KR20220157071A - Waste treatment system - Google Patents

Abstract

The present invention relates to a waste treatment system including: a fluidized bed pyrolysis device in which fluidized gas is supplied and pyrolysis of waste is performed; a combustion device for combusting exhaust gas discharged from the fluidized bed pyrolysis device; and a filter unit positioned on a supply path through which the waste is supplied to the fluidized bed pyrolysis device to select waste particles.

Description

Waste treatment system {WASTE TREATMENT SYSTEM}

The present invention relates to a waste disposal system. Specifically, the present invention relates to a waste treatment system for thermally decomposing waste using a fluidized bed pyrolysis device.

In general, various domestic wastes generated at home and industrial wastes generated at industrial sites are partially recycled through separate collection, etc. is being processed in a way that

1 is a view showing a conventional wastewater treatment process. In a conventional wastewater treatment process, wastewater is sludged through an aeration tank and a sludge settling unit, and then the sludge containing harmful substances is landfilled or incinerated.

However, industrial waste and wastewater generate harmful chlorine compounds such as dioxins as unwanted by-products in various product production processes such as chemical processes, pulp processes, and incineration processes. Dioxin contained in waste and sludge is released into soil, water and air.

In addition, the high-temperature exhaust gas generated in the process of incinerating the waste is gradually cooled in the air, causing a problem in that a small amount of decomposed dioxin is regenerated.

Korean Patent Registration No. 10-1753204 Korea Patent Registration No. 10-2198080

Focusing on the problems of the prior art described above, the present invention is to provide a waste treatment system for decomposing and treating harmful compounds contained in waste and preventing them from being regenerated in the air.

A fluidized bed pyrolysis device in which the fluidizing gas of the present invention is supplied and thermal decomposition of waste is performed; a combustion device that burns exhaust gas discharged from the fluidized bed pyrolysis device; and a filter unit positioned on a supply path through which the waste is supplied to the fluidized bed pyrolysis device to select waste particles.

In another embodiment of the present invention, a drying device for drying the waste before the waste is introduced into the fluidized bed pyrolysis device, wherein the drying device is provided with a particle discharge unit for discharging the dried waste, The filter unit provides a waste disposal system located in the particle discharge unit.

In another embodiment of the present invention, the fluidized bed pyrolysis device pyrolyzes the waste to generate the exhaust gas and pyrolysis sludge, separates the exhaust gas and the pyrolysis sludge supplied from the fluidized bed pyrolysis device, and It provides a waste treatment system further comprising a dust collector for supplying exhaust gas to the combustion device.

In the case of using the waste treatment system according to the embodiment of the present invention, it is possible to decompose harmful compounds included in the waste.

In addition, harmful substances included in the final exhaust gas can be reduced by completely decomposing and removing harmful compounds through two thermal decomposition and cooling.

In addition, by inducing the flow of waste particles during pyrolysis, heat transfer of the waste particles is increased, and uneven treatment of harmful chlorine compounds contained in the waste can be prevented.

1 is a conceptual diagram illustrating a conventional waste treatment process.
2 is a block diagram showing a waste treatment system according to an exemplary embodiment of the present invention.
3 is a block diagram showing a waste treatment system according to another embodiment of the present invention.
4 is a front view showing a fluidized bed pyrolysis device according to an exemplary embodiment of the present invention.
5(a) is a plan view showing a filter unit according to an exemplary embodiment of the present invention, and FIG. 5(b) is a cross-sectional view showing a filter unit installed according to an exemplary embodiment of the present invention.
6 is a cross-sectional view showing a drying apparatus according to an exemplary embodiment of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. However, the drawings are for illustrating the present invention, and the scope of the present invention is not limited by the drawings.

2 is a configuration diagram showing a waste disposal system 100 according to an exemplary embodiment of the present invention, and FIG. 5 (a) is a plan view showing a filter unit 30 according to an exemplary embodiment of the present invention. 5(b) is a cross-sectional view showing that the filter unit 30 according to an exemplary embodiment of the present invention is installed.

A waste treatment system 100 according to the present invention includes a fluidized bed pyrolysis device 10, a combustion device 20 and a filter unit 30.

4 is a cross-sectional view showing a fluidized bed pyrolysis device 10 according to an exemplary embodiment of the present invention.

