IMPROVEMENTS IN APPARATUS FOR EVAPO- RATING BRINE AND OBTAINING SALT THEREFROM
Year: 1877

page_text: LETTERS PATENT to John Howard Worthington Biggs, of Mason's Buildings,
Liverpool, for the Invention of "IMPROVEMENTS IN APPARATUS FOR EVAPO-
RATING BRINE AND OBTAINING SALT THEREFROM."
Sealed the 28th August 1877, and dated the 8th May 1877.
COMPLETE SPECIFICATION filed by the said John Howard at the Office of the
Commissioners of Patents on the 8th May 1877.
"
IM-
JOHN HOWARD WORTHINGTON BIGas, of Mason's Buildings, Liverpool.
PROVEMENTS IN APPARATUS FOR EVAPORATING BRINE AND OBTAINING SALT
THEREFROM."
This Invention has for its object improvements in apparatus for evaporating brine
and obtaining salt therefrom.
The apparatus which I will first describe is designed to produce ordinary qualities
of salt and cylinder film salt in vacuo, by the following economical arrangements :-
In the first place, more perfect combustion is secured by causing the flames from
opposite furnaces to meet one another in combination with steam, air, &c., to
promote their perfect combustion.
In the second place, the heated gases are then passed (sometimes down a dryer)
over a fire heating a boiler or pans, where they are re-ignited in a further combustion
chamber (as from the down comer of a blast furnace) and do not escape to the
chimney until all their available heat has been taken up by the brine which they
heat. I sometimes further avail myself of the low heat remaining in these gases by
passing them over a surface heating pan which may be covered by a drying
chamber.
In the third place, the brine is progressively heated; first, by condensed water;
secondly, by condensed steam; thirdly, by the almost spent gases from the furnace;
fourthly, by the hot gases from the furnaces; fifthly, by circulating tubes in the
combustion chamber of the furnace; sixthly, in a concentrating pan; and seventhly,
admitted in this concentrated and highly boiling condition and thrown in spray on
heated surfaces, where a vacuum is maintained and where it boils at a greatly
reduced temperature. The salt is scraped off and passed (sometimes through a
dryer) into a double vacuum store, from which it can be emptied without the
necessity of stopping the machinery. The steam arising from boiling in vacuo

page_text: (sometimes utilised for driving the engine in it passage) is especially utilised for
giving off its latent heat to brine, again warming it in an earlier stage by the con-
densed water. The condensed water is utilised by running it down a vacuum tube
and (where there is sufficient fall) by using it to work hydraulic machinery. The
steam arising from brine boiling ex vacuo is utilised for giving off its latent heat to
brine, for heating colder brine with it condensed water, for supplying water for the
boiler, and sometimes for the vacuum column. The radiation from the pans, pipes,
&c., is protected by non-conducting cement, sand jackets, or brickwork; while
the pipes, stores, &c., as far as practicable, are lined with enamel and glazed
internally.
The pans are arranged to be emptied by hand or scraped and emptied by auto-
matic machinery. The salt is loaded into convenient waggons from rails placed
alongside.
The machinery is largely self-regulating, and convenient handles, and spy holes
in the vacuum chamber, &c., render the work of superintendence ensy. Most of the
machinery is housed, and thus greatly protected from damage by steam, air, &c. It
has additional regulating handles outside. I prefer to protect the metal all or in
part by having it galvanized, or prepard by Professor Barff's (or a similarly pro-
tective) process.
The mechanical features are self-regulating apparatus for the vacuum engine,
self-regulating apparatus for filling the pans and cylinder and maintaining the level of
the brine at a given height, self-acting intermittent scrapers, cooling the bottom
of the pan and cylinder with steam, producing a vacuum in the cylinder (and
sometimes store) by forcing out the air with high-pressure steam, and afterwards
condensing the steam for the heating of brine, preventing the rusting of the salt by
the cylinder by setting the scrapers a short distance from the heated surface, so as
to allow the formation of a thin layer of pan scale, lining or electro-plating the
interior of the cylinder with material less corrosive than that of which it is com-
posed, the introduction of hydrochloric acid or other chemicals into the cylinder,
the arrangement of the furnace pan with side pockets or pocket, heated by the
furnace gases, and the general convenience for superintending and working the
machinery and for the removal of salt; also blowing up the fires with steam or
air, or both, and sometimes feeding them by automatic machinery, clearing the
brine jets with steam, and further providing against their clogging by forcing the
brine through them with a pump or jet.
This apparatus is shown on Figures 1 and 2; Figure 1 is a plan; Figure 2 is a
vertical section from A to B.
Figure 3 is a section from C to D, showing furnaces, preparing tank, and cylin-
der, &c.
Figure 4 is a front elevation partly in section from I to J, showing construction
of salt store.
Figure 5 is a vertical back elevation, E to F, showing machinery and section of
feed box for E.
Figure 6 is a section of pan at G, H.
Figure 7 is an end view of chimney and pan partly in section.
Figure 8 is a side clevation and plan view of gearing for emptying salt store.
Figure 9 is a sectional plan view and elovation of the three-way cocks for admit-
ting air or vacuum to the salt store.
Figure 10 is a plan view and back elevation of the tube boxes.
Figures 11, 12, is a front elevation of tube boxes p¹ and p² with covers removed.
Figure 13 is a side elevation and plan of gearing for driving the screws.
Figures 14 show an end view and side elevation of machinery for actuating
scrapers and other details relating to the scrapers.
DETAILED DESCRIPTION (Summary).
A, cylinder; B, furnace; C, combustion chamber; D', auxiliary chimney and

page_text: I, salt store; J, J, salt shoot; A, E, gallery round concentrating tank; A, E*, short
gallery from A, E, to top of salt store; a, e, staircase; A, O, platform round pans;
J, brine supply pipe from brine head; K, brine trough for warming brine by con-
densed water; L, brine cistern for pump; M, pumps; N, upper pan, heating brine
by condensed steam; O, lower pan for boiling brine and working up waste heat
from the furnaces; P, circulating tubes for further heating the brine; Q, boiler,
furnace, and combustion chamber; Q, R, flues under pan O, showing steam jets,
flues, and dampers; R, chimney; A, S, pipe connecting cylinder with condensing
tubes; S, condensing tubes; T, air receiver; T, C, torrecellian column; U, air
pump; V, condensed water cistern for boiler; q, boiler; W, engine; E, H, engine
house; X, gearing; Y, pan scraper gearing; Z, pan scrapers; B, C, brickwork
walls.
A is an air-tight cylinder, the internal circumference of which is turned smooth,
and sometimes plated or lined with metal or material to lessen the action of the
brine upon the metal. It is made to revolve, and is heated by surrounding flues c, a,
from the furnace B, beneath. It revolves round a hollow axis a, h, and is provided
with stuffing boxes a, a, a man-hole a', one or more spray pipes a², a³, a
scraper a, which may be in one or more parts, a scraper slope a³, a stop board aº,
a float a for regulating the supply of brine, a screen a" for collecting steam,
vacuum pipes a¹, all, for exhausting the steam down A, S. The cylinder has
rails a¹ and racks a¹3 round its circumference, the rails rest upon support
wheels a¹-16, which are fixed to axles a, a17, turning in bearings on frame B, A,
or may be supported from frame C, A. The cylinder is turned by a wheel or
wheels a¹8, on shaft a¹, which is turned by the engine W by wheels, a pinion
wheel a, w, which can be thrown in and cut of gear when required. The girder
frame C, A, carries small guide wheels c, al 23, on and between which revolve the
parts of the cylinder marked a, a¹. It also has side brackets a, h¹. 2. attached to it.
Frame C, A, is supported on the brickwork walls B, C, containing the furnace B,
which are tied together with iron rods and corner plates b, c. The hollow axis a, h,
round which the cylinder revolves, and to which everything that is fixed in it is
attached, communicates at one end with the vacuum tubes by the pipe A, S, and at
the other with the salt store I by the elevator H. It is partially supported by
springs at the bottom of slotted bearings in brackets a, h2, and is kept from
turning round by a projecting fan arm a, h³, and by an adjustable pin a, *, in the
framing a, h', which projects into a slotted hole in the fan arm a, h³, thus allowing
the axis to move up and down, but not laterally. The object of this arrangement
is to adjust the scraper a, &c., to any angle that may be desired, and allow for the
rising of the axis from heat or other causes. A portion of the hollow axis a, h, in
the interior of the cylinder, is open at the top to admit salt falling from the
scrapers a down the salt slide a into the screw G which is moving internally,
carrying the salt to H, to facilitate which operation I cause grooves or projecting
ledges to be made down the bottom and sides of the hollow axis a, h, against which
the salt presses as it is carried forward to the elevator H, instead of turning round
and round in the screw G. In place of using the screw I sometimes employ an
endless belt for conveying the salt into H.
The cylinder is contained in a casing of iron and brickwork forming flues c, α,
round the side by which it is heated. The ends c, a¹, nearly touch the cylinder, and
may be fitted with ledges to prevent, as far as possible, the passage of heated gases.
A man-hole c, a², is provided in this casing opposite the man-hole a¹ in the cylinder..
The upper half of this casing is formed by the curved bottom of concentrating
pan E, in the upper part of which is a flue c, a*, communicating with the down-
comer. There is a pipe a, q, with a stop-cock communicating between the jets and
the boiler, with which I clear the jets and introduce steam into the cylinder. There
is also a pipe with cock leading into the cylinder from cistern h, a, containing
hydrochloric acid, which I sometimes introduce into the cylinder to assist the.
precipitation or to purify the salt. W, E, A, is a three-cylindered pump or circular
pump supported on a bracket from the sides of pan E, driven by steam or by a belt.

