Akinori
ITO
Plastic-to-Oil Conversion
Plastic to
Oil Fantastic
by Carol Smith

We are all well aware of plastic’s “rap-sheet.” It has
been found guilty on many counts, including the way its
production and disposal raises resource issues and lets loose
extremely negative environmental impacts.
Typically made from petroleum, it is estimated that 7% of the
world’s annual oil production is used to produce and
manufacture plastic. That is more than the oil consumed by the
entire African continent.
Plastic’s carbon footprint includes landfilling and
incineration, since sadly, its recycle rate is dismally low
around the globe.
Plastic trash is also polluting our oceans and washing up on
beaches around the world. Tons of plastic from the US and
Japan are floating in the Pacific Ocean, killing mammals and
birds. Perhaps this tragedy is best captured in the TED
presentation by Capt. Charles Moore of the Algalita Marine
Research Foundation.
Using less, or use it better?
Thankfully, there are those who fully appreciate that plastic
has a higher energy value than anything else commonly found in
the waste stream. A Japanese company called Blest created a
small, very safe and easy to use machine that can convert
several types of plastic back into oil.
"If we burn the plastic, we generate toxins and a large amount
of CO2. If we convert it into oil, we save CO2 and at the same
time increase people’s awareness about the value of plastic
garbage. " — Akinori Ito, CEO of Blest.
Though Japan has much improved its “effective utilization”
rate over the years to 72% in 2006, that leaves 28% of plastic
to be buried in landfills or burned. According to Plastic
Waste Management Institute data, “effective utilization”
includes not just the 20% that is actually recycled, but also
52% that is being incinerated for “energy recovery” purposes,
i.e., generating heat or electric power.
“If we burn the plastic, we generate toxins and a large amount
of CO2. If we convert it into oil, we save CO2 and at the same
time increase people’s awareness about the value of plastic
garbage,” says Akinori Ito, CEO of Blest.
Blest’s conversion technology is very safe because it uses a
temperature controlling electric heater rather than flame. The
machines are able to process polyethylene, polystyrene and
polypropylene (numbers 2-4) but not PET bottles (number 1).
The result is a crude gas that can fuel things like generators
or stoves and, when refined, can even be pumped into a car, a
boat or motorbike. One kilogram of plastic produces almost one
liter of oil. To convert that amount takes about 1 kilowatt of
electricity, which is approximately ¥20 or 20 cents’ worth.
The company makes the machines in various sizes and has 60 in
place at farms, fisheries and small factories in Japan and
several abroad.
“To make a machine that anyone can use is my dream,” Ito says.
“The home is the oil field of the future.”
Perhaps that statement is not as crazy as it sounds, since the
makeup of Japanese household waste has been found to contain
over 30 % plastic, most of it from packaging.
Breakdown of plastic waste in the average Japanese household
Sources: Kohei Watanabe, Reference material provided for the
talk
“Waste and Sustainable Consumption”, Capability and
Sustainability Centre,
St Edmund’s College Cambridge, March 2005; Association of
Regional Planners
and Architects, Detailed Sorting and Measuring of Household
Waste, Kyoto 1998.
Continually honing their technology, the company is now able
to sell the machines for less than before, and Ito hopes to
achieve a product “that any one can buy.” Currently the
smallest version, shown in the videobrief, costs ¥950,000 (US
$9,500).
Changing how we think
But it is the educational application of the small model of
the machine that Ito is most passionate about. He’s taken it
on planes on many occasions as part of a project that began
some years ago in the Marshall Islands. There he worked with
local government and schools to teach people about recycling
culture and the value of discarded plastic, spreading the
Japanese concept of mottainai, the idea that waste is sad and
regrettable.
In such remote places, the machine also serves as a practical
solution to the plastic problem, much of it left behind by
tourists: the oil produced is used for tour buses or boats,
Ito says.
Plastic’s carbon footprint includes landfilling and
incineration, since sadly, its recycle rate is dismally low
around the globe.
“Teaching this at schools is the most important work that I
do,” Ito reflects. In Japan too, he visits schools where he
shows children, teachers and parents how to convert the
packaging and drinking straws leftover from lunch.
If we were to use only the world’s plastic waste rather than
oil from oil fields, CO2 emissions could be slashed
dramatically, he says.
“It’s a waste isn’t it?” Ito asks. “This plastic is every
where in the world, and everyone throws it away.”
A mountain to climb down
The wonderful invention of plastics has spawned a huge problem
that we are struggling to solve. With peak oil looming, things
are set to change, but we find ourselves on top of an oil and
plastic mountain, and the only way forward is down.
So while many solutions like this are not without hiccups or
detractors, they are a step forward in coming to terms with
our oil and plastics dependence and help raise awareness of
the carbon footprint of its production and use. Somehow we all
know that plastics is a habit we need to kick. But that
doesn’t seem to make it any easier.
Perhaps the best thing you can do is to look more deeply into
this issue. A good place to start is the 2008 Addicted to
Plastic documentary from Cryptic Moth productions. You can
watch the trailer online and maybe request it at your local
video rental store.
According to the blurb, “the film details plastic’s path over
the last 100 years and provides a wealth of expert interviews
on practical and cutting edge solutions to recycling, toxicity
and biodegradability.”
Next it is just a matter of taking action to break our love
affair with plastic.
USP
Appln 2009117015
KR20090031685
LIQUEFYING APPARATUS
Inventor: SHIMO YOSHIKO [JP] ; ITO AKINORI
Abstract -- A liquefying
apparatus capable of efficient disposal of plastics. There is
provided a liquefying apparatus comprising melting section (1)
for heating charged plastic so as to melt the same and
cracking section (2) for further heating the plastic melted in
the melting section (1) so as to attain gasification cracking
thereof, wherein the cracking section (2) slants upward and in
its interior is fitted with lead screw (LS), the upper end
portion thereof equipped with upward directed catalyst tube
(19) and with downward directed residue takeoff section (R),
and wherein the cracking section (2) is furnished with means
for preventing descending of any plastic melt gas through the
residue takeoff section
Description
FIELD OF THE INVENTION
[0001] The present invention, relates to an apparatus for
converting plastic back to oil.
DESCRIPTION OF THE RELATED ART
[0002] In recent years, along with rapid increase in global
population and economic growth in many countries,
environmental problems have been discussed as issues of global
scale, the problems being, for example, insufficiency of
natural resources for a rapidly increasing energy demand,
global warming due to large consumption of fossil fuels, and
disposal of garbage, scraps and various consumed products.
