Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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1 BRIEF DESCRIPTION OF THE DRAWINGS
2 Fig. 1 is a side cross-sectional view of a cracking trough of recycling
3 apparatus for organic solid wastes in accordance with the present invention;
4 Fig. 2 is a top cross-sectional view of the cracking trough along line 2-2
in Fig.
1;
6 Fig. 3 is an enlarged view of part B of the cracking trough in accordance
with
7 Fig. l;
8 Fig. 4 is an enlarged view of part C of the cracking trough in accordance
with
9 Fig. 1; and
Fig. S is a schematic explanatory diagram showing operating processes of the
11 recycling apparatus for organic solid wastes.
12 BACKGROUND OF THE INVENTION
13 1. Field of the Invention
14 The present invention relates to recycling apparatuses for organic solid
wastes, and more specifically to recycling apparatus, which are operated
efficiently
16 and continuously to decompose waste tires, waste rubber, polyester (PE),
polyvinyl
17 chloride (PVC) and lubricant oil.
18 2. Description of Related Art
19 Generally, there are two types of waste tire recycling methods:
The first method is cutting waste tires into pieces and separating the steel
21 wires, nylon and rubber. The separated rubber is then re-utilized to
manufacture
22 recycled rubber. Since the recycled rubber is of inferior quality and can
not be reused
23 to manufacture new tires, the value of the recycled products in not high
enough to be
24 economically attractive.
The second method is mixing an appropriate ratio of catalysts with the cut
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1 small pieces of the recycled waste tire under a condition of 230-
500°C and double the
2 atmospheric pressure, to cause cracking and trough distillation to produce
oils, carbon
3 black, and residues. Additionally, a mixture of organic gases from cracking
is
4 fractionated into light oil, diesel oil, and heavy oil, etc., which are high
economic
valued by-products. In this second method, the waste tire is fully utilized so
that the
6 second method is more economically attractive than the first method.
7 While the existing waste tire cracking technologies may be maturing, there
8 has not been practical technical demonstration towards the integrated
planning of
9 industrial application. All existing cracking technology is operated on a
single batch
basis, i.e., both cracking and recovery of the fuel mixture are proceeded a
batch at a
11 time with no continuity between each batch. Since every cracking tank is
operated
12 independently, the cracking technology is hard to integrate in the recovery
equipment
13 and produces a lot of problems for operation and management. Additionally,
14 practicing the cracking technology also requires more manpower and hence
has a
high cost of operation.
16 In addition, the cracking technologies in present use the heat generated
from
17 burning oil for thermal cracking. Hot gas generated from burning is then
directed to
18 peripheral pipes laced inside the cracking tank to provide indirect heating
to the waste
19 tires. However, the heat transfer characteristics of the pipes are
inefficient and the heat
is not fully utilized.
21 During the thermal cracking, a mixture of the gases is produced and
22 exhausted to a recovery line. As cracking proceeds toward completion, the
gas
23 production is reduced and is no longer discharged to the recovery line, the
24 temperature of each cracking unit may be reduced, and then the residues can
be
removed. However, when the cover of the cracking tank is opened, remaining
gases
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1 escape to the atmosphere causing not only air pollution but also affecting
operators'
2 health.
3 Therefore, the present invention is raised to mitigate and/or eliminate the
4 existing problems of the cracking technology.
SUMMARY OF THE INVENTION
6 A first objective of the invention is to provide recycling apparatuses for
7 organic solid wastes such as waste tires, waste rubber, polyethylene,
polyvinyl
8 chloride, and lubricant oil, wherein the recycling apparatuses are operated
9 continuously to achieve high efficiency.
A second objective of the invention is to provide recycling apparatuses for
11 organic solid wastes that have efficient heat utilization.
12 A third objective of the invention is to provide recycling apparatuses for
13 organic solid wastes that exhaust remaining gases from inner tanks to avoid
ill effects
14 to operators' health.
A fourth objective of the invention is to provide recycling apparatuses for
16 organic solid wastes that prevent self ignition of cracking gases.
17 A fifth objective of the invention is to provide recycling apparatuses for
18 organic solid wastes that facilitate the thermal cracking efficiency.
19 Other objects, advantages and novel features of the invention will become
more apparent from the following detailed description when taken in
conjunction
21 with the accompanying drawings.