page_text: from the engine, with which I arrange when necessary, to force brine through the
jets a in the cylinder A; w, e, a 1, is a speed wheel and w, c, a 2, is a valve with
weight for allowing the brine to return by pipe e, a*, to the pan E, in case the
valve e, a¹, is closed.
The concentrating tank E is supported from girder frame C, A; it supplies hot
and concentrated brine to the jets a, in the cylinder below by the pipes e, a, in
which is situated the jet controlling valve e, a', governed by float a' in the cylinder.
Provision is made for supplying cylinder A with brine from other sources than
pan E, from which the brine may be run off if necessary to other pans or crystallizing
vessel; below this valve is a pipe and cock q, a, for supplying high-pressure steam
to the jets a 2 and 3 from the boiler q. The tank E is supplied with hot brine either
from the circulating pipes P or from the pan O by pumps M. A sensitive float e, w, in
cistern E, communicates with a steam throttle valve in engine W, increasing the
speed of the engine and pumps, in case the evaporation is very rapid in cylinder A
and a large supply of brine is being drawn down pipe c, a, out of tank E. The
tank is also provided with a direct supply of brine from the brine head by pipe b, h,
governed by a float b, h, which does not admit the cold brine unless the level of the
hot brine in E is too low. e, o, is an overflow pipe running the hot brine by
pipe e, o¹, into pan O; e, o, z, is a pipe for draining the tank entering the lower pan
at e, o. This pipe and all others about the apparatus are arranged with screw heads
and necessary cocks, so as to be easily cleaned by a brush or scraper internally.
The tank is supplied with hot brine by the pump m, o, either from the circulating
pipes P or direct from the pan O by pipe m, o¹, by opening 'm, o². There is n
division ex in the tank, causing the brine to circulate round the pan and become
further concentrated as it comes from pipe p, e, on its way to pipe e, a, for supplying
the jets.
The tank is covered by wooden lids e¹, which are raised by weights and chains,
and which are lined with felt and metal hinged to the curved part e³, from which
the steam rising from the brine is exhausted by pipe e, n, which has a steam jet
from the boiler at e, n', Figure 2; any steam that may condense on their surface
drains by a pipe to cistern V, provided with an overflow pipe, as either lid is raised,
it cuts off communication with its exhaust tube by a small plate fixed to the lid
which passes over its mouth. The outside of the pan is coated with non-conducting
cement or brickwork to prevent radiation of heat.
I sometimes arrange for tank E to be provided with a scraper; in this case I
prefer to make tank E, round, with a revolving scraper, elevator, or shoot. I some-
times work this pan in vacuo by connecting it with pipe A, S, providing it with a
vacuum salt store and dryer. B are the furnaces blown by blowers b, and fitted
with doors b¹ for admitting fuel and ash doors 63; their flames meet in combustion
chamber C, also fitted with steam jet pipes c, ash doors c¹, and other minor openings
that may be necessary for the introduction of air, &c., for assisting the proper
combustion of the gases. Two flues c, c, and c, d, provided with dampers c, c¹,
and c, d, the second of which dampers c, c', when open serves as a scraper, clearing
cylinder from soot, but I sometimes employ a separate scraper to remove the soot
from the cylinder, and a different arrangement of damper less exposed to the heat.
I sometimes arrange a steam pipe to blown steam into this flue to prevent the
cylinder being overheated; c, d, may be a swing damper. The upper flue com-
municates with a flue c, a, round the circumference of the cylinder, thence through
a V shaped hole into flue c, a*, passing to the down comer D; the other flue c, d,
communicates direct with the lower end of the down comer.
The down comer D is constructed of an iron tube lined with fire-brick, and
together with the flues with which it connects, is protected from radiation by brick-
work or sand jacket. At the upper end is a valve box d, with balance valve ď¹
opening outwards into auxiliary chimney d. This valve is worked with a wheel d
from a chain below, or will freely open in case of any explosion of gas.
The lower portion of the down comer has a soot door, and communicates by a
flue d, g, containing a damper d, q', and steam jet d, g, with the boiler furnace Q

page_text: and combustion chamber Q1, and thence to flue O, R, under pan O, leading to
chimney R, as hereafter described
I
I sometimes arrange a salt dryer round, and on the principle of the one shown in
Figure 11, Sheet 3, which may have an outer casing and be worked in vacuo.
sometimes let it pass through a vessel containing brine, in which I arrange a scraper
or scrapers with an elevator. In this case I prefer to have the bottom of the down
comer or vessel cone-shaped or curved.
The preparatory arrangements for supplying heated brine to tank E are trough K,
cistern L, pumps M, upper pan N, with condensing tubes S, lower pan O, with its
circulating tubes P. Trough K is fed with a constant supply of cold brine by the
pipe J and float J¹, communicating with the brine head, and itself feeds cistern L.
It contains two pipes, the first 8, t, communicating at one end with condensing
tubes S, and at the other with air receiver T, the other n, v, with the condensed
water gutters under upper pan at one end and with the cistern V at the other.
There are two pans N and O; the lower one O has long side pockets O¹, which,
together with its bottom, from three sides of the flue Q, R. There is a small com-
partment p, o, m, at the hot end which collects the hot brine for the pumps as it
returns from circulating pipes P, before it flows into the rest of the pan, and one or
more divisions o² placed across the pan; it is fed by brine from the upper pan by
pipe n, o, Figures 1, 2, at the chimney end; it is provided with one or more
mechanical scrapers Z, which are attached to sliding rods z¹, passing through the
sides of the pan and supported on small wheels 22. They are actuated by having
racks into which work pinions y, e¹, keyed on shaft y, z.
This shaft may be arranged to be moved with a winch, but is here arranged to bo
self-acting at given intervals by the reversing machinery Y, hereafter described.
In place of this arrangement I sometimes employ scrapers on an endless chain ;
I also sometimes employ screws or travelling belts in combination with one or more
elevators for emptying pockets. There is a coupling box at y, zx, which will
disconnect the further shaft. The pan is provided with a sensitive float n, o*,
admitting cold brine to the upper pan by the valve n¹ by cranks and levers n, o¹, 2, 3, 4,
It is cased in brickwork o*, filled in with sand to prevent radiation, and has
draining platform A, O, on either side, with connecting steps a, o 1 and 2 at each end,
and a tramway on one or both sides communicating with the salt store or shoot to
wagons or boats; o, l, is an overflow pipe from pan O into L, by which the engineer
regulates the speed of the pump m¹.
Immediately above O is placed pan N which inclines downward towards the
chimney, and contains a number of low partitions n*, which draw off the water
from the bottom of each compartment, and communicates with the lower pan by
overflow pipe n, o. It contains condensing tubes S, and is supplied by pumps m² by
pipe mx from cistern L; it is also provided with a supply pipe from the brine head,
governed by the valve n¹ and float n, ox. This pan N, together with the flap
doors N, O, forms a cover for the lower pan 0, confining the steam, and allowing
it to condense on its under surface. There are sloping shelves n, o, from the
centre of the pan to gutters n, v, at the side, those over the boiling portion of
the pan being composed of parts, one above the other, allowing the steam to pass
between them to condense on the bottom of pan N, but conducting the condensed
water which drops from its bottom into the gutters n, v, at their lower edges.
Toward the chimney end of the pan the shelves confine the steam between
themselves and the upper pan, and communicate by curved pipes n, oo, with swing
damper n, o, to a vertical pipe n, o8, in the chimney which draws off any exhaust
air. The condensed waters in the gutters n, v, is conducted by a pipe n, vl, through
the brine trough K into cistern V, which pipe is kept full of warm water by its
further end n, v³, being raised a few inches above its level; pipe s, t, is raised in the
same way at 8, t¹.
The flap doors N, O, are made of wood lined with felt and metal, and are hinged
at the top, and provided with hooks which catch on the outer edge of the pan; they
usually open inwards, but may be opened outwards when it is desired to skim the

