Note: Descriptions are shown in the official language in which they were submitted.
104586S
ACKGROUND OF THE INVENTION:
This invention relates to improvements in disc re-
finers providing for a simple, effective and controlled
venting of steam produced in a ~isc refining operation.
It is particularly advantageous in application to double
revolving disc refiners and it will be so described by way
of illustration. However, it is to be understood, and
should become obvious, that the application of the invention
is not so limited, and such is not intended.
The invention is directed to minimizing problems long
evidenced in use of the prior art disc refiners. It has
been found that substantially all the power applied in a
disc refiner is converted to heat, developed as material is
reduced between the relatively opposed refining surfaces
of the refiner discs. A major portion of this heat functions
to convert the moisture or liquid which is present to steam.
Another portion of this heat is absorbed by the material
being refined. The degree of heat developed is the source
of the problems to a solution of which the present invention
is directed. To understand the problem, consider if you will
that in the operation thereof a disc refiner will generate
heat capable of producing about a ton of steam at 212F.
per ton of wood or fibrous materials passed between the re-
finer discs when power is applied at the level of 60 H.P.
days per ton of the material delivered in chip form at 15%
consistency. Such a level of operation, or one with an
even higher "effective" power input, is desirable to en- -
able higher consistency refining and to obtain high quality
products or, in the alternative, to enable the obtaining
of the same quality products with a lesser power input.
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: 1045~65
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However, due to the considerable magnitude of steam de-
veloped, it has been found difficult if not impossible to
operate a disc refiner under such conditions for any period
of time without serious and undesirable consequences. As a
matter of fact, experience has sho~n that when utilizing
prior art disc refiner equipment one cannot afford normally
to put more than about 50 H.P. days per ton into any disc
refining operation and expect any degree of operating ef-
ficiency.
The nature of the operational problems solved by the
present invention is exemplified as follows.
With an overabundance of steam, while part of the steam
~ .
developed will exit with the refined material and in such
case merely represent a loss of energy, the steam remaining
in the disc refiner will, in conventional equipment, often
times create a blowback condition. The import of such a
condition is that the steam will move to interfere with the
inflow to the refiner of the material to be refined. Of
. .
particular concern in the production of fibrous pulp is the
fact that the interference of the steam will cause a non-
uniform rate of material infeed and consequently a non-
uniform quality of the end product issuing from the refiner.
In many instances it has been found that the quantity of
steam produced between the refining surfaces of a disc re-
finer in the course of its operation is so great that there
is not only an interference with infeed but in fact a de-
velopment of sufficient pressure in the eye of the refiner
to completely block incoming material from passage to and
between the refining surfaces of the refiner discs. This
last can occur even though a positive displacement infeed
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iO4S865
device is provided in the feed passage leading to the inlet
to the refiner. As a matter of fact, the restriction of
the infeed passage by the positive displacement feed device
can contribute to the buildup of the pressure created in the
eye of the refiner. In any case, the foregoing presents a
concise description of the problems in the prior art which
can be alleviated by usage of embodiments of the present
invention.
It has been the practice in the prior art to offset
some of the problems above enumerated by the introduction of
excess water with the material heing refined, the purpose
being to quench the steam. While this has helped to some
degree, it is not only wasteful but it does cause an un- -
desirable reduction in the consistency of the material be-
ing refined and a consequent reduction of the quality level
of the resultant end product.
SUMMARY OF THE INVENTION:
The primaxy objective and achievement of the present
invention is to reduce the normally encountered buildup of
excessive pressure in the "eye" of a refiner during a disc
refining operation.
To illustrate a means and method by which this objective
can be achieved, the present disclosure shows the invention
as embodied in a double revolving disc refiner which is
basically similar in construction to that of the refiner il-
lustrated in U.S. Patent No. 3,709,443. Such a refiner in-
cludes a pair of discs the refining surfaces of which are
positioned in directly opposed, adjacent and relatively
closely spaced relation, which discs are caused to rotate,
one relative the other, as material to be refined is passed ~-
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1045865
between their opposed refining surfaces. In accordance
with the present invention, the one disc constituting the
control end disc, in the example illustrated, is shown to
include a plurality of vent holes or passageways communi-
- cating at one end with an area of the space between the discs
known as the "eye" of the refiner, or adjacent thereto.
