Note: Descriptions are shown in the official language in which they were submitted.
The invention relates to a method for the hydraulic
conveyance of solids, pxeferably coal, in a transport
medium in the case of wnich the raw material to be con-
veyed is classified before being placed in the hydraulic
conveying plant in~o several fractions, and to an a~paratus
~or carrying out the method.
The hydromechanical mining of coal and the transport
of the raw coal to be conveyed over extensive distances
both horizontally and also vertically has been accepted
practice for a number of years. In this respect diffi-
culties arise because the raw coal to be conveyed can
only be transported hydraulically up to a certain grain
size. In order to avoid excessively high pressures the
practice was taken even in the early days of classifying
the raw coal to be conveyed while still underground so as ~o
produce a transportable grain fraction and a non-trans-
portable grain fraction. While the fine grain fraction
can be transported over long distances even in the ver-
tical direction, ~he coarse grain material is separated
and in the previously conventional mannex is hauled in
wagons to above ground or made use of in some oth~r
manner under~round or comminuted. Furthermore it has b~en
found that in the case of the hydraulic conveyance of `~
solids with different grain sizes and different densities ~:
the different resistances of tne solid particles in the
flowing liquid glve rise to substantial di~ferences in
speed of the so:lid particles. This is disadvantayeous as
regards the hydraulic conveyance in as far as the different
transport speeds in the shaft duct lead to undesired con-
centrations of materials and cloyging~ Furthermore it hasbeen found that for such a heterogeneous mixture a nigher
..;,
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transport speed i5 necessary. ~ince com~licated classifi-
cation and sorting underground gives rise to excessive
costs the disadvantages tied to the above me~tioned effect
have so far been put up with. Attempts have only been made
to avoid tne effect by dividing out, as already mentioned,
the coarse grain siæes and transporting tnem separately in
a transport wagon.
In view of the fact that it is more particularly the
coarse fractions or grain sizes of the heavier components
of the raw conveyed coal that lead to the trouble with
clogging one aim of the invention is that of providing a
method which makes pGssible an increase in the volume con-
c~ntration at a lower conveyance speed and simultaneously
avoids concentrations of material and clogging. At the
same time an apparatus is to be created with which the
method in accordance with the invention can be put into
practice.
In order to a~tain these and other aims the invention
provides that the raw material for conveyance is only
fractionally subjected to sorting with respect to the grain
fractions which predominantly lead to clogging after classi- -~
fication and before hydraulic conveying. The method in
accordance with the invention is accordingly intended to
hold back all parts of the raw material for conveyance,
whose settling velocity is greater than the settling velo-
city of the maximum sized pure material to be conveyed.This appli~s for a raw coal to ~e conveyed for e~ample,
hile in the case of an ore conveyance must be precisely
~ the reverse. Tne separation of heavy matter witll a size a'Dove
10 mm furthermore offers the advantage that in the treatment
of the material above ground the material with a grain size
above 10 mm only comprises pure coal and
~9~
all material above 10 mm can be further processed in the
fine grain processing system without changing the washing
system. ~he heavy fractions separated underground can
therefore be hauled out of the mine outside normal con-
veying time and, as a further possibility, however, can
~e used as pac~ing.
The desired sorting effect is achieved in a particu-
larly accurate and satisfactory manner if, in accordance
with the proposal of the invention, the classified material
~ is subdivided intodefined quantities and is premi~ed with
the separating medium before it is abruptly, that is
to say speedily charged into a shaft filled with separating
medium. In the case of sorting the invention takes ad-
vantage of the physically occasioned difference in the
settling rate of fractions of materials of the same si~e
~ut which have a considerable difference in density. Thiseffect is particularly well brought into play when the
material to be charged has been classfied as strictly as
possible beforehand. The individual fractions are
then subdivided by suita~le means into portions of the
same size and then even at this stage premixed with the
separating medium in order, even at the ~eginning of the
separatiny operation to have tile same starting state for
the individual grains and in order to avoid movemen~s of
the separating medium which would impede the separating
operation. The material whicll was classified into the
individual fractions in the individually defined quantities
is then removed underwater in the appropriate shafts, such
removal heing carried out suddenly, that is to say at high
speed in order to ensure that approximately all grains sink
downwards simultaneously in the separating medium and
t-hat the desired separation from the ~ixture does in fact
occur here.