In the fluidized bed pyrolysis device 10, a fluidized gas is supplied from the bottom and waste is pyrolyzed, and the waste is decomposed into exhaust gas and pyrolysis sludge. Here, pyrolysis sludge means sludge in liquid and solid form. The waste supplied to the fluidized bed pyrolysis device 10 contains harmful chlorine compounds, and the harmful chlorine compounds are included in the exhaust gas and transported to the combustion device 20 . In addition, the pyrolysis sludge may remain in the fluidized bed pyrolysis device 10 or may be separated and discharged along a path moving to the combustion device 20 together with the exhaust gas.

The fluidized bed pyrolysis device 10 includes a particle inlet 12 into which waste particles having a certain particle size or less are introduced, a fluidized gas inlet 13 into which particulate waste flows, and exhaust gas and pyrolysis sludge generated by pyrolysis. It includes a discharge unit 14 for discharging any one or more and a sieve 15 for preventing particulate waste and pyrolysis sludge from flowing into the fluidizing gas inlet 13.

In the fluidized bed pyrolysis device 10, any one of a conveyor belt, a moving screw, a feeder, and a pneumatic conveying device may be provided in front of the particle inlet 12 to continuously receive waste.

The fluidized bed pyrolysis device 10 may pyrolyze waste by forming an inside of the pyrolysis temperature atmosphere. The fluidized bed pyrolysis device 10 may heat the flowing gas to form the inside of the pyrolysis temperature atmosphere, or apply heat from the outside to form the inside of the pyrolysis temperature atmosphere.

Therefore, the fluidized bed pyrolysis device 10 may further include a fluidizing gas heating unit 11 for heating the fluidizing gas before the fluidizing gas is supplied, or a heater (not shown) capable of increasing the internal temperature may be provided on the outer circumferential surface. can

That is, the fluidized bed pyrolysis device 10 has an effect of increasing the pyrolysis efficiency of the waste by increasing the contact area between the high-temperature fluidized gas or the fluidized gas heated by a heater and the waste by fluidizing the waste in the form of particles.

The fluidized bed pyrolysis device 10 is characterized in that the inside is maintained in an oxygen-free or low-oxygen atmosphere.

When the internal atmosphere of the fluidized bed pyrolysis device 10 is a low-oxygen or anoxic atmosphere, at a temperature of 200 ° C. to 600 ° C. and under the low-oxygen or anoxic condition, the dechlorination reaction in which the C-Cl bond of the harmful chlorine compound in the waste is broken, and the harmful chlorine Partial and complete degradation of the compound can occur smoothly. On the other hand, under conditions where oxygen is present in an amount exceeding 3 vol%, oxygen reacts with organic matter and harmful chlorine compounds in the waste to form another harmful chlorine compound or the decomposed harmful chlorine compound may be re-synthesized.

The low-oxygen or oxygen-free atmosphere is not limited to a specific gas, and may be, for example, a nitrogen atmosphere, an inert atmosphere, or a vacuum atmosphere. An argon atmosphere or a helium atmosphere may be used as the inert atmosphere, but is not limited thereto. Among them, when a nitrogen atmosphere is applied to a low-oxygen or non-oxygen atmosphere, it is economical because relatively inexpensive nitrogen can be used, and there are advantages in that the atmosphere is easy to create. A hypoxic or anoxic atmosphere can be controlled by introducing a carrier gas into the pyrolysis unit.

Therefore, the fluidized bed pyrolysis apparatus 10 according to the present invention may further include a supply unit for supplying a carrier gas, or may supply a carrier gas through either a particle inlet or a fluidized gas inlet.

The combustion device 20 burns the exhaust gas discharged from the fluidized bed pyrolysis device 10, and decomposes the exhaust gas into low-molecular substances by burning the exhaust gas at a high temperature.

In the fluidized bed pyrolysis device 10, harmful chlorine compounds in waste are decomposed to form gas (exhaust gas), and some of the gas components formed may still have harmful properties. Therefore, it is necessary to additionally burn and remove harmful chlorine compounds in a gaseous state.

The combustion device 20 according to the present invention burns the exhaust gas to convert harmful chlorine compounds remaining in the exhaust gas into harmless low-molecular compounds such as carbon dioxide and water, which are difficult to synthesize.

The combustion device 20 includes a combustion burner located on one side of the inside, an exhaust gas supply unit connected to the discharge unit 14 of the fluidized bed pyrolysis device 10 to receive exhaust gas, and a purification gas discharge for discharging the burned exhaust gas to the atmosphere. includes wealth

In the combustion device 20 , an exhaust gas supply unit and a purification gas discharge port may be connected to a passage pipe to prevent mixing of exhaust gas supplied and purification gas purified after combustion. Here, the flow pipe may be formed in various shapes such as a straight line or a spiral, but is preferably formed in a spiral shape to increase the contact time and area with the combustion heat generated from the combustion burner.