[0003] Therefore, recycling technologies are becoming much
more important among the technologies for effectively
utilizing the resources.
[0004] In the recycling technologies, there is known a
small-sized apparatus for obtaining oil from waste plastic,
for example, the apparatus comprising a hopper, a cylindrical
melting unit having a lead screw mounted therein, a
cylindrical decomposing unit for vaporization-decomposing
plastic melted by the melting unit, and heaters wound around
the melting unit and the decomposing unit, wherein the plastic
is heated by the heater and vaporized, and the vaporized
plastic gas is made to pass through a catalyst and cooled in a
condenser to be liquefied, and the resultant liquid is taken
out as oil, while residue is collected in a residue takeout
unit (Patent Document 1).
DISCLOSURE OF THE INVENTION
Problem to be Solved by the
Invention
[0005] However, in order to efficiently treat a large quantity
of and variously mixed plastics and to practically operate the
apparatus for converting plastic to oil, such conventional
apparatus needs more to be improved.
[0006] The present invention is pursued to solve such problem
and an object of the present invention is to provide an
apparatus for conversion-to-oil capable of efficiently
treating plastic.
Means for Solving the Problem
[0007] The apparatus for conversion-to-oil according to the
present invention comprises a melting unit for melting plastic
by heating, and a decomposing unit for vaporizing and
decomposing the molten plastic melted by the melting unit by
further heating. The decomposing unit is inclined upward,
having a lead screw therein and provided on its upper end
portion with a catalyst cylinder directing upward and a
residue takeout unit directing downward. The decomposing unit
has a prevention means for preventing the molten plastic gas
from flowing down to the residue takeout unit.
[0008] In an aspect, the prevention means for preventing the
molten plastic gas from flowing down may be an open/close
valve located at a takeout port of the residue takeout unit
for taking out the residue. Further, close to the open/close
valve may be arranged a heater for heating the inside of the
residue takeout unit.
[0009] In another aspect, the prevention means for preventing
the molten plastic gas from flowing down may be a suction unit
located at a gas takeout port of the catalyst cylinder for
taking out the molten plastic gas and for sucking the molten
plastic gas.
[0010] In the other aspect, the prevention means for
preventing the molten plastic gas from flowing down may be a
cylinder valve, which connects to the lower side of the
decomposing unit and has a spiral member rotatable so as to
extrude the residue.
[0011] In the catalyst cylinder of the conversion-to-oil
apparatus of the invention may be contained synthesis zeolite
composed of silicon oxide and alumina.
[0012] Further, the conversion-to-oil apparatus of the
invention may have a residue pot for collecting and heating
the residue, located close to the end portion of the
decomposing unit, the residue pot having an open/close lid.
[0013] Furthermore, the melting unit of the conversion-to-oil
apparatus of the invention may be constructed to melt the
plastic fed from the hopper by frictional heating due to the
rotation of the screw in its cylinder and a heat applied from
the heater.
[0014] In another aspect of this invention, the
conversion-to-oil apparatus may comprise a melting unit for
melting and feeding crushed plastic, and a decomposing unit
for decomposing and vaporizing the molten plastic melted by
the melting unit, wherein the melting unit and the decomposing
unit have, respectively, lead screws rotated by motors, and
the melting unit and the decomposing unit are respectively
heated by heaters. The conversion-to-oil apparatus has a
diesel-powered generator driven by bubbling-treated oil, which
is obtained by subjecting the oil produced by the
conversion-to-oil apparatus to bubbling treatment for removing
gasoline content. By the power from this generator operate the
electric driven units such as the heaters and motors.
[0015] In still another aspect of this invention, the
conversion-to-oil apparatus may comprise a melting unit for
melting and feeding crushed plastic, and a decomposing unit
for decomposing and vaporizing the molten plastic melted by
the melting unit, wherein the melting unit and the decomposing
unit have, respectively, lead screws rotated by motors, and
the melting unit and the decomposing unit are respectively
heated by heaters. The conversion-to-oil apparatus has a
diesel-powered generator driven by blended oil, which is
obtained by blending the oil produced by the conversion-to-oil
apparatus with food oil.
[0016] In the other aspect of this invention, the
conversion-to-oil apparatus may comprise a melting unit for
melting and feeding crushed plastic, and a decomposing unit
for decomposing and vaporizing the molten plastic melted by
the melting unit, wherein the melting unit and the decomposing
unit, respectively, have lead screws rotated by motors, and
the melting unit and the decomposing unit are respectively
heated by heaters. In this conversion-to-oil apparatus, the
generator is powered by an off-gas generated during the
liquefaction of plastic and the oil produced by the
conversion-to-oil apparatus. This produced oil is the
bubbling-treated oil, of which gasoline content is removed by
bubbling treatment.
[0017] In the other aspect of this invention, the
conversion-to-oil apparatus may comprise a melting unit for
melting and feeding crushed plastic, and a decomposing unit
for decomposing and vaporizing the molten plastic melted by
the melting unit, wherein the melting unit and the decomposing
unit, respectively, have lead screws rotated by motors, and
the melting unit and the decomposing unit are respectively
heated by heaters. The conversion-to-oil apparatus has a
diesel-powered generator driven by off gas generated during
the liquefaction of plastic and the oil produced by the
conversion-to-oil apparatus. The produced oil is blended with
food oil.
Effect of the Invention
[0018] According to the present invention, since a prevention
means (fan for pressure control, valves of residue takeout
unit, etc.) for preventing the vaporized gas from coming into
the residue takeout unit and being liquefied to cause
non-decomposed oil is provided around the catalyst cylinder of
the decomposing unit, such non-decomposed oil could not be
stored in the residue tank and thus plastic can be efficiently
treated.
[0019] Further, the conversion-to-oil apparatus of the
invention has a diesel-powered generator, and in the case of
using the bubbling-treated oil obtained by removing gasoline
content from the produced oil or the blended oil obtained by
blending the produced oil with food oil, the generator can be
smoothly and efficiently operated and therefore plastic can be
efficiently treated.
