KR101298472B1 - A pyrolysis process and its operation method producing fuel oil from plastic materials - Google Patents

Abstract

The present invention relates to a process for producing a fuel oil for light oil replacement using plastic as a raw material, which is capable of continuous operation by adding a few units to a batch process, and a new process that greatly improves operation rate, thermal efficiency, environment and safety. And a technique characterized by the method of operation thereof.
The general small scale pyrolysis process uses a vertical cylindrical reactor or a rotary kiln type reactor equipped with a stirrer, and it is not possible to promptly input raw materials, and it is inconvenient to discharge residues remaining after the reaction. Therefore, it is operated by repeating the processes leading to input of raw materials, pyrolysis reaction, end treatment, natural cooling of residues and discharge of residues, and the operation time is very long. As a result, the thermal efficiency and productivity is low, the product quality is uneven, and the working environment and stability are poor.
The present invention relates to a novel pyrolysis process consisting of a melt feeder of a raw material, a pyrolysis reactor, a sludge metering feeder, a sludge reactor and a cooling discharge of the residue. It significantly shortens the input time of raw material, which is a problem of the pyrolysis device operated in batch type, and sets a separate reactor for treatment of sludge to enable continuous operation of the main pyrolysis reactor, and naturally cools the residue cooling method of the sludge reactor. Introduced a water jet cooling method to reduce the time required to cool the residue significantly. It is composed so that input of raw materials, melting, pyrolysis reaction, sludge discharge, sludge reaction, and discharge of residues are intermittently performed, and it is configured to automatically measure the amount of transfer from each stage to the next stage without special control device. This is very easy and allows for continuous operation.
This new process is suitable for small-scale plants in line with domestic conditions, and it is expected that the stagnant domestic pyrolysis emulsion market will be activated because of its high throughput, easy operation and excellent economic efficiency compared to the initial investment.

Description

Pyrolysis process and its operation method {A pyrolysis process and its operation method producing fuel oil from plastic materials}

The present invention relates to a process technology for producing fuel oil by pyrolysing plastic, and is a technology characterized by complementing the existing batch pyrolysis process and adopting a new operation method to enable continuous processing.

In Korea, small pyrolysis and emulsification plant technology is preferred because of the small size of the companies and the difficulty of securing large quantities of raw materials. In the case of small plants, most domestic pyrolysis plants adopt a batch process because the economies of scale prevent the introduction of complex continuous processes.

Batch processes are generally composed of reactors, catalyst towers, condensers, oil storage tanks, etc. as main equipment. Most of the reactors are vertical cylinders equipped with a stirrer to heat the lower side and the side, and have a raw material inlet and a residue outlet on the lower side, and an oil vapor outlet on the upper side. In a batch process, a pyrolysis reaction and a terminal treatment for pulverizing the residue are carried out in one reactor.

Most of pyrolysis raw materials are bulk plastics because they are waste plastics. Therefore, the amount that can be added to the reaction of a certain volume is very small, in order to overcome this to repeat the addition and melting, in this case the input time takes much longer than the reaction time.

Feeding and melting of raw materials are repeated (vertical cylindrical) or compressed by attraction (rotary kiln), so the raw material input time is very long or less than the reactor volume. In the present process technology, a melting apparatus is placed in front of the reactor, and a predetermined amount of the raw material is melted using the waste heat of the reactor, and then introduced into the reactor, thereby increasing the volume of the raw material. A very long time is required for one operation because of the cooling and draining operations to take out the residues. When the reactor capacity is 2 tons / time or more, 30 hours or more of operation time is required, so the maximum is 2 tons or less, and in order to expand the plant capacity, it is difficult to construct the same plant in parallel.
These prior arts include Korean Patent No. 10-0140957 (filed on July 28, 1994), Korean Patent No. 10-0140899 (filed on December 4, 1997), and Korean Patent No. 10-1125844 (2009). 12/28).

