IMPROVEMENTS IN THE MANUFAC- TURE OR PRODUCTION OF CARBONIC ACID FROM THE CARBONATES OF CALCIUM, MAGNESIUM, STRONTIUM AND BARIUM AND APPARATUS THEREFOR
Year: 1883

page_text: LETTERS PATENT to William Lloyd Wise of 46 Lincoln's Inn Fields, in the
County of Middlesex for an Invention of IMPROVEMENTS IN THE MANUFAC-
TURE OR PRODUCTION OF CARBONIC ACID FROM THE CARBONATES OF CALCIUM,
MAGNESIUM, STRONTIUM AND BARIUM AND APPARATUS THEREFOR a communication
from Dr Hubert Grouven a person resident at Leipzig Saxony, in the German
Empire
PROVISIONAL SPECIFICATION left by the said William Lloyd Wise at the
Office of the Commissioners of Patents on the 16th August 1883.
WILLIAM LLOYD WISE of 46 Lincolns Inn Fields in the County of Middlesex
"IMPROVEMENTS IN THE MANUFACTURE OR PRODUCTION OF CARBONIC ACID FROM
AND BARIUM AND
THE CARBONATES OF CALCIUM, MAGNESIUM, STRONTIUM
APPARATUS THEREFOR"-(a communication from D Hubert Grouven a person
resident at Leipzig, Saxony in the German Empire)
It is known that if through a red hot pipe filled with pieces of limestone,
dolomite, or strontiunite superheated steam be passed, an evolution of carbonic acid
takes place even at a moderate red heat, and after a certain time the minerals in
question become perfectly caustic. But the application of this method to the
industrial production of carbonic acid or to the burning of lime has not heretofore
been realized. It is still customary to burn limestone, strontianite, dolumite, etc,
in kilns at an incipient white heat either feeding in solid fuel and air, or gas and
air; generally also where much carbonic acid is employed as in sugar manufactories,
ammonia soda manufactories and many other chemical works, carbonic acid is
produced in similar kilns provided with expensive pumping apparatus, by which
method of course no pure carbonic acid is obtained but only gaseous products of
combustion containing carbonic acid the proportion of which under the most
favourable circumstances does not exceed about 33 per cent of the entire volume,
at least two thirds of the said gases consisting of nitrogen, oxygen, carbonic oxide,
and smoke particles.

page_text: Fig being a vertical section through the middle of the furnace.
Fig 2 a plan of the furnace.
Fig 3 a horizontal section in line Ơ D; and
Fig 4 a horizontal section in line E F.
A is the double walled furnace. B B are the retorts. C is the cover of the
furnace and support for retorts. D D are hollow columns of the furnace serving
also as air heaters. E E annular gas supply pipes with connecting pipes in the
furnace. Ffresh air supply pipe: G conduit for supplying heated air to the
furnace. H discharge for the products of combustion, serving also to heat the
frosh-air. I pipo conducting steam. to_the_retorts. K collecting pipe with con-
nections to the retorts. L grates in the retorts M grate bearers. N bolts for the
__grate bearers. O and O¹ upper and lower retort covers.
The drawing represents a furnace with seven retorts, but it may well have 6, 9
or 12 retorts; their length will depend on the yield required, it may be 4 metres
instead of 3 metres in the fire. But it is deemed advantageous to construct them
with a clear diameter or width of 250 millimetres as being the most suitable. The
wider they are the more difficult is it to heat them through, and therefore the more
intense must be the heat of the gas fire burning around them, but it is desirable
for the preservation of the retorts that this heat be not unnecessarily high.
The furnace is not connected with any chimney and is therefore not dependent
on any chimney draught. The air and gas which it requires for heating purposes
are forced into it by means of a Root's blower. Supposing that for the heating
operation 1 kilo of coke bo required per minute, then the root's blower has to force
one half (4, cubic metres) of the air necessary for the complete combustion of
1 kilo of coke into the gas generator, and the other half (=4/, cubic metres) into
the furnace proper. The arrangement whereby that proper supply of air combined
with perfect regulation both as regards quantity and quality of the fire can be
attained is considered essential.
