Note: Descriptions are shown in the official language in which they were submitted.
10783Sl
`,
The invention is broadly concerned with the recovery
(in the sense of salvage) of waste paper as hereinafter
described by method and means conducing to superior economic
advantage over prior practices.
The salvage of waste paper currently appears to be
increasing in commercial importance. That is to say, paper
salvage objectives now seem to go beyond what might be termed
"basic" salvage in which the recovered product was commercial-
ly acceptable only for inferior uses such as roofing felt, for
example; the current trend being to try to upgrade the
recovered product to permit, when and if possible, more
economically advantageous uses thereof.
It will be appreciated that waste paper is often
presented or available for salvage in mixtures which may ;
contain components ranging from (superior) chemical kraft
papers to (inferior) newsprint; all being intermingled
together in random, heterogeneous, agglomeration. Accordingly,
to upgrade the paper recovered from such mixtures and to
improve the yield in a qualitative sense, it is preliminarily
necessary to sort the mixtures into their respective components
for processing separately from each other.
Waste paper mixtures as herein visualized are
obtainable from a variety of sources; such sources being of
no relevance to this invention so long as the paper provided
2~ thereby is dry with a moisture content not appreciably
exceeding 6 ~ and is capable of being milled in the manner
hereinafter described.
One such source might be the waste paper which is
scrapped daily in business offices and collected nightly by
the office cleaning staffs. Obviously, such waste paper may
B-9602 P/2 CA - 1 - ~
- ~ . .
1078351
well contain two or more components of various qualities
ranging from first quality stationery to low grade newsprint;
the whole thoroughly and indiscriminately intermingled
together to form a mixture as herein contemplated; this being
generally the form in which waste paper mixtures are obtained
from other sources.
It will be apparent that if a mixture is recycled
in the described form, the product recovered from the
recycling operation cannot be graded above its basest component
notwithstanding that it might contain elements of much finer
papers. Thus the principal uses made of the recovered
product have had to be confined to the base categories.
A broad object of the invention is, therefore, to
provide effective method and means for automatically sorting
such paper mixtures to segregate their respective components
for separate recycling; it being understood, however, that
the overall quality of a superior paper will not be
deleteriously affected, in a commercial sense, by the random
admixture of a small quantity of inferior paper therewith.
The invention takes cognizance of and is predicated
upon the fact that paper of one quality may be broadly
distinguishable from another by the ease or difficulty with
which they are respectively fragmented -- i.e. broken up
- into fragments. For example, mechanical pulp or groundwood
papers -- such as newsprint -- are generally more readily
fragmentable than the chemical pulp variety such as kraft.
Thus, a broad object of the invention is to provide
effective and economical method and means for selectively
sorting a paper mixture as described, to separate it into
componen*s ac^ording to their vulnerability to fragmentation
B-9602 P~2 CA - 2 -
, , . , . , . .. ~ . ,:
1~783Sl
herein equated with the quality of the paper.
The invention seeks, as another of its objects,
to provide such method and means for applying forces or
stresses to paper to break it into fragments and, as a collat-
eral object, to retrieve the resulting fragments; pre-sorted
and separated according to quality.
It is understandably necessary, of course, to
expose all parts of a paper mixture to the method and means
of the invention for the purpose of procuring maximum fragment
yield in minimum time. In the present instance, however, the
manipulation designed to procure such exposure serves
additionally to apply fragmentation forces to the mixture;
these being still further objects of the invention.
The invention achieves the foregoing and other
objectives by the provision of method and means for applying
fragmentation forces to a paper mixture as described; the
mixture being churned throughout, not only to procure exposure
of substantially all of its parts to the forces aforesaid but,
as well, to contribute more or less to said forces; the
churning and any other forces applied to the mixture being
continued until at least one of said mixture components has
been fragmented and eliminated from the mixture after which,
of course, the described operation may be resumed or continued
to fragment another or other components of the mixture.
The fragmenting operation described is carried out
in a mill consisting, basically, of an enclosure and an
impeller contained in the enclosur~ between which the paper is
sandwiched and churned as described; the forces applied to the
mixture being programmed as later described to procure
progressive fragmentation of the various components of the
B-9602 P/2 CA ~ 3 ~
`` 1~783S~
mixture. Because of their qualitative differences however,
certain of the paper components will fragment more readily
than others and the invention visualizes that the fragment
yield will be harvested at a suitable stage or at suitable
stages during the milling operation substantially between the
times when fragmentation of one quality of paper is completed
and before fragmentation of another has begun although strict
precision in this respect is not critically important to the
invention and is probably difficult to attain.