The existing small scale pyrolysis process consists of a raw material input device, a vertical cylindrical stirred reactor (STR) in the form of a cauldron, a catalyst tower, a pyrolysis gas condenser, a secondary cracking reactor for the oil produced, a storage tank and a residue treatment facility. Raw materials undergo only minimal pretreatment (refining) processes such as crushing and specific gravity to reduce costs. At this time, the selected raw material contains a large amount of impurities such as metal, earth and sand, and moisture, and the volume is very large. Such raw materials cannot be charged with a large amount of raw materials in the reactor, and after the pyrolysis, a large amount of residues remain in the reactor, and thus, raw materials cannot be added anymore, and the raw materials are operated in a batch operation manner after removing them. There are several limitations and problems. In addition, thermal efficiency is very low due to a separate fuel supply required for melting the raw materials, partial utilization of the flammable gas produced in the reaction, and heat loss due to cooling of the reactor.

Due to the above problems, low productivity and low thermal efficiency due to the low utilization rate of the reactor (ratio of time used for the actual reaction) are factors that lower the economics of the plant. have.

Batch pyrolysis processes all of the raw material melting, pyrolysis, sludge termination, residue cooling, and discharge of residues in one reactor, so the time to perform the pyrolysis reaction, which is the main role of the reactor, is three minutes of the total operating time. 1 degree. In this technology, the raw material melting device and the sludge terminal treatment device are installed at the front and rear of the reactor to disperse the functions used in the pyrolysis reactor to expand the pyrolysis operation rate of the reactor. In addition, there is a batch operation process by putting a molten raw material into the reactor and a metering device for feeding a predetermined amount in the step of taking the sludge out of the reactor and transferring the sludge to the sludge terminal treatment reactor, and by placing a water spray cooling device in the sludge terminal treatment reactor. In order to solve the problems such as long operation time, low operation rate and thermal efficiency of the problems, it is to achieve a new pyrolysis emulsification process capable of continuous operation, convenient operation, high thermal efficiency and high operation rate.

In the present invention, it is to improve the economics by continuously operating the pyrolysis reaction to increase the operating rate of the plant. In a conventional batch plant, all processes such as melting of raw materials, pyrolysis, sludge termination, and residue cooling are performed in one pyrolysis reactor. As a means for solving the problems encountered in the batch operation method, in the present invention, first, by dispersing the function of the pyrolysis reactor by improving the process of placing the raw material melter and the sludge reactor in the front and rear of the reactor, and secondly, Metering tanks are placed between the pyrolysis reactors and between the pyrolysis reactors and the sludge reactors, respectively, to allow a certain amount of transfer. In addition, the present invention is to provide a cooling device for spraying water in the state of fine droplets inside the sludge reactor for the rapid cooling of the residue, and to prevent the sludge before the reaction in the sludge reactor enters the residue discharge device to block the outlet port Put it. Injecting the raw material into the melting apparatus, injecting the molten raw material into the raw material weighing tank in the melting device, injecting the weighed melt into the reactor, transferring the sludge reactor from the pyrolysis reactor to the sludge weighing tank, in the sludge weighing tank Transfer to the sludge reactor, cooling the residue of the sludge reactor and discharge of the residue from the sludge reactor are all intermittently carried out to operate as if the continuous operation is seen as a whole process, high economical pyrolysis It is characterized by excellent process.

According to the present invention, the improvement of the existing batch pyrolysis process is considered in consideration of the small size and marketability of the domestic market, it is expected to be able to significantly improve productivity, improve thermal efficiency, improve product quality and poor working environment and safety.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows schematic structure of the pyrolysis apparatus of this invention.
2 is a view showing a schematic configuration of a cooling device for cooling the residue generated in the sludge reactor in the pyrolysis device according to the present invention.

The schematic configuration of the pyrolysis apparatus of the present invention for achieving the above object is as shown in FIG. The pyrolysis apparatus according to the present invention is a pretreatment raw material input hopper 10, raw material melting tank 13, melt raw material weighing tank 14, pyrolysis reactor 15, sludge weighing tank 17, sludge reactor 18, packing material It consists of a hopper 21, a residue cooling device 22, an oil purification device 24, a condenser 25 and an oil collecting tank 26.

