This invention relates to the field of secondary materials
processing and more particularly to grinding equipment for recycling waste, defective
or discarded during production car tires and rubber-containing production wastes,
etc in order to obtain reusable material.
Background of the Art
Worn out industrial rubber articles account for a considerable
amount of products of human activity, which contaminate the environment. One of
the most urgent is the problem of utilization of worn out tires, especially large-size
tires, due to the fact that only a small quantity of such tires undergoes recycling,
which results in their accumulating at dump sites.
The simplest example of utilization of waste rubber articles
is their burning which is widely used for worn out tires. However, this utilization
method is known to substantially pollute the environment.
Recycling of industrial rubber articles and obtaining rubber
crumb by known methods as a rule includes the following operations: cutting articles
to pieces, grinding, removing reinforcement metal and textile elements from the
rubber, further grinding of rubber crumb and separating it from small pieces of
reinforcing elements. Used in grinding are: cutters, roller breakers, rotor-knife
crushers, mills and shredders. Removing metal cord from rubber is generally performed
by magnetic separators.
It is known to use cryogenic technology for embrittlement
of rubber by cooling it down to the glass transition temperature and subsequent
grinding (utility model patent
for "Apparatus for tire recycling" patent application
for "Apparatus for cryogenic recycling of polymer materials ", patent
for "Apparatus for grinding worn out tires", patent application
for "Apparatus for low temperature grinding", patent application
for "Line for rubber waste recycling").
The common disadvantage of cryogenic recycling systems
is high energy consumption connected with a need to obtain and maintain low temperatures
in the operating chamber including the stage of mechanical grinding of articles
into fragments. Besides, carrying out the low temperature process of rubber grinding
requires application of sophisticated equipment, which is capable of operating in
such conditions, thermal insulation of the whole system, insulation of cooled crumb
from the atmospheric air and solution of a number of difficult technical problems.
There have also been known plants for grinding industrial
rubber articles by mechanical breakage. For example there is a line known for recycling
of worn out tires (patent
), which comprises a machine for cutting tires to pieces, hammer crusher,
finely dispersed breaking machine, machine for removal of cord units and sorter
for fractioning of rubber pieces and crumb.
There has also been known a processing line for recycling
of worn out tires, which comprises a debeading machine for preliminary removal of
bead rings from the tires, machine for cutting tires to pieces, hammer crusher,
finely dispersed breaking machine, machine for removal of cord units and sorter
for fractioning of rubber pieces and crumb (patent
The disadvantage of known processing lines is their low
reliability and inefficient operation of equipment with respect to energy consumption,
which is stipulated by application of the hammer crusher, which sets the high requirements
for the material feed modes. Besides, one of the serious disadvantages is referred
to low quality of the finished product - rubber crumb, which contains elements of
textile and metal cords, as well as multi-staging processing and a wide scatter
in obtained fractions.
There has also been known a line for recycling of worn
out tires, which comprises machines connected by transportation facilities: a machine
for preliminary grinding of tires, machine for obtaining big rubber crumb and machine
for obtaining finely dispersed crumb, these two machines equipped with systems removing
the textile cord, and between them there is a magnetic device installed above the
transportation facility (patent
). The removing system is an air discharge ventilation system designed
as successively installed dust fan, cyclone and textile cord removal filter.
The disadvantage of this known line is low reliability
and low quality of the finished product.