The outermost ends of the vent holes or passageways, which
are arranged to open from the backside of the control end
disc, are commonly communicated with conduit means the
nature and extent of which provides for steam received there-
in by way of said passageways to be directed to discharge
exteriorly of the refiner housing. The conduit means is so
coupled to the control end disc as to maintain its oper-
ative relation to the vent holes or passageways in the
event the control end disc may be moved to or from the
` opposite (feed end) disc to produce a required spacing be-
tween the disc refining surfaces.
Particular features to be noted in the illustrated em-
bodiment of the invention include the provision of vent
holes or passageways the axial length of each of which is
relatively short since it extends directly through the body
of the control end disc in an essentially straight line path,
from one face of the disc to the other. In connection with
a feed end disc such as illustrated, the exemplary embodi-
ment shows an arrangement wherein the feed passages in the
feed end disc and the vent holes or passageways in the
control end disc commonly communicate with the same general
area of the space between the discs, adjacent their centers.
By virtue of the particular nature and positioning of
the vent holes or passageways in the control end disc as
1045865
here provided and their continuing common communication
with the conduit means as indicated, excess steam produced
in the course of a disc refining procedure is continuously
and effectively channelled from between the discs and to
points exterior to the refiner housing. Means provided to
regulate this transfer of steam insure optimal control of
the environment within the refiner and in the area between
the disc refining surfaces. By virtue of this arrangement,
the invention has produced unobvious results in its appli-
cation.
One important benefit of the invention is that it en-
ables disc refiners to operate on slurries having a higher
consistency of solids and with an "effective" power input at
a much higher level, even up to 70 to 90 H.P. days/ton of
the material delivered, with proportional increase in the
quality of the end product. By the same token it obviates
the need for applying excess water to quench steam as would -
otherwise be required. The end result, in any case, is to
reduce the pressure developed in the eye of the refiner and
to enable the refiner to produce the same quality pulp at
lower H.P. days/ton than was previously possible. De-
rivative results include more uniform infeed of material to
be refined and an elimination of overload and stoppage
of a positive displacement feeder, if the same should be
employed. Where the refiner is to operate under pressur-
ized conditions, the invention may enable the elimination
of a cross screw such as is normally required to in-
sure positive delivery of material to the refiner. Of
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104S~365
course, inherent in the operation of a disc refiner
modified in accordance with the invention is the
conservation of energy.
I~hile the invention will be described as incorpor-
ated in a double revolving disc refiner, it should be
obvious therefrom that similar principles may be
employed to modify a single disc refiner to embody
the features of the present invention.
It is accordingly a primary object of the inven-
tion to provide improvements in disc refiners render-
ing them more efficient and satisfactory in use,
~- adaptable to a wider variety of applications and
unlikely to malfunction.
A further object of the invention is to provide
` improvements in disc refiners enabling them to oper- -
ate with delivered materials being maintained at a
higher consistency of solids.
- A further object of the invention is to provide
improvements in a disc refiner obviating the problems
normally produced by the production of steam in the
refining procedure.
Another object of the invention is to provide im-
provements in disc refiners enabling such refiners to
produce a quality end product at lower H.P. days/ton
than was previously possible.
- ~045865
An additional object of the invention is to
operate a disc refiner in a manner to conserve energy
and to produce higher ~uali~y end products by obviat-
ing the need for exce~ss water to quench steam in the
disc refining operation.
A further object of the invention is to provide
a disc refiner with improvements possessing the advan-
tageous features, the inherent meritorious character-
istics and the means and mode of use herein described.
