Improvements in Apparatus for Evaporating, Concentrating, and Distilling Liquids.
Year: 1888

page_text: Date of Application, 6th Dec., 1888
Complete Specification Left, 29th Mar, 1889
Complete Specification Accepted, 11th May, 1889
Improvements in Apparatus for Evaporating, Concentrating, and
Distilling Liquids.
We, WILLIAM RENNY WATSON and ROBERT ANDREW ROBERTSON both of
45 Scotland Street, Glasgow, in the Counties of Lanark and Renfrew, North Britain,
Engineers do hereby declare the nature of this invention to be as follows:-
:-
This Invention relates to tubular evaporating apparatus, in which the vaporization
is effected during the flow of liquid in limited and regulated quantity through annular
passages between outer tubes and inner heating tubes or connected series of such
outer and inner tubes or coils in a single or multiple effect apparatus, and in which
the hot vapor or steam in a multiple effect apparatus which is separated from partially
concentrated liquid in one chamber, is utilized for heating a successive set of tubes or
coils throughout the series in use.
In the apparatus constituting this Invention the steam heating tubes are passed
longitudinally through the evaporating tubes, the object being to provide for better
concentrating liquids containing salts in solution and provide for readily removing
the heating tubes for cleaning them, by removal of salts or other matter deposited on
their outer surfaces.
The evaporators, when connected in multiple effect form, are arranged in vertical
series and the different chambers, flues and passages for supplying steam and liquid to
the tubes and for connecting the different series of coils, aro formed within the walls
of the apparatus and are of the simplest construction and arrangement, preferably in
the form of castings which are joined together, one above the other, by flanges and
bolts or rivets.
A single evaporator constructed in accordance with this Invention, with a separating
chamber, cellular liquid circulating chambers and connected vaporizing tubes, steam
boxes and connecting heating tubes passing through the vaporizing tubes, may be
D

page_text: operated alone with good results. It is therefore explained that this Invention is not
confined to a multiple effect apparatus, though the arrangement of steam flues and
boxes and of liquid ports favor the connection of two or more evaporators in vertical
series for operation and use as a multiple effect apparatus.
Dated the FIR den
ambar 1000
ST. JOHN V. DAY,
115, St. Vincent Street, Glasgow,
Petitioner's Agent.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Evaporating, Concentrating, and
Distilling Liquids.
We, WILLIAM RENNY WATSON and ROBERT ANDREW ROBERTSON both of
45 Scotland Street, Glasgow, in the Counties of Lanark and Renfrew, North Britain,
Engineers 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 :-
Our Invention relates to a novel arrangement of vacuum apparatus for evaporating,
concentrating and distilling liquids and wherein the evaporation, concentration or
distillation is effected during the flow of the liquid in limited and regulated quantity
through annular passages contained between outer tubes and inner tubes passing
through them.
It is explained that the construction of the apparatus is not altered, whether used
as an apparatus for concentrating, that is to say, increasing the density of the liquid
passed through it, or where used as a distilling apparatus, for either concentration or
distillation is effected by the process or operation of evaporation.
When used for concentrating a liquid, the object may be to effect concentration
only, or to both concentrate the liquid, as well as to collect the vapour given off, by
passing it into a condenser; or when such vapor is of no value, then the object may
be to concentrate the liquid without collecting the vapor which in such cases may be
allowed to escape.
When used for distilling a liquid, the object may be to effect distillation only, with
or without collecting the concentrated portion of the liquid, accordingly as it is, or is
not, of commercial value. In either case the vapor given off is collected by being
passed into or through a condenser.

