IMPROVEMENTS IN APPARATUS FOR STIRRING OR AGITATING SOLID SUBSTANCES, AND FOR EXPOSING THEM TO THE ACTION OF THE AIR, GASES, AND VAPOURS
Year: 1867

page_text: LETTERS PATENT to Arthur McDougall, of the Firm of McDougall,
Brothers, of the City of Manchester, Manufacturing Chemists, for the
Invention of "IMPROVEMENTS IN APPARATUS FOR STIRRING OR AGITATING
SOLID SUBSTANCES, AND FOR EXPOSING THEM TO THE ACTION OF THE AIR, GASES,
AND VAPOURS."
Brothers, of the City of Manchester, Manufacturing Chemists, for the
Invention of "IMPROVEMENTS IN APPARATUS FOR STIRRING OR AGITATING
SOLID SUBSTANCES, AND FOR EXPOSING THEM TO THE ACTION OF THE AIR, GASES,
AND VAPOURS."
Sealed the 28th April 1868, and dated the 5th November 1867.
PROVISIONAL SPECIFICATION left by the said Arthur McDougall at the
Office of the Commissioners of Patents, with his Petition, on the
5th November 1867.
I, ARTHUR MºDOUGALL, of the Firm of McDougall, Brothers, of the City of
Manchester, Manufacturing Chemists, do hereby declare the nature of my said
Invention for "IMPROVEMENTS IN APPARATUS FOR STIRRING OR AGITATING SOLID
SUBSTANCES, AND FOR EXPOSING THEM TO THE ACTION OF THE AIR, GASES, AND
VAPOURS." to be as follows, that is to say:
This Invention relates to a peculiar construction, arrangement, and com-
bination of self-acting machinery or apparatus for turning over, stirring, or
agitating solid substances with a view to the more complete exposure of the
same to a current of air, gas, or vapour, and to the maintaining of a constant
supply or renewal of the substance to be subjected to the current of air, gas,
[Price 8d.]

page_text: or vapour without necessitating the arrest or diversion of such current
of air, gas, or vapour, and without involving any escape or loss of the
same. This peculiar self-acting apparatus is susceptable of various applica-
tions, amongst the most important of which I may mention the purification
of gas, whereby the gas is not only more effectually acted upon by the lime
or other purifying agent employed, but from the fact of the apparatus being
self-acting it causes a constant supply of fresh purifying material to pass
through it, and thus its action is rendered continuous, as will be herein-after
explained. The effects of the ordinary gas purifiers now employed are that
great labour is required in filling and emptying them, that the course of the
gas has often to be changed during these operations, and that a large quantity
of gas is lost at each removal of the lid or cover of the purifier. The said
apparatus is equally applicable for effecting the absorption of sulphuretted
hydrogen evolved by any suitable means from the block ash waste of alkali
makers, the absorption of carbonic acid by soda crystals, the absorption
of chlorine by lime, and as a self-acting kiln for malt and other grain.
In adapting this self-acting apparatus to the purification of gas, I con-
struct a cylindrical closed vessel which is connected by pipes with the gas
holder, and in the centre thereof I introduce a vertical shaft supported
in its central position by suitable bearings, and receiving a rotatory motion
by the aid of bevel wheels or other gearing driven by any convenient
prime mover. At suitable intervals along the interior of the cylindrical vessel
are fitted two or more open or perforated floors of wirework, metal, earthen-
ware, or other suitable material, through the centre of which the vertical shaft
revolves freely. To this shaft, and a little above the surface of each of the
open or perforated floors, there is secured a cross arm extending nearly from
side to side of the cylindrical vessel. Each of these arms carries a number
of plates or stivers so arranged as to tend when revolving in the proper
direction to gradually urge or move the gas purifying agent contained upon
the perforated floor from the centre to the circumference thereof, and at the
same time to turn over such substance after the manner of the turnfurrow of
a plough. In this way it is obvious that a complete stirring or turning
of the material will be accomplished. One or more discharge openings are
left in the circumference of each floor, in order that the lime or other agent
employed on reaching the circumference may drop into suitable vessels or
receptacles; or (which I prefer in a gas purifier) may drop into the mouth of an
archimedean screw or other equivalent feeder, situate immediately beneath
the floor, which feeder will convey the lime or other substance to the centre
of the next floor below, & so on throughout the series of floors. I form a