With the above and other incidental objects in
view as will more fully appear in the specification,
the invention intended to be protected by Letters Pat-
ent consists of the features of construction, the
parts and combinations thereof, and the mode of oper-
ation as hereinafter described or illustrated in the
accompanying drawings, or their equivalents.
Referring to the accompanying drawing, wherein
one but not necessarily the only form of embodiment
of the invention is illustrated,
Fig. 1 is a generally diagrammatic illustration,
in cross section, of a double revolving disc refiner
embodying features of the present invention.
The refiner illustrated in the accompanying draw-
ings to exemplify an embodiment of the present
invention is a modified version of that illustrated ~
; in the previously mentioned U. S. Patent 3,709,443. ~ -
As may be seen, the refiner is a double revolving ~ -
disc refiner, both of the refiner discs being arranged ~
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1045865
to rotate, with each moving re:Lative the other.
As will be self-evident only 80 much of the ref-
iner detail is here illustrated or described as may
be neces~ary for an understanding of the present
invention. The nature and character of the parts not
shown or described in detail obviously may be seen
with re~erence to the aforementioned U. S. Letters
Patent, or they are conventional and will be well known
and understood by tho~e versed in the art.
The refiner shown in the arawings comprises a
pair of refiner discs 28 and 30 housed within and
free and clear of the interior surface of the refiner
case 10. The case 10 is comprised of a vertically
oriented tubular waist portion 16, capped to one end
by a dome-shaped top portion 12 and to the other
vertical extremity by a dome-shaped bottom portion
14 which is relatively inverted. As seen in the draw-
ing, in transverse section, the relatively remote wall
portions 18 and 20 of the waist portion 16, in an
axial sense, are orientea in generally vertical planes.
Also disc 28 i8 80 mounted that its back surface is in
immediately ad~acent, closely spaced relation to the ~;
interior surface of the wall portion 18 while its
operating surface is in a plane parallel to 3aid
wall portion.
The refiner di3c 28 has a central aperture accom-
modating one end of a drive ~haft 40 to which it is
fixed. The shaft 40 is directed outwardly of the case
_g_
104586S
10 through the center of an inlet aperture 17, pro-
vided in the wall portion 18 immediately to the rear
(or to the left as illu~trated) of the disc 28.
The interior wall surface of the wall portion 18
include~ a recessed shoulder 22 which rims the aper-
ture 17. The outer peripheral limit of the shoulder
22 is bounded by a shallow cylindrical wall surface
24. A ~imilar shallow cylindrical, axially directed,
wall surface 25, aligned with and in end spaced rel- :
ation to the wall surface 24, i8 defined by an annular
ring-like projection from the rear face of the disc 28.
Seated to the rear surface of the disc 28 and against
the wall surface 25 is the base portion of an axially
pro~ected ring element 46. The projected end of the
ring 46 provides an annular vertically oriented surface
disposing in an almost touching and parallel relation ~:
to the shoulder 22.
The configuration of the innermost peripheral sur-
face of the ring 46 i~ such that its pro~ected end por-
tion 27 has a cylindrical contour adapted to form adirect axial extension of the wall surface bounding the
aperture 17. Following the surface portion 27, in the
direction of the disc 28, the remainder of the inner
peripheral ~urface of the ring 46 i3 provided with a
conically expanding configuration. ~ :
The line defining th~ expanded extremlty of the
inner perlpheral surface of the ring 46 is in p~riph-
erally rimming relation to the entrance ends of a
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1045865plurality of infeed passage~ 29 formed in the body
of the di~c 28. The entrance ends of the passages
29 are arranged in a circularly spaced relation, in
concentric, ad;acent, radially spaced, relation to
the drive shaft 40. The pas~ages 29 are straight
line passages formed to extend to the operating
face of the disc 28 in a conically divergent pattern,
clearly ~een from their generally diagrammatic ~howing
in the drawing. The discharge ends of the passages 29
open from the operating face of the disc 28 at loc-
ations immediately ad~acent the inner peripheral limit
of a series of conventional, circularly arranged, ref-
iner plate~ fixed to provide the disc with its refining
surface.
