KR102334096B1 - Apparatus for decreasing chlorine of pyloysis of mixture of plastics comprising polyvinyl chloride and method for decreasing chlorine of pyloysis of mixture of plastics comprising polyvinyl chloride using the same - Google Patents

Abstract

Disclosed herein are a chlorine reduction device for a plastic mixture containing polyvinyl chloride and a method for reducing chlorine from a polyvinyl chloride-containing plastic mixture using the same. The chlorine reduction device of the plastic mixture containing polyvinyl chloride, which is an aspect of the present invention, includes a continuous stirring tank reactor, so that the residence time can be adjusted so that hydrogen chloride can be sufficiently desorbed from the PVC, so that from the PVC mixed waste plastic A pyrolysis oil in which chlorine is effectively reduced can be obtained.

Description

Apparatus for reducing chlorine in pyrolysis of a plastic mixture containing polyvinyl chloride and a method for reducing chlorine in pyrolysis of a plastic mixture containing polyvinyl chloride using the same OF MIXTURE OF PLASTICS COMPRISING POLYVINYL CHLORIDE USING THE SAME}

Disclosed herein are an apparatus for reducing chlorine generated during thermal decomposition of a plastic mixture containing polyvinyl chloride and a method for reducing chlorine generated during thermal decomposition of a polyvinyl chloride-containing plastic mixture using the same.

In Korea, about 4 million tons of plastic waste is generated every year, but the recycling rate is low at 20-30%, and a large amount is disposed of through landfill or incineration. However, the method of burying waste plastics has problems in that harmful components may be eluted from the waste plastics, and storage, transportation and landfilling are difficult due to the large volume compared to the unit weight. In addition, the treatment by incineration can utilize a part of the thermal energy generated during plastic incineration as an energy source, but there is a problem that it is uneconomical by discharging a toxic gas fatal to the human body and the environment. Accordingly, social interest in a method of recycling waste plastics is increasing.

The method of recycling waste plastic is largely a mechanical recycling method, which melts the waste plastic at around 300 ° C It is divided into a feedstock recycling method that converts it. Among them, in the mechanical recycling method, the physical properties of the product manufactured by the process fall every time the mechanical recycling is repeated, so the feedstock recycling method is preferred as the final recycling method. Feedstock recycling methods are largely divided into pyrolysis, gasification, hydrogenation, and solvolysis, and pyrolysis is the most actively studied among them. The pyrolysis oil produced from waste plastics through pyrolysis is put into the petroleum refining process to be used as a raw material for new chemicals or fuels.

Specifically, pyrolysis is an eco-friendly waste plastic recycling method that thermally decomposes waste plastics under anoxic conditions to produce oil, gas, and char, a solid product. The success or failure of pyrolysis of waste plastics is directly related to the removal of chlorine or chlorine compounds. PVC (polyvinyl chloride) is mixed in the waste plastics generated in the city. Chlorine compounds (HCl, etc.) generated during pyrolysis of PVC cause corrosion in the process during pyrolysis, and when pyrolysis oil containing this is burned, the lifespan of incineration facilities It causes shortening and causes dioxin generation.

For this reason, it is essential for pyrolysis of waste plastics to control chlorine compounds generated during thermal decomposition of waste plastics containing PVC and finally develop a method to effectively reduce the chlorine content of pyrolysis oil. However, there have been no reports of cases in which chlorine was reduced to a satisfactory level in pyrolysis oil of waste plastics. It is known that pyrolysis oil produced by pyrolyzing waste plastics containing PVC in Korea contains about 10,000 ppm or more of chlorine. In order for the practical use of waste plastic pyrolysis oil, the chlorine content in the oil should be 10 ppm or less, but pyrolysis oil having a chlorine content within this value is not actually produced (Energy Conversion and Management 115 (2016) 308-326). ).

Accordingly, the present inventor has introduced a technology for reducing the chlorine content from pyrolysis oil through Patent Application No. 10-2017-0082051, but the thermal decomposition of PVC-containing plastics in the auger reactor is not sufficiently performed, so this The invention was completed.