Preferably, the present invention is a method of producing a fuel by thermally decomposing a thermally decomposable substance including plastic, synthetic resin, or waste oil, injecting the pretreated raw material into the raw material melting tank 13, in the pyrolysis reactor (15) Melting the raw material by heating the outer wall of the raw material melting tank 13 by the hot exhaust gas or the burner, and the raw material melted in the raw material melting tank 13 is weighed through the melting raw material weighing tank 14 to pyrolysis reactor 15. Step of thermally decomposing the molten raw material in the pyrolysis reactor (15) to a temperature in the range of 350 to 450 ℃, wax generated by the thermal decomposition in the pyrolysis reactor (15) wax reducing device (16-1) ), Storing the liquefied oil produced through the oil purification device (24) and the condenser (25) in the oil collecting tank (26), withdrawing the sludge after pyrolysis in the pyrolysis reactor (15) to the sludge reactor (18).Discharging, completely pyrolyzing the sludge in the sludge reactor 18 to form a powdery residue, cooling the hot residue in the powder state produced by complete pyrolysis in the sludge reactor 18 to about 150 ° C, And repeatedly discharging the cooled residue to store the residue in the residue collection tank 23 to provide a pyrolysis method in which pyrolysis is continuously performed.

Preferably, in the pyrolysis method according to the present invention, a predetermined amount of molten raw material is added to the pyrolysis reactor 15 to thermally decompose and the sludge in a state in which the remaining unreacted material and the residue are mixed is initially supplied. When remaining at 70% to 10% or less, it is possible to take out the sludge remaining in the pyrolysis reactor 15 by a predetermined amount using the sludge metering tank 17 and send it to the sludge reactor.

In addition, preferably, the pyrolysis method according to the present invention is provided with the filler hopper 21 and the valve 12-7 on the upper end of the screw conveyor 11-5 for discharging the residues, so that the pyrolysis reactor 15 Inside the screw conveyor by filling the powder filling in the passage connecting the screw conveyor (11-5) and the residue cooling device to discharge the residue after the sludge reaction is finished before the sludge is taken out from the lower portion and sent to the sludge reactor (18). And it may further include preventing the sludge is filled in the passage connected to the residue cooling device (22).

Preferably, in the pyrolysis method according to the present invention, by installing a cooling water spray nozzle connector 19 for connecting the cooling water spray nozzle to the top of the reactor and a steam discharge port 20 for discharging the steam generated by spraying the cooling water In the sludge reactor 18, it is possible to cool the hot residue remaining on the bottom after the pyrolysis reaction is completed.

In addition, the present invention is a pyrolysis device for producing a fuel by pyrolyzing pyrolysable substances including plastic, synthetic resin, or waste oil, the raw material pre-treated is input and the raw material introduced by the hot exhaust gas or burner from the pyrolysis reactor (15) Raw material melting tank 13 to melt the; A molten raw material weighing tank 14 which measures the raw materials melted in the raw material melting tank 13 and feeds them into the pyrolysis reactor 15; A pyrolysis reactor 15 for pyrolyzing the molten raw material from the molten raw material weighing tank 14 at a temperature in the range of 350 to 450 캜; An oil collecting tank 26 for collecting oil produced by passing steam generated by pyrolysis in the pyrolysis reactor 15 through the wax reduction device 16, the oil purification device 24, and the condenser 25; A sludge reactor 18 which takes out the sludge after pyrolysis in the pyrolysis reactor 15 and completely decomposes it into a powdery residue; A screw conveyor 11-5 for evacuating the residue from the sludge reactor 18; Provided is a pyrolysis apparatus including a residue collecting tank (23) for cooling and storing a powdery high temperature residue produced by complete pyrolysis in a sludge reactor (18).

Preferably, the pyrolysis device according to the present invention is a screw conveyor (11-5) for withdrawing the sludge from the bottom of the pyrolysis reactor (15) and discharge the residue after the sludge reaction is finished before sending to the sludge reactor (18) Residue discharge screw conveyor (11-5) for filling the powder filling in the passage connected to the residue cooling device to prevent sludge filling in the passage connected to the inside of the screw conveyor and the residue cooling device (22) The filler hopper 21 and the filler hopper 21 at the rear end may further include a valve 12-7 between the upper end of the screw conveyor 11-5 for residue discharge.