The outer peripheral surface of the ring element
46 is formed with a circumferential groove nesting a
complementarily shaped male formed projection provided
on a r~ng-like element 26 fixed in connection with the
wall surface 24 bounding the shoulder 22. By virtue
of it~ clo~ely spaced relation to the ad~acent sur-
face of the shoulder 22 and the ring element 26, the
ring element 46 provides, on rotation thereof with
the disc 28, a seal. This seal prevents material fed
through the inlet aperture 17 from bypassing the disc
28 in a manner believed obvious and well known in the
art.
A tubular wall ~tructure forming a feed spout 32
defines a material feed pa~age 34 directed downwardly
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104586S
to the inlet aperture 17, in a verti~ally inclined
path. The lowermo~t end of the wall structure forming
the feed spout 32 embodies an external flange which is
abutted with and welded to a reces~ed shoulder formed
: in the outer surface of the wall portion 18 of the
ca~e 10, in immediately rimming relation to the aperture -
17.
In the vertical plane of it~ discharge end, the
diameter of the feed passage 34 i8 slightly less than
that of the inlet aperture 17. By reason of the noted
difference in dimension and the centered alignment of
the lower end opening of the feed passage 34 with
respect to the upper portion of the inlet aperture ~::
17, the flanged lower end portion of the wall ~truc-
ture of the feed spout will overlap the lowermost
portion of the inlet aperture 17. This arrangement
is provided to enable material directed through the
inlet aperture to more expeditiously flow to and
; through the infeed passages 29 in the disc 28.
As the drive shaft 40 extends outwardly of the
: case 10 through the center of the aperture 17 it i~
fir~t directed through the lower end portion of the
feed passage 34 and then through a packing gland and
follower assembly 42 defining a seal thereabout as
it pro~ects through an opening in the wall portion
of the feed spout 32 located in an ad~acent vertic-
ally spaced relation to it~ lowermost end portion.
Within the case 10, the refiner plates in
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lV45865
connection with the outer peripheral area of the disc
28 are in immediately opposed, clo~ely adjacent, rel-
ation to ~imilar refining plate~ fixed to the adjacent
operating ~urface of the disc 30. In accordance with
the present invention, the embodiment thereof in the
di~c 30 here illustrated proviaes that the di~c ha~
a plurality of straight line passageways defining
vent hole~ which open at one end from the body of the
di~c 30, from an annular portion of its operating
face, to the space between it and that of the disc
28, at location~ immediately inward of the inner radial
limit of the di~c refining plates. This annular portion
of the operating fa¢e of the disc 30 i~, in the example
illu~trated, in direct and axial alignment with an
annular surface portion of the operating face of the
disc 28 occupied by the circularly ~paced discharge
ends of the infeed passages 29. As shown in cros~
.....
section in the drawing, the vent holes 31 extend from
the operating face of the disc 30 to its rear or
opposite face in a conic~lly convergent pattern.
This provides that the vent hole~ open from the oppo~-
ite face of the disc 30 in concentric, ad~acent, and
: closely spaced relation to an aperture at the disc
center accommodating one end of a drive shaft 48 to
which the di~c i8 suitably fixed.
