CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF SALT
Year: 1839

page_text: REYNOLDS' SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
REYNOLDS, of Bridge Street, Blackfriars, in the City of London, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Sixteenth day of July, in the third year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
John Reynolds, Her especial licence, full power, sole privilege and authority,
that I, the said John Reynolds, my exors, adiñors, and assigns, or such others
as I, the said John Reynolds, my exors, adiñors, or assigns, should at any
time agree with, and no others, from time to time and at all times during
the term of years therein expressed, should and lawfully might make, use,
exercise, and vend, within England, Wales, and the Town of Berwick-upon-
Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF
SALT;" in which said Letters Patent is contained a proviso that I, the
said John Reynolds, shall cause a particular description of the nature of the
said Invention, and in what manner the same is to be performed, to be
inrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.
NOW KNOW YE, that I, the said John Reynolds, do hereby declare that
the nature of my said Invention, and the manner in which the same is to be
performed, is as follows:-
First, the nature of my Invention consists in causing the steam produced
by boiling brine or salt water in a close vessel to transfer its heat to, and
thereby boil brine or salt water in a second closed vessel, so that the steam

page_text: from such second vessel may in like manner transfer its heat to brine in a
third vessel, and so on, by maintaining in each of a series of closed vessels in
which brine or salt water is subjected to evaporation, such relative pressure
as will cause the respective boiling points of the brine or salt water contained
in each to be lower (or of successively decreasing temperature) from the first
to the last of the series, so that the steam or vapour produced from the brine
in each vessel may be condensed in a vessel of thin metal immersed in the
brine of the next succeeding vessel, in the order of decreasing pressures and
temperatures, by imparting its heat (or the greater proportion thereof) to the
brine in which the condensing vessel is immersed, such graduations of pressure
in the series of vessels being obtained either by diminishing a pressure super-
added to that of the atmosphere, or by diminishing the pressure of the
atmosphere in each vessel successively.
Secondly, the manner in which my Invention is to be performed will be
apparent by the annexed Drawings, and the description thereof.
Figure 1 shews the apparatus partly in vertical section, and partly in
elevation; Figure 2 is a plan. The same letters are used to designated similar
parts in both Figures. B is an ordinary boiler supplied with fresh or pure
water; its office is to transmit by means of its steam to brine to be evaporated
(and which is contained in vessels which I shall call "evaporators,") the heat
communicated to itself by the fire applied to it. This is effected by causing
(by means of a safety valve of suitable weight or depressive force) the
boiling point of the water contained in the boiler to be several degrees (say,
10 to 30°) higher than the boiling point of the brine in the first evaporator of
the series (marked E¹). By means of the steam pipes S and G¹, the steam
from the boiler is conveyed into the condenser C¹ (which is immersed in the
brine of the evaporator E¹) and is condensed therein by imparting a portion of
its heat (commonly called latent heat) to the brine surrounding the condenser;
the water produced by such condensation flow back by the pipe W into the
boiler; E', E, are evaporators or vessels in which brine or salt water 'are
subjected to evaporation; each communicates by the steam pipes H; S, and G,
with a condenser immersed in the brine contained in the evaporator next
succeeding it, in the order of decreasing pressure and temperature. C', C³, are
condensers immersed in the brine contained in the evaporators; they are
cylinders closed at top and bottom, with tubes of thin metal open at both ends
passing through them and through their top and bottom plates. Each con-
denser communicates by the steam pipe G and S with the boiler, or with the
evaporator next preceding (in the order of decreasing pressure and temperature)
the one in which it is placed, so that the steam or vapour may flow from the