22 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
23 Recycling apparatuses for organic solid wastes such as waste tires, waste
24 rubber, polyethylene (PE), polyvinyl chloride (PVC), and lubricant oil,
that the
recycling apparatuses mainly comprise a combustion chamber (A), multiple
cracking
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1 troughs (Al,...An), and multiple pluralities of controlling valves (Vcs,
Ves, Vis, and
2 Vss).
3 With reference to Figs. 1 and 2, a cracking trough (Al) is composed of a
heat
4 insulation tank (1), an inner tank (2), and a top cover (3).
5 The heat insulation tank ( 1 ) is constructed in a circular shape using heat
6 durable bricks to form an inner wall thereof. A U-shaped dividing wall (11)
is
7 vertically formed- along the inner wall of the heat insolating tank ( 1 ) to
support the
8 inner tank (2) and construct an isolating layer (112). A groove (12) is
defined in a top
9 surface of the heat insulation tank (1) for mating with the inner tank (2).
An inlet (13)
and an outlet ( 14) are oppositely defined in the insulation tank ( 1 )
perpendicular to the
11 dividing wall ( 11 ) (see Fig. 2) and communicate with the isolating layer
( 112) of the
12 insulation tank ( 1 ).
13 The inner tank (2) is a circular shell mounted on the dividing wall ( 11 )
and
14 has an outer diameter smaller than an inner diameter of the heat insulation
tank ( 1 ) so
as to be received in the heat insulation tank ( 1 ). A circular overhang (21 )
is formed
16 laterally and outwardly from a top periphery of the inner tank (2) and has
a flange (22)
17 formed on an under surface thereof to correspond to the groove ( 12) of the
heat
18 insulation tank ( 1 ). Therefore, the inner tank (2) is firmly supported by
the heat
19 insulation tank ( 1 ) when received inside the heat insulation tank ( 1 ).
A middle
partition (24) extending laterally inside an inner space of the inner tank (2)
divides the
21 inner space of the inner tank (2) into a lower compartment (241) and an
upper
22 compartment (243). Multiple heating tubes (25a, 25b) are vertically secured
on the
23 middle partition (24) in a radial configuration, wherein a first heating
tube (25a) is at a
24 center of the upper compartment (243) and a plurality of second heating
tubes (25b)
are evenly distributed around the first heating tube (25a) at a half way point
of the
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1 radius of the inner tank (2). Each heating tube (25a, 25b) has multiple
heating plates
2 (251) attached around outer peripheries of the heating tubes (25a, 25b) and
multiple
3 tapered connectors (252) formed on the top of the heating plates (251).
4 With reference to Figs. 1 and 3, the top cover (3) covers the inner tank (2)
and
has multiple air seals (31 ) partially embedded along it's edge facing down to
contact
6 with the overhang (21 ) of the inner tank (2) so as to make the inner tank
(2) airtight.
7 Additionally, for each individual cracking trough (A1), the top cover (3) is
fastened to
8 the inner tank (2) by screws (4).
9 With reference to Figs. 1 and 4, multiple recesses (32) are defined in the
bottom face of the top cover (3) to mate with the corresponding tapered
connectors
11 (252) of the heating tubes (25a, 25b). Additionally, multiple washers (253)
are
12 secured inside the recesses (32) and sandwiched by the top cover (3) and
the tapered
13 connectors (252) to provide an airtight effect for the heating tubes (25).
A network of
14 pipelines is communicated with the cracking trough (A 1 ) at the top cover
(3), wherein
the pipelines connect to the multiple pluralities of three-way recycling
valves
16 (Vs 1. . . Vsn), three-way cooling valves (Vc 1. . . Vcn), pressure
releasing valves
17 (Vi 1. . . Vin), and exhausting valves (Ve 1. . . Ven).
18 Now referring to Figs. 1 and 5 showing the recycling apparatus for organic
19 solid wastes in assembly, each cracking trough (A1) is connected to the
multiple
three-way valves (Vs, Vi, Vc, Vn). A heat supply pipe (5), a recycle pipe (6),
a
21 discharge pipe (7), and exhaust pipe (8) are connected respectively in
parallel as
22 shown in Fig. 5. The heat supply pipe (5) is connected to the combustion
chamber (A),
23 which provides heat to the cracking troughs (Al ...An). The recycle pipe
(6) is
24 connected to a heat exchanger (B), which is connected to a store tank (C)
to collect
condensed liquid in the heat exchanger (B) and a return pipe (9) to recycle
oil gases to
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1 the combustion chamber (A). The discharge pipe (7) is connected to a cooling
heat
2 exchanger (D), which is connected to a vacuum pump (E). The vacuum pump (E)
is
3 connected back to the combustion chamber (A). The exhaust pipe (8) is
connected to
4 an air pollution controlling apparatus (F) and then to a fan (G) and a
stack. (H).