; In the mounting of the refiner disc 30 the drive
shaft 48 i8 placed in direct coaxial alignment and
in end sp~ced relation to the shaft 40, as may be :
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~ 045865
seen from the accompanying drawing. The shaft 48 is
thus arranged to extend outwardly from the case 10
and through the center of an appropriate aperture
provided in the wall surface portion 20. This aper-
ture in the wall surface portion 20 is partially
capped by an annular cup-shaped plate segment 53
including an external flange at the mouth thereof
by means of which the plate ~egment is seated to and
connected with the wall portion 20, as may be clearly
seen with reference to the accompanying drawing. Suit-
able ring-shaped bearing means provided to line the
inner periphery of the plate segment 53 accommodates,
in bear$ng relation thereto and for axial ad~u~tment
therein, one end of a tubular cartridge 52. The
: cartridge 52 embodies therein, in a conventional manner,
a packing gland and follower assembly 50 accommodating
the pro~ection therethrough of the shaft 48 as it ex-
tends in a sense outwardly of the case 10. As may be
seen, the external diameter of the aartridge 52 i8 en-
larged outwardly of the plate segment 53 where the
cartridge is abutted to a shoulder prov~ded by an en-
largement of the drive shaft 48. Bearings (not shown)
: provide for the rotation of the shaft 48 within the
cartridge 52 and the cartridge i~ suitably fixed to
the ~haft for movem*nt therewith. Thus the cartridge
.; 52 ~8 contained for movement with the disc 30 and the
shaft 48 in the event the lattèr are axially adju3ted to
achieve a de~ired spacing between the refiner plates
positioned in ad~acent closely ~paced relation by their
connaction with and mount on the di~cs 28 and 30.
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1045B65
The adju~ting mechanism may be of any suitable char-
acter well known to those versed in the art. Since
it form~ no part of the present invention, it is
neither shown nor further described.
Attention is directed to the fact that the drawing
illustrates bearing hou~ings 44 and 54 re~pectively for
the shaft 40 and the shaft 48 and cartridge 52. Such bear-
ing housing~ will be provided on the conventional refiner
base to which the refiner illu~trated will be convention-
ally mounted together with the drive motors for the ~hafts
-~ 40 and 48. Again, since such details are une~sential to
an understanding of the present invention, they a~ well as
the other details of similar character are neither shown
nor part~cularly described. S-~ch details as this, and
detail~ of a mechanism for axially adjusting shaft 48, are
exemplified in the aforementioned U.S. Patent 3,709,443.
Referring further to details contributing to the
embodiment of the present invention, attention i~ dir-
ected to the fact that the openings of the vent holes
or pa~ageways 31 from the rearmost face of the disc
30 are arranged in a closely and circularly spaced
annular arrangement, concentric to and immediately
about the hub portion of the disc 30 through which
extends the shaft 48. The outer peripheries of the
rearmost openings are immed$ately rimmed by a recessed
shoulder 41 ~ormed in the ro~rmost face of the disc
30. The shoulder 41 provides a ~eat for a ~uitably
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1~145865
fixed ring 58 which i5 axially projected in the dir-
ection of the wall surface portion 20 of the case 10.
The projected extremity of the ring 58 is tele~coped
about and accommodates therein one end of a co-axial
tubular sleeve structure 56 the opposite end of which
i8 suitably fixed by a sealed engagement thereof with
the innermo~t face of the closure plate ~egment 53.
The relation of the inner surface of the ring 58 to the
outer surface of the sleeve 56 is such that on a rotation
of the disc 30 a continuing seal i~ provided there-
between. The seal is of a nature to accommodate an
axial movement of the shaft 48, to provide for such fine
ad~ustment of the spacing between the surfaces of the
relatively opposed refining plates on the discs 28 and
30 as may be de~ired.
~The sleeve structure 56 iB provided with an opening
;57 in which i8 fixed one end of an elliptical configured
tubular duct segment 59 defining one end portion of a
duct ~tructure 33. The latter provides a continuing pas-
sage one end of which opens to the interior of the sleeve
56 as des¢ribed and the opposite end of which i8 located
exterior to the case 10. In the case of the example
; illu~trated, a ~egment 61 of ~he duct structure 33 which
immediately follows the segment 59 i~ formed to provide
a generally conical expansion of the duct passage to
achieve an enlarged cro~s section thereof which i~ gener-
ally uniformly continued in following segments of the duct
structure as it is extende~ through an aperture provided ~-
in the top of the case 10, at which point a seal is
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1045865
provided between the case 10 and the duct structure 33.
For purposes of illu~tration the duct structure i~ merely
shown to extend to some point exterior to the case 10.