On leaving the generator the gas flows directly through two annular gas
supply pipes or rings and ten outlets therefrom (see drawing) into the furnace
at a temperature of from 500 to 600° Celsius,-the requisito air for the
combustion of this gas is forced into the furnace under the cover by means
of five nozzles so arranged that the inflowing currents of air shall not intersect
the inflowing currents of combustible gas, thus there is avoided the production
of any pointed flame such as would injure the retorts. The air before admission
to the furnace is heated to from 300° to 400° C. This previous heating
is effected within the five columns on which the furnace stands there being
utilized for this purpose the heat of the escaping products of combustion flowing
downwards through the said columns. Although with the described means all
conditions for the production of a comparatively very high temperature obtain yet
the mixing of the air and gas is gradual and extends throughout the height of the
furnace. As will be seen the beating is effected from above downwards.
From the construction and operation above referred to it results that the
furnace is heated equally throughout and not in any part oither excessively or
insufficiently.

page_text: As is seen in the drawing the retorts are only half filled with the lime-stone
or strontianite to be burnt and these are in pieces not exceeding from 20
to 40 millimetres.
For every 1000 kilos of the charge 1 kilo of steam is allowed to pass through
per minute. The steam first entering the empty parts of the retorts which are
very hot, and as it occupies about 15 seconds in passing the said parts it will at the
time of entering the charge have become superheated to such an extent that it
will readily decarbonise the mineral on the grate. The current of steam carries
the carbonic acid which has become liberated up to the outlet of the retorts and to
the condensors.
In such retorts about 4 hours are required for the complete removal of carbonic
acid from their contents. Then after isolating the retort by closing the cock at the
top the caustic mass is allowed to fall together with the moveable grate. After
again setting up the grate the retort is at once recharged from above through a
Morton door, which is readily handled and effects hermetic closing. In such
furnaces the vertical iron retorts must be suspended from the cover so that they
may be free to expand and contract.
The improved method of construction meets this requirement in an efficient
manner, and also allows of the easy renewal of the retorts.
Moreover, it is not necessary to give the retorts any protective coating of
refractory material such as clay or fire brick notwithstanding the high temperaturo
(equal to that of melting copper) to which they are constantly subjected. Care
must however be taken in casting them not to use common iron of low melting
point.
For the burning of each Centner (say 1 cwt) of Rudesdorf fossiliferous lime-stone
there may be employed 6 kilos of coke and 12 kilos of steam. From this it will
be seen how relatively small a quantity of fuel is necessary for such a furnace.
If the retort instead of being charged with lime-stone is charged with ordinary
pyrites (say about the size of walnuts) a complete desulphurisation of the pyrites
will take place together with a partial decomposition of the steam the sulpur
escaping as sulphuretted hydrogen whilst magnetic oxide of iron will remain in tho
retort together with any other constituents of the pyrites. Thus the furnace
serves also the purpose of cheaply producing sulphuretted hydrogen gas.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said William Lloyd Wise in the Patent Office on the 15th February
1884.
WILLIAM LLOYD WISE of 46 Lincoln's Inn Fields in the County of Middlesex
"IMPROVEMENTS IN THE MANUFACTURE OR PRODUCTION OF CARBONIC ACID FROM
THE CARBONATES OF CALCIUM, MAGNESIUM, STRONTIUM, AND BARIUM, AND
APPARATUS THEREFOR" (a communication from D Hubert Groüven a person
resident at Leipzig, Saxony, in the German Empire)
It is known that if through a red hot pipe filled with pieces of limestone,
dolomite, or strontianite superheated steam be passed, an evolution of carbonic
acid takes place even at a moderate red heat and after a certain time the minerals
in question become perfectly caustic. But the application of this method to the
industrial production of carbonic acid or to the burning of lime has not heretofore
been realized. It is still customary to burn limestone, strontianite, dolomite, etc..
in kilos at an incipient white heat either feeding in solid fuel and air or gas and
__nir.; generally also where much carbonic acid is employed as in sugar manufactories,
ammonia soda manufactories and many other chemical works, carbonic acid is
preduced in similar kilns provided with. expensive pumping apparatus, by which
inethod of course no pure carbonic acid is obtained but only gaseous products of
combustion containing carbonic acid the proportion of which under the most
favorable circunstances does not exceed about 33 per cent of the entire volume, at
least two thirds of the said gases consisting of nitrogen, oxygen, carbonic oxide,
and smoke particles.