In accordance with the invention separate shafts are
provided for the individual fractions and they have a length
S corresponding to the grain size. The shortest shaft is
provided for ~he smallsst parts and the longest shaft is
provided for the largest parts. This makes it possible to
ensure that the residence times of tne individual materials
to be separated in the shats placed alongside each other
are of equal duration.
The method in accordance with the invention can be
carried out with a separating device, which consists of
allotting means, a housing filled with water and removal
means and in the case of which, in accordance with the
present invention, a drive shaft is provided with several
allotting means, which are arranged with an offset in
relation to each other on the drive shaft and in the case
of which the drive shaft is provided with means for pro-
ducing a desired timing relationship between it and the
~0 cylinders. Ilith such a separating device it is possible
to obtain simultaneously all fractions which occur within
classi~ication, and they can be sorted in the device and
automatically se~arated from each other. The use of the
drive shaft and the cylinders, which serve for actuatins
the slide and the flaps, as timing means makes possible
a simple and mutually timed control of the allotting means
and the separating means.
The number of grain fractions produced as part of the
classification is determined in accordance with the type
: 30 of the material supplied. Generally tile material supplied
will have to be classified into seven to eight grain sizes,
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1366
one grain fra~tion ~eing tne tailinys, ~ilich yen~rally
cannot be nydraulically transported without special trea~-
m~nt. AccQrdingly in accordance with the invention a num-
ber of allotting devices is provided which corresponds to
the number o~ desired grain fractions . . Generally a sepa-
rating device in accordance with the invention will accord-
inyly have six or seven allotting devices, which are of the
same basic structure. This has the purpose and simultane-
ously offers the ~dvantage of making it possibla to sort
immediately and simultaneously the whole of the raw ~
material to be conveyed in all grain sizes, with the ex- ~ ~r
ception o~ the tàilings.
The allotting device is the intermediate member be-
tween classification and separating shafts. It can in ~;
accorda~ce with the invention store material coming fromthe sieve. In this respect it is possible, in accordance
with the invention , for the allotting device to have
several, preferably four chambers, which have the same size
of opening and the same filling volume. The identical con-
struction of the chambers of the allotting device is neces-
sary, since timing can only be caused to function satisfact-
orily if the quantities passed into the separating shaft,
respectively have the same grain size and the same volume.
Furthermore they should as far as possible all be passed
simultaneously into the separating medium, which fills the
sha~t.
In order to avo~d early emptying of t~e chambers in
the case of the separating device of the invention the
chambers of tne allotting device are surrounded by a cas-
ing, which closes simultaneously at least the opening ofof two cham~ers. Accordingly it is possible to fill a
36~
cnamber simultane~usly with the new material, while the
second chamber, which has become filled at the same point
in time in part with water already, can be emptiea by
sudd~n or high speed opening of the slide.
Production of movement in the water- surface and in
the water column can under some conditions lead to impair-
ment of the separating result. For this reason the
material is to be mixed with the separating medium even
before it is fed into the separating shaft. Such a mixing
operation of the material with the separatiny medium is
achieved in accordance with the invention ~y ensuring that
the allotting device ex~ends partly into the housing filled
~7ith the separating medium. In this manner the separating
medium can pass through slots or other openings, which a~e
provided in the casing or the slide, into the respective
lower chamber and wet the material located in it. Satis-
factory sorting in accordance with the individual grain
fractions is ensured in accordance with the invention if,
as proposed, in the intexior of the housing a number,
corresponding to the r.umber of the allotting devices of
shafts is provided. This makes it possible to ensure that
each individual grain fraction can be separated up, without
any influence due to external factors, in accordance with
the density.
Turbulence in the sllafts filled with the separating
medi~n is avoided in accordance wtih the invention by giv-
ing the shafts a square cross-section.