A selected embodiment of the invention exemplary
of its elements, parts and principles will now be described
with reference to the accompanying drawings wherein:
Fig. 1 -- is a schematic view of a mill in
isometric form with parts thereof
bro~en away to reveal structural
details on the interior thereof
and with other break lines along
its length; a projected addition
being shown in dotted lines;
Fig. 2 -- is a section along the line 2-2
of Fig. 1 with paper added
thereto to indicate the function
of the mill;
Fig. 3 -- is an isometric view of a detail
of the invention;
Fig. 4 -- contains a series of cross sectional
profiles of another part of the
invention, and
,
~_9602 p/2 CA
.
1al783Sl
Fig. 5 -- is a schematic view in isometric
and broken form of a part of the
invention with parts of the mill
housing.
The apparatus illustrated in the drawing is intended
to summarize the means contemplated by the invention while
the following explanations of its use and function is believed
and intended to typify the specific methods visualized.
As has been indicated, the invention achieves its
objectives by applying forces to a paper mixture which will
reduce its various components to fragments. Inasmuch as the
respective components vary in their vulnerability to the
fragmentation forces, one or another of such components may,
in the normal course of events be almost completely fragmented ~;
before fragmentation of others of the components commences;
the resulting fragments being harvested at this juncture.
In the broad concept of the invention, the operative -~
forces are programmed so that, ideally, each individual paper
component is relatively completely fragmented in its turn with
fragments of each being harvested, also in turn. In actuality,
however, some overlap between the fragmentation (and
harvesting) of "neighbouring" components is believed to
be inevitable. Subsequent reference herein to "complete"
fragmentation and "cqmplete" harvesting will therefore be
understood to contemplate such overlap.
The milling operation providing the forces by which
the components of the paper mixture are respectively fragment-
ed may be carried out in a mill M wherein all components of
the mixture are contemporaneously and indiscriminately exposed
to such forces; procuring progressive fragmentation of
- B-9602 P/2 C~ ~ 5 ~
~C}7835~
~ ,
respective ones of such components; the paper mixture being,
preferably, churned during such milling operations to
procure and ensure exposure of all of its parts and portions
to the fragmentation forces which are themselves augmented, or
supplemented, more or less, by the churning.
It should be explained and understood that the term
"churning" as utilized herein is meant to imply and include
all manipulation involved in the turning or tumbling of the
paper mixture to procure exposure of all of its parts to
the fragmentation forces. In turning it over, as will be
appreciated, the paper mixture is subjected to a wide range
of mechanical manipulations e.g. bending, twisting, flexing,
kneading, massaging, ~riction, pulling, tearing, crumpling
and probably others as well which, it is thought, serve or
co-operate to procure disruption and ultimate fragmentation
of the component papers within the paper mixture.
One manipulation which the invention seeks to avoid,
however, is the chopping or cutting of the paper which would
threaten the necessary selectivity of the invention as between
the various components and would, in addition, shorten the
paper fibres thereby degrading the paper harvest.
The mill M selected for the exemplary purposes of
this submission and shown schematically in Fig. 1 includes
an impeller 2 mounted for rotation in mill housing 4 on shaft
6 journalled as at 8-8 in the sides 10-10 of the housing 4;
the reference numeral 12 denoting a motor which may be coupled
in a known manner to shaft 6 for rotating the impeller 2
at a desired speed.
In this instance said impeller 2 is either partially
or completely enclosed by heavy wire screening 14 with a mesh
- B-9602 P/2 CA _ 6 -
1~78351
dimensioned to accomodate sifting of the paper fragments
therethrough.
The screening 14 is spaced from the impeller 2
leaving space 16 within the enclosure for the accommodation
of paper mixture and fins 18 extending radially from impeller
2 and spaced about its circumference serve as scoops for
engaging and moving the paper mixture in space 16 when
impeller 2 is rotated whereby the paper is not only churned
as above described but is also scrubbed against screen 14 to
procure or aid in procuring its fragmentation.
It will be apparent that several factors come into
play and have a bearing of more or less importance on the
speed and efficiency of paper fragmentation in or by the
mill M.
Among more obvious of such factors is the rotary
speed of impeller 2 as well as the length of time that the .
paper is exposed to the fragmentation forces in mill M.
