Improved Evaporating Apparatus.
Year: 1896

page_text: ONAL
TION
Improved Evaporating Apparatus.
1, ROBERT HUGH FORSYTHE FINLAY of Victoria Square in the City of
Belfast and County of Antrim in Ireland, Soap and Candle Manufacturer do
bereby declare the nature of this invention to be as follows:-
My invention relates to evaporating apparatus in which solids are deposited
during evaporation, and to the removal of such solids from the apparatus without
stopping or retarding the evaporation.
1
For this purpose I attach an airtight chamber to the bottom of a vacuum pan,
and I provide a valve to open and close the communication between them.
I separate the lower part of the chamber from the upper part by a perforated
plate or other suitable porous partition.
The upper part of the chamber receives the deposits, and I provide it with a
door through which they may be removed. The lower part is connected with the
vacuum pan by a pipe through which any liquid may be withdrawn, and I may
expel any liquid from about the deposits by steam.
I also provide the chamber with a pipe or other means by which it may be filled
with liquor such as is being evaporated in the vacuum pan.
Dated this 25th day of July 1896.
HUGH
HYNDMAN,
6 Chichester Street, Belfast, Agent for Applicant.
I, ROBERT HUGH FORSYTHE FINLAY of Victoria Square in the City of
Belfast and County of Antrim in Ireland, Soap and Candle Manufacturer 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:-
My invention relates to evaporating apparatus in which solids are deposited
during evaporation, and to the removal of such solids from the apparatus without
stopping or retarding the evaporation.
For this purpose I attach an airtight filter chamber to the bottom of a vacuum
pan, and I connect them by a flanged valve or cock which provides a passage between
them for the solids to fall through; and I separate the lower part of the filter
chamber from the upper part by a perforated plate or other suitable porous partition,
and provide a door in upper part thereof through which the deposits therein from
the vacuum pan may be removed, substantially as set forth in the Specification of
Wells' evaporating apparatus patented No. 5124, A.D. 1887. But I prefer to
employ a simple valve or cock to open and close the communication between the

page_text: vacuum pan and the filter chamber instead of a sluice valve which is liable to be
clogged by the precipitated salts, and to allow air to pass.
At the top of the filter chamber or between the stopper and the lower flange of
the valve or cock 1 provide an air-valve for the expulsion of air from the filter
chamber while liquor is flowing into it from a cistern as presently described,
which air-valve also serves for the admission of air when the solids are being
drained.
A valved pipe issuing from the bottom of the lower part of the filter chamber
connects it with the upper part of the vacuum pan and provides means for the
withdrawal of any fluid passing through the perforated plate or other porous
partition as heretofore practised; and to the pipe and rose shewn in Wells'
evaporating apparatus for introducing water for washing the deposits I add a
valved pipe leading from a boiler or exhaust pipe by the aid of which I may more
effectually remove any liquid from about the deposits with a current of steam.
I dispense with a sight glass in the lower part of the filter chamber as shewn in
Wells' evaporating apparatus and am thereby enabled to considerably reduce
its size.
also dispense with the catch pots placed by him in the pipes provided for the
escape of vapour from the top of the evaporators and obviate the liability to prime
due to the air from the filter chamber passing through the vacuum pan or evaporator
as presently explained.
But what I claim as a special feature in my invention is the arrangement for
providing the filter chamber with means by which it may be filled directly and not
through the vacuum pan with liquor such as is being evaporated, and by which
I escape from drawbacks connected with Wells' said evaporating apparatus, and
obtain several important advantages, including increased evaporation. The chief
drawbacks I refer to arise from the suction of the air from the filter chamber into
and through the vacuum pan, in which case such air expanding quickly will be
liable to carry a quantity of the liquor in the vacuum pan along with it through
the vapour pipe at the top; from the access of such air into the vacuum pan,
resulting in the reduction of the vacuum and the interruption of evaporation; from
the lowering of level of the liquor in the vacuum pan and raising it again by the
addition of comparatively cold liquor from the reservoir, thereby retarding the
boiling aud evaporation, as well as from many other causes.
The means I provide against such disadvantages consist in the use of a valved
pipe leading from the reservoir of liquor to be evaporated direct to the filter
chamber which I thereby fill with such liquor as soon as the deposits have been
removed from it and the door and the valves of the other pipes and tubes connected
with it, except the air-valve, have been closed.
There are several ways by which the filling of such filter chamber with the
liquor can be regulated; for instance, by providing an independent or second cistern
to contain the quantity requisite for filling it, or by furnishing a sight glass at the
upper portion of it, or by simply allowing the liquor to enter until it overflows through
the air-valve.
And in order that my said invention may be more fully understood I shall now
refer to the front elevation drawing hereunto annexed, showing a vacuum pan and
filter chamber connected together by a flanged cock which provides a passage
between them for the solid deposits; a perforated plate separating the upper from
the under part of the filter chamber, and the door in the upper part through which
the solid deposits may be removed; a valved pipe connecting the lower part of the
filter chamber with the vacuum pan; an air-valve for the expulsion and admission
of air, and a cistern and pipe with valved branches leading from it and both
communicating with the vacuum pan and the upper part of the filter chamber; also
a water and steam pipe to the rose within the filter cistern; and a vapour pipe at
the top of the vacuum pan.
A is the vacuum pau; B is the flanged cock connecting the vacuum pan with C,
the upper part of the filter chamber; 1 is the door through which the solid deposits