Korean Patent Application No. 10-2017-0082051

In one aspect, an object of the present invention is to prepare a pyrolysis oil suitable for recycling of waste plastics containing PVC.

In one aspect, an object of the present invention is to minimize the content of chlorine in oil, which is a pyrolysis product of waste plastics.

In order to achieve the above object, the present invention in one aspect, a continuous stirred tank reactor (CSTR); And it provides an apparatus for reducing chlorine of a plastic mixture comprising polyvinyl chloride, comprising a fluidized bed reactor.

The chlorine reduction device of the plastic mixture containing polyvinyl chloride, which is an aspect of the present invention, includes a continuous stirring tank reactor, so that the residence time can be adjusted so that hydrogen chloride can be sufficiently desorbed from the PVC, so that from the PVC mixed waste plastic A pyrolysis oil in which chlorine is effectively reduced can be obtained.

1 is a schematic view of a system comprising a chlorine-reducing window paper of a plastic mixture comprising polyvinyl chloride according to an aspect of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art can easily implement them. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

The terms or words used in the specification and claims of the present invention are not to be construed as limited in their ordinary or dictionary meanings, and the inventor can appropriately define the concept of the term in order to best describe his invention. Based on the principle, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

In the entire specification of the present invention, when a part "includes" a component, it means that other components may be further included, rather than excluding other components, unless otherwise stated. .

Throughout the specification of the present invention, "A and/or B" means A or B, or A and B.

Hereinafter, the present invention will be specifically described with reference to the accompanying drawings, but the present invention is not limited thereto.

The present invention in one aspect, a continuous stirred tank reactor (CSTR); and a fluidized bed reactor, a chlorine reduction device for a plastic mixture comprising polyvinyl chloride.

In one aspect, the apparatus includes a continuously stirred tank reactor, so that the residence time can be adjusted, and thus hydrogen chloride can be sufficiently desorbed from the PVC.

In one embodiment, the residence time of the plastic mixture in the continuously stirred tank reactor may be about 5 minutes to 30 minutes.

In one aspect, the apparatus may include pyrolyzing a plastic mixture including polyvinyl chloride.

Thermal decomposition may mean decomposing chemicals included in the pyrolysis target by heating the pyrolysis target under conditions excluding oxygen.

The chlorine reduction apparatus for a plastic mixture containing polyvinyl chloride according to an aspect of the present invention includes a continuous stirred tank reactor and a fluidized bed reactor, and a fluidized bed reactor may be located behind the continuous stirred tank reactor. In this case, between the continuous stirred tank reactor and the fluidized bed reactor, a melt hopper for temporarily storing the plastic mixture in a melt state and a feeder for feeding the melt to the fluidized bed reactor may be located.

When a plastic mixture containing PVC, waste plastic or its powder (hereinafter, referred to as a plastic mixture, etc.) is put into the reactor of the continuous stirring tank in the apparatus of the present invention, the same as hydrogen chloride from the plastic mixture by thermal decomposition in the continuous stirring tank reactor Chlorine compounds (in gaseous or liquid form) are separated and released, forming fractions such as plastic mixtures with reduced chlorine content (primary pyrolysis products). At this time, the apparatus may further include a pyrolyzate separator connected to the continuous stirred tank reactor. The pyrolysis product separator is installed on the upper part of the continuous stirred tank reactor, and may serve to discharge gaseous hydrogen chloride. The pyrolyzate separator may include, for example, a separator in which the pyrolyzate introduced from the reactor collides and a baffle colliding with the separator to induce a downward flow of the separated pyrolyzate. The baffle may be inclined downward from one end to the other so that the pyrolyzate separated by colliding with the separator is seated on one end of the baffle and flows to the other end. Specifically, the baffles include a plurality of baffles spaced apart from each other and disposed vertically, and the baffles include: a first baffle; and a second baffle positioned below the first baffle, wherein the pyrolyzate is seated on one end of the first baffle and flows to the other end of the first baffle, and the pyrolyzate introduced from the other end of the first baffle is It may be seated on one end of the second baffle and flow to the other end of the second baffle. The pyrolyzate separator may include a cooling unit, and in one embodiment, the cooling unit may include a water cooler. When the cooling unit is constituted by a water cooler, the high boiling point waxes rising to the pyrolyzate fractionator are condensed as they pass through the cooling unit, collide with the baffle several times and separate from the rising gaseous HCl, and fall into the continuous stirring reactor. . Therefore, it is possible to increase the yield of the final product, the oil.