The combustion device 20 may receive exhaust gas and pyrolysis sludge from the outlet 14 of the fluidized bed pyrolysis device 10 . At this time, the combustion device 20 is provided with a classification unit for classifying the pyrolysis sludge at the front end of the flow pipe, and can separate and discharge the pyrolysis sludge by gravity and the weight difference between the exhaust gas and the pyrolysis sludge.

And, the combustion device 20 may further include a combustion promoting gas supply port for supplying combustion promoting gas to the interior or flow pipe to promote combustion of the exhaust gas. Here, the combustion-promoting gas means that the content of oxygen is at least 5% by volume or more in the total gas content.

In one embodiment, the waste treatment system 100 according to the present invention includes the discharge unit 14 of the fluidized bed pyrolysis device 10 and the combustion device ( Combustion promoting gas may be supplied to a pipe connecting the exhaust gas supply unit of 20).

In the waste treatment system 100 according to the present invention, a duct connects the discharge part 14 of the fluidized bed pyrolysis device 10 and the exhaust gas supply port of the combustion device 20, or the pyrolysis discharge part 14 and the exhaust gas supply A blower may be included in a pipe connecting the parts to induce supply of exhaust gas to the combustion device 20 .

Referring to FIG. 5 , the filter unit 30 is positioned on a supply path through which waste is supplied to the fluidized bed pyrolysis device 10 to sort out waste particles. The filter unit 30 may select particles having a particle size of 3 mm or less and introduce them into the fluidized bed pyrolysis device 10 . Here, the particle size may mean the longest length of waste particles based on the cross section of the waste particles.

If the particle size of the waste particles exceeds 3 mm, the heat transfer rate to the inside of the waste particles is reduced in the fluidized bed pyrolysis device 10, and thus harmful chlorine compounds contained in the waste particles may not be decomposed.

The filter unit 30 according to the present invention may be provided in the form of a plurality of holes formed by perforation or in the form of a mesh. At this time, it is preferable that the perforation size and the line width of the mesh are 3 mm or less. However, the filter unit 30 according to the present invention is not particularly limited as long as it is in the form of screening waste particles having a particle size smaller than the standard size.

In one embodiment, the filter unit 30 may be provided in the particle inlet 12 of the fluidized bed pyrolysis device 10 . Waste particles exceeding 3 mm that have not been screened by the filter unit 30 are re-supplied to the particle inlet 12, or are additionally put into a device capable of decomposing waste and then re-supplied to the particle inlet 12. can

However, the filter unit 30 is not particularly limited as long as it is a position capable of sorting waste particles before the waste particles are introduced into the fluidized bed pyrolysis device 10 .

3 is a block diagram showing a waste disposal system 100' according to another embodiment of the present invention.

A waste treatment system 100' according to another embodiment includes a dehydration device 60, a drying device 40, a fluidized bed pyrolysis device 10, a dust collector 50, a combustion device 20, a cooling device 70, and It includes a scrubber 80.

Since the fluidized bed pyrolysis device 10, the combustion device 20, and the filter unit 30 are the same as the waste treatment system 100 according to an embodiment, detailed descriptions thereof will be omitted.

6 is a cross-sectional view showing a drying device 40 according to an exemplary embodiment of the present invention. The drying device 40 receives and dries the waste before the waste is introduced into the fluidized bed pyrolysis device 10, and reduces only the liquid content of the waste at a temperature at which harmful chlorine compounds contained in the waste are not pyrolyzed or burned. . And, the drying device 40 may crush the waste to a certain particle size or less.

The drying device 40 includes a main body that determines the shape of the drying device 40, a waste input unit 41 provided at the front end of the main body to input waste, and a particle discharge device provided at the rear end of the main body to discharge dried and pulverized waste particles. Part 42, steam is supplied to transfer heat to the disk or rotary blade provided on the outer circumferential surface, and the moving disk or moving screw for moving the waste through rotation, the waste gas discharge unit for discharging the waste gas generated as the waste is dried. include

The drying device 40 may include a method in which high-temperature gas directly contacts the waste, or may include a method in which waste is dried in a non-contact manner using a disk or screw capable of receiving heat from the high-temperature gas. .

