APPARATUS FOR MAKING RED PHOSPHORUS

APPAREIL POUR L'OBTENTION DE PHOSPHORE ROUGE

English Abstract

APPARATUS FOR MAKING RED PHOSPHORUS
ABSTRACT OF THE DISCLOSURE:
The disclosure relates to an apparatus for making red
phosphorus by subjecting molten yellow phosphorus to a
thermal conversion reaction in a drum packed with ball-
shaped material and provided with a first and second rotat-
ably mounted shafts, of which at least one is a hollow
shaft.
More particularly, a rotatable feed duct (5, 6) is
tightly connected to each of first hollow shaft (2) and
second hollow shaft (3); a floor-anchored torque-support-
ing means (7) is secured to each of the two rotatable
feed ducts (5, 6); an open-ended stationary tube (8) is
passed through rotatable feed duct (5) and also through
the first hollow shaft (2), the tube terminating with its
open end at a point where the first hollow shaft (2)
opens into the drum (1); a second unilaterally closed
stationary tube (12) is passed through the second rotat-
able feed duct (6) and also through the said second
hollow shaft (3), the tube terminating with its closed
end at a point where the second hollow shaft (3) opens
into the said drum (1); and a pressure-receiving means
(15) is mounted in a lateral opening provided in said
second rotatable feed duct (6).

Claims

The embodiments of the invention in which an exclusive
property or privilege is claimed are defined as follows:
WE CLAIM
1. An apparatus for making red phosphorus by subjecting
molten yellow phosphorus to a thermal conversion reac-
tion, which comprises a drum, the drum being filled
with ball-shaped material and provided with a first
and second rotatably mounted hollow shafts; a first
rotatable feed duct and a second rotatable feed duct
being tightly connected to said first hollow shaft
and second hollow shaft, respectively;a floor-anchored
torque-supporting means being secured to each of the
two rotatable feed ducts; a first open-ended stationary
tube being passed through said first rotatable feed
duct and also through the said first hollow shaft,
terminating with its open end at a point where the said
first hollow shaft opens into the said drum;a second
unilaterally closed stationary tube being passed through
the said second rotatable feed duct and also through
the said second hollow shaft, terminating with its
closed end at a point where the said second hollow
shaft opens into the said drum; and a pressure-receiv-
ing means being mounted in a lateral opening provided
in said second rotatable feed duct.
2. The apparatus as claimed in claim 1, wherein the said
first tube has a ball valve secured to its end protrud-
ing outwardly from the said first rotatable feed duct
and the said first hollow shaft.

3. The apparatus as claimed in claim 2, wherein a yellow
phosphorus feed pipe opens into the said first tube
at a point lying between the said first rotatable feed
duct and the said ball valve.
4. The apparatus as claimed in claim 3, wherein a bellows
is provided in the said feed pipe.
5. The apparatus as claimed in claim 1, wherein the said
unilaterally closed stationary tube has a terminal
head secured to its open end protruding outwardly from
the said second rotatable feed duct.
6. The apparatus as claimed in claim 5, wherein the said
terminal head is provided with a line running to a
temperature-indicating means TR.
7. The apparatus as claimed in claim 1, wherein the
pressure-receiving means is provided with a line runn-
ing to a pressure-indicating means PR.

Description

z~
HOE 83/H 007
This invention relates to an apparatus for making red
phosphorus by subjecting molten yellow phosphorus to a ther-
mal conversion reaction, the apparatus including a drum
filled with ball-shaped material and provided with a plu-
rality o~ rotatably mounted shafts, o~ which at least oneis a hollow shaft.
US-PS 4 330 504 discloses an apparatus for making red
phosphorus including a heatable drum which is filled with
ball-shaped material and provided with two rotatably mounted
shafts of which at least one is a hollow shaft. Secured to the
hollow sha~t is a yellow phcsphorus dosing ~eeder comprised of a
stationary angled yellow phosphorus feed pipe having one
o~ its arms surrounded by a rotatable double-walled tubular
structure which is connected to a ball mill. The said arm
and rotatable tubular structure are tightly connected to-
gether by means of a stuffing box. Disposed near that end
of the rotatable tubular structure which is nearer the
rotatable drum is a valve which can be actuated, closed
and opened by means of a dosing rod that is passed through
the rotatable tubular structure and said arm of the feed
pipe7 and a pistonO A portion of the rotatable tubular
structure is comprised of two bellows which are spaced
apart from one another and arranged concentrically with re-
spect to the dosing rod~ compensating the strokes o~ the
dosing rod.
German Speoification DE-OS 3 113 705 describes a de-
~ice for metering liquid yellow phosphorus into a rotating
ball mill for producing red phosphorus therein. The device
includes a stationary outer tubular structure surrounding
3Q an inner tubular structure rotatably mounted therein.
,.