The duct structure may be interconnected to a heat recov-
ery system or any other apparatus provided in a refining
in~tallation, to deliver steam thereto as and when
required. Incorporated in the duct structure 33 i~ a
suitable valve 35 which may be ~electively adjusted to
determine the amount of ~team that may be permitted to
pa~s from the case 10 by way of the duct 33. While
the opening 57 is shown to be po~itioned at the top portion
of the sleeve 56, this is merely for convenience of illu5-
tration. It will be obvious to those versed in the art
that the opening 57 may be otherwise located.
In the case illu~trated the feed spout 32 and a
~` tubular extension 38 thereof, by mean~ of which the
feed spout connects to a supply of material to be ref-
ined, incorporates in its feed passage a screw type ;`
po~itive displacement feeder device 36. While this
device iB illustrated, under certain conaitions and
applications such as in the use of the disc refiner
as a pres~urized refiner the feeder 36 may in accord-
ance with the invention be eliminated.
The aforementioned embodiment particularly des-
cribed and diagrammatic~lly and schematically illu3-
trated will function in a refining procedure, as
follows.
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104S865
In the operation of the cli~c refiner illustrated
the invention improvements function very simply and
very effectively. As the material to be refined 18
directed inwardly of the feed ~pout 32 utilizing the
screw fee~er 36 and operating the refiner a~ a free
discharge refiner, the material delivered by the ~crew
will drop from the lower end thereof into the relatively
clear discharge end portion of the passage 34. Under
the influence of the material further delivered, this
material to be refined will be cau~ed to move smoothly
and freely to and through the inlet aperture 17 and,
by way of the ring 46, into and through the flow pas- -
sages 29 of the rotating di~c 28. From the flow pas-
sage~ 29, the material to be refined will enter the
space between the operating face~ of the relatively
rotating discs 28 and 30 immediately inward of the
refining throat at the entrance ends of the relatively
opposed refining ~urfaces provided on the di~c~. Due
to the inclination of the flow pa~sages 29, the material
to be refined will tend to move, immediately, bet- ;
ween the refining surfaces and radially outwardly
thereof, in the process of which to h~ve their fibers
separated, one from the other. As i~ well known, in ; -
view of the slurry form of the material as generally
delivered in a pulp refining operation, steam will be
developed a~ the power applied in the disc refining
procedure i8 converted to heat by reason of the refin~
ing operation. In accordance with the present invention,
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1045865
rather than exce~ steam building up between the discs
and in the eye of the refiner, the vent holes provided
by the passageways 31 wlll provide paths for portion~
of the ~team to pa88 directly through the body of the
disc 30 and into the sleeve 56, to exit by way of the
duct 33. The steam may be permitted to exit either
freely or to a degree permitted by the setting of the
valve 35, the latter being ad~ustable to provide a
controlled passage for steam to move from the duct
- 10 33 to a place of u~e. It will be cbvious, of course,
that this steAm, which i8 so quickly and easily vented,
can be channelled by suitable plumbing into a pre-
steamer or digester ahead of the refiner. Thi~ will
most effectively reduce or eliminate the requirement
for fre~h steam that would normally be required and
applied in ~ refiner installation absent the u~e of
the improvement~ of the present invention. Another
benefit of the venting of steam as here provided i8 that
the reduction in presQure re~ults in less ~team being
di~charged with the refined material. Consequently
there i~ a significant ~avings in energy which can be
utilized elsewhere.
Attention i8 dirscted to the fact that due to the
centrifugal force developed in the refining procedure,
any particles which might tend to move from between the
di~c operating ~urfaces and into the pa~ageway~ or
vent holes 31 would be drawn therefrom under the
influence of the centrifugal force and inducsd to move
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1~)45865
radially outward between the rlefining plate~ on the
counter-rotating operating surface~ of the discs28
and 30.