There is also known a line (patent
) for utilization of worn out tires, which comprises machines connected
by transportation facilities: a machine for preliminary grinding of tires, machine
for obtaining big rubber crumb and machine for obtaining finely dispersed crumb,
these two machines equipped with systems removing the textile cord, and between
them there is a magnetic device installed above the transportation facility. The
line is additionally equipped with a machine for radial cutting of tires and an
additional machine for separating bead ring metal parts. These machines are connected
by transportation facilities with a machine for grinding tires. The line is equipped
with an additional magnetic device installed above the transportation facility after
the machine for obtaining finely dispersed crumb. The line is equipped with additional
devices for removal of textile cord, installed after magnetic separators. The textile
cord vacuum system is executed in the form of a forced extract-and-input ventilation
The common disadvantage of mechanical processing methods
of rubber containing articles is emission of high quantity of environmentally harmful
volatile products from rubber heated up in the process of mechanical grinding. Moreover,
the mechanical methods are characterized by high energy consumption and do not provide
effective processing of rubber containing articles reinforced with metal, for example
tires with metal cords, and do not allow obtaining quality secondary material, which
is rubber crumb.
The closest to the herein proposed invention, in other
words a prototype, is a device for disintegration of materials (useful model patent
for "Device for disintegration of materials", published in 2005). The
said device is equipped with a preliminary material preparation system, material
forced feed system, fan system for cooling of operation area and working tool as
well as a system for removal and separation of disintegration products. The device
also comprises an impact type processing tool connected with the drive, which affects
the processed material as a shock action with high supersonic frequency. The preliminary
material preparation system is implemented as a die hole installed in the fixed
support, designed as a table shaped and profiled according to its side planes of
depression waves. The material forced feed system is executed as a combination of
rotating rollers feeding the processed material into the die hole; the inlet hole
of the latter is positioned with a minimum gap in relation to working tool. The
removal and separation system of disintegration products comprises a fan, cooler
and magnetic separator.
The disadvantage of the said device is the fact that the
structure of the impact type cutting tool in combination with operating parts which
do not have air gaps between each other does not allow increasing the degree of
dispersion of processed materials and as a result decreases the processing efficiency.
Moreover, the preliminary preparation system of material for grinding designed as
a die hole does not enable to increase homogeneity of the processed material and
only one fan cooling system available does not provide sufficient air flow into
the operating area and working tool, which negatively affects the processing efficiency
and leads to deterioration of cooling conditions for the tool, and, consequently
to decreasing its endurance.
Disclosure of the Invention
Objects of the present invention are to overcome the above
mentioned disadvantages, and to increase the efficiency of grinding industrial rubber
articles by improving the tool cooling system, which enables to increase the processing
efficiency, homogeneity and degree of dispersion of processed ground material.
The said objects are attained in a line for grinding materials,
in particular worn out tires, comprising the following equipment placed in a processing
sequence: preliminary material preparation system, a mechanism for forced feeding
material to the grinding area, a supporting table, a disintegrator provided with
horizontally positioned cylindrical working tool, and ventilation system which is
used for cooling the tool and removing a ground product and is provided with discharging
air ducts, a fan and a magnetic separator, in accordance with the claimed invention
the line is additionally provided with a sorter installed in the processing chain
after the disintegrator and embodied in the form of an inclined wire mesh filter.
Other distinguishing features of the proposed line are
the location of the supporting table operating surface in the horizontal plane coinciding
with the axis of the disintegrator working tool, the lower part of the table, facing
the tool is embodied in such a way that it is equidistant to the tool, its radius
exceeding the radius of the tool by 2-5 mm, its vertical plane shaped as an arc
is limited by an angle of 45-90°, and the said equidistant part of the table
is provided with horizontal air channels across its width.
A further distinctive feature of the proposed invention
from the prototype is the preliminary material preparation system comprising the
following units positioned in processing sequence: a conveyor, a material radially
cutting machine and a mechanism for arranging cut parts into a strip, the mechanism
for forced feeding material to the grinding area designed with at least two lower
and two upper operating rollers installed successively in the horizontal plane,
the upper rollers are capable of vertical moving and the operating surface of the
rollers is grooved.
Still further distinguishing features of the proposed structure
are a disintegrator tool made as a set of disk cutters and installed in axial alignment
with air gaps between them, each operating part of these cutters has a grooved surface,
the grooves of each cutter located against the grooves of adjoining cutters chequer-wise
and the cutting edge of each groove having a lenticular shape.