page_text: pan or for other purposes. Each is provided with a triangular end abutting on the
next to prevent the escape of steam when any one of them is lowered.
The steam rising from tank E is drawn down pipe e, n, by jet e, n¹, and
blown between the sloping shelves n, o, and the bottom of the upper pan N, there
to condense.
The lower pan is heated by the gases coming from the down comer D, which pass
by flue d, g, over the boiler fire Q, which is fitted with a blower into a combustion
chamber Q*, and thence through an opening q, r¹, into the flue or flues Q, R, under
the lower pan O, or may pass by a lower flue q, ³, direct into Q, R; steam jets are
provided at q,, and d, q; dampers 9, 4, 5, connected by a chain, open and close
flues g, 1 and 2 for regulating the heat of the boiler. A damper d, q', is also provided
in the flue d, q, from the down comer D. I employ one or more steam jet pipes q, o,
as shown, with regulating cocks to blow steam along the plates of the lower pan
to prevent the formation of pan scale. The pans are intended to be of sufficient.
length or dimensions, or in combination with other pans to condense all the
available waste steam in pipes S, and to work up all the available waste heat from
the furnaces, not allowing more than 225 degrees of available heat to escape up the
chimney R, from which it is rather forced than drawn. The boiler q supplies high-
pressure steam for engine W, engine U, and the various jets and blowers. I prefer
using a peg top boiler, although any high-pressure boiler may be employed, having
due regard for the maintainance of sufficient space in the combustion chamber Q
for the proper ignition of the gases coming from the down comer D and fire Q.
Air, steam, &c., may be introduced into combustion chambers Q* and C for effecting
this purpose; there is a blower for the boiler fire.
The boiler together with its pipes is encased in brickwork or non-conducting
cement, as are also the pipes about the apparatus which conduct heated brine or
steam; T is the air receiver divided into an upper and lower compartment t¹ and t²,
by division at tx, connected by cock t³ and valve t, which adınits air into the upper
portion, but immediately shuts down in case the vacuum is in any way lessened in
the upper portion. The lower portion t communicates with the condensed water
pipe 8, t, and the Torrecellian column T, C, with suitable taps, and has an escape
valve for air t. The upper portion communicates with the salt store I by pipes t, i,
and cocks t, i, and with the exhaust engine U; it is fitted with an apparatus for
regulating the supply of steam to the exhaust engine U. This consists of a
lever t, u, communicating at one end with the steam throttle valve q, u, and at the
other with the piston of a small cylinder t, u, whose lower end communicates with
the air receiver T; this lever t, u, swings on an axis supported in bearings at t, u²,
which axis has a weight t, u, attached to it in such a way that when the vacuum
is properly maintained in the upper portion of receiver T the engine U is moving
slowly, but should the vacuum from any cause be lessened, the atmospheric air
presses the piston down, turns on more steam to the engine, and corrects the evil as
quickly as possible.
The exhaust steam from the engine is either used for some of the jets or
for the vacuum jet pipe q, a, 8; t, u, is an escape valve; g, t, is a tap with which
I sometimes blow steam into the salt stores to drive out the air and produce a
vacuum. Suitable valves are also arranged at the bottom of the store to let the
condensed water escape. The pipe A, S, connects with the hollow axis a, h, of the
cylinder at one end, and a steam box s¹ into which are fitted the condensing pipes S
at the other. It contains exhaust jet q, a, s, by pipes u, a, 8, communicating with
engine W by pipe w, a, 8, and engine U, an air escape valve a, sl, slightly weighted,
a stuffing box a, 82, through which a small shaft (, 83, passes, communicating with the
float a in cylinder A. This shaft actuates valvo e, a¹, in the brine feed pipe e, a,
by levers and rods a, 450, in such a way that when the level of the water in the
cylinder becomes too low more brine is admitted into the cylinder; W is the engine
at the end of whose revolving shaft w is a drum w, y, communicating with the rack
gear Y and speed wheels w, m, communicating with the pumps M, see Figure 1, 5.
A strap from engine drum w, y, runs on to a fast and loose pulley w, y 1 and 2, on a

page_text: 0
small shaft which also carries a drum w, y³. This drum has passing round it a
straight belt and a cross belt, communicating with two fast and one central loose
pulleys w, y, on a shaft y, at the end of which is a pinion y¹ working into
wheel y, keyed to a shaft y, 23. A rod guiding the two straps for fast and loose
pulleys w, y & 6, communicates with handle; a strap rod communicates with
handle; both handles are fitted with a balance weight actuated by notches on
scraper rod in such a way that when the scraper machinery is started the scrapers
take one to-and-fro motion and stop.
I sometimes construct this machinery so that it starts itself at given intervals;
otherwise it is left to the management of the man who looks after the pans, or the
engineer.
The speed of the engine can be regulated by handles q. w1 and 2, outside the
engine house, placed on the top of E, and by the left furnace, Figure 4.
The engine is fitted with expansion slide valves and two steam throttle valves,
one regulated by the governors and one governed by a float e, w, in the pan E, and
blows its exhaust steam either into vacuum jet q, a, 8, or into other jets about the
apparatus.
The engine, pumps, reversing gearing, air pumps, &c., are contained in a closo
room E, H, to protect them as far as possible from the corrosive influence of the
steam.
Although the engine may be regulated inside this room, there are cranks and
rods with regulating handles placed outside, one near the furnace, and the other
on the top of pan E for the convenience of the man in charge of the cylinder
apparatus. The pumps M are driven by a belt from the speed wheels w, m, on the
engine shaft to w, m¹, or may be driven by an independent engine or engines,
regulated by floats in the various pans, and are, No. 1, pump to lift the warm
brine from cistern L to upper pan N by pipe m, ol; No. 2, to circulate the brine
from the lower pan through the left half of pipes P by pipes m, ps, into the over-
flow compartment p, m, at m, p³; No. 3 is to force the water from cistern m, p, in
lower pan through m, p, through the other half of pipes P, up into the cistern E,
through pipes p, e; Pump 4 is to supply the boiler with water from tank V.
In place of using the pumps drawn, I sometimes use centrifugal or circular
pumps or jet pumps. A supply pipe and cock from brine head communicates with
tank E, pans N and O for filling the same, and sensitive floats b, h¹, and n¹, are
further arranged to admit brine from the cistern into these pans, should the brine
in any of them sink much below the proper proper level, with a view to preventing
accidents.
The circulating pipes P are arranged to work as follows:-They are connected
at each end with deposit boxes p and p², placed in the brickwork p, c, the
outside covers of which are easily removeable, so that the tubes may be readily
cleaned in case of any incrustation of salt. They are constructed to circulate tbe
brine independently of the pumps by pipes o, p¹, but are generally used in connec-
tion with the pumps, with which they are connected by pipes m, p. When the
pumps are used, pipe m, p', pumps brine through the right half of the pipes P and
out by pipe m, p³, into compartment m, p, of pan 0. The other pump pumps brine
through the left half of pipes P and through an escape valve p, e, up pipe p, e, into
cistern E. There are three taps p. 7.6, the handles of which communicate with one
another, moved by a handle at pº, so that when brine is not being forced by the
pumps into the pipes P, the brine from O is allowed to circulate freely in all the
pipes P through pipes o, p, m, p². Another pipe p10, with cock p¹ and cock pl, to
pump pipe m, pt, enables the brine to be forced direct into pan E through a second
clack valve in p, e¹, without interfering with the circulation of the brine in pipes P,
unaided by the pumps.
2,
I sometimes deepen the side pockets p¹ arranging an apparatus by which the
salt depositing in them can be blown out or removed.
I also sometimes arrange rods passing through stuffing boxes, which have scrapers
attached to them, to pass down the tubes to keep them free from incrustation,

