Year: 1873

page_text: Sealed the 20th June 1873, and dated the 4th January 1873.

page_text: trays or chambers, and in overflowing that tray or chamber be received
into another tray or chamber, and from that pass to another, and so on
until it arrives at the lowest, which is that subject to the greatest
amount of heat. The heat then passing from the first to the others
in succession until that which first received the liquor to be treated 5
receives the least of it.
I form the lower tray or chamber to in part surround the fire, the
fuel for which is supported on bars with an entrance for feeding by a
doorway formed through one side or surface of such lower chamber.
This doorway is capable of being closed tightly by luting or otherwise 1
after the supply of each charge of fuel, so that air to support com.
bustion may alone pass through the fuel. The part of this lower
chamber over the fire has a channel formed through it to conduct the
heat from the fire to the tray next above that first one, and I find it
convenient to allow the heat to pass through the first chamber at about 1
the centre of it to the under side of the centre of the second, in order
that such heat may then radiate over the surface of the liquor in the
first chamber under the surface of the second tray, and thence rise up
around the outer surface of that second tray to act on the surface of the
liquid in that tray and on the under side of a third tray, through which 2
I form a channel at or near the middle of it for the passage of the heat
to the upper surface of the liquor in that third tray and to the under
side of the tray next above, and so on, an arrangement which I find
convenient both for the overflow of the liquid from one tray to the next
below, and also for the progressive action of the heat from one to the 2
next above, but which may be varied, the object being that the liquor
whilst being operated upon may be supported in thin or
comparatively
thin layers, and that the heat may progressively act on it in the
successive layers, first on the under side of each tray or chamber and
then on the surface of the liquor therein. The whole is enclosed and 30
the vapour, the result of the distillation or condensation, is conducted
away by a pipe from the uppermost part. The matters remaining in
the lowest chamber may be withdrawn by taps or valves as desired.
In all cases of the vapour obtained having to pass through other
passing ammoniacal vapour through or in contact with sulphuric acid
matters, by which it becomes subject to pressure or resistance, as when &
in the manufacture of sulphate of ammonia, I obtain the required

page_text: 8, &c.
current to the atmospheric air by forcing it through the fuel from the
under side thereof, the fire being in a close chamber. Such flow may
however be obtained by a vacuum applied to the outlet passage.
10
5
vers Patent,
filed by the said Alexander Angus Croll in the Great Seal Patent
Office on the 4th July 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALEXANDER
ANGUS CROLL, of Coleman Street, in the City of London, Civil Engineer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fouth day of January, in the
year of our Lord One thousand eight hundred and seventy-three, in
the thirty-sixth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Alexander Angus Croll,
5 Her special license that I, the said Alexander Angus Croll, my
executors, administrators, and assigns, or such others as I, the
said Alexander Angus Croll, my executors, administrators, and 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 IN MEANS OR APPARATUS FOR THE
DISTILLATION OF AMMONIACAL LIQUORS, WHICH IMPROVEMENTS ARE ALSO APPLICABLE
IN THE DISTILLATION OF OTHER LIQUIDS AND IN THE CONCENTRATION OF SOLUBLE
SALTS," upon the condition (amongst others) that I, the said Alexander
Angus Croll, my executors or administrators, by an instrument in writing
under my, or their, or one of their hands and seals, should particularly
describe and ascertain the nature of the said Invention, and in what
) in the Great Seal Patent Office within six calendar months next and
manner the same was to be performed, and cause the same to be filed
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Alexander Angus Croll, do hereby
declare the nature of the said Invention, and in what manner the same is

page_text: to bo performed, to be particularly described and ascertained in and by
the following statement thereof, that is to say :-
the liquid
matters to be acted upon are received into one of a series of evaporating
trays or shelves, and in overflowing that tray or shelf be received into
another tray or shelf, and from that pass to another, and so on until it
arrives at the lowest, which is that subject to the greatest amount of
heat. The heat then passing from the first to the others in succession
until that which first received the liquor to be treated receives the least
heat.
I form the lower tray or chamber to in part surround the fire, the
fuel for which is supported on bars with an entrance for feeding by a
doorway formed through one side or surface of such lower chamber.
This doorway is capable of being closed tightly by luting or otherwise
after the supply of each charge of fuel. The part of this lower chamber
over the fire has a channel formed through it to conduct the heat from
the fire to the tray next above that first one, and I find it convenient to
allow the heat to pass through the first chamber at about the centre of
it to the under side of the centre of the second, in order that such heat
may then radiate over the surface of the liquor in the first chamber
under the surface of the second tray, and thence rise up around the
outer surface of that second tray to act on the surface of the liquid in
that tray, and on the under side of a third tray, through which I form
a channel at or near the middle of it for the passage of the heat to the
upper surface of the liquor in that third tray, and to the under side of
the tray next above, and so on, an arrangement which I find convenient
both for the overflow of the liquid, from one tray to the next below, and
also for the progressive action of the heat from one to the next above,
but which may be varied, the object being that the liquor whilst being
operated upon may be supported in thin or comparatively thin layers or
surfaces, and that the heat may progressively act on it in the successive
layers, first on the under side of each tray or chamber and then on the
surface of the liquor therein. The whole is enclosed and the vapour,
the result of the distillation, is conducted away by a pipe from the
uppermost part. The matters remaining in the lowest chamber may
be withdrawn by taps or valves as desired.
1

