ntium, and the like, and Apparatus therefor.
Year: 1885

page_text: Strontium, and the like, and Apparatus therefor.
I, WILLIAM LLOYD WISE, of No 46 Lincoln's Inn Fields, in the County of
Middlesex, Consulting Engineer and Patent Agent, do hereby declare the nature
of said invention for "IMPROVEMENTS IN EFFECTING THE DECARBONATION OF
EARTHY CARBONATES SUCH AS CARBONATE OF BARIUM, CARBONATE OF STRONTIUM
AND THE LIKE AND APPARATUS THEREFOR" (a communication to me from abroad
by Raoul Radot, of Paris, France, Engineer) to be as follows:-
This invention relates to an improved method or process for the decarbonation
of earthy carbonates such as carbonate of barium, carbonate of strontium and the
like and apparatus therefor.
"
Heretofore the earthy carbonates have been generally decarbonated by mixing a
reducing agent such as carbon or a body containing carbon either in a solid or
liquid form with the carbonate and raising it to a high temperature.
It has also been proposed to effect the reduction in a current of superheated
steam or of a gaseous reducing agent such as hydrogen. But all these processes
offer considerable difficulties. When the material is mixed with the carbon it
combines with the impurities in the carbon which cannot be always easily.
removed. When steam is employed or the gaseous reducing agent it is necessary'
to produce and superheat it, entailing a large expenditure of fuel and necessitating
the use of complicated apparatus.
To obviate the above mentioned difficulties according to this invention, car-
bonated gaseous or reducing agents are substituted for the carbon the reducing
agent or steam being produced in the apparatus.
The following methods may be used for carrying the above principles into
practice.
1. The employment of a carburetted gas for heating the material which also acts
as a reducing agent.
2. The employment of a hydrogenated gas for beating the material the com-
bustion of which produces the superheated steam required to act as a reducing
agent.

page_text: 3. The employment of a hydrocarbonated gas or a mixture of carbonated and
hydrogenated gases for heating the material which act jointly as reducing and
heating agents.
4. The employment of any suitable combustible gas, which as it issues from a
burner, is mixed with steam, becoming thereby superheated within the apparatus.
The application of the above principles and the apparatus enabling them to be
carried into practice form the object of this invention.
The decarbonation with any of the above mentioned gases is carried on in an
apparatus or furnace which is essentially composed of a hearth A fed continuously.
from the upper part or chamber in which the material is placed. This hearth is
heated by the above mentioned gases mixed in suitable proportions with other
gases so as to render them combustible. These gases issue from one or more
tuyeres or gas burners B. The operation takes place in the hearth A and the
reduced material is removed through the lower opening C.
The apparatus as shewn in the accompanying drawing is worked in the following
manner.
The carbonate under treatment is introduced through the mouth E of the furnace
in which mouth is arranged an opening F for the escape of gases proceeding from
the hearth when it is desired to utilize them.
The carbonate descends into the chamber D in which it becomes gradually
heated by contact with the gases escaping from the hearth, and reaches subse-
quently the hearth A itself; spreading over it so as to form a slopo b and a free
space à which constitutes the combustion chamber.
The gases required for reducing and for heating purposes are caused to issue
(preferably under pressure) from one or several tuyeres or gas burners Ba
The combustion takes place in the chamber a and the products of combustion or
the unburnt gases act upon the surface of the slope b from which the material
gradually falls.
t
When the charge consists of carbonate of barium the product obtained is fluid
and can be run out like slag or cast iron is run out of a blast furnace.
When the charge consists of carbonate of strontium, the removal of the reduced
products is effected in the same manner as in ordinary lime kilns.
As the resulting products of the above operation may not be completely reduced
at once it is advisable to continue the action of the gases for a sufficient period of
time to ensure a more complete reduction.
When the material becomes Huid under the action of the first set of burners, it
may be maintained in such a state by means of a fresh series of burners, and the
reduction may be still further proceeded with.
When the material discharged from the orifice c is found to be incompletely
reduced, it must be lixiviated and the insoluble residuum or unreduced carbonate
must be subjected to a fresh treatment.
In order to facilitate the above described operation it may be desirable to add to
the carbonate a carbonated substance preferably liquid and as pure as possible, if
it is desired to obtain a pure product.

