Improvements in and in Apparatus for Distilling water.
Year: 1886

page_text: Date of Application, 9th Mar 1886.
Complete Left, 6th Dec., 1886.
Complete Accepted, 7th Jan., 1887.
Improvements in and in Apparatus for Distilling water.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of
53, Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent
Agents, do hereby declare the nature of this Invention to be as follows :--
This Invention relates to improved apparatus for distilling sea and other water and
separating it from the salts and other impurities in solution in order to render the
water potable.
The principle on which the apparatus is based and whereby it is enabled to operate
in a very economical manner, consists in evaporating a portion of the liquid and
utilizing the internal latent heat of this first portion (i.e. the quantity of heat
employed to produce the disaggregation of the molecules) to evaporate a second
portion and then utilizing the steam from this second portion to evaporate a third
portion.
Similarly utilizing the internal latent heat of this third steam to evaporate a fourth
portion and so on in succession until the loss of heat due to the loss of the external
latent heat (i.e. the quantity of heat expended in performing the external work)
renders any further prolongation of the operation practically useless. The cost in
fuel diminishes with the number of operations, each requiring an exactly similar
apparatus, but inversely it increases in proportion to the price of the apparatus
employed, that is to say to the increase of total heating surface. The minimum of
cost will therefore be a function of the cost of the fuel and of each element of the
apparatus. Each element consists 1st of a strong sheet iron casing capable of
resisting the pressure of the steam produced, 2nd of a worm or system of tubes,
forming the heating or condensing surface placed within the casing and immersed in
the liquid to be distilled and 3rd of a chamber receiving the condensed water. Steam
enters the worm from the preceding apparatus of the series at a pressure superior to
that to be produced in the apparatus under consideration, which steam in circulating
in contact with surfaces cooled from 10° to 12° C condenses in the proportion
(according to Messrs. Thomas & Laurence) of 1 calorie per second per square
metre, for each degree of difference of temperature, and each kilogramme of con-
densed steam from the preceding apparatus will have given up to the liquid the whole
of the internal latent heat which it contained and formed fresh steam at a lower
pressure which will play in the next apparatus, the same part as the steam has played

page_text: in the one under consideration. It has been mentioned above that the cost in fuel
of the distilled water obtained diminishes with the number of apparatus in series. I
will suppose five apparatus to be employed and will proceed to describe the operation
in each, both practically and theoretically.
The liquid to be distilled circulates from the first to the last of the series of
apparatus which I will distinguish by Nos. 1 to 5 and in passing from No. 1 to No. 5
it increases in density in each until it reaches a maximum and is discharged after
evaporation in No. 5. Similarly the fresh water produced by the condensation of the
steam in the several apparatus, follows the same course passing in succession through
the whole series and increasing in volume and becoming cooled, that is to say, giving
up units of heat, which are utilized in each of the apparatus.
Suppose sea water is to be distilled having a density of 3°. 5 Baumé and that it is
desired to produce 1000 kilogramines of fresh water with a maximum concentration of
10°. 5 Baumé for the sea water. To attain this result 1333 kilogrammes of sea water
must be treated which, would first pass into No. 1 apparatus. After having heated
this sea water by the waste heat of the last steam from No. 5 apparatus, it is
introduced by means of a Giffard injector or feed pump at a temperature of 90° C.
Suppose also that the heating agent employed is steam from a generator at 5 atmo-
spheres or 150°. 2 C..
The following calculation will show how much steam must be supplied from the
generator in order to produce 1000 kilogrammes of distilled water in the five
apparatus.
There will have been required
195 228
503.110
kilogrammes of stéani
1st. result. The generator will thus have produced 386 kilo-
grammes of condensed water at 140° C which represents
(the efficiency of the generator being reckoned at 8 kilo-
grammes per kilogramme of coal)
386
848 kilogrammes of coal.
There will therefore pass out of apparatus No. 1
1st. 386 kilogrammes fresh water at 140° C.
2nd. 1333
at 140° C
-
- 225 = 1108 kilogrammes concentrated sea water

page_text: There are then in this apparatus 312 972 cal. of which a portion
can form steam at 2.5 At.
= 127° and the remainder remain in the
liquid.
The nortion remaining will be 1404 kilourammas v 1970-
189 738 and
Together 611 fresh water at 127°
Total of sea and fresh water 1481* x 127°=
3rd. 238 steam at 127° carrying 238 × 156.726
16
12

