Improvements in Multiple Evaporating Apparatus.
Year: 1890

page_text: Date of Application, 14th Oct., 1890
Complete Specification Left, 14th July, 1891-Accepted, 10th Oct., 18º1
PROVISIONAL SPECIFICATION.
Improvements in Multiple Evaporating Apparatus.
I THOMAS SLAITER Mechanical Engineer of 20 Eastbank Stamford Hill
Stoke Newington London do hereby declare the nature of this invention to be as
follows:-
The object of my invention is to evaporate and concentrate fluids by passing
the said fluids over and through pipes heated by steam or other heating medium,
such pipes with their steam supplying passages being contained in open tubes
or channels fixed in a series of vessels or effects in which a vacuum is maintained
by means of an air pump and forming a multiple effect combination-the mode of
construction being as follows-In a long vessel of cylindrical or other form
consisting of a large central vacuum chamber with a steam or vapour chamber at
one end and condensed water chamber at the other end, I insert a number of large
readily removeable tubes open at the top to the vacuum chamber, or arrange a
series of large open channels in the vacuum chamber. In each of these open tubes
or channels, place one or more pipes secured to the steam chamber end of the
vessel. Each of these pipes encircles another pipe with an annular space between
the two and these lie along and nearly at the bottom of the open tubes or channels.
At the steam chamber end of the vessel the annular space between the pipes is
open for the admission of steam or other heating medium but is closed at the
other end, this end of the inner pipe being open for the admission of fluid. These
pipes thus serve to heat any fluid in the channel that may surround or pass through
them. I further increase the heating surface by means of additional pipes in the
open tubes or channels the ends of the said pipes being open to the steam and
condensed water ends of the vessels, but these additional pipes are not provided
with inner pipes for the return of the fluid under treatment.
The fluid to be concentrated is admitted into the uppermost tubes or channels of
the first vessel or effect and after traversing their lengths is returned by way of
the inner pipes of the annular steam spaces and then by means of removeable bent
elbows is passed into the next lower channel where the process is repeated and so
throughout the series. Or the fluid may first pass through the inner pipes and
return by way of the open tubes or channels.
Dated this 14th day of October 1890.
THOMAS SLAITER.
COMPLETE SPECIFICATION.
Improvements in Multiple Evaporating Apparatus.
1, THOMAS SLAITER of 26 Eastbank, Stamford Hill, London, Mechanical
Engineer, 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:-
This invention has for its object evaporating apparatus of the same class as those.
described in the Specification of former l'atents granted to me No. 10493 in the
year 1888 and No. 34 in the year 1889.
In order to render such apparatus more efficient in action and more easy of
construction I form and arrange the parts in the following manner- -Each
apparatus consists of an outer shell, preferably cylindrical; it has flanged covers
at the ends bolted on. An air pump maintains a partial vacuum within this
enclosure. The end covers are made hollow, one receives the steam or vapour
D111

page_text: which is the heating medium and the other the water resulting from the
condensation of this steam or vapour which is conducted away.
Each cover also has a series of sockets open through it from front to back.
These open sockets are to receive evaporating troughs in which the liquid under
reatment is exposed and through which it flows. The trough is cylindrical at
the ends where it is contained in the open socket of the cover but it is uncovered
at the top for the remainder of its length where it extends along the vessel between
the front and the back covers.
In the cylindrical part of the trough at either end there is a hole and a facing
with an india rubber packing ring around the hole.
Within the open sockets of the covers are corresponding holes and faces, and
by these holes the steam or vapour passes out from the cavity of one cover plate
to be collected as water in the cavity of the other.
Within the trough there is a tube passing from end to end which conveys the
steam or vapour, it in turn is provided with facings and packing rings which
make tight joints against the bottom of the trough around the holes therein. So
there is, through the steam tubes free communication established between the
cavity in one cover and that in the other. The joints are rendered tight by
downward pressure exerted by screws applied on the upper sides of the steam tube.
The liquid in the trough is, in contact with the exterior surface of the steam tube
all around and the whole of this surface is available for the transmission of heat
to the liquid.
Each trough is closed at its ends by caps and ring packings which are compressed
around the cylindrical end of the trough between the cap and the outer face of the
cover. The cap at one end is plain but that at the other end has two openings
through it, the one is the inlet and the other is the outlet for the liquor. The
liquor on entering flows along the trough to the other end, it then enters a return
pipe which is contained within the steam tube and traverses it from end to end.
The steam tube and the return pipe are fixed together, by means of metal end
pieces which fill the interspace for a short distance at either end. Suitable
nozzle pieces are attached to the end pieces by screws. The nozzle piece at one
end serves to prevent the entrance of the liquor into the return pipe until it has
risen to a suitable level in the trough; at the other end the nozzle piece passes
out through the cap to conduct away the liquor. Both the nozzle pieces are so
formed as to allow vapour generated in the return pipe to escape freely. The
liquor passing out of one trough is caused to enter the next and so on from top to
bottom of the apparatus. Each trough with its steam tube and return pipe, caps
and other parts as above described constitutes an evaporator. The liquor first
enters the uppermost evaporator and descends progressively from one to another
until it reaches a receiving chamber at the lower part of the front cover.
The conveyance of the liquor from one evaporating trough to another is
effected by an elbow pipe held in place by a nut upon a screw stem projecting out
from the face of the cover. The elbow pipe has a socket at one end to receive
the extremity of the delivery nozzle and a tight joint is made by a packing ring
surrounding the nozzle and compressed against the face of the cap by the end of
the elbow pipe. Similarly the other end of the elbow pipe makes a tight joint at
the inlet on the cap of the next trough in the series.
The
These apparatus are arranged for multiple effect the vapour generated in the
first vessel is employed as the heating medium in the next vessel and so on.
water resulting from condensation is drawn off or pumped away.
In order that my said invention may be fully understood and readily carried into
effect I will proceed to describe the drawings hereunto annexed.