In order to understand operational procedures of a plurality of the recycling
6 apparatus for organic solid wastes in assembly, a detailed illustration of
Fig. 5 is
7 described as follow:
8 First, turning off all the valves of the plurality of cracking troughs (Al
...An)
9 and then removing the inner tanks (2) out from the heat insulation tank ( 1
) to load
waste tire pieces inside the inner tanks (2). Lowering the inner tanks into
the heat
11 insulation tank (1) and closing the top covers (3). Opening all evacuating
ends of the
12 three-way recycling valves (Vs 1. . . Vsn) to evacuate air from the inner
tanks (2) until
13 the pressures in the inner tanks (2) fall below 0.05 atm. Under this low-
pressure
14 condition, self ignition of gas mixtures after cracking is eliminated
because of a
lackof oxygen and other oxide gases such as nitrogen oxides, sulfur oxides.
Then
16 closing the evacuating ends of the three-way recycling valves (Vsl ...Vsn)
and
17 opening recycling ends of the three-way recycle valves (VsI...Vsn) to
reflow the
18 initial cracking gas back into the inner tanks (2). In this way, the
thermal cracking rate
19 of the waste tires is increased.
Then opening gas inlet ends of the three-way cooling valves (Vc 1. . . Vcn),
21 which are connected to the cracking troughs (A1...An), and the exhausting
valves
22 (Vel . ..Ven) connected to the releasing pipe (8) at the same time to
adjust the flow rate
23 in balance in the cracking troughs (A 1. . . An). Additionally, turning on
an air
24 controlling valve (Va) and a fuel controlling valve (Vf) of the combustion
chamber (A)
to adjust an suitable air/fuel ratio so as to make the air and fuel mixture
burning
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1 completely in the combustion chamber (A) to produce heating gas. The heating
gas
2 produced from the combustion chamber (A) is channeled through the heat
supply pipe
3 (5) to all heat heating tubes (25a, 25b) of the cracking troughs (A1...An)
arranged in
4 parallel so that each heat dissipation tube (25) heats up the inner tank (2)
indirectly.
Then, the heating gas is exhausted by the exhaust pipe (8) from the cracking
troughs
6 (Al ...An) to the air pollution controlling equipment (F), and finally
discharged via
7 the fan (G) and the stack (H). Therefore, after utilizing the heating gas
from the
8 combustion chamber (A) to heat the cracking troughs (A 1. . . An), all
polluting
9 compounds containing sulfur, carbon, nitrogen, and chloride are removed
through the
air pollution controlling equipment (F) from the heating gas. In compliance
with air
11 emission standards, the heating gas is safe enough to be discharged into
the
12 atmosphere.
13 When the heating gas from the combustion chamber (A) is directed into the
14 inner tanks (2), in order to maintain a desired cracking temperature, the
three-way
cooling valves (Vc 1. . . Vcn) are adjusted to open an air inlet ends to
provide a suitable
16 amount of cool air to mix with the heating gas, and therefore reach the
desired
17 cracking temperature. Under an appropriate temperature, the waste tires in
the inner
18 tanks (2) of the cracking troughs (Al ...An) are melted into viscous fluid
with low
19 fluidity, wherein thermal cracking begins and gaseous compounds are
released. At
this moment, the evacuating ends of the three-way recycle valves (Vsl ...Vsn)
21 connected to the inner tanks (2) are opened to allow the cracking gases
from cracking
22 troughs (Al ...An) be directed through the recycle line (6) to the heat
exchanger (B).
23 In the heat exchanger (B), the cracking gases are cooled, wherein oil gases
containing
24 in the cracking gases are condensed into liquid and collected in the store
tank (C). The
condensed liquid is an oil mixture, which can be separated into valuable
products
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1 such as light oil, gasoline, kerosene, diesel oil, and heavy oil etc.
Remaining cracking
2 gases are incondensable and re-utilized through the return pipe (9) and
directed back
3 to the combustion chamber (A).
