IMPROVEMENTS IN APPARATUS FOR EVAPORATING WATER OR OTHER FLUIDS, OR FOR DRYING SUBSTANCES CON- TAINING WATER
Year: 1879

page_text: LETTERS PATENT to Edmund Edwards, of the Firm of Edwards and Company,
Patent Agents and Engineers, of 40, Southampton Buildings, in the County
of Middlesex, for the Invention of "IMPROVEMENTS IN APPARATUS FOR
EVAPORATING WATER OR OTHER FLUIDS, OR FOR DRYING SUBSTANCES CON-
TAINING WATER." A cominunication from abroad by Edouard Reyer, of
Vienna. in the Empire of Austria.
PROVISIONAL SPECIFICATION left by the said Edmund Edwards at the
Office of the Commissioners of Patents on the 19th July 1879.
"5
EDMUND EDWARDS, of the Firm of Edwards and Company, Patent Agents and
IMPROVE
Engineers, of 40, Southampton Buildings, in the County of Middlesex.
MENTS IN APPARATUS FOR EVAPORATING WATER OR OTHER FLUIDS, OR FOR DRYING
SUBSTANCES CONTAINING WATER." [A communication from abroad by Edouard
Reyer, of Vienna, in the Empire of Austria.]
This Invention relates to apparatus to be used for the purpose of evaporating by
heat water or other fluids, or for drying substances containing water by means of
heat. It consists of improved methods of constructing and arranging, such
apparatus.
The improved apparatus consists essentially of a series of stages or platforms
arranged round a central opening, in a manner similar to a winding staircase. The
central opening is preferably square in plan, and the stages or platforms which rise
gradually round it in steps are made hollow and double, into one of the spaces thus
formed being placed the substance to be dried or the fluid to be evaporated, and
into the other parallel space heated air or gas being made to pass from a furnace
connected to the lower end of the space, or forced or drawn through by exhaustion
or blast. By this arrangement a large heating and evaporating surface is obtained,
and the heat is applied very effectively, whilst the apparatus takes up but little
room.
In order to ensure sufficient ventilation in the space within which the drying or
evaporation takes place as described, the central space within the stairlike plat-
forms is closed both above and below, with the exception of a hole at the bottom
which is connected with a fan or other exhausting apparatus, and in the outer and