page_text: chamber underneath the lower floor, into which the gas to be purified is
admitted by a pipe through the side of the cylindrical vessel, and then passes
floors and through the lime or other
up through the several perforated
purifying agents contained thereon. At the top of the apparatus there is a
double feeding hopper or a hopper divided into two separate compartments,
each of which is provided with an inlet and onlet aperture capable of being
closed gas tight by a sliding door or otherwise, which arrangement combined
with a self-acting elevator for raising the substance discharged from the bottom
floor to the double-feed hopper affords facility for maintaining a constant
supply of the purifying agent through the apparatus without interfering with
the flame of the gas or incurring loss or escape of gas by opening the purifyer
for filling or emptying. For this purpose I use the. two halves of the double-
feed hopper alternately, the one hopper filling whilst the other is emptying
itself on to the upper perforated floor of the series. When oxide of iron or
other metal is the substance employed for absorbing sulphuretted hydrogen
the bottom floor should not have the gas containing the sulphuretted hydrogen
passed through it, but should be connected with a powerful air draught, so
that the air passing through it may act as a revivifier of the working oxide.
The oxide is then discharged as before described into an elevator, and again
passed through the apparatus. In the case of using lime for purifying gas,
the draught of air above referred to will remove most of the offensive smell
from the lime. A double-feed hopper with valves like the top one above
described, is fitted between the closed bottom gas floor or chamber (above
which the gas enters) and that through which the air is drawn so as to
prevent air from passing up and mixing with the gas, and vice versa. These
double hoppers will be required, whatever purifying material may be used to
shut off all connection between the gas chambers and the outer atmosphere.
When found requisite the passage of gas, air, or vapour through the apparatus
above described, may be facilitated by any suitable forcing or exhausting
apparatus in connection with the cylindrical vessel above referred to.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Arthur McDougall in the Great Seal Patent Office on the
5th May 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ARTHUR
MCDOUGALL, of the Firm of McDougall, Brothers, of the City of Manchester,
Manufacturing Chemist, send greeting.

page_text: WHEREAS Her. most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of November, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirty-first year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Arthur M Dougal, Her special license that I, the said Arthur McDougall,
my executors, administrators, and assigns, or such others as I, the said
Arthur McDougall, my executors, administrators, or assigns, should at any time
agree with, and no others; from time to time and at all times thereafter during
the term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
APPARATUS FOR STIRRING OR AGITATING SOLID SUBSTANCES, AND FOR EXPOSING THEM
TO THE ACTION OF THE AIR, GASES, AND VAPOURS," upon the condition (amongst
others) that I, the said Arthur McDougall, my exécutors or administrators,
by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
IN
NOW KNOW YE, that I, the said Arthur McDougall, do hereby declare the
nature of my said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement.
reference being had to the accompanying Drawings, and to the letters and
figures marked thereon, that is to say:-
My said Invention relates to a peculiar construction, arrangement, and
combination of self-acting machinery or apparatus for turning over, stirring.
or agitating solid substances with a view to the more complete exposure of
the same to a current of air, gas, or vapour, and to the maintaining of a
constant supply or renewal of the substance to be subjected to the current of air,
gas, or vapour, without necessitating the arrest or diversion of such current of
air, gas, or vapour, and without involving any escape or loss of the same.
This peculiar self-acting apparatus is susceptable of various applications,
amongst the most important of which I may mention the purification of gas,
whereby the gas is not only more effectually acted upon by the time or other
purifying agent employed, but from the fact of the apparatus being self-
acting it causes a constant supply of fresh purifying material to pass through
it, and thus its action is rendered continuous, as will be herein-after
explained. The defects of the ordinary gas purifiers now employed are that
great labor is required in filling and emptying them, that the course of the

page_text: gas has often to be changed during these operations, and that a large quantity
of gas is lost at each removal of the lid or cover of the purifier. The said
apparatus is equally applicable for effecting the absorption of sulphuretted
hydrogen evolved by any suitable means from the black ash waste of alkali
makers, the absorption of carbonic acid by soda crystals, the absorption of
chlorine of lime, and as a self-acting kiln for malt and other grain.
And in order that my said Invention may be fully understood; I shall now
proceed more particularly to describe the same, and for that purpose shall
refer to the two. Figures on the annexed Sheet of Drawings; the same letters
of reference indicating corresponding parts in both the Figures.
Figure 1 of my Drawings represents a vertical section of one form of my
improved self-acting apparatus as adapted for the purification of coal gas, and
Figure 2 is a corresponding half-plan of the same.
A is a cylindrical closed vessel, which is connected by an outlet pipe B
with the gas holder, and is furnished with a gas inlet pipe B', through which
the gas to be purified enters the purifier, each of which pipes is provided with
a sliding valve or sluice. In the centre of the cylindrical vessel A, I introduce
a vertical shaft C, supported in its central position by suitable bearings D, D,
and receiving a rotatory motion by the aid of bevel wheels or other gearing
E, F, driven by a strap G or otherwise from any convenient prime mover.
At suitable intervals along the interior of the cylindrical vessel A are fitted
two or more open or perforated floors H, H, of wirework, metal, earthen-
ware, or other suitable material, through the centre of which the vertical
shaft C revolves freely. In my drawing I have shown five of these floors.
To this shaft, and a little above the surface of each of the open or perforated
floors H there is secured a cross arm I, extending nearly from side to side of
the cylindrical vessel. Each of these arms carries a number of plates or
stirrers a, a, so arranged as to tend when revolving in the proper direction to
gradually urge or move the gas purifying agent contained upon the perforated
floor H from the centre to the circumference thereof, and at the same time to
In
turn over such substance after the manner of the turnfurrow of a plough.
this way it is obvious that a complete stirring or turning over of the material
will be accomplished. One or more discharge openings b, b, are left at or
near the circumference of each floor, in order that the lime or other agent
employed on reaching the circumference may drop into suitable vessels or
receptacles, or (which I prefer in a gas purifier) may drop into the mouth of
a trough or box K, containing an archimedian screw or other equivalent
feeder driven from the vertical shaft C by the aid of bevel or other suitable
gearing c, c, and situate immediately beneath cach floor H, which feeder will

