process.
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 :-
1. An apparatus for drying and purifying water-gas by means of concentrated.
sulphuric acid, comprising a vessel which is lined with lead and filled with pumice or
the like, and is provided with a device for spraying the falling concentrated acid,
substantially as, and for the purposes, herein before described.
2. In an apparatus such as is hereinbefore described, a spraying device consisting of
a curved sheet-metal disc or plate which is arranged in the purifying chamber above
the pumice-filling and on which drops of concentrated sulphuric acid are allowed to.
fall through a pin-valve or the like, substantially as described.
Dated the 26th day of April 1897
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.