Process and Apparatus for Comminuting or Disintegrating Superphosphates.
Year: 1899

page_text: Date of Application, 2nd May, 1899-Accepted, 10th June, 1899
COMPLETE SPECIFICATION,
A Process and Apparatus for Comminuting or Disintegrating
Superphosphates.
A communication from abroad by CHEMISCHE FABRIK ACTIEN-GESELLSCHAFT, vorm
CARL SCHARFF & Co., of Nene Taschenstrasse 10, Breslau, in the German Empire. >
I, ALFRED GEORGE BROOKES, of 55 and 56, Chancery Lane, in the County of
London, Chartered Patent Agent, 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:-
This invention relates to a process by which superphosphates, immediately after,
leaving the "opening" or decomposing chambers, are comminuted and reduced.
to a readily dispersing dry powder.
By the methods employed hitherto, the superphosphate, on leaving the chambers.
referred to, was stored and, after being allowed to cool and dry, was reduced;
to a finely divided state in the disintegrator. The fresh material as it issues"
from the chamber is warm and soft; after cooling it acquires greater consistency.,
And it has been observed in this connection that the parts which thus acquired
increased solidity were those only, which, in the process of delivery, left the
chamber in the condition of lumps; whereas the fine or small portions did not
again cohere or cake, but retained the form of powder, notwithstanding the pres-
sure of the body of material or the prevailing high temperature. It is the
observation of this fact that has suggested the possibility of obtaining fresh
superphosphate in a fine and readily dispersing or loose condition the moment it
leaves the chamber wherein it has been produced. Accordingly the superphos
phate, while yet warm and inspissated, i.e. just as it is found in the chambers, is
cut up into thin layers which, on being exposed to the air, crumble into powder.
The methods of disintegration generally employed hitherto involving the use
of centrifugal machines, presses, rollers, squeezers, sieves or the like are not
applicable to fresh material direct, as the pressure developed in the course of the
operation of such appliances would tend to impart to them an oily adhesiveness or
greasiness."
"
;
Now this improved process based, as stated above, upon the property of super-
phosphate whereby it is capable of being cut into very thin layers in the condition
in which it leaves the chambers. In practice the process is carried out by placing
the superphosphate in a hopper, at the lower end of which a set of rapidly revolv-
ing cutters cut or rather scrape or shave off, thin sheets, from the issuing
superphosphate whereby a squeezing or compressing action in any shape or form
is avoided; while the thin sheets or laminae, as soon as severed, crumble away
into a fine powder or dust which by its extended surface promotes the evaporation
of the water contained in the material.
Apparatus suitable for the disintegration or comminution of superphosphate
in accordance with the above process is represented in the accompanying drawings,
in which
Fig. 1 is an elevation, and
Fig. 2 a plan; while
nation of one of the õutters emploved.

page_text: chambers to a hopper B, which passes it on to the cutter-barrel C whereby the
discharge orifice of the said hopper is closed.
The cutter barrel C comprises a disc 1) in the rear and a ring E in front.
Between the disc 1) and the ring E, the cutters F' are arranged almost tangentially
at predetermined distances apart being, in fact, screwed to the said disc and
ring; so that the cutters fitted to the periphery of the barrel form a species of
grating. The barrel receives motion from a shaft G and a strap pulley H. Below
the hopper are arranged the deflectors L1, L2, L3, L4 which serve to deliver the
material, as it is shaved off and crumbles to dust, into the tilting wagon or such
like receiver underneath.
The operation of the arrangement is as follows:―
The cutter-barrel C is set in rapid rotary motion by the strap pulley H, it being
essential that the speed of motion, thereby imparted to the cutters, should be so
determined as to be greater than the rate at which the material placed in the
hopper B descends; for the result of compliance with this condition will be, that
the whole of the material must in due course come in front of the cutters, thereby.
preventing any lumps of material, not divided by the cutters, from finding their
way through the apertures of the grating and into the tilting wagon M.
The distances left between the cutters must naturally depend upon the peripheral
speed of the barrel, and vice versa; the speed being such that there can form no
fat dises or similar pieces of material, but that the cutters, as they, each in turn,.
come into operation, exercise upon the material as it were a laminating or slicing
and shaving action; the thin laminae at once crumbling to powder, which effect is
additionally facilitated by the circumstance that, owing to the high degree of its
speed, the barrel has an exhausting or fan action, the wind or blast thereby pro-
duced impinging on the laminae and setting them in an eddying motion.
The powdered material is intercepted by the deflectors L', 12, L3, L4 and is by
them conducted in the direction of the arrows into the tilting wagon M.
The deflectors are pivotted to ribs such as R1, R2, R3, R, so that they may be
set at any requisite angle, the amplitude whereof is limited by pins s. The said
ribs are secured to arms T suspended from side carriers U, V.
The deflectors, more-over, have a further object to fulfil, in addition to the
one already mentioned, wiz. That of deflecting the wind, produced by the rapid
motion of the barrel, and the original direction of which is tangential,-into a
direction in which the particles of dust must drop into the tilting wagon; for
owing to the tangential course taken by the wind, a certain velocity is imparted
to the powder as it is scraped off; and it is for the purpose of screening the powder
from the effect of this impulse of the wind, which would tend to increase its
velocity as the speed of motion of the barrel becomes greater, that the said
deflectors L1, L2, L3, L4 are provided; which compel the wind to deviate from its
tangential course and thereby enable the powder to drop into the wagon at a normal
rate of speed, so that any impact of the particles of the powder upon each other,
and the ensuing, extremely injurious shocks and pressure, are effectually avoided.
Also, the fan like operation of the barrel affords the material advantage that the
noxious gases (such as hydrochloric acid gas or hydrofluoric acid gas for example),
escaping from the superphosphate, and any impurities in the form of dust, are
gathered up by suction and carried off into the atmosphere, whereby the operatives
in the room are saved from much inconvenience. If from any practical considera-
tions it should be desirable that the superphosphate should be disintegrated not
immediately after leaving the chambers, but only after having been collected and
left at rest for a time, the mechanism herein described may also be applied to the
stored material, as will be readily understood.
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:-
1. A process for disintegrating or comminuting sunamihannhatan.
17.

page_text: feature of which process is that the warm material as it is delivered from the
chambers wherein it is produced, while in the inspissated or coagulated condition,
is by suitable means cut into thin sheets or shavings, and thereby after cooling,
made to yield a dry, readily dispersing powder without the aid of any further
mechanical appliances, substantially as herein before set forth.
2. The construction and use of apparatus for the performance of the process
referred to in the 1st Claim; the main feature of which apparatus is that the
superphosphate is conveyed to cutters arranged after the manner of a grating
around the periphery of a barrel, which, as they rapidly revolve, cut or shave the
superphosphate into thin layers, which, through the co-operation of the wind or
blast, produced by the rapid rotation of the barrel,-crumble to a fine powder,
substantially as described and shown by the drawings.
3. The construction or arrangement of parts of the apparatus referred to in the
2nd Claim; whereby a speed of motion is imparted to the cutters in excess of that
at which the superphosphate is fed or descends, so as to prevent any of the material
dropping through the intermediate spaces between the cutters without being
divided thereby, substantially as set forth.
WM. BROOKES & SON.
55/56, Chancery Lane, London, Agents for the Applicant.