Of additional and collateral significance is the ~'r`
width of space 16 around impeller 2; the amount of paper
crammed into the space; the moisture content of such paper;
the cross-sectional shape of fins 18; the extent of their
projection into space 16; the quality of the paper, and other
like factors of more or less consequence to which further
reference may be made herein.
The appropriate balancing of these and other factors
to procure an optimal result in any given instance, herein
defined as a program, ensures the most effective and economical
function of mill M.
It may now be explained that screening 14 provides not
only an effecti~e solution to the requirement for an impeller
B-9602 P/2 CA - 7 -
.: ` ` ` " ~
1078351
`
enclosure but also provides numerous openings through which
paper fragments 20 produced by said forces may be eliminated
and harvested. Obviously screening 14 is one of the many
kinds of foramenous media which may serve to enclose impeller
2 and afford elimination facilities for fragments 20.
For an understanding of the function and performance
of mill 4, it may be assumed, for example, that a given paper
mixture has three components differing from each other in their
respective vulnerability to fragmentation under the forces
developed in mill M which have been suitably programmed for
the purposes of the invention.
When and as this paper mixture is subjected to the
milling operation the first of its three components (which is
most vulnerable to the fragmentation forces) will begin first
to break up with its resulting fragments 20 being eliminated
through screening 14 as in Fig. 2. At a giuen point or stage
in the milling operation, measurable in time, for example,
the first paper component may be assumed to have been, in
theory, completely fragmented and harvested. Only insofar as
it is practicable, however, the programming should confine
the fragmentation to one grade of paper at a time to minimize
adulteration of the harvest by stray fragments of other grades~
At all events, continued milling will then procure fragment-
ation of the second component and when that is co~mpleted and
the resultant fragments harvested the paper remaining in the
mill will, obviously, constitute the last component of the
mixture. In practice, of course, and it will be understood
that, one or more additional components may be included in
the mixture between the second and last.
It may be, of course, that the second or any
B-9602 P/2 CA - 8 -
1C~7835i
,
subsequent component will~require a different programming of
the forces for its fragmentation. In such eventuality, of -
course, two obvious alternatives would be available, namely,
(a) either to re-program the forces to act on said second
or subsequent component in the same mill M or (b) to move
the unfragmented paper from mill Ma where the first component
was treated, to a second mill Mb, programmed more
appropriately to that component.
These alternatives are represented in Fig. 1 of the
drawing wherein mill M appears as an elongated machine and
wherein fins 18 are affixed to impeller 2 in a spiral
inclination whereby rotation of impeller 2 will not only churn
the paper mixture trapped between impeller 2 and screen 14
but will also-advance it from the input end of mill M at the
left of this view to the other end.
As shown in this Fig. 1 said mill M is divided into
three units Ma, Mb, and Mc by two pairs of broken lines to
imply discontinuity indicating that the units Ma, Mb, and
Mc or any neighbouring two may be separated or merged into
one. In practice it will be obvious that the respective
units need not be disposed adjacent or beside each other when
they are separate.
~ins 18 may be spiroid as shown in this view or may,
of course, be rectilinear as shown in Fig. 3. Likewise they
may be continuous throughout the length of the impeller 2 or
may be interrupted, leaving gaps 22, and studs 24, suitably
affixed to other parts of mill M, may be positioned to pass
through gaps 22 when the impeller 2 is rotated; coincidentally
pulling paper through gaps 22.
Cross-sectionally, the fins 18 may have a variety
B-9602 P/2 CA ~ 9 ~
~783Sl
of shapes such as those shown in Fig. 4; care being taken to
shape the fins to avoid cutting the paper.
It will now be apparent that there are numerous ways
in which mill M may be constituted according to the invention
to render it most effective for the fragmentation of the
paper it may be called upon to handle.
Reference has already been made to the fin structure.
In addition, the force with which paper is rubbed along screen
14, may also be affected by varying the rotary speed of impeller
2 which may be achieved in any of many known ways or by means
of known controls suggested for example by the block element
25 in Fig. 1.
Paper mixture may be fed to mill M by an auger
feeder 26, for example, which delivers ;the mixture into a
plenum 28 above impeller 2; the rate of feed being another
in the factors governing the efficient operation of mill M
since it has a bearing on the quantity of paper crammed into
space 16.
A still further factor of major importance is the
time during which the paper remains in the mill M.
Obviously, the importance of any single factor is
dependent upon others.