page_text: Figure 2 is a longitudinal section of one of the vessels.
Figure 3 is a longitudinal section on a large scale showing part of three of the
evaporators and portions also of the end covers.
Figure 4 is a transverse section of one of the evaporators taken through the
part which lies within the open socket in the cover; the walls of the socket are
also shown.
Figure 5 is a transverse section of one of the evaporators taken any where at a
distance from the cylindrical end.
Figures 6, 7 and 8 are transverse sections and show other forms which may be
given to the evaporators in their intermediate parts.
Figure 9 is an end view of the evaporator with the cap removed; at this end
the liquor enters and leaves the apparatus.
Figure 10 is another end view of the evaporator with the cap removed; this
end communicates with the condensed water chamber.
Figure 11 shows a method of securing the closing caps at the condensed water
chamber end of the evaporators.
A is the vacuum chamber within the casing.
B the steam or heated vapour chamber within the cover at one end thereof.
C the condensed water chamber within the cover at the other end.
D are the open sockets in the covers at the ends of the vessels in which the
evaporators rest. The lower part of these sockets have holes O O for the
admission of steam to the evaporators and the egress of condensed water.
E is the receiving chamber in the cover for receiving the liquor after passing
along the various channels and pipes.
F are the troughs of the evaporator in which the liquor is heated and
evaporated.
These troughs are cylindrical at each end where they pass through the open
sockets in the covers.
Gare the caps closing the ends of the evaporators at the steam chamber end,
they compress elastic packing rings G'around the ends of the evaporators.
Hare the caps closing the evaporators at the condensed water end of the
vessel.
I are the steam tubes within the evaporating troughs; they may be semi-
cylindrical or of other form. They are readily removeable from the evaporating
troughs.
I are the steam spaces within the pipes I.
Jare the return pipes; they are fixed in the steam spaces of the steam tubes.
K are filling pieces at the ends that close the space between the steam tube I
and the return pipe J.
Lare seats formed around holes on the underside of the evaporating troughs F.
L'are similar seats formed around holes on the undersides of the steam tube I.
The seats under the steam tube rest in the seats under the evaporating troughs
and these in turn rest upon seats around the holes within the open sockets in the
covers; at each joint an elastic ring packing is provided.
M are cross bars lying on the upper surfaces of steam tubes I at each end.
Nare screws which pressing against the upper part of the open sockets and
pressing also on the cross bars lying on upper parts of steam tubes I hold the
seatings together.
O are holes in the bottoms of the open socket for the admission of steam.
O are holes for the release of condensed water at the other end.
Pare fixings on the steam tubes and return pipes at the steam chamber end of
the evaporators; they have nozzles P projecting through the closing cap G for
the passage of the liquor and P2 an uptake open to the vacuum space A for the
egress of vapour generated in the return tube.
Qare fixings at the condensed water end of the evaporating tubes. This is
open at the top to allow the liquor to flow in, and has a partition to prevent

page_text: any sudden return rush of the liquor in the return pipe and Q an uptake open to
the vacuum space A for the egress of vapour.
Rare bent elbows connecting the nozzles P of the return pipes with the
entrance nozzle upon the cap G of the next lower evaporator. These bent elbows
are pressed against the nozzles with intermediate elastic rings by means of a
central bolt as shown or otherwise.
At the condensed water chamber end the caps may be secured by tripod frames
as shown in Figure 11 or in any other approved way.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed declare that what I
claim is:
―:
1. An evaporating apparatus substantially as described and having a casing with
hollow covers at its ends, and open sockets in the covers; and also having trough
like evaporators with steam tubes and with liquor inlets and outlets such
evaporators being inserted into the open sockets of the covers, and the arrange-
ment also being such that the steam tubes serve to connect the cavity in one cover
with that in the other, the passage in each case being by corresponding holes in
abutting surfaces, one surface being within the open socket and the other upon
the portion of the trough evaporator which enters the socket.
2. In evaporating apparatus substantially as herein described having a casing
closed at the ends by covers and trough like evaporators contained in open sockets
in the covers the means herein set forth for closing the ends of the troughs,
providing the connections for the passage of the liquor from trough to trough and
for rendering the joints air-tight that is to say, providing caps G cach with an
inlet and an outlet through the latter of which the nozzle P protrudes and elbow
pipes R R extending from outlet to inlet and suitable joint surfaces and packing
rings and screws and nuts or equivalent means for drawing the parts together.
3. In evaporating apparatus substantially as described and in which the liquor
to be evaporated is caused to flow along a trough in contact with a steam tube
within the trough and then to return to the entrance end of the trough by a return
pipe contained within the steam tube; the arrangement of the parts as herein
set forth so that the liquor is in contact with the steam tube all around its periphery,
the whole of the exterior surface of the steam tube being thus rendered available
for the transference of heat to the liquor.
4. Evaporating apparatus substantially as represented by the annexed drawings.
Dated this 13th day of July 1891.
THOMAS SLAITER.