A feature of significance in the particular embod-
iment illustrated i~ that manufacturing costs can be
saved by the arrangement of the pas~ageway~ 31 in the
disc 30 to be e~sentially the same as the arrangement
of the infeed passages 29 in the disc 28. One can then
use ~he ~ame disc as both an infeed disc such as the
disc 28 and a control end disc ~uch a~ the disc 30.
Of cour~e, while thi~ is desirable, this arrangement
i8 not required to utilize the benefits of the inven-
tion.
Under the circum~tances, by rea~on of the very
~imple venting arrangement, whereby there is a natural
venting from the eye of the refiner or ad~acent thereto,
blowback condition~ are virtually eliminated. This
means that with a free discharge refiner one can have
a uniform rate of feed, determined by the operation of ;
the feeder ~crew 36. The flow of material will in any
case be smoothly directed to the throat of the refiner
and move radially outward therefrom under the influence
of centrifugal force. In its radial outward movement the
material will be refined ln accordance with the reduction
set into the refiner by vlrtue of the nature of
the refining ~urfaces of the refiner plates and
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1045865
their spacing. The inflowing material can be readily
controlled to permit the ~team developed in the refin-
ing procedure to be directed Inwardly toward~ the eye
of the re~iner and quickly vented to the degree desired, to
be directed clear of the refiner case by way of the
duct 33. The regulation of the steam permitted to
exit will be such to insure the required conditioning
of the material during the refiner operation.
In the instance illu~trated there i~ a 3howing,
of a generally d$agrammatic nature, evidencing an
outlet 37 from the ca~e 10 through which the refined
materi~l ~ssuing from the outer periphery of the refiner
disc~ a~ they counter-rotate may drop in a free di~charge.
Of cour3e the nature and placement of the discharge
opening will depend on the application of the reflner.
As noted previously, in certain instance~ where
the refiner is operated as a pressurized refiner,
being appropriately sealed in the well known manner,
the ability to con~rol the steam pressure as provided
by the lnvention may eliminate the need for the conven- -~
tional ¢ross screw fee~er which i8 normally employed
- in delivering material to a preRsurized refiner.
To summarize the benefits of the invention, ~ince
the invention eliminates the need for excess water to
quench ~te~m that is normally produced in a di~c ref-
iner, one can operate the refiner very effect$vely on
materials delivered which have a higher consi~tency
of ~olids than previously contemplated. A consequence
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: 1045865
of the inventlon in the alternative is that on the one hand
one can apply a greater power input to a disc refiner than
W~8 previously pos6ible without the usual operational
difficulties and with corre~pondingly increasing quality
of the end products wh~le on the other hand one can more
effectively utilize a lower power input to achleve a higher
quality end product than was previou~ly pos~ible.
An obvious additional accomplishment of the invention
i8 that it enables a more uniform and controlled feed of
the material to be refined and consequently it insures a
higher quallty end product. In the process there is a
conservation of energy. Obviously, moreover, the invention
eliminates overload and stoppage conditions which would
normally interfere with a proper infeed of material to be
refined.
Much care has been taken to avoid introduction or show-
ing of those details of a refiner installation which are not
material to an underst~nding of the invention and under such
circumstance~, it i~ believed that the invention, it~ ob-
~ectives and it~ achievements should be quite clear fromthe foregoing de~cription of an exemplary embodimen~.
From the above description it will be apparent that
there i5 thus provided a device of the character described
po~sessing th particular features of advantage before
enumerated as desirable, but which obviously is susceptible
of modification in its form, proportions, detail construc-
tion and arrangement of parts without departing from the
principle involved or sacrificlng any of its advantage3.
While in order to comply with the statute the inven- -
tion has been described in language more or less specific
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1045865
a~ to ~tructural feature~, it i8 to be understood that
the invention is not limited to the ~pecific featurQs
shown, but that the mean~ and construction herein dis-
closed comprise but one of several modes of putting
the invention into effect and the invention is there-
fore claimed in any of its forms or modifications
within the legitimate and valid scope of the appended
claims.
.
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