Besides, the line is provided with an additional supply
air duct connecting the grinding area to the atmosphere, and is equipped with a
removable bunker installed in the lower part of the sorter.
Contrastive analysis with the prototype shows that the
claimed invention is characterized by new elements, their location relative to each
other, their interconnections and the form of execution.
The performed patent search has shown that at the present
time there has been known no line for grinding materials, mainly worn out tires
having the same combination of essential features as the proposed one.
The execution of the preliminary material preparation system
in the form of successively installed conveyor, a machine for radial cutting of
materials and mechanism for arranging the cut parts into a strip as well as the
sorter installed in processing chain after the disintegrator and designed in the
form of inclined wire mesh filter, makes it possible to perform cutting and straightening
of the cut parts prior to grinding, separation of ground parts by size on the sorter
and removal of material crumbs falling beyond the required size, which settle down
in the removable bunker installed in the lower part of the sorter, which, in its
turn, enables to increase homogeneity of processed rubber crumb.
Supplying the claimed line for grinding material with an
additional air duct connecting the lower and upper grinding areas with the atmosphere,
execution of the disintegrator tool as a set of disk cutters with grooved operating
surface, installed with air gaps between the cutters as well as making the lower
part of the supporting table equidistant to the tool, provides additional air supply
by the duct and enables to supply more materials for processing per time unit, which
will increase the line processing capacity and the dispersion degree of the processed
The chequer-wise location of grooves of every cutter of
the disintegrator operating tool against the grooves of adjoining cutters will make
it possible to reduce loads in the tool drive due to reduction of dynamic impact,
which will increase the endurance of the tool and as a result the operation efficiency
of the grinding line.
The execution of the cutting edge of the operating tool
in a lenticular form has been selected by empiric methods and makes it possible
to perform more uniform grinding of material, which increases its homogeneity. Besides,
providing the operating part of disc cutters with grooves improves cooling conditions
for the tool and does not allow their tarring from industrial rubber articles due
to high temperature impacts occurring in the grinding area, which eventually will
increase the tool operation rate.
The execution of lower part of the table equidistant to
the tool with the radius exceeding the radius of the tool by 2-5 mm, and in the
shape of arc limited by an angle of 45-90°, provides optimal conditions for
air supply to the tool and as a result their better cooling. In case of overshooting
the mentioned limits the amount of passed air decreases.
Installation of the upper rollers with a possibility of
vertical movement makes it possible to perform regulation of the gap between the
lower and upper rollers decreasing it in the course of movement of material, which
will ensure reliable fixation of materials being ground.
In this regard all above mentioned features distinctive
from the prototype make it possible to increase the efficiency of grinding material
including worn out tires.
The abovementioned facts prove that the combination of
features distinctive from the prototype makes it possible to apply the claimed technical
solution for recycling waste, defective or discarded during production car tires
and rubber-containing production wastes in order to obtain material suitable for
further use, for example, in road construction, in manufacture of structural, thermal
insulation and anticorrosive materials.
Brief Description of the Drawings
The claimed invention is illustrated with the accompanying
Description of the Preferred Embodiments
Fig.1 shows a schematic line for grinding
Fig.2 shows a view A of Fig.1
(supporting table with disintegrator).
Given below is a particular example of the structural embodiment
of the claimed invention.
The claimed line for grinding materials, mainly processing
of worn out tires comprises installed in a processing sequence a preliminary material
preparation system 1, a mechanism 2 for forced supplying the material to the grinding
area, a supporting table 3, a disintegrator 4 (
Polytechnic Dictionary, issued by Soviet Encyclopedia, M., 1980, page 140
), provided with horizontally positioned cylindrical working tool, a sorter
Polytechnic Dictionary, issued by Soviet Encyclopedia, M., 1980, page 223
) and a ventilation system for cooling of the tool and removing a ground
The preliminary material preparation system comprises successively
installed and connected by transportation facilities, for example, a conveyor 7,
a machine 8 for radial cutting of tires, for example debeading machine (see, for
and others), a mechanism 9 for arranging the cut parts into a strip (see
Polytechnic Dictionary, issued by Soviet Encyclopedia, M., 1980, page 414
The mechanism 2 for forced supplying of material subjected
to processing to the grinding area is executed with at least two fixed lower rollers
10 installed successively in the horizontal plane and located opposite to them at
least two upper 11 leading rollers capable of vertical moving, for example loaded
with springs 12.