In addition, the pyrolysis device according to the present invention is a cooling water spray nozzle for connecting a cooling water spray nozzle to the top of the reactor in order to cool the residue of the high temperature remaining on the bottom after the pyrolysis reaction in the sludge reactor 18 It may further include a steam outlet 20 for discharging the steam generated by injecting the connector 19 and the cooling water.

In addition, the pyrolysis device according to the present invention, the cooling water storage tank 30, the cooling water supply pump 31 in the cooling device to cool the residue of the high temperature remaining in the lower after the reaction is completed in the sludge reactor 18 ), A separate system consisting of a steam treatment system comprising a cooling water supply system for supplying cooling water through a filter 32 and a flow meter 33 and a steam condenser 34 and a condensate collection tank 35 for condensing water vapor from the reactor. It may further comprise a chiller.

In the pyrolysis apparatus according to the present invention, the raw material input hopper 10 has a function of supplying the pretreated raw material to the raw material melting tank 13, the raw material input hopper 10 to the input screw conveyor 11-1 and the valve (12-1) is mounted, the raw material input hopper 10 is filled with raw materials, the valve 12-1 is opened and the screw conveyor 11-1 is operated to feed the raw materials into the raw material melting tank 13 do. The raw material melting tank 13 has a function of melting raw materials by heating, an agitator is installed inside, a shutoff valve 12-2 is provided at the bottom, and an outer wall and an outer cylinder for heating with hot gas are provided. Install the burner. The injected raw material is melted by heating the outer wall of the raw material melting tank 13, and the heating is performed by the hot gas and the auxiliary burner coming from the pyrolysis reactor 15. The molten raw material weighing tank is a device having a function of supplying the molten raw material from the raw material melting tank 13 to the pyrolysis reactor 15 by a predetermined amount, and a predetermined amount of volume having the shutoff valves 12-2 and 3 provided on the upper and lower parts. It is a molten raw material weighing tank 14 having. The molten raw material metering tank 14 is filled with molten raw material by opening the upper valve 12-2 while the lower valve 12-3 is closed, and then closing the upper valve 12-2 and lower valve ( 12-3) is opened and the screwenveyer 11-2 is operated to supply the molten raw material to the pyrolysis reactor 15, and after the supply of the molten raw material is completed, the lower valve 12-3 is restarted. Close it. The pyrolysis reactor receives molten raw materials and heats them to a high temperature in the range of 350 to 450 ° C. to cause thermal decomposition. The raw material input screw conveyor 11-2, sludge discharge screw conveyor 11-3 and wax It is connected to the abatement device 16-1, and the pyrolysis reactor 15 is provided with a double-cylinder outer cylinder and heating burner to heat the outer wall and the bottom. The wax reduction device 16-1 is a device for reducing wax in a product by removing a substance having high boiling point from steam emitted from the pyrolysis reactor 15, and is a conventional wax reduction device. Steam generated by pyrolysis in the pyrolysis reactor (15) is passed through a wax reducing device (16-1), an oil purification device (24) and condensers (25-1, 2), and the oil produced is an oil collecting tank (26-). 1,2). The oil purifier 24 is an oil purifier commonly used in the art, and is a device for purifying steam generated from the pyrolysis reactor 15. The condenser 25 is a condenser commonly used in the art. A means for condensing and liquefying purified steam from an oil refinery. The sludge metering tank 17 has a function of withdrawing a certain amount of sludge from the pyrolysis reactor 15 and sending it to the sludge reactor 18, and having a certain amount of volume having valves 12-4 and 5 installed on the upper and lower portions. As the sludge metering tank 17, it has a double wall structure so that an outer wall can be heated by hot gas. When the sludge is discharged from the pyrolysis reactor, the upper valve 12-4 is opened to fill the sludge metering tank 17 with sludge, and the upper valve 12-4 is closed, and the lower part of the sludge weighing tank 17 is closed. The valve 12-5 is opened and the sludge of the sludge metering tank 17 is introduced into the sludge reactor 18. After closing, the lower valve of the sludge weighing tank 17 is closed. The sludge reactor 18 has a function of receiving a sludge containing a large amount of residue from the pyrolysis reactor 15 to completely pyrolyze it into a powdery residue, and a sludge input screw conveyor 11-4 and a sludge reactor 18. ), A wax reducing device (16-2), a screw conveyor (11-5) for residue discharge, etc., the sludge reactor (18) is provided with an agitator inside, and the outer wall and the bottom are double walls for heating. Burner is installed at the bottom. In addition, the upper portion of the sludge reactor 18 is provided with a cooling water injection nozzle connector 19 and a steam discharge port 20 for cooling the high temperature residue remaining after the reaction. Sludge coming into the sludge reactor 18 is heated to 400 ~ 500 ℃ range is completely pyrolyzed, the oil vapor is sent to the oil purification device through the wax reduction device (16-2), further inside the sludge reactor (18) Only residues which are not abnormally pyrolyzed remain.