[0020] Furthermore, if a dual fuel engine is employed for the
generator, it is possible to make good use of off-gas as an
energy. Thus plastic can be efficiently treated.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective
view showing a conversion-to-oil apparatus of the present
invention as a whole;
FIG. 2 is an exploded view
showing an inner structure of the upper portion;
FIG. 3 is a diagram for
chaining an electrical generating system;
FIG. 4 is a diagram
roughly showing a system of a dual fuel engine;
FIG. 5 is a perspective
view showing a mixing unit of the dual fuel engine;
FIG. 6 is a view
explaining the structure of a water-in tank;
FIG. 7 is a system
flowchart of the dual fuel engine;
FIG. 8 is a diagram for
explaining another embodiment of a gel-forming unit;
FIG. 9 is a view roughly
showing the structure of the present invention;
FIG. 10 is a view showing
the end portions of a melting unit and a decomposing unit;
FIG. 11 is a block diagram
showing a pipe arrangement for vaporized gas;
FIG. 12 is a view for
explaining a fluid level meter for molten plastic;

FIG. 13
is a view for explaining an attached condition of a
thermometer;
FIG. 14 is a view for
explaining the function of a condenser; and
FIG. 15 is a view showing
the upper part of a vaporizing unit
EXPLANATION OF REFERENCE NUMERALS
[0000]
1: gel forming unit (melting unit)
2: decomposing unit
7: hopper
8: cylinder
11: screw
17: cylinder valve
18: residue pipe
19: catalyst cylinder
23: suction unit
28: oil tank
30: filter
50: bubbling unit
51: blending vessel
53: food oil tank
58: controller
60: generator
110: dual fuel engine
301: hopper
302: first melting unit
303: second melting unit
304: vaporizing unit
313: catalyst cylinder
314: residue pipe
317: first condenser
318: second condenser
PREFERRED EMBODIMENTS FOR
CARRYING OUT THE INVENTION
[0061] Hereafter, embodiments of the present invention will be
described in detail with reference to the drawings.
First Embodiment
[0062] In FIG. 1, a conversion-to-oil apparatus M1 according
to a first embodiment of the present invention comprises a
gel-forming unit 1 for melting crushed plastic pieces into
plastic gel, and a decomposing unit 2 for thermally
decomposing the plastic gel melted by the gel-forming unit 1.
The gel-forming unit 1 is provided with a feeding unit 3 for
feeding the crushed plastic pieces to a hopper 7. The feeding
unit 3 has a feeding pipe 4, in which a known spiral member
(not-shown) is mounted. By rotation of the spiral member, the
plastic is continuously fed to the hopper 7. The feeding unit
3 has a hanging member 6 held by a holding hook 5.
[0063] The hopper 7 is fixed to a frame body 9, and a cylinder
8 extends horizontally from the frame body 9. In the cylinder
8 is mounted a screw 11, which rotates in a space hole 12, and
a vertical hole 13 extends downward from the end of the space
hole 12.
[0064] The screw 11 rotates by means of a motor 10 mounted to
the frame body 9. A wall of the space hole 12 is heated an
electrical heater (not shown) installed in the cylinder 8.
[0065] The gel-forming unit 1 melts the plastic pieces fed
from the hopper 7 by frictional heating due to the rotation of
the screw 11 in the cylinder 8 and the heat applied by the
heater not shown, thus forming the plastic gel. Specifically,
the plastic pieces in the hopper 7 are continuously fed into
the cylinder 8 and fed through in the space hole by the
rotation of the screw 11 and at the same time the plastic
pieces are being melted into plastic gel by the frictional
heating due to the feeding force of the screw 11 and the heat
from the heater not shown. Thus, by using the forcible feeding
action of the screw, the problem that the cylinder 8 is liable
to be clogged by some kind of plastic, PET for example, having
an increasing moisture content and a high melting point, and
the viscosity of which increases as the plastic pieces are
melted solely by the heat from the heater can be solved. Here,
as the forcible feeding means may be employed a means such as
used in the extrusion forming method and the injection forming
method for forming plastic.
[0066] The decomposing unit 2 is inclined upward and has a
lead screw LS (FIG. 2) in it. Namely, the bottom end of the
vertical hole 13 is connected to the lower portion of the
cylindrical decomposing unit 2, in which the lead screw LS is
mounted. The lead screw LS is comprised of a shaft 15 and
blades 15a disposed around the shaft 15. By the lead screw LS,
the plastic gel and the vaporized plastic gas (vaporized gas
or molten plastic gas) are guided in a spiral fashion. The
upper end of the lead screw LS is connected to a motor 14.
Around the cylindrical body of the decomposing unit 2 are
mounted belt-like heaters 16, 16 . . . 16 at a predetermined
intervals, the heaters 16 being covered with heat insulator
(not shown).
[0067] At the upper end portion of the decomposing unit 2 is
provided a residue takeout unit directed downward. Concretely,
as shown in FIG. 2, the residue takeout unit R is located at
the lower side of the upper portion of the cylindrical body of
the decomposing unit 2. The residue takeout unit R has a
cylindrical valve 17 connected to the lower side surface of
the cylindrical body of the decomposing unit. The cylindrical
valve 17 is one of the prevention means for preventing the
molten plastic gas from flowing down to the residue takeout
unit R.
[0068] The cylindrical valve 17 has a spiral member, which
rotates to extrude the residue. Concretely, in the cylindrical
valve (spiral valve) 17 is mounted a spiral member 42, which
rotates slowly by a motor 40 so as to prevent the vaporized
gas from directly coming into a residue pipe 18. By this
prevention for the vaporized gas from directly coming into the
residue pipe 18, the vaporized gas and the residue can be
reliably separated from each other to thereby enhance the
efficiency of recovering oil.
[0069] In addition, downwardly from the lower side of the
upper portion of the cylindrical valve 17 extends the residue
pipe 18, in which an open/close valve 41 is mounted. The
open/close valve 41 is closed to completely shut off the gas
flowing to a residue tank, while the open/close valve 41 is
periodically opened so as to discharge the residue. The
open/close valve 41 is also one of the prevention means for
preventing the molten plastic gas from flowing down to the
residue takeout unit R. Namely, the open/close valve 41
serving as the prevention means for preventing the molten
plastic gas from flowing down is located to be opened and
closed at the residue takeout port of the residue takeout unit
R, and adjacent to the open/close valve 41 is arranged a
heater 70 for heating the inside of the residue takeout unit
R.
[0070] Further, around the cylinder including the spiral
member 42 and the pipe including the open/close valve 41 are
arranged heaters 70, 70 . . . 70 for heating the vaporized gas
existing above the cylindrical valve 17 and the open/close
valve 41, the heaters serving to prevent the vaporized gas
from being liquefied. In particular, the heater 70 around the
pipe including the open/close valve 41 protects the function
of the open/close valve 41 from being degraded, because the
function of the open/close valve would be damaged if the
residue is cooled to be a solid block (the open/close valve 41
would be no longer closed due to such block of the residue,
with the result that the vaporized gas would flow into the
residue takeout unit R, for instance). With the open/close
valve 41 effectively operated, the vaporized gas and the
residue can be reliably separated from each other so that the
efficiency of recovering oil is improved. In addition, with
the arrangement of the heaters 70 substantially from the
connecting portion between the cylindrical valve 17 and the
residue pipe 18 to the open/close valve 41, the open/close
valve 41 can be much more efficiently operated.