In one embodiment, the drying apparatus 40 according to the present invention increases the temperature of the disk or screw by supplying the high-temperature gas to the rotating shaft of the moving disk or moving screw in a way that the hot gas does not contact the waste. can make it

And, the drying device 40 may move the waste from the front end to the rear end of the main body through rotation. In addition, the drying device 40 may increase the efficiency of drying the waste by pulverizing the waste to increase the contact area between the hot gas or the high-temperature medium and the waste.

The drying device 40 may include a disc dryer, a ribbon dryer, a twin screw dryer, a paddle dryer, and the like.

However, the drying device 40 is not particularly limited as long as it can continuously dry and pulverize waste.

The drying device 40 is located in front of the fluidized bed pyrolysis device 10, the particle outlet 42 and the particle inlet 12 are connected, and the waste particles are removed from the drying device 40 to the fluidized bed pyrolysis device 10. Any one of a conveyor belt, a moving screw, a feeder, and a powder conveying device (Pneumatic Conveying) may be provided to move to.

In the waste disposal system 100' according to another embodiment, the filter unit 30 may be located in the particle discharge unit 42 of the drying device 40. The filter unit 30 selects waste particles having a particle size of 3 mm or less and supplies them to the fluidized bed pyrolysis device 10. And, if the particle size exceeds 3 mm, it may remain in the drying device 40 and continue to be pulverized by a disk or screw.

The dewatering device 60 dehydrates the waste before it is supplied to the drying device 40 and is located between the waste storage unit and the drying device 40 . At this time, the waste pump may move the waste from the waste storage unit to the dewatering device 60 . In addition, the movement of the sludge from the dewatering device 60 to the drying device 40 may use any one of gravity, a moving screw, and a conveyor belt.

The dust collector 60 is located between the fluidized bed pyrolysis device 20 and the combustion device 30, receives exhaust gas and pyrolysis sludge from the fluidized bed pyrolysis device 20, and separates exhaust gas, liquid and solid particles.

The dust collector 60 may include any one or more of a cyclone and a bag filter. Furthermore, the cyclone may include one having a bag filter therein.

However, the dust collector 60 is not limited as long as it can separate exhaust gas and pyrolysis sludge.

In one embodiment, when the dust collector 60 according to the present invention is a cyclone, the dust collector 60 may separate exhaust gas and pyrolysis sludge using centrifugal force and inertial force.

And, the dust collector 50 may be provided with a pyrolysis sludge supply port through which exhaust gas and pyrolysis sludge are supplied to the upper side of the outer circumferential surface. Therefore, in the dust collector 50, the exhaust gas and pyrolysis sludge supplied from the upper side collide with the inner wall to rotate, and the exhaust gas and pyrolysis sludge to rotate have centrifugal and inertial forces.

In the dust collector 50, light exhaust gas is discharged upward, and pyrolysis sludge is heavy and discharged downward.

Therefore, the dust collector 50 may have an exhaust gas discharge port through which exhaust gas is discharged at the upper side and a pyrolysis sludge discharge port through which pyrolysis sludge is discharged at the lower side.

The dust collector 50 may further include a pyrolysis sludge storage unit 51 for storing pyrolysis sludge.

The pyrolysis sludge storage unit 51 is connected to the pyrolysis sludge discharge port to store the pyrolyzed pyrolysis sludge and measure the concentration of harmful chlorine compounds in the pyrolysis sludge. When harmful chlorine compounds are detected in the pyrolysis sludge storage unit 51, the pyrolysis sludge is transferred to the fluidized bed pyrolysis unit 10, the drying unit 40, the particle waste feeder, and the particle discharge unit 42 and the particle inlet unit 12. ) can be re-supplyed to any one or more of the piping connecting them.

Combustion promoting gas may be supplied to the dust collector 50 to increase the combustion efficiency of the exhaust gas in the combustion device 20 . The location of the combustion-promoting gas supply unit for supplying the combustion-promoting gas is not limited as long as the direction in which the exhaust gas and pyrolysis sludge are turned inside the dust collector 50 is not hindered.

In one embodiment, the combustion-promoting gas supply unit may be provided on the same line as the location where the exhaust gas inlet is provided in the longitudinal direction or in the circumferential direction of the main body of the dust collector 50.

The cooling device 70 rapidly cools the exhaust gas discharged from the combustion device 20 .

In one embodiment, the cooling device 70 may be provided in the form of a cooling tube wound around a container in which exhaust gas is stored. The cooling device 70 has a low internal temperature by means of a cooling pipe, and rapidly cools exhaust gas having a high temperature due to high-temperature combustion.

The cooling device 70 may include a plurality of containers having different temperatures.