page_text: CarDomates, such as Carbonate Of Darium, Carbonate of
Strontium, and the like, and Apparatus therefor.
I, WILLIAM LLOYD WISE, of N° 46 Lincoln's Inn Fields, in the County of
Middlesex, Consulting Engineer and Patent Agent, do hereby declare the nature
of this invention (a communication to me from abroad by Raoul Radot, of Paris,
France, Engineer,) and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
This invention relates to an improved method or process for the decarbonation of
earthy carbonates such as carbonate of barium, carbonate of strontium and the like
and apparatus therefor.
Heretofore the earthy carbonates have been generally decarbonated by mixing
a reducing agent, such as carbon or a body containing carbon either in a solid
or liquid form with the carbonate and raising it to a high temperature.
It has also been proposed to effect the reduction in a current of superheated
steam or of a gaseous reducing agent such as hydrogen. But all these processes
offer considerable difficulties. When the material is mixed with the carbon it
combines with the impurities in the carbon which cannot be always easily removed.
When steam is employed as the gaseous reducing agent it is necessary to produce
and superheat it entailing a large expenditure of fuel and necessitating the use
of complicated apparatus.
To obviate the above-mentioned difficulties according to this invention, car-
bonated gaseous or reducing agents are substituted for the carbon the reducing
agent or steam being produced in the apparatus.
The following methods may be used for carrying the above principles into
practice.
1. The employment of a carbonated gas for heating the material which also acts
as a reducing agent.
2. The employment of a hydrogenated gas for heating the material the com-
bustion of which produces the superheated steam required to act as a reducing
agent.
3. The employment of a hydrocarbonated gas or a mixture of carbonated and
hydrogenated gases which act on the material as reducing and heating agents.
4. The employment of any suitable combustible gas which as it issues from
a buruer is mixed with steam becoming thereby superheated within the apparatus.
5. The employment of a liquid or solid hydrocarbon or of water gas to which.
steam may or may not be added.
The application of the above principles and the apparatus enabling them to be
carried into practice form the object of this invention.
The decarbonation with any of the above mentioned substances may be carried:
on in an apparatus or furnace which may be either of a deep or crucible type or of.
a shallow or reverberatory type analagous for instance to those employed for melting,

page_text: glass. I will first, by way of example, describe the case where a deep furnace is
employed an arrangement which is shewn in vertical section in Fig. 1 of the
accompanying drawing.
This furnace is essentially composed of a hearth A fed continuously from the
upper part or chamber D in which the material is placed. This hearth is heated
by the above-mentioned gases mixed in suitable proportions with other gases so as
to render them combustible. These gases issue from one or more tuyeres or gas
burners B. The operation takes place in the hearth A and the reduced material is
removed through the lower opening C.
"
The apparatus as shown in Fig. 1 is worked in the following manner:
The carbonate under treatment is introduced through the mouth E of the
furnace in which mouth is arranged an opening F for the escape of gases proceed-
ing from the hearth when it is desired to utilize them.
The carbonate descends into the chamber D in which it becomes gradually heated
by contact with the gases escaping from the hearth, and reaches subsequently the
hearth A itself and spreading over it so as to form a slope b, and to leave a
free space a which constitutes the combustion chamber. The gases required for
reducing and for heating purposes are caused to issue (preferably under pressure)
from one or several tuyeres or gas burners B.
L
The combustion takes place in the chamber a and the products of combustion
or the unburnt gases act upon the surface of the slope b from which the material
gradually falls.
When the charge consists of carbonate of barium the product obtained is fluid
and can be run out in the same way as slag or cast iron is run out of a blast
furnace.
As the resulting products of the above operation may not be completely reduced
at once it is advisable to continue the action of the gases for a sufficient period of
time to ensure a more complete reduction.
When the material becomes fluid under the action of the first set of burners, it
may be maintained in such a state by means of a fresh series of burners, and
the reduction may be still further proceeded with).
When the material discharged from the orifice c is found to be incompletely
reduced, it must be lixiviated and the insoluble residuum or unreduced carbonate
must be subjected to a fresh treatment.
In order to facilitate the above described operation it may be desirable to add to
the carbonate a carbonaceous substance preferably liquid and as pure as possible,
if it is desired to obtain a pure product.
When a shallow or reverberatory furnace is used, the arrangement shewn in
longitudinal and transverse section in Figs. 2 and 3 respectively may be employed.
In this case the furnace consists of a chamber C constructed of refractory material
which should be such as to be as little liable as possible to be attacked by the
decomposed product which may be composed of aluminous, magnesian or plumbago
blocks or pieces. This chamber is covered with an arch of very refractory material.
The gas or hydrocarbonated vapours arrive at A and burn by contact with the hot
air supplied from a recuperator in which the heat of the products of combustion and
of the flames of the furnace are utilized. These hydrocarbonated vapours may be
produced by the mechanical spraying of coal tar or petroleum under the influence
of air or steam under pressure. The vapours are conveyed to the sole or bed of
the furnace on which the material under treatment has been placed through an
opening B. The combustion of the gases or vapours causes the carbonate when
carbonate of barium is treated to melt first into a pasty mixture which gradually
becomes fluid and then runs out of the furnace through an opening suitably
arranged for that purpose. Instead of feeding the furnace with pure carbonate
such as issues from the filter-presses of sugar works, a small quantity of carbon or
carbonaceous material as pure as possible may be added thereto. Under its
influence decomposition takes place more rapidly and at a lower temperature than
would otherwise be the case but the decomposed product remains in a pasty state.