[0071] Furthermore, a means for introducing nitrogen 71 from
the upper end of the residue pipe 18 may be employed for
preventing the vaporized gas from flowing-down. This is also
one of the prevention means for preventing the molten plastic
gas from flowing down to the residue takeout unit R. Namely,
this means serves to prevent the flow-down of the gas
vaporized from the decomposing unit 2 to the residue takeout
unit R by way of increasing the pressure on the side of the
residue takeout unit R.
[0072] At the upper end portion of the decomposing unit 2 is
provided a catalyst cylinder 19 extending in the upward
direction. Specifically, at a position downwardly apart from
the cylinder valve 17 is located the catalyst cylinder 19, in
which a catalyst composed of zeolite 44 is contained via a
detachable cage C. Around the outer periphery of die catalyst
cylinder 19 are attached a heater 45 for thermal control and a
water-cooling jacket 46, by which the catalyst in the cylinder
19 is thermally controlled. The catalyst cylinder 19 has an
upper flange detachably mounted by a flange of an enlarged
portion of a guide pipe 22 and a clamp 20. By this
configuration, the cage C for the catalyst is detachable so
that the catalyst can be changed after having been used for a
predetermined time. The catalyst may be of synthesis zeolite
preferably having an effective fine diameter of 9 to 10 mm and
having a ratio of 2.5 times SiO2 to Al2O3, and of spherical
piece having a size of 2.4 to 4.7.
[0073] A quantity of the catalyst may correspond to the
quantity of the plastic pieces to be treated. For instance,
nearly 10 kg catalyst is required for treating 10 kg plastic
pieces per hour, that is, substantially the quantity of the
plastic pieces to be treated and that of the catalyst
correspond to each other by 1:1 in weight.
[0074] In other words, with a less quantity of the catalyst,
the plastic pieces could not completely be decomposed, causing
non-decomposition oil, while an excessive quantity of the
catalyst would unfavorably cause a flow resistance to
increase.
[0075] At the guide pipe 22 serving as a molten plastic gas
takeout portion of the catalyst cylinder 19 is provided a
suction unit 23 having a fan 43, by which the vaporized gas is
sucked to cause a negative pressure so that the vaporized gas
can smoothly pass through the catalyst cylinder without
flowing into the residue pipe 18. Thus, this unit is also one
of the prevention means for preventing the molten plastic gas
from flowing down to the residue unit R. In addition, as the
prevention means for preventing the molten plastic gas from
flowing down to the residue takeout unit R, two or more of the
above-mentioned prevention means may be selectively combined
to each other. The combination of the plural prevention means
enhances the function of preventing the molten plastic gas
from flowing down to the residue takeout unit R.
[0076] Incidentally, it is required to set a distance L
between the center of a flow inlet of the catalyst cylinder 19
and the center of the port of the cylinder valve 17 at least
35 cm and more. With the distance of 45 cm, the quantity of
the vaporized gas flowing to the residue pipe 18 decreases
remarkably. Without the cylinder valve 17 but the residue pipe
18 is directly connected to the cylindrical body of the
decomposing unit, the center of the port of the residue pipe
corresponds to the center of a spiral valve 17.
[0077] The guide pipe 22 is, as shown in FIG. 1, connected to
a water-cooling condenser 24, which has a water inlet pipe 26
and a discharge pipe 25. From the condenser 24 extends
downwardly an oil pipe 27 and the oil liquefied in the
condenser 24 is stored in an oil tank 28. From the oil tank 28
extend an off-gas pipe 31 for discharging non-liquefied
off-gas and an oil pipe 29 for taking-out collected oil, the
oil pipe 29 having a filter 30.
[0078] Next, a power generation system is described with
reference to FIG. 3.
[0079] The conversion-to-oil apparatus M1 comprising a melting
unit 1 for melting and feeding crushed plastic, and a
decomposing unit 2 for decomposing and vaporizing the molten
plastic melted by the melting unit 1, wherein the melting unit
and the decomposing unit, respectively, have lead screws
rotated by motors 10, 14 and the melting unit and the
decomposing unit are heated by heaters, respectively, further
comprises, as shown in FIG. 3, a diesel-powered generator 60
driven by bubbling-treated oil, which is obtained by
subjecting the oil produced by the conversion-to-oil apparatus
M to bubbling treatment for removing gasoline content. The
electric-driven units such as the heater 62 and the motor 61
operate by the power from this generator.
[0080] In FIG. 3, the oil pipe 29 is connected to a bubbling
unit 50 in addition to the filter 30. The collected oil is
subjected to the bubbling-treatment for removing gasoline
content by the bubbling unit 50. The collected oil contains
the mixture of gasoline, kerosene, light oil, and heavy oil.
As the gasoline (contained in the mixture oil by approximately
10%) tends to wash away the lubricant of the engine, it needs
be removed. Therefore, air is fed to the mixture oil to remove
the gasoline content. The oil treated by the bubbling unit 50
passes through a line 100 and is fed to a line 101. At the
line 101, the bubbling-treated oil has its flow quantity
controlled by a flow control valve 59 and is fed to the
generator 60. By the generator 60 operate the various motors
61 and heaters 62 of the conversion-to-oil apparatus M1.
[0081] Further, the generator 60 may be powered by the blend
oil obtained by blending the oil produced by the conversion-to
oil apparatus M1 with food oil. Concretely, the oil, instead
of passing through the bubbling unit 50, filtrated by the
filter 30 is fed to a blending vessel 51 having a stirrer 52.
Waste food oil, which is composed of plant oil, is fed from a
food oil tank 53 to the blending vessel 51, where the waste
oil and the recovered oil are blended by the ratio of 1:1.
Thus, when the waste oil is added to the recovered oil (in a
proportion of 10% or more), action of the gasoline content is
suppressed so that the blended oil even including the gasoline
content becomes usable oil.
[0082] Furthermore, the generator 60 may be powered by both
the off-gas generated during the liquefaction-to-oil of
plastic and the product oil of the conversion-to-oil apparatus
M1. Concretely, the generator 60 may operate solely by the
blended oil, and if the generator 60 employs a dual-fuel
engine as the diesel engine, both the blended oil and the
off-gas become usable. Specifically, the gas, including the
mixture of methane, ethane, propane and others, passes through
the off-gas pipe 31 to a water-in tank 54. After passing
through the water-in tank 54, the off-gas is stored in an
accumulation tank 55, then passes through a flow control valve
57, which is controlled by a controller 58 (the flow control
valve 59 is also controlled by the controller 58), and flows
into the generator 60. The controller (CPU) 58 effectively
prevents engine knocking by appropriately controlling the
respective quantities of the blended oil and the off-gas for
the engine of the generator.