page_text: There will therefore pass out of apparatus No. 4.
1st. 355 sea water at 100°
2nd. 386 water produced in the generator.
* "
225*
238k
do
do
do
do
251k do
do
apparatus No. 1,
apparatus No. 2.
apparatus No. 3.
3rd. 264 steam to be condensed which might by the aid of a vacuum work in the
same way in a fifth apparatus.
To sum up, by arresting the operation at this point we shall have produced with a
consumption of 48* coal 1364* or
1364
48
=
28 water per 1k coal.
This result shows that with one more apparatus in which the work would be
performed at 90° or 0.70 of an atmosphere we should have easily produced 250k inore
which would raise the result to 1614 per 48* or 33* per 1*.
The calories passed out of apparatus No. 4 are represented by
1st. 355 extraction at 100°
2nd. 1100 fresh water at 100°
35 500 calories
110 000
276 180
of which
part is utilized in the last condenser to heat the feed water of the generator 20
and of the apparatus which for the operation just explained will be
1st. for the generator
384*
2nd. for the apparatus
1333
154 000 lost.
unless the operation be prolonged with a greater number of apparatus.
If one considers the point of departure which is the number of calories taken from
the generator 384 × 65 3 250 000 calories there will only have been lost 96 000 cal.
by the changes of which the mean is 8% for each condensation.
==
It is evident that the net cost will vary according to the price of the, coal and the
interest of capital expended on the apparatus, then construction and cost should
therefore receive particular attention without omitting to consider 1st a continuous
regular and automatic working to economise labor 2nd the reduction of repairs 3rd
the volume 4th the weight and the price.
Each apparatus is constructed as represented in the accompanying drawing, of the
same constituent parts, viz. a boiler shell A, closed at both ends and to the front end
of which is fitted at the lower part a tube-plate-B, provided with flanges; each-hole-
in which receives a tube Y, extending the entire length of the cylinder and closed at
the other or free end, the tube being fixed in the tube plate B, by means of a screwed
gland. packed with indiarubber to make a tight joint like the tubes of surface
condensers. The chamber formed by the tube plate is closed by another plate D,
having holes tapped in it to receive as many tubes X of smaller diameter open at each
end and extending concentrically through the tubes Y, for about three fourths of their
length. The steam entering the chest E, passes through the smaller tubes and returns
to the chest F through the annular space between the tubes X, and Y, whereby it
becomes cooled by contact with the tubes y.
0, C, C, cast iron covers ribbed on the interior and inaking a double joint with the
tube plates D and B,

page_text: are mounted each
G, G, G, water gauges and cocks, the tubes on which they
being in communication at top and bottom with the shell A, A, or A2, and having
inlet and outlet branches for connection with pipes L M &c. H, steam inlet pipe from
boiler connecting with No. 1 apparatus. H1, H2 inlet pipes conveying the steam
produced in the 1st and 2nd apparatus into the 2nd and 3rd apparatus respectively,
the steam produced in the 3rd apparatus being conveyed to the condenser along with
the whole of the water condensed in the three apparatus.
I, I, I, outlets for condensed water provided with three way cocks J, J¹, J, for
drawing off the condensed water or conducting it to the succeeding apparatus.
I, sea water inlet pipe to the 1st apparatus to which it is supplied by means of an
injector or pump. M, outlet from No. 1 apparatus communicating with the inlet L',
of No. 2 apparatus, and so on for M', and L. M2, outlet for the water saturated with
salt which is discharged into the sea. By means of the present invention a free
distillation is obtained at each of the tubes while all the parts can be readily cleaned
without taking to pieces.
The supply to each of the apparatus is regulated by a constant level with float
actuated by the succeeding one, that is to say, if the level in No. 3 apparatus falls, its
float will raise the feed Hoat and open the supply from apparatus No. 2 until the
proper level is regained, and similarly for the others. The passage of the condensed
water from No. I apparatus to the succeeding ones is also regulated by means of
automatic floats, so arranged as to always leave a little water in compartment Fin
order that the generating steam in one apparatus shall not communicate with that in
the next. All the apparatus in a group are alike but each group is formed of
apparatus of different dimensions, according to the heating or condensing surface
required for obtaining the quantity of water desired.
The following table gives an example of the dimensions of the apparatus in the
several grouns arranged for producing different results.