page_text: As an instance of using our apparatus for distilling, we may mention its applica-
bility for producing fresh water on board ship, or elsewhere, from sea-water.
In this case the object is to collect the water of condensation and to allow the
concentrated brine to pass off as a waste product. In such case, the fresh water is
collected in the condenser after the vapor from which it has been condensed has given
up heat in effecting the concentration of the sea-water in the apparatus, and the brine
is discharged as a waste product.
The object of our improvements is principally to provide for the treatment of
liquids containing substances in solution which are precipitated during concentration
as these substances are found to adhere to the heating surfaces of concentrating and
distilling apparatus and in accomplishing this object such apparatus are at same time
rendered more portable.
he
By employing the present improvements such evaporating, concentrating or
distilling apparatus are constructed so that the liquid under treatment flows in
regulated and limited quantity through annular spaces between the internal surfaces
of containing tubes and the external surfaces of internal heating tubes by which
arrangement deposit which would otherwise impair the efficiency of the apparatus is
deposited upon the external surfaces of the heating tubes from whence on the said
heating tubes being withdrawn as hereinafter provided for the deposit may
removed by scraping or otherwise more readily than from the internal surfaces of
similar tubes. Also by varying as required the diameter of either the external
containing tube or the internal heating tube or both of them the area through which
the liquid under treatment flows may be regulated so as to give that speed of flow
through the different parts and sections of the apparatus which in working is found
to give the best results by preventing or lessening the deposit of scale on the heating
tubes, the amount of heating surface being adjusted or varied to suit required
conditions.
The improved apparatus may be constructed either as a multiple or as a single effect
apparatus.
When constructed as a multiple effect apparatus, the several divisions thereof may
be arranged in vertical series and the different chambers, ports and passages for
supplying steam and liquid to the heating tubes and the aforesaid annular spaces
surrounding them and for connecting together the different series of. tubes in each
apparatus or division thereof are formed within the walls or casing of the apparatus
and are of very simple construction and arrangement being preferably in the form of
cast iron casings connected together, one above the other by flanges with bolts or
rivets.
At the same time it is to be understood that we do not limit the application of the
present Invention to multiple effect apparatus wherein the different sections are placed
vertically over one another as the said different sections may be placed side by side
with suitable vapor connections between them and the liquid under treatment
transferred from section to section by means of the difference in pressures at which
the sections are worked by pumping or otherwise.
A single effect apparatus constructed in accordance with our Invention having a
separating chamber, cellular liquid circulating chambers and connected evaporating
tubes (steam boxes with heating tubes passing through the evaporating tubes) may be
operated alone with good results. It is therefore explained that the improvements
comprised under our present Invention are not confined to multiple effect apparatus
alone, although the arrangement favors the use of two or more evaporators or divisions
of the apparatus connected in series for operation as a multiple effect apparatus.
In order that our Invention may be properly understood and readily carried into
effect, we will now proceed to describe the drawings hereunto annexed.
Figure 1, represents a longitudinal vertical section of the upper evaporator of the
series of a multiple effect apparatus taken on the line a¹, a¹, in Figure 3.
Figure 1, is a sectional detail view.
Figure 2, is a horizontal section of a portion only of an evaporator taken on the
line y, y, in Figure 3.

page_text: Figure 3, is a vertical transverse section on an enlarged scale taken partly on the
line X, X, and partly on the line Z, Z, in Figure 1.
The sections B', and B2, of a multiple effect apparatus and their corresponding
separating chambers A³, and A2, and of both of which two only are shewn on the
annexed drawings, are arranged in vertical series, it being understood that three, four
or more of such evaporators may be used or combined in a similar manner.
We preferably construct the divisions or sections of our apparatus of rectangular
boxes or compound chambers H, of cast-iron. Each such chamber embodies the outer
vertical walls of the apparatus and each contains a separating chamber, a transverse
steam supply box, a cellular liquid receiving and supply chamber, a vapor or steam
port leading to the next evaporator, and a liquid port also leading to the next
evaporator. In the upper box or chamber H, the steam supply box F¹, extends
transversely between the outer side walls, and from the top to near the bottom, and is
arranged a short distance in front of the external rear wall h. The space between the
steam box F, and rear wall h, constitutes the liquid receiving and supply chamber L,
and has connected with it through the wall h, the evaporating tubes 6. The heating
tubes f, connect with the box ¹, through its rear wall and each such tube passes
through the chamber L, and through an evaporating tube b, to the rear tube sheet I,
in which the tubes f, are securely fitted. The evaporating tubes b, are secured at
their front ends in the plate h, anil at their rear ends in the return-bend head or liquid
chamber C. The tubes f, and b, are preferably secured at their ends by means of
screwed threads cut in or on thein or by plain conical collars as shewn on the drawings
in order to allow of the tubes being easily removed when requiring to be cleaned and
for convenience of transport. The tube sheet f, is secured to the head C, and is
enclosed by the outer liquid and steam-tight cap D, which forms a rear steam box. K.
The return-bend head C, is provided with transverse partitions c, dividing it into cells
for properly connecting the ends of the evaporating tubes b, in vertical series. Vertical
partition plates, not shewn in the drawings are provided for separating the ends of the
adjacent series of tubes. The chamber D, is similarly divided into cells by horizontal
partitions a, shewn in Figure 2, and indicated by dotted lines in Figure 3, for
connecting the front ends of the tubes in vertical series.
The steam boxes F, and K. of each division of the apparatus may each have one or
more horizontal plates so arranged as to cause the steam to flow backwards and
forwards through the steam heating tubes f, and a steam supply pipe may be fitted in
the cap D, for admitting steam to the heating tubes f. As shewn in the drawings, a
steam inlet pipe or port F, connects with the box F. The steam boxes F, F, of.
each division of the apparatus are provided at the bottom with ports g-leading into
the passages E1, E2, for the escape of the water of condensation or the water of con-
densation may be removed by pipe connections from the side of the steam chambers F,
or K. A hole is made in the front plate of each passage E, E³, opposite the port g,
and closed by a plug gl, for giving access to such port, or by boring it in the first
instance. A liquid feed pipe or port L, connects with the top of the cellular
chamber L', above the transverse trough m. The bottom plate of this trough is
provided with a port for each top cell in the chamber I, with which the top
vaporizing tubes b, connect. A sliding plate or register n, Figure 1ª, having ports
corresponding to those in the trough m, is fitted in a groove or recess extending
across the top of the chamber L, and is provided with a handle passing through a
gland or stuffing box, which is however not shewn in the drawings, the same. being
well understood.
The transverse passage G, below the box F, permits the escape of hot. liquid and
vapor from the lower vaporizing tubes into the separating chamber A¹.
A lateral vertical passage E', E³, respectively in each division of the apparatus
having at its top a port e, is formed in the chamber A', and top part of the chamber A³,
for the passage of vapor, or steam from the chamber A¹,.into the distributing box F2,
of the next evaporator. A port e¹, Figure 3, is made in the adjacent plates of the
chambers A1, A2, within the walls of the passage E¹.
The steam passages E¹, and E2, of each division of the apparatus are preferably.