page_text: These may be worked by machinery or hand. G is the screw, carrying salt from the
scraper slope, Figures 2 and 3, to the elevator H. Its axis g passes through the
stuffing box g¹ to which is keyed wheel g*.
I sometimes use a travelling band instead of this screw turned by a cross shaft
passing through a stuffing box.
I sometimes employ a drying apparatus to dry the salt in the vacuum. I accom-
plish this either by a division in cylinder A or by a cylinder worked externally
between hollow axis a, h, and elevator H, heated by the gases passing round it,
which I bring down from the down comer (Figures 14, 15, 16). H is the elevator,
receiving salt from the hollow axis a, h, by the screw G. The elevator is worked by
a small shaft h, passing through a stuffing box h¹, on to which is keyed a bevel
wheel h*. There is a glazed spy hole h³ for inspection. The salt is carried up and
delivered into valve box ¹, which is attached to salt stores I, which are divided
into two compartments in duplicate 11 and 3 Valve h, i¹, will cut off communication
between H and I, and has a hole in it at h, ix, which can be placed over either of
the stores in I, so as to allow one to be emptied while it directs salt into the other.
It is actuated by a rack h, 2, spur h, i³, keyed to shaft h, i, which is turned by
wheel h, , and chain h, 8. I I is the salt store, which is divided into two parts in
duplicate II and It is supported on walls 13. It is provided with stays i*, man
holes glazed spy holes on the top and front 13 (which together with the spy hole
in H may be cleaned with jets of air or steam) two valves and 5, at the bottom
communicating with the shoot I, I, moved by handles **, **, and two delivery
screws 7, one in each compartment, revolving on spindles ix, 27, Figure 13,
passing through stuffing boxes i, i, and turned by bevel wheels i* and ix2
'
I sometimes employ vertical screws, or dispense with screws, sloping the bottoms
of the stores directly to the shoot; 18 are escape valves. The upper portion of
the salt store is provided with pipes i, tand communicating with three-way
cocks i, 5, Figures 4 and 9, which are turned by rods and handles i, t 6, and
connect each half of the store with the vacuum pipe t, i, or with the open air. I
prefer to have the internal surface glazed or enamelled, as also, where practicable,
all other pipes or portions exposed to the action of the salt or brine, and to have it,
together with H, coated with non-conducting cement externally. The screw G,
the elevator H, and the screws 7, are driven by the shaft x driven by the
engine W; x1 slides on x by the hand x, x, which puts it in and out of gear
with x2, keyed to shaft x 3, which turns shaft x by bevel wheels x and x³,
which turns an inclined shaft x by bevel wheels x and x8; shaft x turns
shaft by bevel wheels x 10 and × 11; wheel x 13 is keyed on to shaft x
turning wheel g* which drives the screw G. The elevator H is driven by bevel
wheel x1, keyed on to shaft x, in gear with *. The screws 7, are driven from
upright shaft x, which drives shaft x 18 by bevel wheels x 15 and x 16 and friction
clutch x", on which a tube carrying double bevel wheel x1 slides, which can be
put in gear with bevel wheel or x, driving either of the screws i or in the
salt store. It is connected with a handle 17* in the front of the store, and has a
balance weight to keep the friction clutches in or out of gear.
0
12
'
The brine circulates as follows:-It enters trough K from pipe J, connected by
a cock with the brine head. It its passage to cistern L it is warmed from the
condensed water in pipes s, t, & n, v¹; it is then pumped into the compartment of
pan N, where it passes from the bottom of each compartment n, x, to the top of
the next in a zig-zag course, becoming thoroughly warmed before it reaches the
overflow pipe n, o, by which it enters the further end of the bottom pan O.
In its course it is further warmed by condensing the steam in tubes S, and by
the condensed water at their further end. It is also warmed by the steam from
the lower pan, condensing on the pan bottom. On entering the lower pan it is
heated by the waste furnace gases escaping to the chimney. As it proceeds to the
furnace end of the pan the hot brine from its surface passes through the bottom
of division or divisions of to the lower portion of the next compartment, where it is
thoroughly boiled. It is now pumped from near the bottom of the pocket (which

page_text: is protected from salt by a wire grating) through one half of the circulating pipes P
in the combustion chamber C, thence returning to the overflow compartment p, m
from which it is again pumped through the other half of circulating tubes P into
the concentrating cistern E. Here it enters highly heated, and in its passage round
the pan to the pipe e, a, which supplies the jets a² 3, becomes much concentrated.
In this heated and concentrated condition it is thrown by the jets a³ ³, against
the rotating interior of the heated cylinder, where, from being in vacuo, it evaporates
at a very low temperature. The thin film of salt deposited on the interior of the
cylinder from one or more spray pipes, passed through the highly boiling con-
centrated brine at the bottom of the cylinder, and then after passing one or more
jets (thickening a layer as it passes each), it is nearly or quite dried on the hot
plates of the cylinder, and is scraped off by at, slides down the slope a³ into the
hollow axis a, h, and is thence taken by the screw G, which conveys it by the
elevator H, into one of the compartments of the salt store I, also in vacuo.
One chamber being sufficiently filled with salt, communication is cut off with the
elovator by pulling chain h, i, and the salt deposits itself in the second chamber.
From these chambers it is alternately discharged by opening one of the valves 14 5,
by handles ¹×³×, by shoot I, I, into railway or other wagons or boat, or carried
to a store or taken by an elevator (sometimes through a dryer) for further manu-
facture. The salt in tank E is taken out by hand and put on the balcony A, E, to
drain, and shot down the shoot a, e¹, for similar treatment.
The salt collecting in the bottom pan is from time to time passed by the scrapers
into the left-hand pocket o, i, of the long pan O, some little finding its way by the
back action of the scrapers into the right-hand pocket. Care is taken by the man
in charge that the salt thus collecting is as far as possible kept clear from the side
of the pocket next the flue. When this pan contains sufficient salt some of the flap
doors are lowered to facilitate its being raked together, scooped out, and placed on
a platform A, O, to drain, when it is loaded into wagons, having moveable ends or
bottom, and conveyed for further manufacture or storage, or discharged into railway
wagons or boats. The salt from the upper pan is similarly handled.
The steam generated in cylinder A, together with any steam turned in from
engines W or U, is condensed in pipes S, giving off the latent heat to the brine in
the upper pan while the condensed water finds its way by pipe s, t, through
trough K into the receiver T, and thence down the Torrecellian column, which
maintains or helps to maintain the vacuum in the pipes, cylinder, and store
chambers; when, if there is a sufficient fall, I arrange to employ it for working
hydraulic machinery.
•
The steam arising from the concentrating pan E is drawn down pipe c, n, by a
steam jet e, n', and mingling with the steam rising through the sloping shelves n, o³,
from the boiling brine in the lower pan, gives off its latent heat to the brine above,
and thence passes away by pipe n, 08, into the chimney R; the condensed water
running down the gutters n, v, at the side of the pan, and passing in pipe n, vl,
through trough K, where it assists to heat the cold brine, passes into cistern V
through pumps m to supply the boiler q. This pump is also connected with the
water in the bottom of the receiver T.
The gases from the furnace, after heating the cylinder and concentrating tank E,
are brought down by the down comer D and flues d, q, over the boiler fire in Q,
where they might mingle with its heat in the combustion chamber Q*, generating
steam in boiler and pass under pan O, escaping up the chimney R after all the
available heat has been given off to the brine in the lower pan.
The man in charge may ascertain whether the cylinder is doing its proper work
by inspecting from gallery A, E*, through spy hole h², the salt in the buckets of
the elevator as it passes into the salt store, when he regulates the speed of tho
engine by handle q, w². The amount of salt collecting in the store may be
ascertained through the various spy holes arranged in the store, all of which are
kept clean by the occasional use of jets of air or steam.
The mechanical scrapers Z are self-acting at given intervals, and can be worked

page_text: all or in part by the clutch box 3, 2*.
handle y, z, or worked with a winch.
they are emptied by the operator, as
acting screws or bands and elevators.
The furnaces may be regulated by the dampers and various flue jets and blowers,
and if too much steam is got up in the boiler 7 the upper damper q,, is closed
which opens the lower q, r, the jet q, 13, turned on, and the heat from the furnace
passed direct under the pan O to the chimney R.
They may however be set in motion by the
When the side pockets are sufficiently filled
before described, or may be emptied by self-
The speed of the pumps is regulated by the speed wheels w, m, on the engine
shaft and pumps.
The course of circulation of the brine in pipes P may be regulated by the
pumps m and handles p10. 11, etc.
To facilitate the discharge of salt from I air may be admitted into the upper
portion of the store through pipe i, t¹, by turning handle i, t or 6. To obtain a
vacuum in the other half of I, preparatory to its being filled, the handle is turned
the other way and communication opened with the receiver T. This handle can
be further turned so as to cut off all communication from the store with either the
external air or vacuum. The salt may be rapidly discharged from the salt store
when valve or is opened "by putting screw 16 or screw in motion by
handle 3 and friction box handle i× 4.
To start the apparatus I run brine into pans N and O and trough K;
I open
damper din auxiliary chimney D¹ (to let the gases from the furnaces escape until
the fires are sufficiently burnt up to have either gases directed under pan O) and
damper d, q, in flue d, g, connecting the boiler furnace q, with down comer D and
damper a, d¹, in flue c, d, connecting the combustion chamber with C down comer D.
I close damper c, c², shutting off the heat from the cylinder, and damper q,,
shutting off communication with the chimney R; I light the three furnaces, get
up steam, open damper q, r, put on the jets d, g, and close damper d¹ in auxiliary
chimney D¹
I start the air pumps U, and exhaust the air from one or both halves of salt
store I, and close the tap t, i¹, communicating with the salt store.
I close the tap to the Torrecellian column; I blow steam into the cylinder A and
allow the air to escape by valve A, S; when the steam issues from this valve I
weight it. The steam now finds its way down the tubes S, forcing the air out of
them and the pipe s, t, and the lower portion of receiver T through escape valve t³
until it condenses in the tubes and partially fills the lower part of T with water.
I now open the tap t between the lower and upper portion of T, and exhaust the
air from the tubes S and cylinder A:
I start the Torrecellian column; I start the cylinder revolving, and open the
damper c, c¹, and at the same time shut the damper communicating between the
combustion chamber C and the down comer D, and allow the flame in the combus-
tion chamber C to heat the cylinder A.
I open the valve h, i¹, between H and I.
When the cylinder is sufficiently heated to be ready for producing salt I start
the screw G and elevator H by handle x, x ; I shut off steam from the cylinder
and open communication between H and one-half of the salt store; I start the
blowers to furnaces B. The vacuum being complete throughout the apparatus I
turn on the brine into the cylinder jet pipes a 2 and 3, when the apparatus is started.
The strap rod w, y, for reversing the action of the scrapers z is actuated by
notches on the rack rod z¹ pushing the forked end of the weighted lever w, y³, over,
first on one side and then on the other. The intermittent starting gear is arranged
as follows-In lieu of projections on rack rod z¹ there is a catch, which when
down in its passage raises a pin on lever w, y*, which is connected with the strap
fork w, 10, for pulleys w, y¹ and 2, by rods and wheels z, yl, 2, 3, 4, 5, 6, 7, and puts the
strap from the engine shaft on the loose pulley. When the catch 22 is raised by
pin being thrust forward it passes over the pin on lever y, z, and the scrapers
take another stroke until pin i is withdrawn, when the catch ² raises z, y', and