-`` ` 31 2~7~3
valve having a valve rod associated with it is disposed
within the i~ner tubular structure near it end close to
the ball mill. A plug provided with a central bore receiving
the val~e rod is installed within the inner tubular structure
near its end remote from the ball mlll. Inside the in~er tu-
bular structure, a portion o~ the valve rod is surrounded
by a bellows tightly conneoted to the plug and valve rod.
The prior art de~ice ~irst d~scussed hereinabove and
its dosing feeder are not fully satisfactory, however, in-
asmuch as the bellows are subject to dilatation and compres-
sion and also torsion stresses during operation. This natu-
rally affects the service life of the device considerably
and, in the event of the i~ner bellows becoming defective,
it is even possible that yellow phosphorus and warm water
mix together which is undesirable.
~ The metering device last discussed hereinabove is very
expe~sive in design and construction, yet problematic ~or
lack of perfect tightness because o~ the many radial sha t
packing rings and stuffing boxes used in it.
The present invent~on now provides an apparatus ~or
making red phosphorus by subjecting molten yellow phosphorus
to a thermal con~ersion reaction in a drum packed with ball-
shaped material and provided with rotatably mounted hollow
shaXts, wherein a relatively simple device is used for in-
troducing the yellow phosphorus into the drum~ and wherein
water and yellow phosphorus are substantially not liable to
mix together,
To this end, the invention provides for a rotatable
feed duct to be tightly connected to each of the first and
second hollow sha~ts; for a ~loor-anchored torque-supporting

9788
means to be secured to each o~ the two rotatable ~eed
ducts 9 for a first stationary open-ended tube to b~ passed
through the ~irst rotatable ~eed duct and also through the
first hollow shaft, the tube terminating with its open end
at a point where the first hollow sha~t opens into the
drum; for a second stationary unilaterally closed tube to
be passed through the second rotatable feed duct and also
through th~ second hollow sha~t, the tube terminating with
its closed end at a point where the second hollow shaft
opens into the drum; and for a pressure-receiving means to
be mounted in a lateral opening pro~ided in the second ro~
tatable feed duc~.
Further preferred ~eatures o~ the invention provide:
a) for the first tube to have a ball valve secured to
its end protruding outwardly ~rom the first rotatable
feed duct and the first hollow shaft;
b) ~or a yellow phosphorus ~eed pipe to open into the
first tube at a point lying between the first rota~
table feed duct and the ball valve;
c) for a bellows to be provided in the feed pipe;
d) ~or the unilaterally closed tube to have a terminal
head secured to its open end protruding outwardly ~rom
the second rotatable feed duct;
e) for the terminal head to be provided with a line running
to a temperature-indicating means TR; and
f) for a pressure-receiving means to be provided with a line
runni~g to a pressure-indicating means PR.
In the apparatus of this invention, use can be made of
standard rotatable feed ducts, such as those disclosed? e~g.
in DE~PS 1 164 768.
As regards the stationary tuDe which is passed through

2~ 38
the rotatable feed duct and first hollow shaft and used
for the introduction of yellow phosphorus into the drum,
it is necessary for it to be cleaned after some time of
operation. To this end, the yellow phosphorus feed pipe
is closed, the ball valve is opened ~ter release of
pressure, and a rod having cleaning tools secured to it
is pushed into and through the pipe,
By the use of a rotatable feed duct provided with a
stationary unilaterally closed tube, it is made possibl~
for the temperature and pressure prevailing inside the
rotating drum to be readily tested by remote control.
A form of apparatus of this invention is shown dia-
grammatically and i~ section in the accompanying drawing.
With re~erence thereto:
A drum 1 is pro~ided with a first hollow shaft 2 and
a second hollow shaft 3 and packed with iron balls 4.
Tightly passed through the hollow shafts (2, 3) are rota
table feed ducts (5, 6) each of which is provided with a
torque-supporting means 7 anchored to the floor.
A stationary open-ended tube 8 is passed through ro~
tatable feed duct 5 and also through the first hollow
shaft 2, tube 8 terminating with its open end at a point
where the first hollow shaft 2 opens into drum 1. A ball
valve 9 is secured to the opposite end of tube 8, protrud
ing outwardly from rotatable feed duct 5. A yellow phospho-
rus ~eed pipe 10 pro~ided with a bellows 11 opens into tube
8 at a point lying between rotatable feed duct 5 and ball
Yalve 9.
A stationary unilaterally closed tube 12 is passed
through rotatable feed duct 6 and al50 through the second
hollow sha~t 3, tube 12 terminating with its closed end at

~2~78~
a point where the second hollow sha~t 3 opens into
drum 10 The unilaterally clos~d tube 12 is used as a
pocket receiving a thermocouple. A terminal head 1~
provided with a line 14 running to ~ tempera~ure-in-
dicating means TR is secured to the open end of tube 12,protruding outwardly from rotatable feed duot 6.
Mounted in an opening provided in rotatable feed duct 6,
running perpendicularly with respect to u~ilaterally
closed tube 12, is a pressure receiving means 15. The
pressure prevailing in drum 1 is communicated to the
pressure-receiving m~ans 15 via the annular chamber
formed betweer~ tube 12 on the one hand and the central
hollow space in rotatable feed duct 6 and the second
hollow shaft ~ on the other hand. The pressure-recei~ing
means 15 is provided with a line 16 running to a pressure-
indicating means PRo
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