page_text: Improvements in and in Apparatus for Distilling Water.
I, ALEXANDER MELVILLE CLARK, of the firm of A. M. and Wm. Clark, of 53,
Chancery Lane, in the County of Middlesex, Fellow of the Institute of Patent Agents,
do hereby declare the nature of this Invention (a communication to me from abroad by
Paul Oriolle of Nantes, France, Engineer) and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following statement:
This Invention relates to improved apparatus for distilling sea and other water and
separating it from the salts and other impurities in solution in order to render the
water potable.
The principle on which the apparatus is based and whereby it is enabled to operate
in a very economical manner, consists in evaporating a portion of the liquid and
utilizing the internal latent heat of this first portion (i. e. the quantity of heat
employed to produce the disaggregation of the molecules) to evaporate a second
portion and then utilizing the steam from this second portion to evaporate a third
portion. Similarly utilizing the internal latent heat of this third steam to evaporate a
fourth portion and so on in succession until the loss of heat due to the loss of the
external latent heat (i. c. the quantity of heat expended in performing the external
work) renders any further prolongation of the operation practically useless. The cost
in fuel diminishes with the number of operations, each requiring an exactly similar
apparatus, but inversely it increases in proportion to the price of the apparatus
employed that is to say to the increase of total heating surface. The minimum of
cost will therefore be a function of the cost of the fuel and of each element of the
apparatus. Each element consists 1st of a strong sheet iron casing capable of resist-
ing the pressure of the steam produced, 2nd of a worm or system of tubes forming
the heating or condensing surface placed within the casing and immersed in the liquid
to be distilled and 3rd of a chamber receiving the condensed water. Steam enters the
worm from the preceding apparatus of the series at a pressure superior to that to be
produced in the apparatus under consideration, which steam in circulating in contact
with surfaces cooled from 10° to 12° C condenses in the proportion (according to
Messrs. Thomas & Laurence) of 1 calorie per second per square metre, for each degree
of difference of temperature, and each kilogramme of condensed steam from the
preceding apparatus will have given up to the liquid the whole of the internal latent
heat which it contained and formed fresh steam at a lower pressure which will play in
the next apparatus, the same part as the steam has played in the one under consider-
ation. It has been mentioned above that the cost in fuel of the distilled water
obtained diminishes with the number of apparatus in series. I will suppose five
apparatus to be employed and will proceed to describe the operation in each, both
practically and theoretically.
The liquid to be distilled circulates from the first to the last of the series of apparatus
which I will distinguish by Nos. 1 to 5 and in passing from No. 1 to No. 5 it increases
in density in each until it reaches a maximum and is discharged after evaporation in
No. 5. Similarly the fresh water produced by the condensation of the steam in the
several apparatus follows the same course passing in succession through the whole
series and increasing in volume and becoming cooled that is to say giving up units of
heat which are utilized in each of the apparatus.

page_text: Suppose sea water is to be distilled having a density of 3°.5 Baumé and that it is
desired to produce 1000 kilogrammes of fresh water with a maximum concentration of
100.5 Baumé for the sea water. To attain this result 1333 kilogrammes of sea water
must be treated which would first pass into No. 1 apparatus. After having heated
his sea water by the waste heat of the last steam from No. 5 apparatus, it is introduced
by means of a Giffard injector or feed pump at a temperature of 90° C. Suppose also
hat the heating agent employed is steam from a generator at 5 atmospheres or
50°.2 C.
The following calculation will show how much steam must be supplied from the
generator in order to produce 1000 kilogrammes of distilled water in the five

page_text: There will therefore come from apparatus No. 2.
1st. 870 kilogrammes sea water more saturated at 127°.
2nd. 386 kilogrammes water from the generator.
"
225 kilogrammes water of steam produced apparatus
No. 1.
Together 611 fresh water at 127°.
Total of sea and fresh water 1481* x 127° =
3rd. 238 steam at 127° carrying 238 × 156.726
168
12
535
There will therefore pass out of apparatus No. 4
1st. 355* sea water at 100°
2nd. 386 water produced in the generator.
225 do.
do.
27
-
238* do.
do.
251* do.
do.
apparatus No. 1.
apparatus No. 2.
apparatus No. 3.
3rd. 264 steam to be condensed which might by the aid of a
vaccum work in the same way in a fifth apparatus.