Now the production of carbonic acid by means of steam has not only the
advantage of rendering it practicable to work at a lower temperature, but also, as
no gas of any kind becomes mixed with the evolved carbonic acid except readily
condensible excess steain, a carbonic acid results of 99% or thereabout, that is to
say, as pure as it is obtained in mineral water manufactories from magnesite and
sulphuric acid. The advantages of the steam method being so great and apparent,
its non-employment hitherto may be attributed to the difficulties attending the
construction of a suitable furnace apparatus, and which difficulties this invention is
designed to obviate or mitigate. And in order that the manner in which this is
effected may be clearly understood I proceed to describe the manner of carrying
to invention into practical effect with referenco to the accompanying drawings,
whereof,
Fig 1 is a vertical section through the middle of a furnace according to this
invention.
Fig 2 a plan of the furnace
Fig 3 a horizontal section in line C. D; and
Fig 4 a horizontal section in line E. F.
A is the double walled furnace, B. B are the retorts, C is the cover of the furnace
and serves also to support the retorts. D. D are hollow columns of the furnace
serving also as air heaters. E. E annular gas supply pipes with connecting pipes
in the furnace. F. fresh air supply pipe. G conduit for supplying heated air to
the furnace. H discharge for the products of combustion, serving also to heat the
fresh air. I pipe conducting steam to the retorts. K collecting pipe with
connections to the retorts. L grates in the retorts. M grate bearers. N bolts for
the grate bearers. On withdrawing these bolts the grates they support and the
charge of material upon the same will fall. O and 0¹ unner and lower retort

page_text: I
The drawing represents a furnace with seven retorts, but it may well have 5, 9,
or 12 retorts; their length will depend on the yield required, it may be 4 metres
instead of 3 metres in the fire. But it is deemed advantageous to construct them
with a clear diameter width of 250 millimetres as being the most suitable. Tho
wider they are the more difficult is it to heat them through, and therefore the more
intense must be the heat of the gas fire burning around them, but it is desirablo
for the preservation of the retorts that this heat be not unnecessarily high.
The furnace is not connected with any chimney and is therefore not dependont
on any chimney draught. The air and gas which it requires for heating purposes
are forced into it by means of a' Root's blower. Supposing that for the heating
operation 1 kilo of coke be required per minute then the Root's blower has to
force one half (= 4, cubic metres) of the air necessary for the complete combination
of 1 kilo of coke into the gas generator, and the other half (= 41, cubic metres)
into the furnace proper. The arrangement whereby that proper supply of air
combined with perfect regulation both as regards quantity and quality of the fire
can be attained is considered essential.
On leaving the generator the gas flows directly through two annular gas supply
pipes or rings and ten outlets therofrom (see drawing) into the furnace at a
temperature of from 500 to 600° Celsius: the requisite air for the combustion
of this gas is forced into the furnace under the cover by means of five nozzles so
arranged that the inflowing currents of air sball not intersect the inflowing currents
of combustible gas, thus there is avoided the production of any pointed flamo
such as would injure the retorts. The air before admission to the furnace is heated
to from 300° to 400° C. This previous heating is effected within the five columns
on which the furnace stands there being utilised for this purpose the heat of the
escaping products of combustion flowing downwards through the said columns.
Although with the described means all conditions for the production of a
comparatively very high temperature obtain yet the mixing of the air and gas
is gradual and extends throughout the height of the furnace. As will be seen the
heating is effected from above downwards.