page_text: arranged alternately at opposite sides of the separating chambers, that is to say, the
passage E, is placed at the right-hand side and the flue E, at the left-hand side, so
that they may not interfere one with another as shewn in Figure 3.
The passage E, is provided with the inlet port e, at the top of the chamber A2, as
shewn in horizontal section, Figure 2, and in vertical section Figure 3, and such
passage descends into the separating chamber and connects with the steam box of the
next lower evaporator but which is not shewn in the drawings.
An exhaust pump and a condenser may connect with the last vapor passage of
the apparatus. A port o, is made in the bottom plate of each separating chamber
directly above the trough m¹, and feed register n, for the passage of the partially
concentrated liquid from one separating chamber to the tubes of the next evaporator.
A manhole k, is made in the front plate of each separating chamber and is closed
by a cap, not shewn in the drawings.
The action or mode of operating the apparatus is as follows:-The liquid to be
concentrated being supplied by the pipe L, its flow to all the upper vaporizing tubes b,
is regulated by the register in the groove n, and it flows downwards through all the
tubes of each vertical series; and steam being admitted to the distributing boss F¹, or
through the box K, it passes through the heating tubes f, or, by means of horizontal
division plates placed in the chambers F¹, and K, is caused to flow backwards and
forwards through the tubes. The resulting partially concentrated liquid and hot
vapor or steam are discharged from the lower tubes into the separating chamber A',
in which the vapor rises and passes to the condenser if worked as a single effect
apparatus or its working multiple effect into the passage through which it flows into
the distributing box F, for supplying the heating tubes of the next evaporator while
the liquid passes to the withdrawing pump in single effect or in multiple effect
apparatus through the port o, in the bottom plate and into the trough m¹, below,
where its flow into the top vaporizing tubes of the section is regulated by the sliding
register in the groove n. The vapor and liquid flow in the manner above described,
through all the sections of the series, and the concentrated liquid is drawn off from
the bottom of the last separating chamber.
The feed registers or regulators referred to are so arranged that, while serving to
limit the admission of liquid under treatment to the different series of tubes, to the
quantity found to give the best results they can at any time be widely opened to wash
away by a temporary increase in the quantity of liquid, any obstruction which may
collect about the inlet parts. Should a coating of salts, or other matter, form upon
the heating tubes such tubes can be readily withdrawn by first removing the cap D,
and then scraped and replaced.
On the annexed drawings, we have not thought it necessary to shew the construction
of a single effect apparatus made according to our present improvements, as the
same will be obvious from the drawings we have given, it being here explained that
such single effect apparatus consists of one division or section of the apparatus shewn
in the annexed drawings.
Having now particularly described and ascertained the nature of our said Inven-
tion and in what manner the same is to be performed, we declare that what
we claim is:-
1. In vacuum tubular apparatus for evaporating, concentrating and in some cases
distilling liquids, the general arrangement and construction thereof of single or
multiple effect apparatus, substantially as hereinbefore described and shewn upon the
annexed drawings, Figures 1, 1, 2 and 3.
2. In tubular vacuum apparatus for evaporating, concentrating, and distilling
liquids the leading of the steam or vapor through a heating tube or tubes each of
which tube or tubes is contained within a larger tube or tubes, the annular space
between the internal heating tube and the external containing tube forming the
passage through which the liquid flows while under treatment.
3. The vacuum tubular apparatus for evaporating, concentrating and distilling
liquids constructed with heating tubes passing through tubes containing the liquid,

page_text: the employment of a regulator or feeding device or the mechanical equivalent thereof,
substantially as and for the purposes hereinbefore described and shewn upon the
annexed drawings.
4. In vacuum tubular apparatus for evaporating, concentrating and distilling liquids,
constructed as described having the heating tubes within those containing the liquid
under treatment, the arrangement and combination of the chambers each containing a
steam box, a separating chamber and when arranged to work multiple effect a port
connecting each such separating chamber of one division of the apparatus with the
steam box of the division next below it, or alongside of it, substantially as hereinbefore
described and shewn upon the annexed drawings.
. 5. In vacuum tubular apparatus for evaporating, concentrating and distilling liquids
constructed as described, the arrangement and construction whereby each heating
tube as well as each surrounding tube capable of being removed separately from their
respective tube plates when required, substantially as hereinbefore described and shewn
upon the annexed drawings.