page_text: are removed; E is the perforated plate separating the upper part, C, of the filter
chamber from F, the lower part thereof, and on which the solids are deposited;
G is the air-valve through which air is expelled from or admitted to the filter
chamber; H and J are pipes through which steam and water respectively are
conveyed to the rose within the filter chamber; K is the valved pipe issuing from
the bottom of the filter chamber and connecting it with the upper part of the
vacuum pan; L is a cistern for storing the liquor to be evaporated, and having a
pipe with valved branches, M and N, leading into the upper parts of the vacuum
pan, A, and filter chamber, C, respectively.
I will now describe the operation of charging and discharging the filter chamber, C,
in order to shew the operation of my improved apparatus. The chamber having
been emptied from a preceding charge I first close the door, D. Next I open the
air-valve, G, and thereupon I open the valve in the supply pipe, N. The liquor
from the cistern thereupon fills the filter chamber displacing the air which escapes
through the air-valve, G. When the escape of a little liquor through the air-cock
shews that the air in the chamber has been completely displaced I close the valve
in the supply pipe, N, and also the air valve, G. Thereupon I open the flanged
cock, B, between the vacuum pan and the filter chainber thus permitting the solids
deposited in the bottom of the vacuum pan to esape into the filter chamber. In
so doing they displace more or less of the liquor with which the filter chamber has
been filled, but as this liquor consists of the same material as that which is being
treated in the vacuum pan, A, it does not occasion any inconvenience in the carrying
on of the evaporating operation. When the charge of deposited solids has entere
the filter chamber I close the cock, B, and open the air-valve, G. I next open the
valve in the pipe K which establishes communication between the upper part of
the vacuum pan and the bottom of the filter chamber. Through this communicating
tube the liquid from the filter chamber is drawn off and the deposited solids are
left upon the perforated plate, E. Next by opening the valves in the pipes H
and J, I cause water or steam or water and steam as the case may be to pass into
the filter chamber and to be drawn through the deposited solids thus washing them
and finally displacing the liquid by means of the steam, but the use of these valves
may sometimes be dispensed with. When the deposits have in this way been
brought into the required condition I first shut off the supply of steam and water.
I then close the valve in the pipe K and the chamber now being completely shut off
I am able to open the door, D, and withdraw the deposited solids. When that is
done the filter chamber is ready for another like operation.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I would have it to be
understood that I do not claim as of my invention or the exclusive use of a filter
chamber and air valve, nor of a flanged valve or cock, or valved pipes, or a rose,
except when the same are constructed and employed in the manner and for the
purposes which I have described, nor do I claim the use of a vacuum pan or any
of the separate mechanical parts which constitute my improved evaporating
apparatus, but I declare that I claim
The combination (with or without the steam pipe, H) constituting my improved
evaporating apparatus constructed and employed substantially in the manner and
for the purposes herein before described and illustrated by the drawing hereunto
annexed.
HUGH
HYNDMAN,
6 Chichester Street, Belfast, Agent for Applicaut.