page_text: runs the strap on the loose pulley; pin i is actuated by notches on cam z, y³, by
rod ix, lever z, y³, forced up by a weight z, y10. Cam z, y, is fastened to a wheel
slowly revolving by a screw 12 turned by a wheel 13, a screw 14, and speed
wheel 15 driven by a band from the engine shaft. 2, y, also has a cam 16 with
one or more notches on its circumference. As each notch slowly comes round, the
projection on lever 17 allows the lever to fall and disengage the catch at its end
from catch 18; catch 18 is pivotted to and rests on lever 19, and when disengaged
is moved to the right by the weight 20, which moves the fork to the left, running
the strap on the fast pulley and starting the scrapers. On the upper end of
lever 19 is a pin 21, which in its passage to the right raises lever 17 and holds it in
position until the scrapers are stopped and the notch on cam 16 has passed from
under.
The scrapers may at any time be started by a handle at the end of rod 22 which
knocks up catch 18 by lever 23, which is usually resting against a pin in the frame
by weight 24.
Another form of apparatus which I have designed is intended to produce ordinary
qualities of salt, vacuum pau salt, vacuum table salt, with drying apparatus. The
brine is heated progressively by passage through pans, heated by steam and water,
and flues. The brine is boiled in a deep pan with a bottom arched to retain the
heat, and with spiral flues passing round its sides. It is further heated by hot air
blown into it. The vacuum pan is heated by spiral flues passing round its sides,
and by having a convex bottom heated by the steam and hot air in the pan below.
The pan above is similarly heated with the addition of steam tubes. The vacuum
tables are supplied with heated and sometimes concentrated brine; they are also
provided with revolving scrapers in ledge dryers; the salt from them is dried and
deposited in a vacuum store, which is emptied direct into wagons. The salt from
the vacuum pan is brought up by a screw, dried, and similarly stored. I sometimes,
with less advantage, arrange to have the vacuum store filled or partially filled with
boiling brine froin the pans, with which it connects by an opening or screw.
this case the salt displaces the brine in the store, and when the store is full com-
munication is shut off with the pans, the brine drained off into another pan, and
the salt emptied out. All the stores may be emptied direct into railway wagons.
In
All the pans are provided with self-acting scrapers, which may work at the same
or varying speed; which may have revolving knives or moving cutters, with
elevators and shoots into wagons; communication is also made with shelf dryers
round the down comers, also discharging into wagons. The furnace gases after
escaping from the down comers are used for another pan or pans, surface or other-
wise, or store. The steam and hot air and the condensed water are used for
heating brine, for a vacuum column, and where practicable for hydraulic machines.
The steam from the vacuum pan is sometimes used for the engines.
The mechanical features are, the shape and combination of the pans, placed
immediately one above the other; the way in which they are heated; the way in
which the condensed water drains from their roofs, and is afterwards used for
heating brine; blowing heated air, &c., into pans, and using it and the steam coming
from the hot brine for heating brine in other vessels; boiling brine in vacuo in
combination with scrapers; room for accumulating salt or salt stores, dry or con-
taining brine; the arrangement of the shelf and ledge dryers; shoots and stores for
delivering dried salt direct into trucks, railway wagons, etc., without passing
through any intermediate process; the coupling and cleaning of the coil pipes;
the system of combustion by which the flames meet for producing better combus-
tion; blowing steam on to pan bottoms and into the flues for preventing pan
scale; driving the engine by steam from vacuum pans boiling in combination with
scrapers; the self-regulating air pump; using scrapers in pans placed one above the
other, or in pans having metal roofs; maintaining a vacuum in pans with scrapers by
means of a vacuum column, and using the condensed water when applicable for
driving hydraulic machinery; using the spent heat from the furnaces for heating
surface pans, stores, or other pans; running heated or concentrated brine into

page_text: vessels, which may be heated for crystallization; the use of flues with one or more
scrapers passing through brine, in connection with a place for the deposit of salt, or
in connection with a store; in, or ex vacuo, condensing the steam arising from the
evaporation from pans or tables, on which there are scrapers for warming brine in
other vessels; working the scrapers at different speeds, and the cutting scrapers;
using the waste beat from film drying machinery for other pans, dryers, or
stores.
The pans, tubes, and pipes are protected from radiation and incrustation as in the
previous apparatus.
Figure 1 in Sheet 3 is a plan of the apparatus of towers 1, 2, 3, (2 and 3 being
in duplicate) and salt store G, shewing arrangement of engines and gearing, and a
sectional view of table E in tower 3.
Figure 2 is a front elevation of the duplicate towers 2 and 3.
Figure 3 is a section from A to B of tower 1 and salt store G.
Figure 4 is a section from C to D of tower 3, also showing position of tower 1,
engines, down comer, etc.
Figure 5 is a back view of tower 1, shewing engines.
Figure 6 is a section from E to F of furnaces and combustion chamber.
Figure 7 shews the coupling of the coil pipes.
Figure 8 is a plan view of table E.
Figures 9 and 10 are sectional plans of drier H.
Figures 11 and 12 are elevations partly in section of drier I.
Figures 13, 14, 15, and 16 are details of the same.
Figure 17 is a sectional view of the vacuum brine feed y.
A is the condensing pan, the first process pans, No. 1; B is the heating pans,
second process pans, No. 2; C is the concentrating pan, into which hot air is blown,
third process, No. 3; D is the vacuum pan, fourth process, No. 4; E, the vacuum
film tables and shelf dryers, fifth process, No. 5; F, vacuum salt store for same;
G, vacuum salt store for vacuum pan D; H, the dryer for vacuum pan D; I, salt
dryer to tanks A and B; J, salt dryer to tanks C; K, salt elevators for pans A;
L, salt elevators for pan B; M, salt elevators for pan C; N, screw elevator for
vacuum pan D; O, the furnaces; P, combustion chamber; Q, direct flue from
combustion chamber P to drying tables E; R, down comers; R¹, auxiliary chimnies;
S, exhaust flue to next pan, boiler, or store; T, air receivers; U, exhaust air pump
and engine; V, air compresser and blower; W, hot-air pipes in combustion cham-
ber P; X, brine pump; Y, YA, brine float boxes; Z, engine; A, A, gallery round
top of pans; A, B, T, girder carrying the shafts and z, crossing over pan B and
forked over pans A, A. This girder carries the bearings for the vertical shafts a¹, a¹,
and b; A, C, short lower gallery; A, A, and A, C, communicate with each other
and the ground by A, D, staircase.
The tower No. 1 contains three pans, Nos. 2, 3, 4, surrounded by spiral flues, com-
bustion chamber, and furnaces; towers Nos. 2 and 3 contain pans, one heated by
condensed steam and hot water, vacuum chamber 5 containing the film salt
tables E, E, and the salt store F. Between the towers is the salt store G and
dryer H belonging to tower 1. A gallery A, A, encircles the tops of the towers for
oiling the machinery. A short lower gallery A, C, enables the operator to super-
intend the vacuum tables, and both connect with each other and the ground by
staircase A, D. The towers 2 and 3 are built on arches to allow wagons for loading
to pass beneath.
Between tower 1 and towers 2 and 3 are the down comers R and
the salt dryers I, J, which communicate with a flue S leading to the boiler furnace
or another pan; R¹ are auxiliary chimnies used for lighting the furnace or cooling
the pans. The five pans are each provided with mechanical scrapers, elevators, to
remove the salt dryers and shoots for loading direct into wagons.
The two first, A and A, Figures 1 and 4, in towers 2 and 3, are heated beneath
by steam from the chamber E* containing the vacuum tables by coils at their sides
and in the drawing by a condenser. They are fed from the brine head or pump x, and
supply warm brine to pan B, tower 1. Sult forming in them is removed by

