Improvements in the Recovery of Sulphur from the Waste Gases from Claus Kilns or similar Gases, and Apparatus therefor.
Year: 1892

page_text: Date of Application, 16th Mar., 1892
Complete Specification Left, 13th Dec., 1892-Accepted, 21st Jan., 1893
PROVISIONAL SPECIFICATION.
Improvements in the Recovery of Sulphur from the Waste Gases
from Claus Kilns or similar Gases, and Apparatus therefor.
We, ALFRED ALLHUSEN of Musgrave House, Gateshead, Chemical Manu-
facturer GEORGE Edward EDGELL of 8 Catherine Terrace Gateshead Engineer
and WILLIAM RUSSELL of 9 Ely Street, Gateshead Analytical Chemist all in the
County of Durham do hereby declare the nature of this invention to be as
follows:-
The waste gases issuing from what are known as Claus kilns and similar gases
usually contain a considerable quantity of free sulphur in a fine state of division as
well as sulphur in chemical combination as sulphuretted hydrogen and as
sulphurous acid.
The object of this invention is to recover the whole or nearly the whole of the
free sulphur contained in the said waste gases which sulphur has hitherto
been lost.
According to this invention we pass the gases to be treated (such as those from
the Claus Kilns for instance after they have traversed the flower of sulphur
chambers) through a filtering medium kept at a temperature sufficiently elevated to
cause the sulphur to melt. As the said filtering medium we may use a porous
material such as oxide of iron or broken bricks or other suitable substance. Care
must be taken that air does not mix with the gases before they have passed through
the filtering medium as air would cause the sulphur to partially, or wholly burn
into sulphurous acid. The melted sulphur passing from the filtering medium may
be collected in any suitable receptacle. The gases are thus deprived of all, or
nearly all, of the free sulphur contained in them, and they may after being so
deprived be burnt with air or treated in any usual manner.
An apparatus suitable for the purposes of this invention consists of a chamber
preferably of brick and heated by any suitable furnace or heating device. Within
this chamber are pipes or passages (preferably cast iron pipes) communicating both
at top and at bottom with an airtight chamber or space. The upper chamber or
space is provided with an inlet through which the gases enter. The said pipes or
passages contain the filtering medium which may be supported on gratings. The
lower chamber or space serves as a receptacle for the molten sulphur and is
provided with a closable opening through which the sulphur can be removed from
time to time. The lower chamber is also provided with an outlet for the gases after
they have passed through the filtering medium in the pipes or passages and so been
deprived of the free sulphur and the said gases may be then treated as is now usually
done with waste-gases from Claus kilns.
The pipes or passages containing the filtering medium if not vertical should be
sufficiently inclined to allow the molten sulphur to flow out freely.
Dated this 16th day of March 1892.

page_text: COMPLETE SPECIFICATION.
Improvements in the Recovery of Sulphur from the Waste Gases
from Claus Kilns or similar Gases, and Apparatus therefor.
We, ALFRED ALLHUSEN of Musgrave House, Gateshead, Chemical Manu-
facturer GEORGE EDWARD EDGELL of 8 Catherine Terrace, Gateshead, Engineer
and WILLIAM RUSSELL of 9 Ely Street, Gateshead, Analytical Chemist, all in the
County of Durham, 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 :-
The waste gases issuing from what are known as "Claus kilns" and similar gases
usnally contain a considerable quantity of free sulphur in a fine state of division as
well as sulphur in chemical combination as sulphuretted hydrogen and as
sulphurous acid.
The object of this invention is to recover the whole or nearly the whole of the
free sulphur contained in the said waste gases which sulphur has hitherto
been lost.
Care
According to this invention we pass the gases to be treated (such as those from
the Claus kilns for instance after they have traversed the flower of sulphur
chambers) through a filtering medium kept at a temperature sufficiently elevated to
cause the sulphur to melt. As the said filtering medium we may use a porous
material such as oxide of iron or broken bricks or other suitable substance.
must be taken that air does not mix with the gases before they have passed through
the filtering medium as air would cause the sulphur to partially, or wholly, burn
into sulphurous acid. The melted sulphur passing from the filtering medium may
be collected in any suitable receptacle. The gases are thus deprived of all, or
nearly all of the free sulphur contained in them but they still contain sulphuretted
hydrogen or sulphurous acid or both and may afterwards be burnt with air or
treated in the known or any suitable manner for the recovery of the sulphur con-
tained therein as sulphuretted hydrogen or sulphurous acid.
We do not confine ourselves to any particular form of apparatus in which to carry
out this invention but we have illustrated in the accompanying drawings apparatus
we have found to answer well in practice.
Figures 1 and 2 are sectional elevations at right angles to each other and
Figure 3 is a sectional plan of the apparatus which consists of a brick chamber A
heated by the furnace B. Within the chamber A vertical cast iron pipes or
cylinders C C are placed the said pipes or cylinders communicating at the top with
the airtight chamber D which is provided with the inlet E through which the afore-
said waste gases enter the chamber D and then descend through the cylinders C.
At the bottom these cylinders communicate with another airtight chamber F which
serves as a receptacle for the melted sulphur.
The gases leave this chamber by the outlet G, and may thereafter be treated as
Claus kiln gases usually are treated.
The pipes or cylinders C C are filled with the filtering medium supported on
suitable iron gratings c. As filtering medium we prefer oxide of iron such as is
used for filling Claus kilns, but broken bricks or any other material capable of
withstanding the action of the gases and the elevated temperature may be employed.
As the gases pass through the hot filtering medium in the pipes or cylinders C the
particles of sulphur contained therein impinge upon the hot surfaces of the filtering
material and collect into a stream of melted sulphur gradually flowing downwards
into the chamber F from which the sulphur may be removed from time to time
through a door at H.
If the cylinders C C be of comparatively small diameter a number of them should
he employed as shewn so that the gases are not caused to travel too fast. They need

page_text: not necessarily be vertical but if not vertical should be sufficiently inclined to permit
the melted sulphur to flow away freely.
The pipes or chambers C are kept hot by the products of combustion from the
furnace B which pass around the said pipes at the parts situated in the space I
above the chamber F and below the chamber D and issue into a chimney by the
flue K.
If instead of a number of pipes or chambers C as shewn one large container be
used we prefer to construct it so that the filtering medium is contained in an annular
space between two concentric cylinders of cast-iron the fuel gases passing through
the internal cylinder and also around the external cylinder.
Or the large cylinder containing the filtering medium may be traversed vertically
or horizontally by cast iron flues through which the fuel gases pass to keep the
filtering medium hot.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we wish it to be understood
that we do not claim the recovery of sulphur from mixtures of sulphuretted
hydrogen and air by means of heated oxide of iron but what we claim as our
invention is:-
1. The recovery of free sulphur from gases from Claus kilns or other gases con-
taining free sulphur in a fine state of division by passing such gases through a hot
filter or hot filters substantially as herein before described.
2. An apparatus for the purpose described and claimed the said apparatus con-
sisting of a chamber and furnace within which are placed pipes, cylinders or recep-
tacles containing a filtering medium and connected with supply and discharge
chambers for the purposes set forth and substantially as hereinbefore described.
Dated this 13th day of December 1892.
J. H. JOHNSON & Co.,
Agents.