The hot residue must be cooled to prevent ignition before discharge to the outside. This cooling process will be described with reference to FIG. 2. When not cooled, the chiller is separated from the sludge reactor 18. If cooling is required, the pipe connected to the rear end of the flow meter 33 of the cooling device is connected to the cooling water injection nozzle connector 19 of the sludge reactor 18, and the pipe connected to the front end of the steam condenser 34 is connected to the steam outlet ( 20). After the connection is completed, when the coolant supply pump 31 is operated to spray coolant into the reactor, the internal temperature of the reactor is lowered. When the cooling is sufficiently performed, the coolant supply pump 31 is stopped, and the previously connected coolant supply pipe and steam discharge are discharged. Disconnect the pipe.

The filling hopper 21 is a means for supplying a filling for preventing the sludge from entering the residue of the screw conveyor 11-5 for discharging the residue. The residue discharge screw conveyor 11-5 is not heated to a high temperature, and if the sludge enters the inside, pyrolysis does not occur and the screw conveyor 11-5 may be blocked. Large quantities remain. Therefore, before supplying the sludge to the sludge reactor 18, a powder-filled filler is put into the filling hopper 21, and the valve 12-7 is opened to fill the filling inside the screw conveyor 11-5 so that the sludge is a screw conveyor ( 11-5) to prevent entry. As such a filler, a material in the form of powder such as sand, soil, residue, etc., which is no longer pyrolyzed is used.

The foregoing description is merely illustrative of the embodiments of the invention and is not intended to limit the invention. The present invention may be variously changed and changed without departing from the spirit and scope described in the claims.

10: Raw material input hopper 11-1 ~ 5: Screw conveyor
12-1 ~ 8: Valve 13: Raw material melting bath
14 molten raw material weighing tank 15 pyrolysis reactor
16-1,2: wax reduction device 17: sludge weighing tank
18: sludge reactor 19: cooling water spray nozzle connector
20: steam outlet 21: filling hopper
22: residue cooling device 23: residue collection tank
24: oil purification device 25-1, 2: condenser
26-1,2: Oil collection tank
30: cooling water storage tank 31: cooling water supply pump
32 filter 33 flow meter
34: steam condenser 35: condensate collection tank

Claims (8)