page_text: The action resulting from the combustion of hydrocarbonated or carbonated
gases mixed with steam in conjunction with the decomposing action of the carbon
inixed with the material treated and the high temperature easily reached by the
combustion of these gases or sprayed hydrocarbons in an atmosphere of hot air
proceeding from the recuperator, has the advantage that it renders necessary only
a small addition of carbon to the material treated, in contradistinction to the
processes hitherto employed, and thus obviates the necessity of adding an excess
of carbon to the decomposed material which excess cannot be easily separated
therefrom.
f.
J..
On the drawing the burners are shewn placed at the end of the furnace, the door
closing the opening used for feeding purposes being arranged at the side of the
same. The burners may however be arranged laterally in one or several places and
the door may be placed at the end or in any intermediate position. The heating of
the furnace may likewise be effected by any of the above mentioned gases or
mixture of gases or vapours.
With regard to carbonate of strontium an arrangement may be employed which
consists in principle:-(1st). Of a movable sole or bed impelled forward by a
continuous notion and having a speed regulated according to the time required for
the completion of the reaction. (2nd). Of an arch covering the said sole or bed and
carrying in one corner a feeding hopper, in another place a discharge, outlet or
apparatus and between the two an apparatus for the distribution of heating or
reducing agents, the distance between these various parts being such, that while
the sole or bed is in constant operation, the material is heated to a sufficient degree
whilst passing from the feeding hopper to the heating apparatus and as completely
decarbonated as possible, whilst passing from the heating apparatus to the discharge
outlet, economical conditions being duly taken into account.
It will be readily understood that this arrangement may be carried out either
by means of a sole or bed composed of sections to which a rectilinear motion
is imparted or by means of a circular sole or bed presenting sections thereof
successively to the various points of the covering arch which carries the feeding,
heating and reducing, and discharging apparatus.
A third arrangement consists of a vertical chamber opened at the top for feeding
purposes and closed at the bottom by a horizontal sole or bed having a continuous
forward motion for carrying the material away between its surface and the next
lower stratum of the chamber while the said material is being treated in an even
layer.
The heating apparatus should be placed in the most favorable point of and at a
suitable height in the chamber and should be situated upon one or several of its
walls.
In every case the gases resulting from the reaction may be utilized: 1st by
recuperating their caloric and utilizing it in a previous heating of the air required
by the heating apparatus. 2nd by taking advantage of their richness in carbonic
acid and utilizing them for carbonating purposes.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is,―
In the process of decarbonating earthy carbonates:-
1. The simultaneous production and use within the combustion chamber by the
total or partial decomposition of the gases or mixture of gases introduced, of
the various conditions and agents (such as temperature, steam, and reducing
elements) to effect the decarbonation necessary.
2. The use of gaseous carbonated bodies in lieu of carbon for treating the
carbonates, such carbonated bodies also acting as reducing agents by means of
their unburnt portions.
3. The use for heating the carbonates of a bydrogenated gas which by its
combustion produces steam at a high temperature that acts as a reducing agent,

page_text: 4. The use for heating the carbonates of a hydrocarbonated gas or a mixture of
carbonated and hydrogenated gases which effect by their joint action the heating
and the reduction.
. 5. The use for heating and reducing the carbonates of liquid or solid hydro-
carbons with or without steam.
6. The superheating of steam within the combustion chamber by the combustion
of any suitable heating gas.
7. The use for the purpose set forth of apparatus substantially as hereinȧbove
described with reference to the drawings.