In another embodiment, the cooling device 70 may be formed on an outer surface of a pipe through which exhaust gas is discharged from the combustion device 20 . By forming a cooling pipe on the outer surface of the pipe through which the exhaust gas is discharged, the exhaust gas can be rapidly cooled at the same time as the exhaust gas is discharged.

Cooling water or gas such as carbon dioxide or helium may be supplied to the inside of the cooling pipe.

The scrubber 80 filters the exhaust gas cooled in the cooling device 70 and discharges the purified gas. The scrubber 80 according to the present invention is a wet scrubber and may include an organic solvent scrubber and a base solution scrubber. At this time, one or more organic solvent scrubbers may be provided.

The scrubber 80 includes a measuring unit (not shown), and the measuring unit can measure the concentration of organic matter and harmful chlorine compounds in the waste liquid discharged after filtering.

The measuring unit can recover the waste liquid to the sludge storage unit when the concentrations of organic matter and harmful chlorine compounds in the waste liquid are measured above a certain standard.

The waste disposal system 100' according to another embodiment may further include a dust collector (not shown).

The dust collector includes a bag filter and is connected to the scrubber 80 to receive filtered purified gas and remove fine particles included in the gas.

Also, in the waste disposal system 100' according to another embodiment, a blower (not shown) may be further included in a pipe through which air purified by the dust collector is discharged.

The waste disposal system (100, 100') according to the present invention includes an opening and closing device capable of opening and closing the supply inlet, inlet and outlet of each configuration, and a valve is included in the pipe connecting the supply inlet and the inlet and the outlet, The internal atmosphere, temperature, flow rate of sludge or exhaust gas, etc. of each component can be adjusted.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art will variously modify and change the present invention within the scope not departing from the spirit and scope of the present invention described in the claims below. You will understand that it can be done.

100, 100': waste treatment system
10: Fluidized bed pyrolysis unit
11: moving gas heating unit
12: particle inlet
13: flowing gas inlet
14: pyrolysis sludge outlet
15: strainer
20: combustion device
30: filter unit
40: drying device
41: waste input unit
42: particle discharge unit
50: dust collector
51: pyrolysis sludge storage unit
60: dewatering device
70: cooling device
80: scrubber

Claims (14)

A fluidized bed pyrolysis device in which a fluidized gas is supplied and pyrolysis of waste is performed;
a combustion device that burns exhaust gas discharged from the fluidized bed pyrolysis device; and
A filter unit positioned on a supply path through which the waste is supplied to the fluidized bed pyrolysis device to select waste particles
Waste treatment system comprising a. According to claim 1,
Further comprising a drying device for drying the waste before the waste is introduced into the fluidized bed pyrolysis device,
The drying device is provided with a particle discharge unit for discharging the dried waste, and the filter unit is located in the particle discharge unit. According to claim 1,
The fluidized bed pyrolysis device is provided with a particle inlet into which the waste is introduced,
The waste disposal system of claim 1 , wherein the filter unit is positioned at the particle inlet. According to claim 3,
The filter unit selects particles having a particle size of 3 mm or less and introduces them into the fluidized bed pyrolysis device. According to claim 1,
The fluidized bed pyrolysis device is provided with a fluidized gas inlet into which the fluidized gas is introduced,
A waste disposal system comprising a sieve for preventing the waste from entering the flowing gas inlet. According to claim 1,
The fluidized bed pyrolysis device further comprises a fluidized gas heating unit for heating the fluidized gas. According to claim 1,
The fluidized bed pyrolysis device is a waste treatment system in which the inside is maintained in an anoxic or hypoxic atmosphere. According to claim 1,
The combustion device is a waste treatment system in which combustion promoting gas is supplied therein. According to claim 1,
The fluidized bed pyrolysis device pyrolyzes the waste to produce the exhaust gas and pyrolysis sludge and supplies them to the combustion device. According to claim 9,
and a dust collector configured to receive and separate the exhaust gas and the pyrolysis sludge from the fluidized bed pyrolysis device and supply the exhaust gas to the combustion device. According to claim 10,
The dust collector is a waste treatment system comprising at least one of a cyclone and a bag filter. According to claim 10,
A waste treatment system for supplying a combustion promoting gas to at least one of the dust collector and the combustion device. According to claim 1,
The combustion device includes a purification gas discharge unit for discharging a purification gas generated by burning the exhaust gas, and a cooling device positioned at one side of the purification gas discharge unit to rapidly cool the purification gas. According to claim 13,
Waste treatment system further comprising a scrubber for filtering the rapidly cooled purification gas and discharging the filtered gas to the outside.

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