[0083] Next, a controller system for the dual-fuel engine of
the generator 60 is described in detail with reference to
FIGS. 4 to 7.
[0084] In FIG. 4, a dual-fuel engine 110 has a piston 111, and
has a flow-in valve 112 and a discharge valve 113. Between
both valves is provided an injection nozzle 114, to which the
blended oil (i.e., the oil having been blended with the
bubbling-treated oil or food oil) is supplied from an
injection pump 115. A flow-in pipe 116 connected to the
flow-in valve 112 is provided with a mixed gas control valve
117, which controls a quantity of the mixed gas flowed into
the engine from a mixing unit 118 for mixing the off-gas with
air. The mixing unit 118 is connected to a gas control valve
119 mounted to the off-gas pipe 102, and the control valves
117, 119 and the injection pump 115 are connected to the
controller (CPU) 58. The mixing unit 118 has a cylindrical
casing 118a, as shown in FIG. 5, in which an air filter 120 is
mounted. The air passing through an inlet 121 is guided by
guide blades 122 to pass through a filter unit 23 and flow to
the cylinder. On the other hand, the off-gas passes through
the off-gas pipe 102 and is supplied from an injection pipe
120a, which is circularly formed around an opening of the
right end of the air filter 120 and injects the off-gas in a
circular fashion. By this way, the off-gas and air is suitably
mixed. Incidentally, the guide blades 122 rotate by the air
supplied from the inlet 121 to thereby rotate the air filter.
By this rotation, the off-gas from the off-gas pipe 102 and
the air from the inlet 121 are uniformly mixed, thereby
increasing combustion efficiency.
[0085] The water-in tank 54 in FIG. 3 has a rectangular
cylindrical casing 130, which is partitioned into two rooms by
a partition plate 131. The lower edge of the partition plate
31 is positioned at a given height up from the bottom of the
casing 130 (FIG. 6).
[0086] The left room R1 partitioned by the partition plate 131
is provided with an atmosphere pipe 132 open to the
atmosphere, and the lower end of the atmosphere pipe 132 is
positioned lower than that of the partition plate 131. The
left room R1 accommodates an end portion of the off-gas pipe
31 extending from the oil tank 28, and the end portion of the
off-gas pipe 31 extends close to the bottom of the casing 130
and to a position lower than that of the lower end of the
atmosphere pipe 132. The right room R2 partitioned by the
partition plate 131 accepts an end portion of the line 102 and
is connected to the accumulation tank 55. In the water-in tank
54, water is stored up to a level higher than the lower edge
of the partition plate 131 to form a base level B.L. Now, when
the pressure in the right room R2 decreases (when the engine
takes in a large quantity of off-gas), the pressure of the
right room R2 is lowered than that of the left room R1 so that
the water level in the left room R1 is lowered to a position
134, which is lower than the base level B.L, and the water
level in the light room R2 rises up to an upper position 133.
Accordingly, the pressure of the left room R1 decreases so
that the off-gas goes out more easily from the off-gas pipe
134, while the off-gas is supplied to the right room R2 to
thereby increase the pressure of the right room R2 so that the
water level in the right room R2 is lowered and the water
level in the left room R1 rises. Then, if the respective
pressures in both rooms increase extraordinarily higher than
the atmospheric pressure, water is discharged outside through
the atmosphere pipe 132. Namely, it is possible to determine a
supply quantity and a consumption quantity of the off-gas by
detecting the position of either one of the water levels in
the right room R2 and the left room R1 by means of a level
meter. Thus detected signals are fed to the controller (FIGS.
3, 4) mentioned above, and correspondingly the off-gas
quantity to be supplied to the dual-fuel engine is adjusted.
[0087] As shown in FIG. 7, the off-gas line 102 is provided
with an on/off safety valve 150 and a flow control valve 151.
The line 102 terminates at a compressor 154, the compressor
154 being operated by the power of the generator 60. The
off-gas compressed by the compressor 154 passes through a flow
control valve 153 and flows into the accumulation tank 155. In
the accumulation tank 155 is stored water and in an upper
space 160 above the water surface is stored the off-gas. When
the upper space 160 becomes larger (when a larger quantity of
the off-gas is compressively stored), the water in the
accumulation tank 155 comes into a water tank 161, which is
connected to a relief valve 162 through a pipe 163. Before the
flow control valve 153 is provided a line 164, on which a
pressure control valve 152 for the off-gas is mounted. If the
pressure of the compressed off-gas fed from the compressor 154
exceeds a predetermined value, part of the off-gas passes
through the valve 152 and returns to the line 102, where the
returning off-gas joins fresh off-gas flowing through the line
102 and comes in the compressor 154 again.
[0088] The compressed off-gas fed from the accumulation tank
155 passes through a maximum flow control valve 156 and the
control valve 119 mentioned before, which opens or closes,
depending on a load applied to the engine 110 (FIG. 4) of the
generator 60, comes in the mixing unit 118, where the off-gas
is mixed with air, and the mixed gas flows into the engine
110. Then, the controller 58 controls, as shown in FIG. 4, the
control valve 119, the mixed gas control valve 117, and the
fuel injection pump 115 to thereby adjust the respective
quantities of the mixed gas and the liquid fuel (blend oil) to
be supplied. According to experiments, it turned out that when
the proportion of the mixed gas to the liquid fuel is within 7
to 3, the engine operates normally but if the proportion of
the mixed gas exceeds the above range, they become out of
balance, causing engine-knocking. In practical operation of
the dual-fuel engine, at first the liquid fuel is fed for
initial rotation of 1500 rpm as a standard control pattern and
subsequently the off-gas is fed to the engine so that the
quantity of the liquid fuel injected by the fuel injection
pump 115 is reduced under the control of the controller CPU 58
to thereby throttle down the engine.
[0089] The gel-forming unit may preferably be formed in a
vertically long configuration as shown in FIG. 8 so that the
apparatus can be constructed in a compact size as a whole.
[0090] Specifically, a motor 201 is mounted on a frame 202 and
a cylinder 203 is disposed vertically. Plastic pieces are
obliquely fed from a hopper 204 to a space hole 205 of the
cylinder 203 and melted. Here, the tip end of a screw 206 in
the space hole 205 is tapered to form a tapered portion.