page_text: elevators through dryer I and passed down shoots direct into waggons, or may be
passed into a wagon without going through the dryer.
The pan B in tower 1 is heated from beneath by steam from vacuum pan D, and
by flues at the side, and by coils. It supplies heated brine to pan C, tower 1, and
salt from it is removed as from A.
Pan C has an arched bottom and is heated from beneath by the combustion
chamber, and by a spiral flue round its sides, and by hot air blown into it near its
bottom.
It supplies concentrated brine to pan D in vacuo, or may supply direct to
the jets for tables E. Its salt is emptied by an elevator and passed over dryer J
down a shoot to the wagons. There is a man-hole and a pipe and cock for draining.
Pan D is a vacuum pan placed over pan C, and heated by the vapour and air arising
from it, and by spiral flues at its side. It supplies heated and yet further concen-
trated brine to the vacuum tables in the chamber under pans A, towers 2 and 3.
Its salt is carried by a screw through a dryer into a vacuum store G. There is a
man-hole and a pipe and cock for draining.
The four vacuum tables E are situated in two chambers Ex and E* under
pans A and in towers 2 and 3. They are heated by flues which communicate with
those round pan C, but which are also arranged to communicate direct with the
combustion chamber of the furnaces. They are supplied with boiling brine from
the vacuum pan D or C, or other sources by jets. The steam arising in the process
heats the pan above it, and is drawn through the coils in pan A. The salt is
scraped from the tables over the ledges of a dryer and passes into a vacuum salt
store F.
The salt stores F in towers 2 and 3 receive the salt from the vacuum tables E
placed above them. The salt store G receives the salt from the vacuum pan D in
tower 1. They rest upon the arches and discharge into wagons stationed beneath
them.
A Torrecellian column removes the condensed water from the vacuum pan and
tables maintaining or helping to maintain the vacuum. The steam from the various
other pans after heating brine by passing through coils runs its condensed water
into cistern.
The furnaces are situated in tower 1 and are blown by blowers, their flames
meeting in a combustion chamber under pan C. The products of combustion after
heating various pans and tables pass through vertical salt dryers and down comers
into a flue, which communicates with the furnace or combustion chamber of another
pan, not shewn.
The engine drives the various machinery and three pumps; 1°, pumping brine to
the pan A; 2°, blowing air through the heating tubes for pan C; and 3° pumping out
the condensed water from the well into which the Torrecellian column discharges.
The steam for the engines is sometimes supplied from the vacuum pan before it is
passed on to the coils, otherwise it is supplied from a boiler, not shown.
The vacuum engine U exhausts the air from receivers T, T, connected with the
coils, the vacuum pan, and various vacuum chambers. It is governed by a vacuum
regulating valve-like engine U in Figures 1 and 2.
The pans A, chamber Ex, stores F, G, and the various parts of the apparatus
which are likely to radiate heat are coated externally with non-conducting cement
or brickwork. The stores, tubes, etc., exposed to the action of brine or salt are
where practicable glazed or enamelled internally.
The pan A contains in its centre a condensing dome A, E, and round its inner
circumference coils a³, in which steam and water circulate, and which with
dome A, E, and the heated bottom of the pan warm the brine; a is a scraper
keyed to a vertical shaft a¹ carried in bearings on girders a³, a, b, and passing
through a stuffing box a³, and is fitted with a travelling apparatus for keeping the
coils clean and rubbing their surfaces.
The salt collected in this pan is scraped into a hole a, which conducts it to an
elevator K, and discharges it down a pipe ¹ into the dryer I, whence it passes by the

page_text: shoot into the wagon; the pan is provided with n supply pipe and float from
the brine head or with a pipe from the pump X. It is also provided with a pipe for
emptying, and a feeding pipe to pan B. The salt can be discharged direct through 14
without passing through dryer I.
The pan B has a vertical shaft passing through its centre, and supported in
bearings in pillar p³. It is surrounded externally by flues p5, and has at its upper part
coiled pipes 62, which are supplied with steam from tho pans below; b³ is a scraper
attached to b¹, which keeps the surface of the pipes free from incrustation, and
scrapes off the salt collecting in the pan into a hole b*, from which it is elevated by
the elevator L, and pass through the dryer I and down shoots ¿¹¹ or ¿¹³.
The pan is covered by a wooden lid lined with felt and metal and draining into
cistern c7.
The pan C rests on the brick work at c¹ and is warmed by the combustion
chamber P beneath it; c is a joint for admitting heated air from the pipe w³ into
the hot air jet pipes cs; c is the scraper scraping the sides and bottom of the pan
keyed on to vertical shaft b¹. The salt passes through a hole into elevator M, and by
trough m, j, into the dryer J, from which it is discharged at 14, or may be discharged
direct down without passing through the dryer; c are the gutters into which
the condensed water from the roof drains down pipe c into cistern c²; the steam
and hot air from this pan pass by a pipe through the coils 62 in pan B, or through a
portion of the coils in a³ in pans A and down into the cistern c'; C is supplied with
heated brine from pan B by the pipe 67 through the float box y, c, and feeds the
vacuum pan D by pipe y¹ and float box Y. There is a man-hole. The salt can be
discharged at ɲ™ª without passing through the dryer J.
The pan D is warmed at its side by spiral flues p'; it is provided with stuffing
boxes b and b, through which the vertical shaft b¹ passes. It is provided with
scrapers d³ and condensing gutters d, which connect with the condensed water coils
of a in pan A; it scrapes its salt into a hole d', from which it is elevated by the
screw N and discharged into the dryer H, whence after being dried it is discharged
into the store G. It is supplied with boiling brine from pan C by pipe y' through
float box Y, which keeps the brine at a proper level. The steam generated in this
pan passes by a pipe through a portion of the coils a³, pan A, and thence as con-
densed water into air receivers T, from which it escapes down a vacuum column ts.
It supplies boiling brine for the jets ea to the vacuum tables E, E, in chamber Ex.
There is a man-hole. Chambers Ex (and Ex) contains the tables E, E, beated by
the gases from flues p³, which pass through flues p³ (or may enter by flue Q
regulated by damper q*), and pass to the centre of the tables by flue q', heat the
dryers e¹, and pass round a spiral coil q² through flue g³ into flue p¹. The shaft a¹
passes through the centre of the tables and carries on its frame e', supported on
its outer edge by the wheel es, keyed on to shaft e³, and running round a rail on
the outer edge of the table e¹s. The frame carries a revolving scraper e carried in
bearings at es, to which is attached a bevel wheel e gearing with a wheel e³ on &
hollow tube, which is driven by another bevil wheel and shaft e through a stuffing
box el by a wheel e, b*.
It also carries a scraper e³ and a spray pipe e; to the lower portion of the frame is
attached a third scraper elo, which passes the salt down a dryer through an opening
in the centre of the table, as hereafter described, into the salt store F.
In place of bringing the flues q¹ under the tables I sometimes arrange them so
that scrapers with jets can be used at the top and bottom of each table. I some-
times fill chamber Ex with brine, covering one or both tables working in or
ex vacuo, scraping the salt into the store F, when I sometimes dispense with the
revolving scraper e². In this case I run the brine off by suitable pipes before
emptying the salt.
There are openings a, a, a, b, and a, c, above the tables, and a tap a, e, to admit
air. The supply of brine to the jets e, q, is regulated by the handle e, f, moved
from the gallery A, C. The steam from the tables E passes into the dome A, E,
where it is either condensed by the spray pipe a, c¹, in which case the condensed