A method of producing fuel by pyrolyzing pyrolysable materials including plastics, synthetic resins, or waste oil, by injecting pretreated raw materials into the raw material melting tank 13, by hot exhaust gas or burners from the pyrolysis reactor 15. Heating the outer wall of the raw material melting tank 13 to melt the raw materials, measuring the raw material melted in the raw material melting tank 13 through the molten raw material weighing tank 14, and feeding the raw material into the pyrolysis reactor 15, melting Pyrolysis of the raw materials by pyrolysis in the pyrolysis reactor (15) to a temperature in the range of 350 to 450 ℃, vapor generated by pyrolysis in the pyrolysis reactor (15), wax reducing device (16-1), oil purification device (24) And storing the liquefied oil produced through the condenser 25 in the oil collecting tank 26, withdrawing the sludge after pyrolysis in the pyrolysis reactor 15 and sending it to the sludge reactor 18, sludge reactor Pyrolyzing the sludge in (18) to form a powdery residue, cooling the powdery hot residue produced by complete pyrolysis in the sludge reactor 18 to around 150 ° C, and cooled residue A pyrolysis method, characterized in that the operation method to obtain the effect that the pyrolysis is continuously performed by repeatedly performing the process of the step of storing the residue in the residue collection tank (23).
A pyrolysis device for producing fuel by pyrolyzing pyrolysable materials including plastics, synthetic resins, or waste oil, wherein a raw material melt is injected into a pretreated raw material and the raw material melted by a hot exhaust gas or a burner from the pyrolysis reactor 15 is melted. Jaw 13; A molten raw material weighing tank 14 which measures the raw materials melted in the raw material melting tank 13 and feeds them into the pyrolysis reactor 15; A pyrolysis reactor 15 for pyrolyzing the molten raw material from the molten raw material weighing tank 14 at a temperature in the range of 350 to 450 캜; An oil collecting tank 26 for collecting oil produced by passing steam generated by pyrolysis in the pyrolysis reactor 15 through the wax reduction device 16, the oil purification device 24, and the condenser 25; A sludge reactor 18 which takes out the sludge after pyrolysis in the pyrolysis reactor 15 and completely decomposes it into a powdery residue; A screw conveyor 11-5 for evacuating the residue from the sludge reactor 18; A pyrolysis apparatus comprising a residue collecting tank (23) for cooling and storing powdered high temperature residue made by complete pyrolysis in a sludge reactor (18) to around 150 ° C.
The method according to claim 2, wherein the sludge is removed from the bottom of the pyrolysis reactor (15) and connected to a screw conveyor (11-5) for discharging the residue after the sludge reaction is finished before being sent to the sludge reactor (18). Filling hopper in the upper part of the rear end of the residue discharge screw conveyor (11-5) to prevent the sludge filling in the passage connected to the inside of the screw conveyor and the residue cooling device (22) by filling the filler in the powder state 21) and a valve (12-7) between the filler hopper (21) and the top of the rear end of the residue conveyor screw conveyor (11-5).
The cooling water spray nozzle connector (19) and cooling water are sprayed to connect the cooling water spray nozzle to the top of the reactor in order to cool down the hot residue remaining at the bottom after the pyrolysis reaction in the sludge reactor (18). A pyrolysis device, characterized in that it further comprises a steam outlet (20) for discharging the steam generated by.
5. The cooling water storage tank (30), cooling water supply pump (31), filter (32) and flow meter in a cooling apparatus to cool down the hot residue remaining at the bottom after the reaction is completed in the sludge reactor (18). (33) further comprises a separate cooling system consisting of a steam treatment system comprising a cooling water supply system for supplying the cooling water through the condensate and a condensate collecting tank 35 and a steam condenser 34 for condensing water vapor from the reactor. Characterized in that the pyrolysis device.
The method of claim 1, wherein the pyrolysis reaction is carried out by thermally decomposing a predetermined amount of molten raw material in the pyrolysis reactor 15, and the sludge in a state in which the remaining unreacted material and the residue are mixed is 70% to 10% or less of the amount of raw material initially introduced. When remaining, the pyrolysis method characterized in that the sludge remaining in the pyrolysis reactor (15) is taken out by a predetermined amount using a sludge weighing tank (17) and sent to the sludge reactor.
2. The sludge reactor according to claim 1, wherein a filler hopper 21 and a valve 12-7 are provided at the upper end of the residue discharging screw conveyor 11-5, and the sludge is extracted from the lower part of the pyrolysis reactor 15. Screw conveyor 11-5 for discharging the residue after the sludge reaction is finished and powder filling in the passage connected to the residue cooling device before sending to the inside of the screw conveyor and residue cooling device 22. A pyrolysis method characterized in that the sludge is prevented from filling in the passage connected to the furnace.
The sludge reactor (18) according to claim 1, wherein a coolant injection nozzle connector (19) for connecting a coolant injection nozzle (19) and a steam outlet (20) for discharging steam generated by injecting the coolant are installed at the upper end of the reactor. A pyrolysis method, characterized by cooling the hot residue remaining on the bottom after the pyrolysis reaction.

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