[0091] The present invention is most preferably applied to the
liquefaction of waste plastic, especially polypropylene,
polyethylene, and polystyrene by using the thermal
decomposition method. Namely, the waste plastic as industrial
waste disposals can be effectively utilized, and the off-gas
generated in the present apparatus can be used as part of the
power source for the generator, and in particular, in the case
that the off-gas is used for the dual-fuel engine, the
liquefied product oil and the off-gas can be utilized to the
fullest.
[0092] In the conventional apparatus for conversion-to-oil, if
too much quantity of plastic pieces is fed, or a large
quantity of PE (polyethylene) with a large melting energy is
fed to the decomposing unit from the hopper, the rotation of
the lead screw is obstructed by the viscosity of the molten
plastic during the melting process unfavorably, which is
so-called clogging phenomenon. On the other hand, in the
embodiment of the present invention, the melting unit is
constructed like an injection molding machine to melt plastic
pieces into plastic gel by frictional heating and heat from
heaters and feed the plastic gel to the decomposing unit.
Thus, the variously mixed plastic pieces can be surely melted
without clogging the melting unit and the clogging phenomenon
can be prevented and plastic can be efficiently treated.
[0093] Further, in the case that the catalyst cylinder for
treating PE is employed, the vaporized gas does not always
pass through the catalyst cylinder of the decomposing unit but
partially comes in the residue takeout unit, which could be
cooled without being completely decomposed. The thus
non-decomposed oil, which has been liquefied without passing
through the catalyst cylinder, would be stored in the residue
tank. On the other hand, the present embodiment is provided
around the catalyst cylinder of the decomposing unit with
prevention means (fan for pressure control, valves of the
residue takeout unit, etc.) for preventing the vaporized gas
from coming into the residue takeout unit and being liquefied
into non-decomposed oil. Namely, since the non-decomposed oil
is prevented from being stored in the residue tank, plastic
can be treated much more efficiently.
[0094] Furthermore, in the conventional conversion-to-oil
apparatus, the recovered product oil is usually mixed oil
including gasoline content, kerosene content, light oil
content, and heavy oil content, which may be no problem when
such mixed oil is filtrated to be burned in a waste oil
boiler. However, when such mixed oil is used for driving the
diesel engine, the gasoline content tends to cause a burning
problem or wash away the lubricant of the engine, resulting in
burning-out of the engine. On the other hand, the
conversion-to-oil apparatus of the present embodiment is
provided with a diesel-powered generator, which uses the oil
obtained by subjecting the produced oil to the bubbling
treatment for removing gasoline content or blend oil obtained
by blending the produced oil with food oil. Thus, the
generator can operate smoothly and efficiently and therefore
plastic can be efficiently treated. Still furthermore, when a
dual-fuel engine is employed for the generator, off-gas can be
utilized as an effective energy and plastic can be treated
much more efficiently.
Second Embodiment
[0095] Next, a second embodiment of the present invention is
described with reference to the drawings.
[0096] In FIG. 9, a conversion-to-oil apparatus M2 according
to the second embodiment comprises a hopper 301, to which
crushed plastic pieces are fed, the hopper 301 being mounted
to an end portion of a first melting unit 302 for melting the
plastic pieces, the other end portion of the first melting
unit 302 being connected to an end portion of a second melting
unit 303, which extends perpendicularly to the first melting
unit 302, the other end portion of the second melting unit
being connected to a lower end portion of a vaporizing unit
304 for vaporizing the melted plastic, the vaporizing unit
extending in a slant direction. Each of the first and second
melting units 302, 303 and the vaporizing unit 304 has a
cylindrical body, in which a lead screw is mounted. The
plastic is continuously fed by the rotations of the lead
screws. Around the cylinders are wound belt-like heaters h, h
. . . h, by which respectively the plastic, the molten plastic
liquid, and the vaporized plastic gas in the cylinders are
heated. The belt-like heaters h, h . . . h and the cylindrical
bodies of the first and second melting units 302, 303 and the
vaporizing unit 304 are covered with thermal insulation
members i, respectively. At the ends of the cylindrical bodies
are mounted motors m, m, m, respectively, which are connected
to the lead screws to rotate each at a predetermined speed.
[0097] At a first connecting portion between the first melting
unit 302 and the second melting unit 303 is provided a
vertical connection pipe 305, and at a second connecting
portion between the second melting unit and the vaporizing
unit 304 is provided another vertical connection pipe 306.
Through the connection pipes 305, 306, nitrogen 307, 308 is
introduced into each of the cylinders for assuring safety (for
preventing the vaporized gas from burning). Under the hopper
301 is located a feeding pipe 310, to which a rotary valve 309
for feeding the plastic in the hopper 301 to the first melting
unit 302 for every predetermined quantity is mounted.
[0098] The cylindrical body of the melting unit has its
portion adjacent to the feeding pipe 310 provided with a
cooling jacket so that the plastic is not melted near the
hopper. Nitrogen 312 is also fed to the feeding pipe 310.
[0099] Adjacent to an end portion of the vaporizing unit 304
of the conversion-to-oil apparatus M2 is located a catalyst
cylinder 313 and concretely, as shown in FIG. 9, the catalyst
cylinder 313 extends vertically and upwardly from an upside
end portion of the vaporizing unit 304. In the catalyst
cylinder 313 is stored a catalyst of zeolite. The catalyst may
be of synthesis zeolite preferably having an effective fine
diameter of 9 to 10 mm and having a ratio of 2.5 times SiO2 to
Al2O3, and of spherical piece having a size of 2.4 to 4.7.
This catalyst is able to decompose n-paraffin including C3 or
more and therefore suitable for treating PE.
[0100] At a position more adjacent to the upper end portion of
the vaporizing unit 304 than the connecting position to the
catalyst cylinder 313 extends downwardly a residue pipe 314.
At an intermediate position of the residue pipe 314 is located
a valve 315 as a rotary valve, which discharges a residue to a
residue tank 316 located below the valve 315 while maintaining
the upper space of the residue pipe in a sealed condition.
[0101] Between the first melting unit 302 and the vaporizing
unit 304 are located two condensers 317, 318. Of them, a first
condenser 317 is provided for heavier oil, which compresses
the vaporized gas passing through the catalyst cylinder 313 to
liquefy it and produces heavier oil while cooling the
vaporized gas by air. The other condenser, as a second
condenser 318, compresses the vaporized gas passing through
the first condenser 317 to liquefy it and produces lighter
oil, to which cooling water is supplied. The heavier oil has a
high compression temperature and is therefore sufficient to be
cooled by air and is covered with a thermal insulation
material i.
