Improvements in the Construction of. Apparatus for Making Bisul- phites or other Compounds Used in the Treatment of Wood Pulp and other Fibrous Materials or the like.
Year: 1888

page_text: Improvements in the Construction of. Apparatus for Making Bisul-
phites or other Compounds Used in the Treatment of Wood Pulp
and other Fibrous Materials or the like.
We ISAAC SHIMWELL MCDOUGALL and JAMES THOMAS MCDOUGALL both of
Irk Vale Chadderton near Manchester Manufacturing Chemists RICHARD KENT
HARTLEY of Springwood House Chadderton near Oldham Chemist and THOMAS
SUGDEN of 84 Greengate Street Oldham aforesaid Engineer all in the County of
Lancaster do hereby declare the nature of this Invention to be as follows:-
This Invention has for its object to provide apparatus for the absorption of
sulphurous acid gas for the formation of Bisulphites and the like such that a con-
tinuous flow of solutions of acid or its compounds required for instance in the
manufacture of wood pulp or other fibrous materials for the condensation of such
acid gas takes place without the necessity of its being forced through a depth of
liquid and so as to attain the required degree of absorption without the aid of the
pressure hitherto necessary.
We produce sulphurous acid gas by burning sulphur or sulphur compounds in an
open vessel or retort in the usual way and the heated gases so produced may be cooled
before passing to the arrangement of apparatus, according to our invention which
consists as follows.
A series of vessels in the form of vertical towers and made of suitable material to
resist the action of the acid employed is provided and the interior of each vessel or
tower is provided with perforated plates or distributors at distances apart for the
purpose of distributing the liquor and so
obtaining more complete absorption of the
gas to be absorbed. These vessels or towers are made with coned bottoms terminating
in pipes which are provided with a rotary pumping device and extend upwards and
open into the top of the next vessel or tower, pipes for the gas open from the top of
each of the vessels or towers and descends and opens into the lower part of the
adjacent vessel the arrangement being such that the liquid passes in one direction
and the gases in the opposite direction. The gas is admitted some little distance
TD 11/1

page_text: above the bottom of the first vessel or tower and passes therethrough to the outlet
near or at the top and then is brought down to or near to the bottom of the next
vessel or tower then up therethrough and so on to the end of the series, the liquid to
be saturated is admitted at or near the top of the vessel or tower at the opposite end
of the series of vessels or towers to the end at which the gas enters and passes down
through the said vessel or tower to the outlet at the bottom of the vessel or tower and
is then pumped up to the top of the next vessel and so on through the series meeting
the gases as they flow through the vessels or towers. The conical form of the bottom
of the vessels or towers prevents any accumulation of sediment and ensures the flow
of the liquid and sediment to the pump or elevator which by mechanical means is
caused to lift them continuously to the top of the next vessel or tower of the series
and this operation is continued. The gases and liquids are thus passed in opposite
directions from one vessel or tower to the next throughout the series through such
number of vessels or towers as is found suitable for the degree of absorption of the
gases and saturation of the liquids required.
The vessels or towers are provided with doors at different heights for convenience
in cleaning repairing or removing the perforated plates or distributors of the liquids.
In order to accelerate the velocity of the gases through the vessels or towers, at the
extremity of the series a chimney draught or fan or other suitable appliance may be
used.
1000
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C.,
Agents.

page_text: Improvements in the Construction of Apparatus for Making Bisul-
phites or other Compounds Used in the Treatment of Wood Pulp
and other Fibrous Materials or the like.
We ISAAC SHIMWELL MCDOUGALL and JAMES THOMAS MCDOUGALL both, of Irk
Vale Chadderton near Manchester Manufacturing Chemists RICHARD KENT HARTLEY
of Springwood House Chadderton near Oldham Chemist and THOMAS SUGDEN of
84 Greengate Street Oldham aforesaid Engineer all in the County of Lancaster 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:
This Invention has for its object to provide apparatus to effect the absorption of
sulphurous acid gas for the formation of bisulphites and the like such apparatus being
so arranged that a continuous flow of such acid of the absorbing liquor and of the
resultant solutions of acid or its compounds required for instance in the manufacture
of wood pulp or other fibrous materials takes place without the necessity for the said
gas being forced through a depth of liquid and so as to attain the required degree of
aborption of the gas by the liquor without the aid of the pressure hitherto necessary.
We produce sulphurous acid gas by burning sulphur or sulphur compounds in a
vessel or retort (either open or closed) in the usual way and the heated gases so
produced may be cooled before passing to the arrangement of apparatus according to
our invention which consists as follows and is illustrated by the accompanying
Drawings Figure 1 of which is an elevation with one of the towers in section and
Figure 2 is an elevation of one of the towers at right angles to Figure 1.
A series of vessels A in the form of vertical towers and made of suitable material
to resist the action of the acid employed (such as for instance of iron lined with lead
or of wood or earthenware) is provided and the interior of each vessel or tower is
provided with perforated plates or distributors a at distances apart suitable for the
purpose of distributing the liquor and so obtaining more complete absorption of
the gas to be absorbed. These vessels or towers are made with coned bottoms b
terminating in pipe which are provided with a rotary pumping device or its
equivalent B the said pipe extending upwards and opening into the top of the
same or of the next or a succeeding vessel or tower but preferably into the same
tower as shown in the drawings. Pipes C for the gas open from the top of each of
the vessels or towers and each of these pipes descends and opens into the lower part
of the adjacent vessel the arrangement being such that the liquid passes in one
direction and the gases in the opposite direction. The gas is admitted some little distance
above the coned bottom of each of the vessels or towers A and passes therethrough to