Such a structural design of the mechanism 2 for forced
supplying make it possible to provide a regulated gap between the respective upper
and lower rollers, which reduces in the course of movement of material to grinding
area. All the rollers 10 and 11 have grooved operating surface.
The supporting table 3 has an operating surface located
in the horizontal plane coinciding with the axis of a working tool 5 of the disintegrator
4. Facing the tool 5 the lower part of the supporting table 3 is equidistant to
the tool, its vertical plane shaped as an arc limited by the central angle &agr;
= 45-90° with radius "R" exceeding radius "r" of the tool by 2-5 mm. In the
above mentioned lower part of the supporting table 3, along its whole width there
are horizontal channels 13 providing air supply.
The working tool 5 of the disintegrator 4 is executed as
a set of disk cutters having the grooved operating surface and installed with air
gaps between them. The operating part of every disk cutter has a grooved surface.
The grooves of every cutter of the disintegrator operating tool are located against
the grooves of adjoining cutters chequer-wise and have a lenticular shape of the
The sorter 6 is embodied in the form of an inclined to
air flow wire mesh filter, which has a removable bunker 14 in its lower part.
The ventilation system for cooling the tool and removing
ground product is designed as a supply and exhaust system comprising discharging
air ducts 15 connecting a fan 16, the sorter 6 and a magnetic separator 17 (
Polytechnic Dictionary issued by Soviet Encyclopedia, M., 1980, page 471
), filters 18 for separation of processed components of recycled tires
and bunkers 19 for collecting metal wastes and ground rubber crumb (disintegrat).
The grinding area (of the disintegrator 4) is equipped with an additional air duct
20 connecting the upper and lower parts of the area with the atmosphere.
The line for grinding worn out tires operates in compliance
with the following method.
The worn out tires subjected to processing are loaded by
a loader (not shown in the drawing) onto the conveyor 7 delivering them to the machine
8 for radial cutting where tires along with metal cords are cut to pieces which
are further delivered to the mechanism 9 arranging them into strip. The straightened
pieces are fed into regulated gap between the upper 11 and lower 10 rollers of the
mechanism 2 for forced supplying, which is set in advance for a certain size due
to movement of the upper 11 rollers in the vertical plane, with the given gap decreasing
in the course of material movement to the grinding area which results in stable
fixation of a tire between rollers.
The cut parts are hooked by grooved operating surfaces
of the rollers 10 and 11 and delivered to the supporting table 3 and disintegrator
4. Passing through the disintegrator the tire pieces are ground by the disc cutters
5 along with metal cord into rubber crumb which is lifted by the air flow generated
by the fan 16 and coming from the additional air duct 20 connected with the atmosphere.
Taken by the flow generated by the fan 16, the mixture
of air with grinding products of a tire (rubber) passing through the discharging
air duct 15, comes to the sorter 6, where rubber and crumb are fractioned by size,
with big pieces removed by their own weight, dropping off the inclined wire mesh
filter into the removable bunker 14. Then the mixture of air and crumb comes into
the magnetic separator 17 where separation of metal cord parts from the flow of
finely dispersed rubber crumb occurs with further delivery of the mixture into the
separate bunkers 19.
The claimed line provides increasing efficiency of grinding
industrial rubber parts including worn out tires and allows complete recycling of
a tire including both tread and side parts. The line has high efficiency due to
improvement of cooling of the operating tools and grinding area.