The separation of tlle components, passed at different
points in time ~o the lower end of the shafts, of the in-
dividual components is made simple in accordance wi~ll the
invention if, as proposed, at the lower end or the shafts
pivotall~ mounted grates are provided ~nd on the housing
a counter-member is provided which is pivoted. The two
pivotally mounted grates and the respective counter member
which is pivotally mounted then perform respectively
opposite movements so that firstly the neavier parts and
then after changing over the pivotally mounted grates and
the counter-member the lighter fractions can b2 passed in-
to the preceding compartm2nts at the lower end of the
housing.
A synchronous switching over of the pivotally mounted
grates and the counter-member is ensured, in accordan~e
with the invention, by associating one and the same cy-
linder with a l~ver syst~m with the pivotally mounted
grates and the counter-member. Owing to this simple engi-
neering construction~it is possible to ensure that the
pivotally mounted grates and the counter-member respectively
perform the necessary opposite movelnent.
The mov~men~s, in~luencing the d gree of success of
séparation, of the water column are avoided to a very sub-
stantial extent since the pivoting grates and also thecounter-member have openings on the surac~s. As a result
the resistance, which the medium has to meet on the move-
ment of the pivoting counter-members is kept as small as
possible. Since the pivoting members are at an angle to the
vertical in every position the sorted material can, without
falling through, move over the openings into the pivoting
counter-members.
The material provided sorted up into heavy and lighter
fractions is firstly deposit~d on the bottom of the housing
and from this position supplied to the coal collecti~g space.
For transport use is made, in accordanc2 with the
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6~
invention, of at least two conveyiny screws arranged in t~e
bottom of the housing. The use of conveying screws mak~s
it possible to feed in the material, whicA is then supplied
to the hydraulic conveying system, in a cor,dition which is
alxeady mixed to an extremely far reaching extent as r~gards
grain size. For tne heavier and respectively less valuable
components it is in this raspect also possible to use a
different transport device, since in this respect mixing is
no long r absolu~ely necessaxy.
The grain size distribution changes in accordance with
the hardness of the cQal mined. It can therefore be appro-
priate to change the grain rang~s of the fractions suitably
and/or to reduc~ or increase the number of fractions. Accord-
ingly there is the proposal in accordance with the invention
to adapt the number and l~ngth of the shafts to accommodate
these variations.
The cylinders, which actuate on the one hand the slide ;~
and on the o~her hand the pivoting grates and respectively
the pivoting counter-member are connected constructionally
with the drive shaft. In accordance with the invention
cams arranged to slide on the drive shaft are used as con-
trol members for tlle cylinders~ As a result the advanta-
geous robust construction is adhered to for the underground
arrangement. Furthermore on changes being made in tl-e com~
position of the material supplied or other operational con-
ditions the necessary times can be changed without any ex-
tensive difficulties by changing the cam discs and the seat
of the individual allotting devices.
It is particularly advantageous that o~ing to the cutt-
ing out of the dense fraction above 10 mm concentrations of
~9~
material an~ accoraingly clogging is prevented. In all the ~ -
hîgher volumetric concentration aimed at is achieved, ~Yhich
can be conveyed with a lower conveying speed. Fur~hermore
the separating device is generally sturdy and simple in
structure and accordin~ly it is adapted to the special con-
ditions in mining underground. T1e separating device can
be erected and operat~d in the vicinity of dead-end sha-fts
or shafts near the surface or in any other spaces suitable
for such purposes without any extensive investments. Such
successful op~ration was therefore certainly not to have
been expected by those skilled in the art.
The manner of operation of the s~parating device and
o,her features of the present invention will be described
in detail ~Jith reference to the following figures of the
accompanying drawings.
Figure 1 shows a section through the separating device~
Figure 2 shows a simplified side view.
Figure 3 shows a diagrammatic sketch of th_ timing or
control unit.
Figure 4 shows a timing diagr~n.
The separating device now to be described is intended
for separating coal and heavy fractions.