page_text: boiler or evaporator into the condenser, and envelope the tubes which pass
through it. At the bottom of the condensers are the pipes W¹ and W',
through which the water produced by the condensation of steam is discharged.
Surrounding each condenser with a small intervening space is a cylinder of
thin metal, open at each end, the brine between the interior of which and
the sides of the condenser, and that in the tubes of the condenser will, when
heated and commixed with steam, flow upwards, and such portion as is not
converted into steam will flow downwards between the exterior of the cylinder
and the sides of the evaporator. W', W2, are the pipes which convey the
water from the condensers into the boiler or refrigerators; R, R, are the
refrigerators, which are close vessels containing closed cylinders, with tubes
open at both ends passing through their top and bottom plates, the tubes
occupying about half the interior space of the cylinders. The feed brine
enters at the bottoms of the refrigerators through the apertures A, and
ascending thro' the tubes, passes from their tops into the refrigerators,)
whilst the hot water from the condensers enters at the tops of the cylinders
containing the tubes, and descending in the spaces between the tubes is
discharged at the bottom through the pressure valves P, P. The feed brine
being cooler when it enters the evaporators than the steam pipes connected
with the condensers, is made to pass through a case, which envelopes the
portion of the pipe with which the brine in the evaporator might otherwise
come in contact, in order to prevent incrustation on the pipe; P, P, are the
pressure valves, which regulate the boil points of the respective evaporators,
by resisting the discharge of the water from the condensers, until the steam
has attained the required temperature and elasticity, or that which will over-
come the resistance with which the valves are respectively made to act,
such resistance being successively less in each pressure valve of the series.
A, A, are the apertures through which the feed brine (by a force pump or
otherwise) enters the refrigerators; the space betwen the apertures and the
tubes of the refrigerator is intended to contain a filter, should the brine
contain matter not in solution. F, F, are funnels to conduct the salt deposited
by the brine into the deposit vessels or receptacles D.; D, D, are the deposit
vessels or receptacles for the salt. By shutting off their communications with
the evaporators, (by closing a valve or cock in the pipe or neck which connects
them therewith, and opening the cocks in the pipe p, p, (which communicate
with a reservoir of brine at a higher level) the salt may be discharged through
the bottom valves without the admission of air; V, V, V, are valves or cocks
in the steam pipes and water pipes, by means of which the steam or water
may be directed into any of the condensers or refrigerators as may be required,

page_text: or any one or more of the evaporators or refrigerators be disconnected with
the others of the series, for the purpose of repairs or otherwise. The following
need not be exhibited in the Drawings or explained in detail, viz.:-Floats
in the evaporators to regulate the admission of feed brine; blow-off cocks for
the occasional discharge of air which may collect in the condensers or pipes;
forcing or exhausting pumps; tanks to contain brine; man-holes in the
evaporators to give access for repairing or cleansing stays or brackets to
support the condensers. I consider wrought or cast iron to be the most
suitable material for the evaporators and exterior vessels. The condensers and
the tubes of the refrigerators may be formed of copper, tin plate, sheet iron,
or other metal. As a provision against any injurious effects from galvanic
action when parts of the apparatus are formed of different metals, it may be
advisable to interpose at the conjunction of such parts some substance which
will not conduct galvanism, or to employ the method introduced by the late
Sir Humphrey Davey for the protection of the copper sheathing of ships. The
apparatus may be supported by a framework of iron or wood, or by masonry,
in any convenient way adapted to the premises in which they may be used.
Having explained the apparatus exhibited in the Drawing, I will next state
or trace the processes or effects which will take place therein when it is in
action or work. It being borne in mind that a decreasing pressure and boiling
temperature is maintained through the series of vessels from the boiler to the
last of the evaporators, then the steam from the boiler will be expelled
through the connecting steam pipes into the condenser immersed in the brine
contained in the first evaporator, which brine being cooler than such steam
will condense it absorbing a portion of its heat, and the water thereby
produced will flow back into the boiler through the pipe at the bottom of the
condenser. The heat absorbed by the brine will convert a portion of its water
into steam, which steam will be expelled through the connecting steam pipes
into the condenser immersed in the brine contained in the second evaporator,
which brine being cooler than such steam will condense it by absorbing a
portion of its heat. The water thereby produced will by the pressure of the
steam expelled from the condenser through the pipe communicating from its
bottom to the top of the refrigerator through which it will descend, and at the
bottom of which it will be discharged through the pressure valve; in its descent
it will pass (with an intervening partition of thin metal) the ascending feed
brine which supplies its place in the evaporator from which it was expelled in
the state of steam, and to which, in their opposite progression, it will transfer
its heat or the greater portion thereof. The heat absorbed by the brine in the
second evaporator as aforesaid, will convert a portion of its water into steam,