From the construction and operation above referred to it results that the
furnace is heated equally throughout and not in any part either excessively or
insufficiently.
As is seen in the drawing the retorts are only half filled with the lime-
stone or strontianite to be burnt and these are in pieces not exceeding from
20 to 40 millimetres.
For every 1000 kilos of the charge 1 kilo of steam is allowed to pass through
per minute. The steam first entering the empty parts of the retorts which are very
hot, and as it occupies about 15 seconds in passing the said parts it will at the
time of entering the charge have become superheated to such an extent that it
will readily decarbonise the mineral on the grate. The current of steam carries
the carbonic acid which has become liberated up to the outlet of the retorts and.
to the condensors.
In such retorts about 4 hours are required for the complete removal of carbonic
acid from their contents. Then after isolating the retort by closing the cock at
the top the caustic mass is allowed to fall together with the moveable grate.
After again setting up the grate the retort is at once recharged from above through
a Morton door, which is readily handled and effects hermetic closing. In such
furnaces the vertical iron retorts must be suspended from the cover so that they
may be free to expand and contract.
The improved method of construction meets this requirement in an efficient
manner, and also allows of the easy renewal of the retorts.
Moreover, it is not necessary to give the retorts any protective coating of
refractory material such as clay or fire brick notwithstanding the high temperature
(equal to that of melting copper) to which they are constantly subjected. Care
must however be taken in casting them not to use common iron of low melting
point..

page_text: For the burning of each Centner (say 1 cwt) of Rudesdorf fossiliferous lime-
stone there may be employed 6 kilos of coke and 12 kilos of steam. From this it
will be seen how relatively small a quantity of fuel is necessary for such a
furnace.
If the retort instead of being charged with lime-stone is charged with ordinary
pyrites (say about the size of walnuts) a complete desulphurisation of the pyrites
will take place together with a partial decomposition of the steam the sulphur
escaping as sulphuretted hydrogen whilst magnetic oxide of iron will remain
in the retort together with any other constituents of the pyrites. Thus the
furnace serves also the purpose of cheaply producing sulphuretted hydrogen gas.
Having described the nature of the said invention and the manner of carrying
it into practical effect as communicated to me as aforesaid I hereby declare that
what is considered to be novel and original-and-is claimed as secured to me under
the Letters Patent first hereinabove in part recited is,―
1. The manufacture on a commercial scale of pure carbonic acid gas from the
carbonates of calcium, magnesium, strontium, and barium, in the improved manner
hereinabove described with reference to the accompanying drawings, producing
as bye-products oxide of calcium, oxide of magnesium, oxide of strontium, and
oxide of barium from the respective carbonates, as above set forth.
2. In a furnace for the purposes hereinabove set forth.
(a) Arranging the annular conduits for supplying combustible gas to the
combustion chamber substantially as described.
(b)-Causing-the-products_of_combustion to be discharged from the combustion
chamber through pipes arranged within hollow columns that serve to support
the furnace substantially as described.
(c) Causing the air that is to be used for supporting combustion in the
combustion chamber of the furnace to-be-heated on its way to that chamber.
by passing through the hollow columns that support the furnace and whilst
therein circulating around and in contact with the pipes whereby products of
combustion are discharged and the air thus heated to enter the combustion
chamber at its upper part above the gas inlets substantially as described.
(d) Arranging the vertical cast iron retorts to hang freely from the furnace
cover and to pass through stuffing boxes in the furnace floor substantially as
described.
(e) Providing in each retort a removeable grate forming in the retort a division
so that the part below the grate serves for superheating steam, and the part
above the grate for the reception of the materials to be treated by the
superheated steam substantially as described.
(f) The arrangement whereby the grate of each retort with its charge can be
lowered by the simple withdrawal of a bolt.
3. The improved furnace constructed arranged and operating as hereinabove
described and illustrated.
In Witness whereof I the said William Lloyd Wise have hereunto set my
band and seal this fifteenth day of February in the year of Our Lord one thousand
eight hundred and eighty four.
117 TTV
WTON