The operating temperature of the pyrolysis product separator including the water cooler may be 15 ~ 30 ℃.

In one embodiment, a gas curtain film may be formed between the continuous agitation tank reactor and the melt hopper by the gas introduced through the gas input unit. Through this, the chlorine compound gas separated from the plastic mixture, etc. by the gas curtain film is prevented from being transferred to the fluidized bed reactor while the fraction such as the plastic mixture having the reduced chlorine content is introduced into the melt hopper and the fluidized bed reactor. . The gas introduced through the gas input unit (not shown) is preferably an inert gas, and the inert gas may be nitrogen gas, helium gas, or argon gas.

On the other hand, a fluidized bed reactor requires a fluidizing gas, and as the fluidizing gas, an inert gas, a gas generated and discharged from the apparatus, in particular, a non-condensed gas discharged from the fluidized bed reactor, or a mixture thereof may be used.

The continuous stirred tank reactor may include a discharge unit (not shown) through which the generated product is discharged. The discharge part of the continuous stirred tank reactor may be directly connected to the pyrolysis product separator.

On the other hand, the pyrolysis char, which is a solid, is first collected in the pyrolysis product discharged from the secondary pyrolysis in the fluidized bed reactor, and the pyrolysis gas is converted into oil through cooling and condensation processes and collected.

In addition, the apparatus may further include a hot filter group filled with calcium oxide, calcium hydroxide, or sodium carbonate (Na ₂ CO ₃ ), and the high temperature filter group may be located behind the fluidized bed reactor. For example, calcium oxide reacts with hydrogen chloride to form calcium chloride, which lowers the chlorine content in the pyrolysis oil.

The temperature of the high-temperature filter may be 400 ~ 700 ℃, the calcium oxide and calcium hydroxide may include a granular form heat-treated at 850 ~ 1000 ℃. In one embodiment, when finely divided calcium oxide or calcium hydroxide other than the heat-treated calcium oxide or calcium hydroxide is used at the above temperature, a differential pressure in the reactor may occur, thereby reducing process operation efficiency.

The apparatus for reducing chlorine in a plastic mixture containing polyvinyl chloride may further include a temperature control device (not shown), wherein the temperature control device controls the temperature of each of the continuous stirred tank reactor, the fluidized bed reactor, and the high temperature filter. It is desirable to be able to independently change . The temperature control device may include a temperature detection unit, a temperature control unit, and a heating unit.

Further, in one aspect, the present invention may be a system for chlorine reduction of a plastic mixture, the system comprising an apparatus for chlorine reduction of a PVC-containing plastic mixture, a plastic mixture supply system, a pyrolysis char separation system, an electrostatic precipitator and a gas circulation system (not shown) and the like.

The temperature of the continuous stirred tank reactor may be 250 ~ 350 ℃, preferably 250 ~ 300 ℃.

In addition, in the fluidized bed reactor, the PVC-containing plastic mixture pyrolyzed in the auger reactor and the pyrolyzate separator may be pyrolyzed again. In the above aspect, the internal temperature of the fluidized bed reactor may be 650 ~ 780 ℃, preferably, 700 ~ 750 ℃, more preferably, may be 700 ~ 720 ℃.

The plastic mixture may include waste plastic containing PVC. In addition, the plastic mixture containing PVC further comprises one or more of polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polystyrene (PS), and polypropylene (PP) in addition to PVC. may mean a mixture of

In one aspect, the content of chlorine in the oil in the product produced by the apparatus may be 10 ppm (w/w) or less.