In Figure 1 a housing 1 encloses the main part, com-
pletely filled with water, of tne separating device. In the
interior 1 there is the shaft 2, shown in secti~n, which in
accordance with one form of the invention is preferably of
square cross-section.
A~ove ~he housing 1 there is tle supply trough conveyer
13, via which ~le raw material to be conveyed, subdivided
after classification into the individual fractions, is
_ g _
~L~9~86G
supplied to the individual allotting devices 3. The inner
part 33 rotating a~out the drive shaft 4, of ths allotting
device 3 comprises four evenly arranged and identically
constructed chambers 6, 7, 8 and 9, which move below the
inlet hopper 10 towards the slide 11. ~e drive shaft 4
is connected with the slide 11 for timed movement and the
cylinder 12 serves for opening and closing the slide 11.
The bottom 26 of the housing 1 is subdivided into two
component spaces, in which the two conveying screws 27
and 28 are to be found. The setting of the housing 1 at
an angle 29 ensures that th~ material conveyed is reliabl~
passed into the vicinity of the conveying screws 27 and
28 respectively. Above these parts, ~lat is to say on the
center wall 30 of the housing the pivoting counter-me~ber
24 is a~tached. Furthermore at the lo~er end 22 of the
shaft 2 on the shaft wall 31 the pivoting grates 23 are
fixed so as to allow movement. T~e inner part 33 and the
openings 21 of ~le chambers are surrounded by the casing
5 of the allottin~ device 3.
Tlle manner of operatiDn o the separating device is
as follows. The classified raw material to be coIIveyed
with a predetermined grain size range arrives via the
trough conveyer 13 in the chamber 6 just due to be filled
with it. Owing to the slow rotation of the rotor this
operation las~s a certain period of time so that the cham-
ber 6 can be filled with the material to be conveyed~ On
further rota~ion the chamber 6 will then reach the position
at ~hich in ~igure 1 the chamber 8 is located, which on
bein~ turned so as to~move beneath the level 34 of the
water, has already partly filled with water. The operation
of the cylinder 12 is controlled by the drive shaft 4 so
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~9~1~6~
tha~ it operates to move the slide 11 to an open position
at a predtermined instant so that the contents of the
chamber 8 and 6 respectively can be ernptied suddenly into
tne shaft 2 which is filled with water. In this shaft 2
there is, owing to the different settling rates of the
heterogeneous material the desired separating or sorting
operation. The particles ~hicn has the highest specific
gravity are the first to reach tlle lower end 22 of the
sha~t ~ and in accordance witn the position, represented
lQ in figure 1, of the pivoting grate 23 and the pivoted
coun~er-member 24, are passed into the space around the
screw 27, which in the exampla shown is used for the heavy
fraction. The specifically light material, that is to
say th~ coal, reaches the vicinity of the lower end 22 of
the shaft 2 only later. Then the pivoting grates 23 ar~
pivoted in the direction of arrow into the position shown
in dots, while the pivoting counter-member 24 performs a
mo~ement in tne`opposite direc~ionO This feature ensures
tnat the material to be conveyed ~coal) now arriving is
passed to the conveying screw 28, which is used for coal.
The actuation of the pivoting grates 23 and of the pivot-
ing count~r-mer,~er 24 is insured by the cylind~r 25 which,
as remains to be explained, is operated or tim~d via the
drive shaft. The cylinder ~5 is associated with a lever
system 32 which makes it possible to operate simultaneously
the pivoting grates 23 and the pivoting counter-member 24
in a mutually opposite direction. The pivoting grates and
respectively the pivoting counter-member have holes or
similar openings 50 that tne pivoting mer.~rs 23 and 24
offer the least possible resistance to the water. Tnis
particular feature of the pivoting members 23 and 24 is
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6~;
no~ repr~sented in the drawing.