page_text: &c.
In all cases, of the vapour obtained having to pass through other
matters, by which it becomes subject to pressure or resistance, as when
passing ammoniacal vapour through or in contact with sulphuric acid
in the manufacture of sulphate of ammonia, I obtain the required
current to the atmospheric air by forcing it through the fuel from the
under side thereof, the fire being in a close chamber. Such flow may
however be obtained by a vacuum applied to the outlet nassece
DESCRIPTION OF THE DRAWING,
which shows a vertical section of apparatus arranged according to my
Invention. a, a, is the outer case of it; b and c are the alternate trays
or shelves for the liquid to be heated and vaporized; and d is the
6 receiver, into which the liquid ultimately falls after passing into and
from the successive trays b and c; and it will be seen that this receiver
surrounds the furnace or fire-box e, so that the heat generated by the
fuel in this fire-place acts directly on the surrounding surface of the
chamber d to effect the evaporation of the fluid therein.
h
D It will be seen that the trays c are somewhat smaller in diameter
than the interior of the case a, so as to allow of a free passage fall round
them, and they are held in position by suitable stays. The trays 6 on
the contrary fit closely on their outer diameter to the inside of the case a,
but are each provided with a passage g through the centre of them.
Each of the trays b and c is also provided with a rim b' or c', though
such rim is not in all cases necessary, the rim being used to admit of
the trays holding a small quantity or film of liquid. The liquid to be
acted upon is supplied in a continuous stream by a pipe / to near the
centre of the upper tray c, and as that tray fills or becomes covered the
liquid flows over the surrounding edge of it by the passage finto the
tray 6 next below it, from which it flows over the rim b' by the central
opening g, through it to the next tray c below it, and so on; it flows from
tray to tray until it arrives at the lowermost tray c, from which it flows
into the receiver d surrounding the fire-placo e, and is allowed to flow
out therefrom in regulated quantity by the passage i, whilst at the same
time the heat and products of combustion rising in the chamber e pass

page_text: out therefrom by the neck e¹ to the under side of the lowermost tray c,
and having traversed the under side of this tray radially such heat and
products of combustion pass up the passage f over the surface of the
liquid in that tray c, and under the lowermost tray b to the centre of
that tray b, whence they pass up through the opening g therein to 5
traverse over the surface of the liquid in that tray b, and under the next
tray c to the next passage f, and so on until such heat passes to the
In doing so the liquid in the respective
trays b and c is progressively heated, and evaporation therefrom takes
place, the lowermost trays or receivers receiving the greatest amount of 10
heat, and the uppermost, which first receive the liquor to be treated,
upper part of the chamber a.
receiving the least heat.
When distilling liquids giving off volatile bodies, as in the case of
treating ammoniacal liquors and other matters, I apply a close cover a
to the chamber a, and the volatile product is conducted away by a pipej 15
to a suitable receiver or condenser, and to aid the flow of the vapours
as well as the action of the heat I form the ash-pit a closed, closing
tightly both the door thereto and that to the fire-place e, and I force
currents of air therein by a force pump or other suitable means through
a pipe k perforated at the part within the ash-pit a², so as to distribute 20
the air supplied, thereby forcing it through the fuel on the bars of the
grate in the fire-place e, or the flow of air and matters may be obtained
by a vacuum applied to the outlet. I also apply a passage for the
admission of air in regulated quantities over the fire, and also a passage
with a mica or other suitable cover through which to watch the con- 25
dition of the fuel during combustion, and thereby regulate the quantity
of air so supplied over the fuel to the quantity of inflammable gases
manifest over the fire.
When treating ammoniacal liquors by means such as described the
flow from the chamber d by the pipe i will be regulated in relation to 30
supply and the absence of ammonia from the liquid so flowing.
answer well in carrying the same into effect, I would have it understood
Having thus described my Invention, and means which I find to
that I do not confine myself to the precise details given, as the same
may be varied without departing from the peculiar character of the 35
Invention, but what I do claim is, the arranging and combining r
for the distillation of ammoniacal and other liquids or the concentration
means

page_text: of soluble salts, by which the liquid under operation is continually
flowing in thin layers in one direction, whilst the heat and products of
combustion from the furnace employed are caused to flow in the opposite
direction amongst and taking with them the vapours and gases
5 obtained, substantially as described.
In witness whereof, I, the said Alexander Angus Croll, have here-
unto set my hand and seal, this Third day of July, in the
year of our Lord One thousand eight hundred and seventy-