page_text: which steam will be expelled into the condenser in the third evaporator, where
the results will be similar to those produced by the condensation of steam in
the condenser in the second evaporator, and so on in like manner through as
many evaporators as may be employed. The last condensation may be effected
by placing.the condenser in a large vessel or tank (from which the feed brine
for the evaporators may be educted), and which may be maintained at the
necessary temperature by the influx of cold brine under the condenser, and by
the evaporation from the surface of the brine in the tank. The salt formed
in the tank may be removed means too obvious to be particularized, and
that formed in the evaporators will be deposited in the receptacle at the bottom
of each, from which it may be withdrawn or let out from time to time. The
number of successive processes of evaporation which may be effected depends,
first, on the difference between the highest and lowest temperature employed,
that is to say, between the respective temperatures at which the first and
the last condensation takes place; and, secondly, on the rate at which the
condensation is required to take place at each process, which latter will deter-
mine. the difference in temperature to be allowed between the condensing
point of the steam within the several condensers and the boiling point of the
brine which surrounds them; also to this difference should be added the
difference in temperature between the boiling point of the brine or salt water,
and the boiling point of pure water under similar pressure. Regard being had
to the above circumstances the number of processes of evaporation into which
any given range of temperature may be divided, will be readily determined.
It may be observed that the difference of temperature between the condensing
point of the steam within the condensers, and the boiling point of the brine
which surrounds them, should be in all cases sufficient to cause such a rapidity
of circulation of brine through and around the condensers as will prevent the
incrustation of salt or other matter upon them. In the event of its being
desirable to heat the feed brine to the boiling point in an open vessel, (in order
to free it from air, cabonate of lime, or other matter previously to its admis-
sion into the evaporators,) the several refrigerators may be made to discharge
the feed brine which is passed through them into a common receiver, where it
may be heated by steam from the boiler or otherwise to the required tempera-
ture, and be subsequently distributed by force pumps or otherwise to the evapo-
rators, when a successive decrease of temperature or of boiling points in the
evaporators is to be produced by a successive diminution of the pressure of the
atmosphere. That object is to be effected by causing the pressure valves (P in
the Drawing) to open into a vessel maintained in a state of vacuum (or nearly
so) by means of an exhausting pump, such valves having similar relative

page_text: weights or depressive forces, as the valves opening into the atmosphere
already described. Although I consider the apparatus herein described as
exhibiting generally the best mode of carrying my Invention into effect, yet
it is evident that the forms, dimensions, and relative proportions of the
several parts may be varied to a great extent, without materially affecting
the results or interfering with the essential objects of the Invention. So
also columns of water or brine may be substituted wholly or partially for
forcing or exhausting pumps or pressure valves, should local or other cir-
cumstances render it convenient, and any of the well-known kinds of cocks or
valves may be employed.
I claim as my Invention the maintaining in several vessels, in which brine or
salt water is subjected to evaporation, such relative degrees of pressure as that
the temperature or boiling point of the brine or salt water contained in each
shall be higher or greater than the temperature or boiling point of the brine
or salt water in the next succeeding vessel, so that the steam or vapour arising
from the brine or salt water in each may be condensed by imparting its heat
(or the greater portion thereof) to the brine or salt water, of lower tempera-
ture in the next vessel, in the manner and by such or similar means as are
herein-before described. I claim also as my Invention the methods herein-
before described of applying the heat of steam to brine or salt water, and of
collecting and discharging salt from the vessels wherein it is formed, whether
or not the same be used in conjunction with the above claimed method of
maintaining different degrees of temperature in several evaporating vessels.
In witness whereof, I, the said John Reynolds, have hereunto set my
hand and seal, this Sixteenth day of January, in the year of our Lord
One thousand eight hundred and forty.
JOHN REYNOLDS. (L.S.)
AND BE IT REMEMBERED, that on the Sixteenth day of January, in the
year of our Lord 1840, the aforesaid John Reynolds came before our said
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
'said, and all and every thing therein contained and specified in form above