[0102] The heavy oil produced by the first condenser 317 is
stored in a heavier oil tank 319 and the lighter oil produced
by the second condenser 318 is stored in a lighter oil tank
320.
[0103] In FIG. 10, at bearing portions of the lead screws of
the first and second melting units 302, 303 and the vaporizing
unit (not shown) are provided cover members 330, 331,
respectively. To the cover member 330 and the cover member 331
are connected pipes 332, 333, respectively, both of which 332,
333 are connected to a collecting pipe 304. At an end of the
collecting pipe 334 is mounted a fan 335, by which leaking gas
is discharged outside.
[0104] In FIG. 11, the vaporized gas passing through the
catalyst cylinder 313 is fed through a pipe 340 and comes in
the first condenser 317 to be liquefied to be heavier oil,
which is fed through a pipe 341 and stored in the heavier oil
tank 319.
[0105] Then, the vaporized gas that has not been liquefied by
the first condenser 317 passes through a pipe 342 and comes in
the second condenser 318, while the liquefied lighter oil
passes through a pipe 343 to be stored in the lighter oil tank
320. The off-gas that has not been liquefied by the second
condenser 318 passes through a pipe 395 and comes in both
tanks 319 and 320. The off-gas, coming out of the tanks 319,
320, passes through a pipe 349 and flows into water stored in
a water cylinder 348. The off-gas coming out of the water
passes through an accumulator 350 and a suction pipe 351 and
is supplied to a burner 352 to be burned. The burner 352 heats
a water tank 353 to thereby make hot water. By controlling the
level H of the water in the water cylinder 348, the pressure
of the vaporized gas and the pressure in the liquefaction line
are controlled.
[0106] In FIG. 12, the vaporizing unit 304 is provided with a
liquid level meter Sm for detecting the level S of the
liquefied plastic, the liquid level meter Sm including
nitrogen blow-off ports 360 and 361 arranged distant from each
other, and a controller 362. The level S of the liquefied
plastic can be determined by detecting the blow-off pressure
of nitrogen. According to FIG. 12, since the pressure around
the blow-off port 360 is higher than that around the blow-off
port 361, it is determined that the level S is at an
intermediate position between the blow-off ports 360 and 361.
[0107] As shown in FIG. 13, a thermometer 370 for determining
a temperature in each of the cylinders of the first and second
melting units 302, 303 and the vaporizing unit 304 has a
thermoelectric couple 372 enclosed with a ceramic protection
member 371 penetrated through a cylinder wall w of each of the
cylinders. The thermometer is able to detect the temperature
inside of the cylinder, without detecting the temperature of
the outer wall of the cylinder owing to the protection member
371.
[0108] In FIG. 14, the first condenser 317 is supplied with
air by a fan 381, while at a discharge port 385 for
discharging the air are mounted a thermometer 383 and a flow
meter 384, so that if the fan 381 is controlled based on the
temperature and flow quantity of the discharged air, the
cooling temperature of the first condenser 317 can be
controlled to thereby control the quality of the heavier oil.
[0109] Further, in the melting unit 302 is emitted aqueous
vapor from the plastic being melted, which vapor is fed to the
first condenser 317 through the pipe 380 so as to control the
temperature in the condenser 317. The temperature in the first
condenser 317 may preferably be 200[deg.] C. to 300[deg.] C.,
in which range the liquefaction to heavier oil is suitably
achieved.
[0110] Next, another embodiment of the residue pipe is
described.
[0111] In FIG. 15, adjacent to an end portion of the
vaporizing unit 304 of the conversion-to-oil apparatus M2 is
provided a residue pot 391 for receiving the residue and
heating it. Concretely, the residue pot 391 is located below
at a position obliquely upward from the connecting portion to
the catalyst cylinder 313. At the bottom of the residue pot
391 is provided an open/close lid 393 and around the residue
pot 391 is provided a heater h, by which the vaporized gas
coming in the residue pot is heated and goes up to the
catalyst cylinder 313.
[0112] Even if there remains not-fully vaporized plastic in
the residue, such plastic is finally vaporized in this residue
pot and therefore only the pure residue is left in the residue
pot. After a predetermined quantity of the residue is
accumulated, the open/close lid 393 is opened to feed the
residue to the residue tank 392. On the other hand, the
vaporized gas flowing down to the residue pipe is prevented
from being liquefied in the residue pipe so that the resultant
oil would come in the residue tank. In addition, at an inlet
394 of the residue pot 391 is provided a projecting member
390, by which the residue is prevented from sticking to the
peripheral wall of the residue pot.
[0113] Incidentally, in the hopper 7 of the melting unit 1 of
the first embodiment or the hopper 301 of the first melting
unit 302 of the second embodiment, if the temperature of the
lower end portion of the hopper becomes so high, the plastic
to be fed to the melting unit would be already melted here and
thus melted plastic would be an obstacle to smooth feeding of
the plastic. If necessary, it may be preferable to cool the
periphery of the lower end portion of the hopper 7 or 301 with
a water jacket. Thus, the plastic can be smoothly fed to the
melting unit 1 or 302 by the way of cooling.
[0114] The conversion-to-oil apparatus of the present
invention is particularly used for liquefaction of waste
plastic and suitable for a small-sized conversion-to-oil
apparatus.
[0115] As mentioned above, in the conventional apparatus,
among variously used plastics, PP (polypropylene) and PS
(polystyrene) are ready to be liquefied but the liquefaction
of PE (polyethylene) is difficult and liable to cause a
non-decomposed product like paraffin because of delicate
control of its liquidity. On the other hand, according to the
present invention, since the synthesis zeolite composed of
silicon oxide (SiO2) and alumina (Al2O3) is used, not only PP
(polypropylene) and PS (polystyrene) but also PE
(polyethylene) can be completely decomposed. Thus the present
invention enables efficient liquefaction of plastic.
[0116] Further, as for the case provided with the residue
pipe, it could sometimes occur that after the molten plastic
is vaporized, the vaporized gas comes in the residue pipe for
taking the residue and then the resultant oil coming from the
residue pipe is left in the residue tank. However, the residue
pot of the present embodiment enables the residue, even still
involving the molten plastic, completely to be vaporized,
namely, enables plastic efficiently to be processed.
WO2008004612
APPARATUS FOR CONVERSION
INTO OIL AND PROCESS FOR PRODUCING OIL
Inventor: SHIMO YOSHIKO [JP] ; ITO AKINORI
Abstract -- An apparatus
for efficiently converting foamed styrene resins into an oil.