page_text: the outlet near or at the top and then is brought down to or near to the bottom of the
next vessel or tower then up therethrough and so on to the end of the series. The
liquid to be saturated say for instance lime water is prepared in a suitable tank D and
is fed as required into the mixing tank E and therefrom is passed by the pipe e
furnished with a regulating cock e into the coned part of the adjacent tower A and
when it reaches the level of the outlet pipe f therefrom it passes into the coned bottom of
the next tower A and so on from one tower to the other by the pipes which open at
their outlet ends at such a higher level than their inlet ends that a level of liquid is
constantly maintained in the coned bottoms of the towers A. The pumps B pass the
liquor up by the pipes into the upper part of each tower so that the liquor passes
down in one direction and the gas flows up in the opposite direction throughout
the series of vessels or towers A. The conical form of the bottom of the vessels
or towers prevents any accumulation of sediment and ensures the flow of the liquid
and sediment to the pumps or elevators which continuously lift the liquor to the top
of each vessel or tower of the series and this operation is continuous whilst the
apparatus is at work. The gases and liquids are thus passed in opposite directions
from one vessel or tower to the next throughout the series through such number of
vessels or towers as is found suitable for the required degree of absorption of the
gases and saturation of the liquids.
The vessels or towers are provided with doors A² at different heights for con-
venience in cleaning repairing or removing the perforated plates or distributors of
the liquids.
In order to pass the gases through the vessels or towers a chimney draught or
fan or other suitable appliance may be used at the extremity of the series.
We have shown for the purpose a fan at F in the drawing or the gases can be
forced through the apparatus instead of being drawn through. We have shown a
retort at Gand coolers at H for the purpose of generating and cooling the gas
to be passed through the towers A.
We have shown more in detail in Figure 3 a part of an earthenware tower
where the parts which correspond with those shown in Figures 1 and 2 are marked
with the same letters of reference. The perforated plates are shown as being made in
pieces supported on the ledges i to enable them to be put in and removed by the
doors.
After the gases pass from the last tower of the series they may if desired be caused
to pass through a depth of liquid which may be that which is used for feeding the
towers as illustrated at J. or the gases may be allowed to pass off without this
arrangement.
Having now particularly described and ascertained the nature of our said inven-
tion. and in what manner the same is to be performed we declare that what we
claim is :-
1. In apparatus for the purposes mentioned the combination with the towers or
vessels A and means for supplying gas and liquor thereto of pipes or passages leading
from the lower part of one tower or vessel to the upper part of the same or another
tower or vessel and means for elevating the liquor so that the gas and the liquor pass
through the towers or vessels A in reverse directions substantially as hereinbefore
described.
2. In apparatus for the purposes mentioned towers having coned lower portions
with an outlet at bottom substantially as and for the purpose described.
3. In apparatus for the purposes described towers or vessels A provided with
perforated plates and with doors for giving access to each such plate substantially
as and for the purpose described.
4. In apparatus for the purposes mentioned towers having coned lower portions and
Pipes or passages leading from each coned lower portion to the adjacent one the
outlet and inlet ends of such pipes being at different levels so as to maintain a supply
of liquid in the said coned lower portions substantially as herein before described.

page_text: 5. In apparatus for the purposes mentioned towers or vessels A provided with
coned lower portions and pipes leading from each coned lower portion as claimed by
the last preceding claiming clause in combination with a pipe or. passage for liquid
from the lower to the upper part of the tower and a pump or forcing device
substantially as hereinbefore described.
6. The general arrangement and combination of parts constituting the apparatus
substantially as and for the purposes hereinbefore described and substantially as
illustrated in the accompanying drawings.