Figure Z shows the separating device as a w~ole in
a simplified elevation view, in which the three-dimensional
arrangement of the individual shafts 2 with their dif-
ferent lengths and the pivoting grates 23, located res-
pectively at the lower end 22 of the shaft 2, and of the
pivoting counter-m~mber 24 will be seen togetner with fur-
ther specific eatures. Above the allotting device 3,
which consists of sevexal segmen~s arranged on the drive
sihaft 4 the supply conveyer troughs 13 are arrang~d via
which tne material to be conveyed, classified as inte~ded,
is fed. I~ the example shown in all six fractions are
supplied via the conveyer troughs 13 to t'ne separating
d~vice, which accordingly consists of six or respectively
five allotting devices. Tests have shown that it is
sufficient to divide the material which has a grain size
above lO mm into ~he following fractions: 10-20, 20-30,
40-50 and 50-60 mm. The material above 60 mm in grain
size is passed over the classifying device and if required
further processed and then fed into the classifying device
again. The correspondingly sorted material is,after sorting
w~th the help of the conveying screw 27 and respectively,
the collveying screw 28 following it, conveyed off and
placed in the coal storage container.
At ~le end of the drive shaft 4 there are the control
slides 14 associated with the individual removing segments,
that is to say the slide ll, the pivoting grates 23 and
the pivoting counter-member 24. As components for timing
it i5 possi~le to use conventional ~lements, Furthermore
t'ne arrangement in fisure 2 does not show the segments,
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g36~i
associated ~ith the individual shafts 2, of the allotting
device 3, which are indicated in figure l and denoted with
~e~erence numerals 6-9. The parts, mounted on the shared
drive shaft 4, of the allotting device are arranged res-
pectively witll an offset of 18 so that the removal of tilesolids for each individual allotting device occurs at dif-
ferent successiv2 points in time. Figure 3 shows the
principle of control with reference to part timing systems.
In the top of f-i3ure 3 of th~ timing unit 14 the three
cams 1~, 17 and 19 which belong together and are mounted
adjacent to each o~her on t~e drive shaft 4, a~e shown,
~hicll are responsible for actuating the two cylinders 12
ans 25. The four projections 16 of the cam 15 actuate
during a full revolution ~he cylinder 1~ four times for
a duration corresponding to the angle alpha. The pro
jections 18 of the cam 17 and the projections 20 of the
cam 19 control the cylinder 25 in such a ~anner tllat after
a time, whicll on the cam 17 corresponds to the angle
delta, the cylinder 25 is switched over and after a time
which on th2 cam 19 corresponds to the angle Psi, is
moved back into the initial position again. The time for
the timing or control operation itselE is the same for
the two cams and corresponds to the angle beta.
The bottom of figure 3 shows the same operations for
the next cams 15, 17 and 19, which are provided for the
cylinders 1~ and 25 of the next allotting device 3 and
respectivel,v the next shaft 2. All cams have the same shape
as shown in the top part of figure 3. They are only off-
set by t~ angle Delta on the common ~rive snaft 4. This
angular offset is also provided between the following
control or timin~ units 14 of the remaining parts of the
separating device.
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366
~ igure A SilOWS a control or timing ~iagram, ~hicn in-
dicates ~e timing of the system indicated in figure 3.
This timiny diagram will serve to show that the tim-
ing operations for the cylinders 12 and 25 and accordingly
the movements of the pivoting grates 23 and respectively
of the pivoting counter-member 24, which in fact all occur
underwaler, are listributed over the whole period of a
complete revolution of ~le allottiny device 3 so tilat only
a slight disturbance can be imparted to the comparatively
10 large quantit~ of water in the main part of the separating ~ !
d~vice. This disturbance is furthermore limited since the
shape of the shaft 2 is square in cross-section.
In accordance with the ernbodi~ent shown tne raw coal
to be conveyed is first classified for a ~rainsize of
below G0 r~m. The material larger than 60 rnm in size is
drawn off via the device shown. Its further tr~atTnent
does not forrll part of th~ subject matter o the present
invention.
The material below 60 mm in size is divided up as
follows -amongst the individual supply conveyer trougns.
13 All rnaterial below 10 mm including
the entrained water
13' Grain size 10-20 mm
13'' Grain size 20-30 mm
; 13' " Grain size 30-40 mTn
13'''' Grain size 40-50 mm
13''''' Grain size 5C-60 mm
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