An Improved Method of Conditioning Textile Fibres, and Apparatus therefor.
Year: 1893

page_text: Date of Application, 17th May, 1893-Accepted, 14th Oct., 1893
COMPLETE SPECIFICATION.
An Improved Method of Conditioning Textile Fibres, and Apparatus
therefor.
I, WILLY SAULMANN of 26B, Potsdamerstrasse Berlin, in the Empire of
Germany, Chemical Student, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
In the methods of conditioning textile fibres as heretofore employed the materials
to be dried are either placed in drying vessels and hot air is forced or drawn through
these vessels, or else the drying vessels are heated from the outside, heating the
fibres and evaporating the moisture contained therein, while cold air taken directly
from the atmosphere is forced through the drying vessels, thereby volatilizing the
evaporated moisture. All these methods have defects which render a rational and
perfect working impossible and which are explained as follows. For following the
process taking place in the apparatus it is customary in practice to weigh the fibres
before the drying, that is to say in the moist state, and to do the same on the
termination of the drying. This weighing of the fibres has heretofore been caused
to take place at a temperature at which the dried fibres cannot take up the moisture
contained in the atmospheric air. This temperature is however rather high and
fluctuates according to the condition of some fibres between 105 and 120 degrees.
It will be readily seen with what difficulties the weighings take place and how
inaccurate they are. This however is occasioned by the necessity of removing the
fibres for weighing from the drying vessel after the drying. A further and very
great defect of the methods heretofore used consists in conducting air taken directly
from the atmosphere round the heated fibres; that therefore a perfect drying could
never take place is proved, considering that the moisture contained in the
atmospheric air amounts on an average to 8
Even by heating this air the
moisture could not be removed, as it was always carried away in the form of steam
and moistened the fibres again.
per cent.
Having regard to these defects, the apparatus hereinafter described has been
constructed which is represented in the accompanying drawings in which
Figure 1 is a side elevation of the improved apparatus and
Figure 2 is a plan of the same.
In a box / made of non-conducting material are arranged the drying drums n².
These drums n', of which there are four in the apparatus shown, are adapted to be
entirely shut off from the outside by two cocks teach, and to be readily included in
and cut out from the apparatus, inasmuch as they are simply screwed in with nuts u,
after the loosening of which the drying drums n¹ can be taken out. By the afore-
said nuts u the drying drums are included in the dry air pipe 9 which extends into
the box / surrounding the drying vessel n' and which according to the number of
drying vessels is divided into as many branch pipes.
As it is sometimes not necessary to fill all the drums with fibres the quantity of
dry air, when the drum is empty, would have to pass through such a drum n¹
without doing work. For this reason I provide in the branch pipes, in front and
behind the drum, cocks t by which any desired drum may be excluded from the
dry air pipe.
The pipes adjoining the other end of the drums n¹ serve for conducting away the
dry air and unite again like the admission pipe to form a single discharge pipe
which leads to a fan the object of which will hereinafter be explained. The box h
surrounding the drying vessels is itself heated by a source of heat i so that the
drying drums are always heated from the outside.
In the present method the dry air current is however not taken as heretofore

page_text: directly from the atmosphere, heated and then conducted through the drying
vessels, but the air is dried prior to the heating in towers c which are filled with
hygroscopic materials.
The air passes from the atmosphere through pipe a provided with a cock b, into
one of the two drying towers c shown on the left, through the hygroscopic material
contained therein and is here dried. The apparatus is provided with two drying
towers, only one of which is always in action, while the other is charged with fresh
hygroscopic material. The dried air is drawn from the upper part of the tower c
through pipe d and passes through an hygrometer n by which the working capacity
of the drying towers c may be controlled at any time.
The air which has already been dried now passes again through another drying
tower c which effects the complete drying and is then conducted to the heating
tower e in order to be heated to a temperature of from 110 to 130 degrees. The
air pipe is made in the form of a spiral d', passes down the heating tower e, then
up again and finally partly down the said heating tower and into the box h
surrounding the drums n', in which as above stated it is divided into branch
pipes.
The heating tower is heated by its own source of heat, the hot air circulating
round the spiral pipe and heating the previously dried current of air which passes
through the same. For exactly controlling the temperature of the dry air current a
thermometer m is included in the air pipe in front of the division into branch pipes,
whilst by means of a thermometer p, arranged in the air pipe after the union of the
discharge pipe, the temperature of the air passing out can be measured.
In order that the temperature of the hot air circulating round the drying drums n¹
may remain at a certain height (about 110 to 130 degrees) I arrange on the cover
of the box a thermometer I so that it extends into the heated space, while the
temperature can be read off on the graduated scale on the outside. In the
discharge pipe for the dry air is included a second hygrometer 7 by means of
which it is possible to determine exactly the moisture contained in the air passing
out and to see when the working process is terminated, as then the two
bygrometers n and 7 must indicate the same number. The air passing off does not
however act continually upon the hygrometer q, as it passes usually through a
branch piper and takes its way through the hygrometer only by the suitable
adjustment of the three cocks s.
The fan v provided at the end of the pipe has for its object to convey the air
through all the apparatus, which have hereinbefore been described.
The operation of the apparatus is as follows:
The drying drums are lifted from the apparatus, filled with the moist fibre
material, the two cocks arranged on the drums are closed, and the drums being full
are weighed. They are then included in the apparatus, the fan is set in motion
after opening the cocks t, and lighting the sources of heat and i. The dry hot
air current mingles with the moisture evaporated from the fibres by the source of
heat until these are themselves perfectly dry, which is ascertained by the
hygrometer 9 included in the discharge pipe. The process is then interrupted, the
drums are closed, allowed to cool and then taken from the apparatus and weighed
again together with the fibres contained therein.
As the weight of the drum is known or can be very easily determined after
emptying the same the weight of the fibres can be very accurately ascertained.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. A method of conditioning textile fibres characterized by the drying air
current being dried prior to the heating and passage through the drying drums in
apparatus specially constructed for this purpose and filled with hygroscopic
materials.
Second. For carrying out the method claimed in the first claim an apparatus

page_text: consisting of two drying towers used alternately in conjunction with a third tower,
consisting moreover of a heating tower d and a number of drying drums n' arranged
in a heated box h and which are connected with the aforesaid drying and heating
towers by a dry air pipe g through which apparatus a fan v arranged at the end of
the dry air pipe draws through the air, for the purpose above set forth.
Third. In the apparatus for conditioning textile fibres claimed in the second
claim an arrangement for enabling the drying drum n' to be easily exchanged and
hermetically closed for weighing before and after the drying.
Fourth. In the apparatus for conditioning textile fibres claimed in the second
claim the arrangement for enabling the working process in the apparatus itself to
be accurately controlled at any time by including hygrometers in the dry air pipe g
in front of and behind the drying drums.
Dated this 17th day of May 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.