page_text: To sum up, by arresting the operation at this point we shall have produced with a
consumption of 48* coal 1364* or = 28 water per 1* coal.
1364
48
This result shows that with one more apparatus in which the work would be
performed at 90° or 0.70 of an atmosphere we should have easily produced 250* more
which would raise the result to 1614* per 48* or 33* per 1*.
The calories passed out of apparatus No. 4 are represented by
Lot
255 Atraction at 1000
DE FOO
To sum up, by arresting the operation at this point we shall have produced with a
consumption of 48* coal 1364* or
28 water per 1* coal.
1364
48
=
This result shows that with one more apparatus in which the work would be
performed at 90° or 0.70 of an atmosphere we should have easily produced 250* more
which would raise the result to 1614* per 48* or 33* per 1*.
The calories passed out of apparatus No. 4 are represented by
1st
255 extration of 1000
2nd. 1100 fresh water at 100°
-
3rd. 264 steam carrying off the internal
latent heat
- 261 105
25 500 calories.
110 000
130 C80
276 180
of which part is utilized in the last condenser to heat the feed water of the generator
and of the apparatus which for the operation just explained will be
1st. for the generator
2nd. for the apparatus
-
384*
1333
unless the operation be prolonged with a greater number of apparatus.
If one considers the point of departure which is the number of calories taken from
the generator 384 x 653 = 250 000 calories there will only have been lost 96 000 cal. by
the changes of which the mean is 8% for each condensation.
It is evident that the net cost will vary according to the price of the coal and the
interest of capital expended on the apparatus, then construction and cost should
therefore receive particular attention without omitting to consider 1st.. a continuous
regular and automatic working to economise labor 2nd. the reduction of repairs
3rd. the volume 4th. the weight and the price.
Each apparatus is constructed as represented in the accompanying drawing, of the
same constituent parts, viz. a boiler shell A, closed at both ends and to the front end
of which is fitted at the lower part a tube plate B, provided with flanges, each hole in
which receives a tube Y, extending the entire length of the cylinder and closed at
the other or free end, the tube being fixed in the tube plate B, by means of a
screwed gland packed with indiarubber to make a tight joint like the tubes of surface
condensers. The chamber formed by the tube plate is closed by another plate D,
having holes tapped in it to receive as many tubes X of smaller diameter open at each
end and extending concentrically through the tubes Y, for about three fourths of their
length. The steam entering the chest E, passes through the smaller tubes and returns
to the chest F through the annular space between the tubes X, and Y, whereby it
becomes cooled by contact with the tubes y.
C, C, C², cast iron covers ribbed on the interior and making a double joint with
the tube plates D and B.
G, G1, G2, water gauges and cocks, the tubes on which they are mounted each-being
in communication at top and bottom with the shell A, A', or A2, and having inlet and
outlet branches for connection with pipes L M &c. H, steam inlet pipe from boiler
connecting with No. 1 apparatus. H1, H2 inlet pipes conveying the steam produced
in the 1st and 2nd apparatus into the 2nd and 3rd apparatus respectively, the steam
produced in the 3rd apparatus being conveyed to the condenser along with the whole
of the water condensed in the three apparatus.
I, I, I, outlets for condensed water provided with three way cocks J, J¹, J², for
drawing off the condensed water or conducting it to the succeeding apparatus.

page_text: L, sea water inlet pipe to the 1st apparatus to which it is supplied by means of an
injector or pump. M, outlet from No. 1 apparatus communicating with the inlet L',
of No. 2 apparatus, and so on for M, and 1 M², outlet for the water saturated with
salt which is discharged into the sea. By means of the present invention a free
distillation is obtained at each of the tubes while all the parts can be readily cleaned
without taking to pieces.
The supply to each of the apparatus is regulated by a constant level with float
actuated by the succeeding one, that is to say, if the level in No. 3 apparatus falls, its
float will raise the feed float and open the supply from apparatus No. 2 until the proper
level is regained, and similarly for the others. The passage of the condensed water
from No. 1 apparatus to the succeeding ones is also regulated by means of automatic
floats, so arranged as to always leave a little water in compartment F in order that the
generating steam in one apparatus shall not communicate with that in the next.
the apparatus in a group are alike but each group is formed of apparatus of different
dimensions, according to the heating or condensing surface required for obtaining the
quantity of water desired.
All
The following table gives an example of the dimensions of the apparatus in the
several groups arranged for producing different results.
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 :-
1st. A process of distilling sea and other water by means of a series of apparatus
each consisting of a shell provided with sets of concentric circulating tubes for the
steam, gauges and self-acting floats, and so arranged that in each apparatus the
internal latent heat of that portion of the liquid evaporated in the preceding apparatus,
is utilized to evaporate a second portion of the liquid and so on, as hereinbefore
described.
2nd. In a process of distilling sea and other water as described, the employment in
each apparatus of the series, of tubes Y closed at one end and containing smaller
tubes open at both ends, through which the steam is caused to circulate in order to
prolong its contact with the cooling surfaces, the said apparatus being also provided
with gauges and self-acting floats for maintaining a constant lovel in each of the
apparatus all as horeinbofore described.
A. MELVILLE CLARK.
By A. M. & Wm. Clark,
53, Chancery Lane, London,
Patent Agents.