Improved Means for Evaporating Substances and Reducing them to an Anhydrous Condition.
Year: 1899

page_text: Date of Application, 17th May, 1899
Complete Specification Left, 5th Feb., 1900-Accepted, 31st Mar., 1900
PROVISIONAL SPECIFICATION.
Improved Means for Evaporating Substances and Reducing them to an
Anhydrous Condition.
I, WILLIAM MATHER, of Salford Iron Works, Manchester, Engineer, do hereby
declare the nature of this invention to be as follows:-
In my application 26,981 of 1898 I have described a method of concentrating
solutions such as caustic soda by causing a film of such solution to be carried
over a heated roller, the effect being that the water is driven off, and that the
material may be concentrated until eventually a practically anhydrous solid sub-
stance is obtained.
Since the date of my said application I have discovered that the process may
be applied to many other substances which are capable of being spread in the
form of a film upon the surface of a heated cylinder in a liquid or semi-liquid
state. Amongst the many materials which may be so treated I may mention
borax, cyanide of potassium, and other substances which by the application of
heat become liquid or semi-liquid and are capable of being spread or taken up
in the form of a film on the surface of the cylinder, and which as their contained
water is evaporated become again solid and anhydrous upon such cylinder and
may be removed by a stripping doctor" as described in my previous specifi-
cation as applied to the cold or solidifying cylinder.
One form of apparatus which I judge will be most useful for this class of
work consists of a gas or otherwise heated cylinder as described in my previous
specification to which the material to be evaporated or rendered anhydrous is
fed through a suitable hopper or other device the material at the point of feed
being sufficiently hot to render it fluid or semi-fluid in order that it may be
delivered to the cylinder in the form of a film.
Certain substances while being evaporated give off gas, some of which not
infrequently remains for a certain time in the material in the form of unbroken
bubbles; to reduce these and produce a uniform and even film it will frequently
be desirable to have a spreading or compressing roller to which if necessary a
small stripping doctor may be applied to throw down any small particles
of material which may cling thereto.
"
A second stripping "doctor" is applied to the main cylinder for the purpose
of removing therefrom the anhydrous material as it is produced.
When treating substances likely to give off an objectionable vapor, or any
considerable amount of dust it is preferable to encase the apparatus and to pro-
vide a vapor outlet pipe in which one or more removable sieves or trays may
be inserted for the purpose of catching the dust and yet permitting the free
escape of the vapor. Where necessary the casing and the vapor outlet pipe may
he steam jacketed or otherwise enclosed so as to prevent any condensation of the
vapor or the escaping gas prior to leaving the machine.
1000
PHILIP M. JUSTICE,
55 & 56. Chancery Lane, London, Chartered Patent Agent.
For the Applicant.

page_text: Improved Means for Evaporating Substances and Reducing them to an
Anhydrous Condition.
I, WILLIAM MATHER,. of Salford Iron Works, Manchester, Engineer, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly. described and ascertained in and by the following
statement:-
-
In my application 26,981 of 1898. I have described a method of concentrating
solutions such as caustic soda by causing a film of such solution to be carried
over a heated roller, the effect being that the water is driven off, and that the
material may be concentrated until eventually a practically anhydrous solid sub-
stance is obtained.
Since the date of my said application I have discovered that the process may
be applied to many other substances which are capable of being spread in the
form of a film upon the surface of a heated cylinder in a liquid or semi-liquid
state. Amongst the many materials which may be so treated I may mention
borax, cyanide of potassium, and other substances which by the application of
heat become liquid or semi-liquid and are capable of being spread or taken up
in the form of a film on the surface of the cylinder, and which as their contained
water is evaporated become again solid and anhydrous upon such cylinder and
may be removed by a stripping doctor" as described in my previous specifi-
cation as applied to the cold or solidifying cylinder.
"
To clearly explain one form in which my invention may be carried out
reference is made to the accompanying drawings in which Fig. 1 is a sectional
elevation taken on line of Fig. 2 which is an end elevation the frame. and
some other parts being omitted.
In said drawings A represents a gas heated cylinder the gas and air being
admitted thereto by pipes B, C, and passing to burners D. The cylinder is
caused to revolve by gear E which also drives the spreading roll F. The cylinder
is surrounded by a casing G from which opens the vapour outlet H which may
be provided with removable sieves I to catch any of the material which may
become finely pulverized and carried away by the vapour arising from evaporation,
which vapour may further be treated for removing any fine particles of material
it may contain by being drawn off from the outlet H by an exhaust or otherwise
and condensed by any well known method, so as to leave the particles of material
in the water of condensation which may be afterwards utilized. The feed
hopper Jis provided with a slide K so that the quantity of material fed may be
regulated. The spreading roller F is shown as provided with a scraper or
"doctor" L which will throw down any particles of the material which might
adhere to the roller F and a second scraper or "doctor" M is provided for the
heated cylinder A. To enable the material treated to be withdrawn a slide
door N may be provided opening over a packing box or drum O.
The material at the point of feed from the hopper is in a liquid or semi-liquid
state and such material may be melted in the hopper or as it passes from the
hopper to the cylinder and such melting may be effected either by independently
heating the feed end of the hopper or by permitting it to come in contact with
the heated cylinder. In either case the liquid or semi-liquid material passes onto
the heated cylinder and when necessary under a spreading roll which reduces
it to a film of uniform thickness and expresses any bubbles or gases it may con-
tain while the heat of course rapidly removes the contained water and the material
is removed from cylinder A by stripping "doctor" M in a practically anhydrous
condition. The casing G and vapour outlet H may be provided with a steam or

page_text: other jacket P so as to prevent any condensation of the water or escaping gases
prior to their leaving the machine.
It will be obvious that different forms of heating and casing may be employed
and that the spreading roll may be omitted when treating such substances as
can be delivered from the hopper in a sufficiently uniform and even film or that
for other substances more than one spreading roll may be used and the position
and construction of the parts varied without departing from the scope of, the
invention.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what
I claim is
1. The improved means for evaporating substances and reducing them to an
anhydrous condition consisting of a feeding vessel adapted to feed a regulated
quantity of the liquid or semi-liquid substance, a heated cylinder for receiving
such feed and means for causing it to form a film thereon and a stripping doctor
for removing the anhydrous material from the cylinder and clear of the feeding
vessel substantially as described.
c
2. The improved means for evaporating substances and reducing them to an
anhydrous condition consisting of a combined melting and feeding vessel adapted
to melt and feed a regulated quantity of the liquid or semi-liquid substance in
the form of a film, a heated cylinder for receiving such film, a spreading roller
for distributing and compressing such film, a doctor working against said spread-
ing roller, and a stripping doctor for removing the anhydrous material from
the cylinder and clear of the feeding vessel substantially as described.
3. The improved apparatus for evaporating substances and reducing them to
an anhydrous condition substantially as described.
Dated this 31st day of January 1900.
G
PHILIP M. JUSTICE,
55 & 56, Chancery Lane, London, Chartered Patent Agent.
For the Applicant.