It can have a smaller size. Also provided is a process for
producing an oil. The apparatus for conversion into oil (M1)
includes a device for conversion into oil (6) which comprises
a gelation unit (72) for converting foamed styrene resins into
a molten gel and a decomposition part (75) for heating the
molten gel to vaporize and decompose it, and which serves to
pyrolyze foamed styrene resins and convert them into an oil. A
volume reduction unit (1) for reducing the volume of foamed
styrene resins has been united to the apparatus for conversion
into oil
JP
2008195821
SMALL-SIZED LIQUEFACTION
EQUIPMENT
Inventor: ITO AKINORI ; ITAGAKI HITOSHI
Abstract -- PROBLEM TO BE
SOLVED: To provide a small-sized liquefaction apparatus
without requiring a special heating device for a catalyst tube
and also without requiring a water-circulating device. ;
SOLUTION: The operation of the small-sized liquefaction
apparatus comprises putting plastics into a melting pot 2,
heating/melting/vaporizing the plastic by a heater 7 wound
around its surroundings, decomposing the evaporated gas by a
catalyst in the catalyst tube 15 a part 15a of which is hanged
in the gas-vaporizing pot, cooling the evaporated gas by a
cooling device 3 having a transparent main body 20 storing
cooling water 23 to float hydrocarbon oil on the cooling water
and recovering the hydrocarbon oil from an oil-recovering tube
24 slightly protruding from the water surface.
JP
2007314654
SYSTEM FOR TREATING STYRENE
FOAM
SHIMO YOSHIKO ; ITO AKINORI
Abstract -- PROBLEM TO BE
SOLVED: To provide a system achieving an efficient plastic
liquefaction utilizing a solvent and to utilize spent lard
being an animal fat for energy. ; SOLUTION: Plastic foams are
disintegrated and dissolved in a solvent in the volume
reduction vessel unit 1. The obtained gel-like mixture is
collected in the vessel 13. The gel-like mixture is thinly
filmed on the heated wall of the solvent separation apparatus
4 to vaporize the solvent. The vaporized solvent is cooled
with a condenser 5 and recovered. The de-solvented gel-like
styrene is poured through the receiving port 100 of a
dissolving section 72 of a liquefaction apparatus 6, vaporized
and decomposed on the slanting decomposition section 75 and
liquified in the condenser 80. The liquid is collected in the
generated oil tank 82. The styrene oil dissolves animal lard
at ordinary temperature. The mixed oil of the lard and the
styrene oil drives the generator.
JP
2007316903
RECYCLE SYSTEM FOR PLASTIC PRODUCT
Inventor: SHIMO YOSHIKO ; ITO AKINORI
Abstract -- PROBLEM TO BE
SOLVED: To provide a recycle system for plastic products,
which efficiently collects useful resources and uses IC cards
to effectively use the resources. ; SOLUTION: The recycle
system 100 for the plastic product 6 has a shop 10 which
collects the plastic product 6 that a user 2 who has the IC
card 5 brings, and an oil center 30 which converts the plastic
product 6 to oil, and reuses the plastic product 6 as oil. The
shop 10 has a collection box 20 which collects the plastic
product 6 that the user 2 throws and an IC card writer 25
which writes a point corresponding to the thrown plastic
product 6 into the IC card 5 when the user throws the plastic
product 6, and reads a point from the IC card 5 when the user
pays for merchandise at the shop 10 to provide a plastic bag
6a to the user 2 based on the point.
JP 2005126454
PLASTIC TREATMENT APPARATUS
Inventor: ITAGAKI HITOSHI
Abstract -- PROBLEM TO BE
SOLVED: To improve the treatment capacity of a plastic
treatment apparatus by increasing the vaporization area of a
liquified molten plastic; and to enable the treatment
apparatus to be conveyed by constructing the whole of the
apparatus compactly and accommodating its main part in a
casing. ; SOLUTION: The apparatus has a drying section 1
having a hopper 7 and an almost horizontally arranged
vaporization section 6 installed below the drying section 1.
In each of the sections 1 and 6, a lead screw 11 is installed.
A crushed plastic and a residue are sent under heating to the
vaporization section 6 to be vaporized, and this vaporized gas
is cooled to give an oil or is directly sent to a boiler or
the like to be used as a fuel.
JP
2004315686
OIL-FORMING PLANT AND WASTE
PLASTIC RECOVERY SYSTEM
Inventor: ITAGAKI HITOSHI
Abstract -- PROBLEM TO BE
SOLVED: To provide an oil-forming plant capable of being
easily designed according to a required treating performance.
; SOLUTION: The oil-forming plant 1 has a decomposition part 3
constituted of a head unit 31, two or more repeating units 32
and a tail unit 33, and forming a decomposed gas by
depolymerizing a plastic by heating, and an oil-forming part 4
for forming an oil by cooling the decomposed gas formed at the
decomposition.
JP
2004269755
LIQUEFACTION PLANT
Inventor: ITAGAKI HITOSHI
Abstract -- PROBLEM TO BE
SOLVED: To provide a liquefaction plant capable of heating
plastics speedily, highly precisely and efficiently. ;
SOLUTION: This liquefaction plant 1 is equipped with a melting
zone 2 wherein plastics are heated and molten, a decomposition
zone 3 wherein the plastics molten in the melting zone 2 are
further heated to cause depolymerization and produce
decomposition gases, and a liquefaction zone 4 wherein the
decomposition gases generated in the decomposition zone 3 are
cooled to produce an oil. The plant is so constructed as to
employ at least an electric heater 42 as a heating means when
heating the plastics in the decomposition zone.
JP
2004175917
OIL-LIQUEFACTION APPARATUS
Inventor: KONNO KUNISUKE ; ITO AKINORI
Abstract -- PROBLEM TO BE
SOLVED: To provide an oil-liquefaction apparatus which
efficiently and quickly can dissolve a crushed plastic, and a
petroleum refining method which can effectively utilize a
collected oil collected by this oil-liquefaction apparatus. ;
SOLUTION: This oil-liquefaction apparatus comprises housing a
previously collected oil in a dissolution tank 1; feeding the
crushed plastic into this collected oil from a plastic feed
device 2; conveying this mixed molten liquid diagonally upward
by a feed screw 6 while heating at the vaporization
temperature; cooling the vaporized gas in a condenser 12 to
collect an oil; returning a part of this oil to the
dissolution tank 1; and further utilizing a part of the
collected oil as a hydrogen source in a petroleum refining
step.