page_text: inner sides of the evaporating space holes are made, through which air is drawn
through the evaporating space and into the central space or chamber.
The air thus drawn through is first heated in a jacket, which surrounds-the
outer sides of the entire apparatus, this jacket being provided with a sufficient
number of holes or perforations through which the air enters.
The holes for ventilation, as described, should be larger or more numerous in the
lower than in the upper part of the evaporation space, the heat being greater and
the evaporation.more rapid in such lower part. One or more cocks or valves may
be used to regulate the evaporation. Apparatus constructed according to this
Invention may vary in the form and size of the several parts described, according
to the particular substance which is to be treated in it.
If a fluid is the substance to be treated or evaporated, the upper end of the
winding stair like evaporating space described is made to communicate by means
of an adjustable cock or valve with a tank or cistern, from which the fluid is
supplied, and the lower end of the evaporating space communicates with a pipe, the
lower end of which dips into a reservoir into which the fluid flows. The level of
the fluid in this last mentioned pipe will vary in proportion to the diminution of
pressure in the evaporating space. The vapour which collects in the central space
of the apparatus may be condensed in an adjoining condenser. The apparatus con-
structed as above described may be made of iron, clay, or other suitable material,
according to the substance which is to be operated on.
Where a fluid containing any crystallizable salt or substance is to be operated
on in the apparatus, such fluid should not be concentrated sufficiently for crystals
to be deposited, and the supply and admission of air must be regulated accordingly.
If, however, it is intended that such crystallization and deposit should take
place, two opposite outside walls of the apparatus must be made moveable,
or suspended on hinges, so that they can be readily opened or closed for the purpose
of removing the crystals or salts deposited in the evaporating space.
Where other substances than fluids are to be dried or baked in the apparatus,
the side of the apparatus must be made moveable in the same way, for the purpose
of filling, emptying, and cleaning the apparatus; and the upper and lower ends of
the evaporation space will simply be closed instead of being constructed in the
method last described.
Apparatus constructed according to this Invention may be heated advantageously
by the waste heat passing from smelting or other furnaces.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edmund Edwards in the Great Seal Patent Office on the 19th January
1880.
EDMUND EDWARDS, of the Firm of Edwards and Company, Patent Agents and
Engineers, of 40, Southampton Buildings, in the County of Middlesex. "IMPROVE-
MENTS IN APPARATUS FOR EVAPORATING WATER OR OTHER FLUIDS, OR FOR DRYING
SUBSTANCES CONTAINING WATER." A communication from abroad by Edouard
Reyer, of Vienna, in the Empire of Austria.
The object of this Invention is to construct a furnace or apparatus for evapo-
rating liquids and drying various substances in such a manner as to obtain extensive
drying or evaporating surface in a relatively small furnace, and the economical
application of the heat.
The Invention consists in a furnace wherein flues or spaces for heated air or
gases, and evaporating space, are arranged in spiral form one above the other, and
around a central ventilating and hot air flue; there is also a jacketted heating
space round the furnace, in which air is heated previous to passing over the
evaporating surface to the central flue, whereby a continuous circulation of hot air
is obtained to aid the evaporation and to carry off the vapours. The construction
and operation will be more particularly described with reference to the accom-
panying Drawing, wherein Figure 1 is a perspective view of the improved furnace
showing the construction;. Figure 4 is a vertical cross section of the same;
Figure 3 is a detail view; and Figure 2 is a section showing the furnace as con-
structed for evaporating liquids. Similar letters of reference indicate corresponding
parts. The stair furnace can be constructed square or round, and oval.
material of which the furnace is to be constructed may vary according to the
purposes for which the furnace is to be used; iron clad, china clay, and metal way
be used.
The
Referring to the accompanying Drawing, R is the vertical ventilating flue or
space, within the body of the furnace, which is formed by side portions L.
The body of the furnace is formed of slabs or plates W₁, Www, of
material supported by inner and outer walls, laid in such a manner as to form two
continuous spiral passages ascending a certain distance at each angle, or in the form
of stairs, whereby the intervening spaces extend horizontally at each side of the
flue R, and connect at the angles, the two spaces F and W thus formed being
continuous and separate from each other.
At the upper end the flue or space R will terminate in a flue or chimney, and at
the lower end will be connected directly with a combustion chamber, or a suction
or blast pump may be used to force the heated gases or other products of combus-
tion from a heating or smelting furnace through the space R. The ventilating
space F will be closed at the top, and connected at the bottom with a suction
pump; in the sides there are openings L, from the evaporating spaces W', W, to
allow ventilation from those spaces into the flue R, and these holes L should be of
larger area in the lower portion of the apparatus, as more evaporation takes place
in those portions.
Around the outside of the evaporator is a jacket formed by an exterior wall of
suitable materials, through which wall there are openings Z, which permit air to
pass into the jacket and across the evaporating spaces W to the escape openings L,
the air being heated in its passage through the jacket.
By these means a continuous ventilation is maintained, the vapours are carried
off rapidly, and the heated air assists the evaporation.
Suitable cocks or valves will be provided to regulate the ventilation according
to the material under treatment, and a condensing vessel may be used to condense
the vapours.

page_text: For evaporation of liquids it is preferred to construct the apparatus as shewn in
Figures 2 and 3, and the top of the evaporation tunnels, as shewn by Figure 2,
will be formed as a vessel GG, from which-the-fluid-runs-through-the-cock-N-to-
-the evaporating space W, and then down the spiral or stair like tunnel.
The lower end of the tunnel will terminate in a vertical tube, and empty into a
receptacle for receiving the liquid, the tube G' dipping into the liquid, which will
stand at a level varying according to the pressure.
The steps of the tunnel will be made of china, clay, or metal, according to the
quality of the liquid, and will be fitted together, as shewn by Figure 3. The liquid
should not be concentrated to crystallization on the evaporator, and the ventilation
and heat should be regulated to prevent such action; but if the. fluid be of a
character likely to separate into solid parts, then two opposite outside walls of
the furnace must be fitted with moveable or hinging gates to give access to the
spaces W, W, for cleaning.
In an evaporator of this construction the operation will be rapid, and there will
be great economy of heat; the cleaning and repairing required may also be
readily effected.
A furnace for drying or baking may be constructed in the same manner, and
fitted with moveable doors in the sides for the purpose of filling, emptying, and
cleaning.
Having now described the Invention, and the manner in which it is to be per-
formed, I claim as new, and desire to secure by Letters Patent:-
1st. The improved evaporating and drying furnace, wherein the flues and evapo-
rating spaces are constructed and arranged one above the other in a continuous
spiral or stair like form, substantially as described and shown, and for the purposes
set forth.
2nd. In evaporating and drying furnaces the construction and arrangement of
the slabs or plate in continuous lines of spiral or stair like form, whereby the con-
tinuous lines of passages and central flue R are produced, substantially as and for
the purposes specified.
3rd. The improved evaporating or drying furnace constructed with the con-
tinuous spiral passages of central flue and outer jacket, with the ventilating openings,
substantially as and for the purposes specified.
4th. In combination with an evaporating and drying furnace constructed with
the spiral passages, the vessel and cock, substantially as and for the purposes
specified.
In witness whereof, I, the said Edmund Edwards, have hereunto set my hand
and seal, this 15th day of January, in the year of our Lord One
thousand eight hundred and eighty.