4 During thermal cracking in the cracking troughs (A 1. . . An), as the
cracking
gases are produced, pressure is built up inside the inner tanks (2). The
pressure inside
6 the inner tanks (2) is monitored to determine if pre-set values are reached,
whereby
7 the gas inlet ends of the three-way cooling valves (Vs 1. . . Vcn), the
recycling ends of
8 the three-way recycle valves (Vs 1. . . Vsn) and the exhaust valves (Ve 1. .
. Ven) are
9 opened to maintain the appropriate temperature range in the inner tanks
(2).] When
the cracking gases are degenerated and the pressures drops to equal or below
the
11 pre-set value, then the gas inlet ends of the three-way cooling valves (Vc
1. . . Vcn) and
12 the recycling ends of the three-way recycle valves (Vs 1. . . Vsn) are
opened. At the
13 same time, outlet ends of the three-way cooling valves (Vc 1. . . Vcn) and
evacuating
14 ends of the three-way recycle valves (Vs 1. . . Vsn) are opened in
accompaniment with
starting the vacuum pumps (E) to suck out the cracking gases from the inner
tanks (2)
16 to achieve a vacuum condition inside the cracking troughs (Al ...An). The
evacuated
17 cracking gases are directed through the discharge pipes (7) to the cooling
heat
18 exchanger (D), and then re-utilized through the return pipes (9) back to
the
19 combustion chamber (A).
When the inner tanks (2) are under the vacuum condition, the air inlet ends of
21 the cooling three-way valves (Vc 1. . . Vcn) are opened so as to allow the
cold air
22 flowing into the heat insulation tank ( 1 ) and the heating tubes (25) to
purge air from
23 combustion chamber (A) via the exhaust pipe (8) to the air pollution
controlling
24 equipment (F). At the same time, the cold air also cools the inner tanks
(2). When the
temperatures of the inner tanks (2) reach safe values, the pressure releasing
valves
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1 (Vi 1. . . Vin) are gradually opened to allow the pressures inside the inner
tanks (2) to
2 return to the atmosphere pressure. Then, the air inlet ends of the cooling
three-way
3 valves (Vc 1. . . Vcn) and the pressure releasing valves (Vi 1. . . Vin) are
closed.
4 Hereafter, the top covers (3) are enabled to be detached and the inner tanks
(2) are
taken out from the cracking troughs (A 1. . . An). Residuum of the waste tires
inside the
6 inner tanks (2) after cracking is then poured out from the inner tanks (2)
and new
7 batch of the waste tires pieces is loaded into the inner tanks (2) to repeat
the
8 aforementioned operational procedures.
9 When the operational procedures are completed in one of the cracking
troughs (A 1 ), the cooling three-way valves (Vc 1. . . Vcn), pressure relief
valves
11 (Vi 1. . . Vin), and ends of the three-way recycle valves (Vs 1. . . Vsn)
to the cold air are
12 opened accordingly so as to lower the pressure and the temperature of the
heat
13 insulation tanks ( 1 ) until they reach suitable values. Each cracking
trough (A 1 ) is
14 operated independently to remove the residuum of the waste tires, and
therefore the
operational procedure of other cracking troughs (Al ...An) is not interrupted.
Hence,
16 the cracking processes of the waste tires are operated continuously. This
is a fast and
17 efficient process that also requires less manpower than prior arts.
Additionally, the
18 residual solids of the waste tires after thermal cracking are carbon black
and steel
19 wires, which can be recycled.
Also, the heating tubes (25) in each inner tank (2) of each cracking trough
(A)
21 have multiple heat heating plates (251) installed on the outer periphery
thereof so as
22 to improve the effect of heat transfer and enhance the efficiency of heat
recovery and
23 reduce heat loss.
24 Additionally, the top covers (3) of all cracking troughs (A1...An) are
equipped with the discharge pipes (7), heat exchanger (B), and vacuum pump (E)
so
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that the residual cracking gases from the waste tires are completely evacuated
before
2 releasing pressures and the opening the top covers (3). Therefore, residual
cracking
gases in the inner tanks (2) are removed to prevent polluting the environment
and
4 endangering health of operators.
Even though numerous characteristics and advantages of the present
6 invention have been set forth in the foregoing description, together with
details of the
7 structure and function of the invention, the disclosure is illustrative
only, and changes
may be made in detail, especially in matters of shape, size, and arrangement
of parts
9 within the principles of the invention to the full extent indicated by the
broad general
meaning of the terms in which the appended claims are expressed.