The time factor, for example, may be lessened or
increased by varying the impeller speed or the rate of feed.
The ràte at which paper is fed into mill M is also variable
with appropriate compensation in other factors.
It is the balance of these factors, however,
according to the specific papers to be fragmented and the
moisture content thereof which is herein compendiously
referred to as a program. Ideally, the practice of the
invention is intended to be confined to "dry" paper having
B-9602 P/2 CA - 10 -
1078351
. ,
a moisture content not substantially exceeding 60%.
In the use of the present invention, paper mixture
to be sorted thereby is fed into hopper H (Fig. 1) from which
it is transferred by auger feeder 26 into plenum 28 where it
5 is captured by fins 18 on the rotating impeller 2 and brought
down into space 16 where it is subjected not only to vigorous
churning but also scrubbed against screening 14 resulting in
its fragmentation and elimination of its fragments thrQugh
screening 14 whose mesh is appropriately dimensioned to permit
sifting of the fragments therethrough.
Obviously, the component of the mixture most prone
to fragmentation will be the first to be eliminated as afore-
said; other components being thereafter fragmented and
eliminated, in the same manner, in turn, as the milling of
the residue is continued either with the same or alternative
programming.
The described construction of mill M has been confined
to basics inasmuch as there may well be many structural forms
in which the inventive concept is capable of successful
embodiment.
For example, it will be appreciated that the invention
achieves its objectives by churning relatively dry paper
between an impeller 2 and an enclosure such as screening 14
with a mesh large enough to accomodate sifting of resultant
fragments 20 therethrough but not so small as to retain them in
the enclosure for further dimensional reduction. In this
embodiment, the churning is accomplished in the traditional
and obvious manner by rotating the impeller 2 inside stationary
screening 14. In appropriate circumstances, however, recourse
may be had to the obvious alternatives of rocking or rotating
the screening 14 instead of or in addition to the impeller 2
B-9602 P/2 CA - 11 -
~78~5~
.:
especially if it (screening 14) is continued all around impeller -
2 to enclose plenum 28 as well as space 16 as suggested by the
broken lines in Fig. 2.
Fins 18 are the elements of choice which enable the
impeller 2 to capture paper in the plenum 28 and transport
it to space 16 as well as to aid in the churning of the paper
and in scrubbing it against screening 14. However, there is
wide latitude on the cross-sectional profiles of fins 18 as will
be obvious from Fig. 4 and there is also some latitude in
their general form as, for example, the discontinuous form
shown in Fig. 5 and the sinuous or spiroid form shown in
Fig. 1 which tends to propel paper mixture within the
enclosing screen lengthwise of the impeller 2 while the latter
is rotating.
It will be understood and appreciated incidentally,
that the introduction of paper into plenum 28 on the one hand
and its advancement through the mill M may be effected in
various ways of which the auger feeder 26 and the spiroid fins
1~ of Fig. 1 are merely representative.
Thus, in Fig. 1 hopper H is shown repositioned (in
dotted lines) at the left of this view; it being understood
that auger 26 may be substantially shortened from the length
shown. ;
The advance of the paper from left to right of mill
M as pictured may be effected or aided by slanted deflectors
30 attached to screening 14 more or less as shown in Fig. 3 or
in fact the paper may be ad~a~ced ln an~ other o~ ~e many
ways known.
It is within these parameters that the invention
is constituted and of course, the specific media by which
the invention is practiced are factors bearing generally on
B-9602 P/Z CA - 12 - ;
~078351
the programming of the final equipment.
To avoid misunderstanding it is re-iterated that
while the submission speaks of complete fragmentation and
complete harvesting of the resulting fragments, the fact is
that this is a most impractical limitation since, in many
instances, as and while paper of one quality is being reduced
to fragments, stray scraps or fragments of another quality
may develop and mingle therewith. While proper programming
will confine these stray fragments to tolerable limits so
that their effect will be negligible, nevertheless use
herein of the word "complete" in connection with
fragmentation and harvesting is not intended and should not
be read as absolutely complete but only as relatively
complete.
It will be recalled that the paper mixtures
processed by the invention may be derived from a varlety
of sources in which situation it will be understood that
they may contain substances other than paper and it will
be, therefore, further understood that such substances which
are incapable of fragmentation may be recovered from the
enclosure after fragmentation of the other constituents
of the mixture.
The true scope of the invention is therefore as
set forth in the appended claims which now follow.
B-9602 P/2 CA - 13 -