page_text: convey the lime or other substance to the centre of the next floor below, and
so on throughout the series of floors. I form a chamber L underneath the
lower floor, into which the gas to be purified is admitted by the pipe B¹
through the bottom of the cylindrical vessel A, and then passes up through
the several perforated floors H and through the lime or other purifying agents
contained thereon, and passes out in a purified condition through the pipe B
leading to the gas holder. At the top of the apparatus there is a double feeding
hopper M, M¹, or a hopper divided into two separate compartments, which
are provided at the top with inlet apertures or supply pipes N, N¹, and outlet
apertures 0, 0¹, at the bottom, such inlet and outlet apertures being capable
of being closed gas tight by sliding doors at P, P¹, and Q, Q, or otherwise.
The supply pipes N, N', are in communication with the upper end of a self-
acting elevator R for raising the substance discharged from the bottom floor
H to the double feed hopper M, M¹, by which arrangement facility is
afforded for maintaining a constant supply of the purifying agent through the
apparatus without interfering with the flow or passage of the gas, or incurring
loss or escape of gas by opening the purifier for the purpose of filling or
emptying the same. For this purpose I use the two compartments of the
double feed hopper alternately, the one hopper filling whilst the other is
emptying itself onto the upper perforated floor of the series. When oxide of
iron or other metal is the substance employed for absorbing sulphuretted
hydrogen the bottom floor H' should not have the gas containing the
sulphuretted hydrogen passed through it, but should be connected with a
powerful air draught, so that the air passing through it may act as a
revivifier of the working oxide. The oxide is then discharged into an elevator
through the discharge pipe S, and again passed through the apparatus. This
discharge pipe S is provided with a branch outlet S¹, through which the
substances may be discharged when exhausted in lieu of being returned to
the elevator, sliding doors or valves d and e being provided in the discharge
pipes S, S¹, for directing the discharge. In the case of using lime for
purifying gas the draught of air above referred to will remove most of the
offensive smell from the lime. A double feed hopper T, T¹, provided with
valves U, U¹, and V, VI, like the top hopper herein-before described, is fitted
between the closed bottom, gas floor, or chamber L (above which
the gas
enters) and the chamber W, through the perforated floor H₁ of which the
air is drawn along the outlet pipe X leading to an exhauster, so as to prevent
air from passing up and mixing with the gas, and vice versa. These double
hoppers will be required whatever purifying material may be used, in order to
shut off all connection between the gas chambers and the outer atmosphere.

page_text: When found requisite the passage of gas, air, or vapour through the apparatus
above described may be facilitated by any suitable forcing or exhausting
apparatus in connection with the cylindrical vessel above, referred to.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used or carried into
effect, I would observe in conclusion that what I consider to be novel and
original, and therefore claim as the Invention secured to me by the herein-
before in part recited Letters Patent is,-
First, the peculiar construction, arrangement, and combination of apparatus
for stirring or agitating solid substances, and for exposing them to the action
either of air, gases, or vapours, as herein-before described and illustrated by
my Drawings.
Second, the renewal of the purifying agent in gas purifiers, and the stirring
or agitating of such agent whilst in the purifier without incurring escape or
loss of gas, by the combination of double feed and discharge hoppers with
rotatory stirrers and an elevator, the whole being arranged and operating
together substantially in the manner herein-before described.
Third, the application and use to and in the purification of gas, the
adsorption of sulphuretted hydrogen evolved from the black ash waste of
alkali makers, the absorption of carbonic acid by soda crystals, the absorption
of chlorine of lime, and the stirring or agitating of grain in the process of
malting, of a self-acting apparatus constructed and operating substantially in
the manner herein-before described.
Fourth, the combination of a series of perforated or open work floors, with
revolving arms or stirrers and archimedian screws or their equivalents
operating together in a closed vessel or chamber, substantially as and for the
purpose herein-before described and illustrated by my Drawings.
In witness whereof, I, the said Arthur McDougall, have to this my
Specification set my hand and seal, the Fourth day of May, One
thousand eight hundred and sixty-eight.
ARTHUR MCDOUGALL. (L.S.)