page_text: water runs away by some of the coil pipes as through T, and down the Torrecellian
column t³, the air being exhausted by pipe a, e², in connection with T, or else the
steam is drawn through the coils a³, and so on to T; and the Torrecellian column,
which is what I prefer; A, E, has a stuffing box at a, et.
The glazed spy holes at a, a, a, b, a, d, and others, are cleaned by jets of air or
steam, as are most of the other spy holes about the apparatus.
F and F is the salt store for the vacuum tables E; it is supported on the
frame A, F, at f* and f³; it has a discharge valve f worked by a screw f'; it has
a man-hole at f and a pipe f³ fitted with the necessary valves for discharging
water or admitting steam; fx is a leveller attached to vertical shaft a¹. There is
a glazed spy hole at a³, and others.
I prefer constructing these stores to hold the results of a day's work, or else in
two parts, with a valve to be filled alternately.
G is the salt store for the vacuum pan D, it has a discharge valve g worked by g¹,
a inan-hole g³, a pipe with the necessary valves g³, for either draining water or
admitting steam, a glazed spy hole at a, d, and others, and a handle for admitting
air bit communicates with the dryer H by an opening, which is closed by
valve, by handle h" worked from the gallery A, C.
At the top of G there is a pipe and cock communicating with the chambers Ex
and Ex
I sometimes, with less advantage, pass salt dried from pan D into the salt store,
which may be filled or partially filled with brine. In this case when it becomes
sufficiently filled with salt the brine is drained off before the store is emptied,
suitable, cocks and handles being provided for the purpose.
I prefer constructing these stores to hold a day's work, or else in two parts, with
a valve to be filled alternately.
The dryer H is screwed to the top of the store G, and is a circular box with a
sloping roof and bottom, the sides and bottom surrounded by a steam or hot-air
jacket h. It contains a series of shelves h, along the sides and ledges ³, along the
bottom; down its centre passes a vertical shaft h, carried on bearings at the bottom,
and passing through a stuffing box at the top, turned by wheel 222, to which is
attached a hopper n, h, with a spout n, h', a series of shelf scrapers h¹ and h, and
a series of lead scrapers h". The hopper n, h, is supplied by the screw N with salt,
which the spout n, h', delivers on the first shelf h. The salt is scraped from each
shelf by a scraper h¹ into the cup h² beneath it, which lays it on the next shelf;
the bottom scrapers h³ pass the salt along the ledges from the circumference to
the centre, where it falls through a hole h, g, into the salt store beneath. The
scrapers are so arranged that the salt remains on each shelf during a nearly
complete revolution of the shaft h before being scraped to the shelf below, the object
being to thoroughly turn over and dry it:
The dryer is fed at the top by the screw N into the hopper n, h. There are
glazed spy holes, one at h³.
I is the vertical shelf dryer, it consists of a series of shelves is fixed on the out-
side of a chimney, or of the down comer R, and enclosed in a revolving cylinder i
fitted with a circular hopper i, divided into compartments furnished with holes for
dribbling the salt on to the top shelf is, of the scrapers and ledges 10 for passing
the salt successively from shelf to shelf, the scrapers being so arranged that the salt
remains during nearly an entire revolution of the cylinder i on each shelf before
being passed to the next, and so on till it is discharged into an annular cup
the last shelf scraper, and from thence is passed by scraper 12 into the hopper iis
down the pipe . Two rings are attached to the cylinder i carrying rails i and
racks ; the lower ring is supported at its base on wheels 2, the upper ring is
kept in position by wheels i carried on bracket i³. It is made to revolve by
shaft z, i, and spur wheels i8.
by
It is heated by the spent gases from the furnace passing to S, and by heated air
admitted from beneath from the jacket of the down comer; it is sometimes heated
by a flue communicating with the combustion chamber P. It dries the salt of

page_text: pans A, A, and B; it is fed with salt by pipe k, i, from elevators K, K, and L, and
discharges by pipe into waggons; when not in use suitable valves pass the salt
down k, i, direct to i¹ and the waggons.
J is a duplicate vertical dryer round R, drying the salt of pan C, discharging
down into waggons. It is fed from elevator M by pipe m, j.
K and K is a salt elevator for pans A, fed by holes a from pans A and A
and delivering down pipes k¹ to the dryers or shoots 4. It is constructed like the
elevator H with draining buckets, and is driven by a revolving shaft 215.
Land M are similar to K, L, emptying pan B, and driven by shaft 217, discharging
into k¹ or into a separate shoot 1 (middle arch) M, emptying pan C, and driven by
shaft 2¹8, and discharging by pipe m, j, into dryer J, or direct to shoot (right
arch).
N is the screw for conveying the salt from the vacuum pan D to the dryer H.
The lower end of it communicates by a box d with pan D, the upper end with
revolving hopper n, h, (Figure 9). The interior of the casing is provided with
grooves or ledges for assisting the passage of the salt. The screw shaft is driven
by a bevel wheel and passes through a stuffing box. In place of using a screw I
sometimes use an elevator or travelling band.
O are the furnaces provided with doors o, blowers o³, and ash doors o³. They
may be self feeding; their flames escape by openings o, and meet in combustion
chamber P.
P is the combustion chamber under pan C. It is surrounded by openings p¹
leading into spiral flues p³. There are openings fitted with dampers communicating
direct with the down comers R and R There is an opening into flue q fitted
with a damper q* in direct connection with the vacuum table. It is fitted with a
steam pipe for blowing steam upon the bottom of the pan C to prevent the
formation of pan scale, and to cool it and the flues when they become over heated.
It has various openings and jet pipes for the admission of steam, air, etc., for im-
proving combustion. It is provided with a small door for entering the chamber,
and a pillar p³ supporting the pan above passes through its centre. It is traversed
by the hot-air pipes W.
The heated gases from this chamber usually pass by openings p¹, round the pan
C, by the spiral flues p³, out by the opening p³, into the opening 9 and flue q', round
the vacuum table, returning by flue q³ and q³ to flues p' round the vacuum pan D.
A direct communication is however arranged between flues p³ and p, and it,
together with flue p³ and flue q¹, are fitted with dampers.
Qis a direct flue leading from combustion chamber P to film tables E, and fitted
with a damper q*. It communicates with the combustion chamber at p, q. The
course of the flue q' is from Q to the centre of table E, where it first passes round
the centre of the table and returns by flues q², q³ to the flues p'; q³, also commu-
nicates with the down comers R. Thero is a damper in q¹, and between q³ and R,
and between flues q³ and p*.
R is the down comer fitted with an auxiliary chimney R¹ and damper r, and
connected with flue S. It communicates with flues p³, p¹, p², and q³, with suitable
dampers. It passes through the vertical dryer I and is enclosed below the dryer by
a brickwork jacket for heating air for dryer I, which enters at i, 17, x,
and passes
out by pipe 20, communicating with the auxiliary chimney R¹.
R is a duplicate, and heats air for J.
S is a flue, drawing off the furnace gases from the down comer R and R
jet or otherwise, and communicating with another furnace pan or chimney.
.
by &
Tx are the air receivers placed on a platform between A and A They are
fitted with escape valves, and communicate by suitable pipes and cocks with the
condensing and hot water coils in pans A, A, and B, chamber Ex, G, and the top
of pan D, with a vacuum column or columns 12 by the pipe n¹, with the vacuum
receiver u, and the exhaust engine U, which exhausts their air, while the column (²
exhausts their water.
Taps are provided so that Tx can alone be connected with the condensing coils

page_text: connecting with pan D, while T connects with the coils connecting with E*, and E*,
and with b; T and T* are both furnished with vacuum columns t¹².
U is the exhaust air pump and engine fitted with expansion and side valves. It
exhausts the receiver u. Its speed is regulated by a vacuum regulator like t, u,
(Figure 2, Sheet 2) placed on receiver u, fitted with an escape valve, and drain
pipe, and cock. It is supplied with steam from a boiler or from pan D and chamber
Ex, and blows its exhaust steam into the various jets or into a pipe * connecting
with the coils 64 and a³.
V is the pump for compressing air into receiver v, which is fitted with an inlet
valve and drain pipe; V is driven by speed wheels from the engine Z; v forces
heated air into the pan C by jets in the radiating arms c³, which connect by pipes
1.2, with the boxes, which circulate it in the pipes W, letting it escape highly
heated by pipe W1,2, and 3,
3, up the pillar p³, through the joint c², into the radiating
A valve is placed in pipe w¹ to prevent the return of air or water.
pipes V1 and 2
are taken up above the level of the pan to avoid the accident of
brine getting into the tubes W.
arms c
The
The tubes W traverse the combustion chamber P, and heat the air on its passage
from the pump V to the pan C. The box is supported on rollers to allow for the
expansion and contraction of the tubes W. The front plates of boxes and are
removerable for the purpose of cleaning the tubes W. These tubes are arranged for
heating air or gas, but I sometimes also introduce steam, or use them for steam alone
by a pipe in connection with the boiler.
X is the pump for supplying brine to systems A, A. x is the pump for emptying
the well, into which the tube from the vacuum column t, u, discharges. Both these
pumps, together with v, are driven by speed wheels from the engine Z, or may be
driven independently of each other.
In the place of these pumps U, V, X, X¹, I sometimes use pumps of a different
construction, or jet blowers, exhausters, etc.
Y is the float box for pan D, Figure 17.
It connects with pan C by pipe y¹, regulated by a float y³, which rises and fulls
with the level of the brine in pipe y, opening and closing orifices in the same; y¹ is
a handle attached to the float ; it passes through a stuffing box yo, and an indicator
is placed at yº.
The handle is to prevent the float from sticking through incrustation Y; a is
constructed on the same principle, bringing brine by pipe 67 to C, only the brine
pipe enters at the top instead of the bottom of the float box.
Z is the engine, driving the pumps X, X, and V, and driving the gearing by
shaft Z. Its speed may be regulated by a handle a, z, x, placed on gallery A, A,
and A, C. It is fitted with expansion valves and governors, and discharges its steam
into the pipe Z*, which is connected with the coils b* and a³. It can however discharge
its steam into the various jets about the apparatus.
It is supplied with steam from the chambers E, x, and pan D, but may be worked
direct from the boiler. ¹ is a vertical shaft turned by engine Z; Z' turns shaft 2+
by bevel wheels 2, 3; turns cross shaft 27 by bevel wheels and 26, the latter
being fitted with a clutch box to throw it out of gear; 7 has at its two ends bevel
wheels, which turn bevel wheels 20, keyed to a¹ and a¹ of the first set of pans.
Shaft b' of the second set of pans is turned by bevel wheels 21 in gear with 210
keyed to shaft
Although I prefer this arrangement, I sometimes arrange to have the scrapers in
the various pans move at different speeds, in which case I employ tubular shafts
revolving round shafts a¹ and b₁, with stuffing boxes driven by wheels placed under
wheels and 11, and actuated by additional bevel wheels on shaft z' and
The elevators K are both driven by a revolving shaft 21, on which is keyed
wheel in gear with the screw affixed to the shaft 2. Elevator L is turned by
a small cross shaft 217 in gear with 2x keyed to shaft 21.
Elevator M is turned by a revolving shaft 213, which revolves in bearings on the.