The chlorine content in the oil in the product produced by the device is significantly lower than the known pyrolysis oil chlorine content of 10,000 ppm.

In one aspect, the present invention is a method for reducing chlorine from a plastic mixture comprising polyvinyl chloride (PVC) using the apparatus.

The method may be for reducing the content of chlorine in pyrolysis oil produced from a plastic mixture comprising polyvinyl chloride (PVC).

In one aspect, the method comprises: a first pyrolysis step of pyrolyzing a plastic mixture containing PVC in a continuously stirred tank reactor; a pyrolyzate separation step of removing chlorine from the pyrolyzed product pyrolyzed in the continuous stirred tank reactor; a second pyrolysis step of pyrolysis in a fluidized bed reactor; and filtering the pyrolysis vapor of the PVC plastic mixture pyrolyzed in the fluidized bed reactor in a high-temperature filter filled with calcium oxide or calcium hydroxide.

In one embodiment, the first pyrolysis step may be performed at 280 ~ 400 ℃. In addition, the temperature of the pyrolyzate separator is 300 ~ 500 ℃, the second pyrolysis step, may be performed at 680 ~ 750 ℃, preferably, 700 ~ 750 ℃, more preferably, 700 ~ 720 ℃ can be performed in

Hereinafter, the configuration and effect of the present invention will be described in more detail with reference to Examples and Test Examples. However, these Examples and Test Examples are provided only for the purpose of illustration to help the understanding of the present invention, and the scope and scope of the present invention are not limited by the following examples.

1: Systems for chlorine reduction in plastic mixtures
2: Continuously stirred tank reactor
3: melt hopper
4: Feeder
5: fluidized bed reactor
6: cyclone
7: hot filter
8: chiller
9: Electrostatic precipitator
10: compressor
11: preheater

Claims (11)

As an apparatus for reducing chlorine of a plastic mixture comprising polyvinyl chloride (PVC),
The device is
continuous stirred tank reactor; and a fluidized bed reactor,
The continuous stirred tank reactor and the fluidized bed reactor,
It includes a continuous stirred tank reactor, and a fluidized bed reactor connected in series in that order,
Thermal decomposition is carried out in the continuous stirred tank reactor,
The device is
Containing a pyrolysis product separator connected to a continuous stirred tank reactor,
The continuous stirring tank reactor temperature is 250 ~ 350 ℃,
The temperature of the fluidized bed reactor is 650 ~ 780 ℃,
The operating temperature of the pyrolysis product separator is 15 ~ 30 ℃,
The pyrolyzate separator includes a separator and a plurality of baffles,
The pyrolyzate introduced into the pyrolyzate separator from the continuous stirred tank reactor collides with the separator,
The pyrolyzate collided with the separator is seated on one end of the plurality of baffles and flows downward while flowing to the other end, a chlorine reduction device for a plastic mixture containing polyvinyl chloride. According to claim 1,
The device is
An apparatus for reducing chlorine in a plastic mixture containing polyvinyl chloride, which thermally decomposes a plastic mixture containing polyvinyl chloride. delete delete According to claim 1,
The pyrolyzate separator includes a cooling unit, a chlorine reduction device for a plastic mixture containing polyvinyl chloride. delete delete According to claim 1,
The device is a chlorine reduction device for a plastic mixture containing polyvinyl chloride, further comprising a high-temperature filter. According to claim 1,
The plastic is a chlorine reduction device for a plastic mixture containing polyvinyl chloride, including waste plastic. According to claim 1,
The product produced from the device is
A chlorine reduction device for a plastic mixture containing polyvinyl chloride, wherein the content of chlorine in oil in the product is 10 ppm (w/w) or less. A method for reducing chlorine from a plastic mixture comprising polyvinyl chloride using the apparatus of any one of claims 1, 2, 5, and 8 to 10.

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