page_text: down comers J and T, passing immediately under the cross shaft 217, and is turned
by a screw 212 also on shaft, Figure 3.
Dryers I and J are also turned by shaft 213, which has attached to it a clutch box,
turning 1x, in gear with the bevel wheel z, i, x, keyed to the vertical shaft z, i, in
gear with the dryer by spur wheels keyed to it. The dryer H and screw N are
both turned by a screw wheel 210 in gear with the screw 218 on the cross shaft 27; 219 is
keyed to vertical shaft 220, turning wheel zal in gear with z keyed to the dryer
shaft h. On the lower side of z is a bevel wheel in gear with 2³, turning the
screw N.
Arrangement is made for throwing the wheel out of gear.
The wheel e (Figure 8) is turned by multiplying gearing or belt from wheel z, c,
keyed to cross shaft 27.
The brine circulates as follows:-
The pans A and A are supplied from the brine head or from pump X, and the
brine is warmed by condensing steam and condensed water.
It then passes into pan B, where it is further warmed in the same way, and
heated by surrounding flues p³.
From this pan it passes into pan C, where it is boiled and concentrated by the
combustion chamber, by surrounding flues, and by hot air blown into it. From this
pan it is drawn by the vacuum into pan D, where it is boiled in vacuo, and further
concentrated by the heat from below and the flues at the side. From this pan it
passes to the jet pipes in chamber E, X, also in vacuo, and is thrown on the heated
surface of the table, to be aftorwards scraped off as salt into the dryer, and thence
into the salt store. Although this is the arrangement I prefer, the jets may be
supplied with brine from any of the pans, and the pans not supplying the same may
be either boiled separately, or their brine may be run direct into other pans or
crystallising vessels which I sometimes heat. I sometimes force the brine into the
jets by a pump or steam jet.
The salt from pans A passes through dryer I, and down the shoot ix, into
waggons, or may pass into waggons without going through the dryer. The salt
froin pan B may be either passed through the same dryer and trough, or down a
separate shoot ¹ into waggons. The salt from pan C is passed through the dryer J
and into waggons by the shoot 14, or may be passed direct to the shoot j¹ without
going through the dryer. The salt from pan D is passed through the dryer H, and
stored in G.
The steam arising from pan D and chambers EX, EX, gives off its latent heat
to the coils in pans A and A, sometimes supplying steam for the engines before
so doing. In this arrangement I prefer to place the engines near the upper pans.
The waste water arising from condensation passes into receivers T, and down the
vacuum column. The condensed water from the roof of pan D passes through the
lower coils in the pans A, A, and down the vacuum column. The condensed water
from the roof of pan C passes through lower coils in A and A into cistern c', which
supplies the boiler with condensed water, any surplus water warming brine in
another pan by tubes, jackets, or otherwise. The steam and hot air from pan C are
passed through the coils in pan B and a portion of the coils in pans A and A. The
water from the vacuum column is used with suitable arrangements where the fall
permits for driving hydraulic machinery.
The gases from the furnace and combustion chamber pass under the bottom and
round the flues of pan C, round the vacuum tables in chambers E, X, round pan D
and pan B to the down comers R, drying the salt in I and J, into flue S, and thence
to a chimney or over a furnace, like Q (Fig. 2, Sheet 1), and under another pan,
or over a surface heating pan, over which I construct a drying floor, or it may pass
up a chimney at the end of S.
The heat of the tables may be regulated by the damper in the flue Q, which may
be worked independently of the gases passing round pan C, which in this case heat
pan C, D, and B before passing into the down comer.

page_text: 1 open a damper between p" (the lower) and p (the upper) set of spiral flues P.
I light fires in furnaces 0, 0, and when they have sufficiently burnt up put on the
blast from blowers o².
I turn on exhaust jet in flue S, and close damper v.
I throw the wheel out of gear. I start the engine Z.
I open damper in flue p³, admitting the heat to tables in the chambers EX, E X.
I close valves f,f¹, and g¹ in salt stores.
I close valve 10, shutting off the store G from the dryer H.
I shut off communication between T X and T.
I shut off communication between T X and the coils.
I open communication between T and the coils.
I start the air pump, exhausting the air from TX, pan D, screw N, and dryer H,
and start the vacuum column when pan d is started.
I open communication between Gand EX, E X, and blow G full of steam, driving
the air into E X, EX, which finds its way round the coils and out of the escape valve
in T, and close the tap between G and EX, steam still being on.
I heat the dryer H.
I blow EX and EX full of steam, driving the air into the coils and out at T.
open communication between G and EX, EX. As the steam passes down the
coils into T it condenses, and when the air has done escaping from T I shut off the
steam from the stores G and chambers EX, EX, drain any condensed water that
may have accumulated in them through pipes g³ and ƒ³.
I now start the second vacuum column, and cautiously open communication
between T and the air pumps, and exhaust the air from T, which draws the remaining
steam from chambers E X, EX, and G through the tubes, producing a vacuum in
the three chambers.
When the vacuum is established throughout the apparatus I close communication
between EX and G and between G and T, and open the valve p¹º.
When the tables are sufficiently heated I put wheel Z° into gear, and start the
shafts A 1, dryer H, and screw N.
I now turn the brine on to the vacuum tables by handles e, f, when the apparatus
is started.
The store G may at any time be emptied by stopping the screw, closing valve h¹º,
admitting air by 612, and letting the salt discharge into a waggon by opening 6'. To
start it again f¹ is closed, g is filled with steam, which is cautiously withdrawn into
some of the coils in pans A, A.

page_text: When a vacuum has been established valve 10 is opened, the screw started, and
the store commences refilling. This store, together with pan D, can be worked
quite independently of the tables in tables EX, E X.
When the stores F and F are filled with salt (which is at the end of the day's
work) air is admitted into them by handles f, and the vacuum destroyed, when the
salt can be emptied into wagons by opening f¹. They are started again as pre-
viously described, and are worked quite independently of pan D and salt store G.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I claim as respects that
portion of my Invention which is illustrated by Sheets 1 and 2 of the Drawings,―
First. The construction of apparatus for evaporating brine with a cylinder placed
horizontally and heated externally, such cylinder being caused to revolve whilst its
inner surface is moistened with brine and the salt removed by scrapers, substantially
as described.
Second. The application of a steam jet to prevent the heat of the furnace from
impinging directly upon the pan, substantially as described.
Third. The several improvements in apparatus for evaporating brine, and producing
salt, substantially as described.
I claim as respects that further portion of my Invention, which is illustrated by
Sheet 3 of the Drawings,
Fourth. The construction of apparatus for evaporating brine with a pan heated
by fire beneath, and by hot air blown in, and with a coil or receiver, into which the
steam generated in the pan passes, together with the hot air to heat brine in contact
with the exterior of such coil or receiver, substantially as described.
Fifth. The construction of apparatus for evaporating brine with a vacuum pan,
and with a coil or receiver for receiving the steam generated in the pan, and heating
brine, and with scraping apparatus to remove the salt as it is formed, substantially
as described.
Sixth. The construction of apparatus for evaporating brine with heated tables
and scrapers, removing the salt from the surface of the table, and delivering it through
a hole in the table into a receiver below, substantially as described.
Seventh. The construction of apparatus for drying the salt, substantially as
described.
Eeighth. The several improvements in apparatus for producing salt, substantially
as described.
In witness whereof, I, the said John Howard Worthington Biggs, have
hereunto set my hand and seal, this Eighth day of May, in the year of our
Lord One thousand eight hundred and seventy-seven.
J. H. W. BIGGS. (L.S.)