JPH10216674A - Treatment of chlorine-containing plastic waste and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable discharging of an incineration discharge gas into air by subjecting a chlorine-contg. plastic waste to dry distillation, absorbing the hydrogen chloride gas produced by the dry distillation to water to collect, and incinerating the carbon residue after the dry distillation. SOLUTION: A waste of polyvinyl chloride products is put in a furnace 2 for dry distillation and incineration, then a boiler 6 and a heating furnace 8 are operated to produce an overheated vapor, which is supplied to the furnace 2 to dry distillate the waste. The discharged gas containing the overheated vapor, the gas produced by dry distillation and hydrogen chloride gas produced by dry distillation is sent through a gas cooling device 14, a hydrogen chloride concentration meter 6 and a switching valve 15 to a collecting device 3 for hydrogen chloride, where the discharged gas is successively introduced to bubble in three water tanks 16 to 18. Thereby, the overheated vapor in the discharged gas is condensed into water and recovered. The hydrogen chloride gas is absorbed by the water while the gas produced by dry distillation is passed through the water tank 18 and then supplied by a blower 24 to a burner of the heating furnace 8 with air for combustion. Thus, the gas produced by dry distillation is rendered harmless.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for efficiently treating a chlorine-containing plastic waste such as polyvinyl chloride and polyvinylidene chloride, and a treatment apparatus for carrying out the method.

[0002] In this specification, the term "chlorine-containing plastic waste" refers to not only waste consisting of chlorine-containing plastic but also waste of a composite material or a product thereof at least partially composed of chlorine-containing plastic. Shall mean.

[0003]

2. Description of the Related Art Waste of chlorine-containing plastics has been conventionally disposed of in landfills when incinerated as it produces a large amount of hydrogen chloride gas and harmful dioxins.

[0004]

However, it is becoming increasingly difficult to secure landfill sites, and new treatment measures are required.

An object of the present invention is to provide a method for treating chlorine-containing plastics which can meet the above-mentioned demands, and a treatment apparatus for performing the method.

[0006]

According to the present invention, there is provided a method for treating chlorine-containing plastic waste, which comprises subjecting chlorine-containing plastic waste to dry distillation, absorbing and collecting hydrogen chloride gas generated by the dry distillation, and subjecting the waste to carbonization. After the completion, the carbon residue is incinerated.

In this method, superheated steam is preferably used as a heat source for carbonization of chlorine-containing plastic waste,
The superheated steam after the carbonization is cooled and recovered as condensed water in a hydrogen chloride recovery step.

[0008] The carbonized gas generated by carbonization can also be used as an auxiliary fuel for generating a carbonization heat source after recovering hydrogen chloride.

Preferably, the concentration of hydrogen chloride is measured between the carbonization step and the hydrogen chloride recovery step, and the carbonization residue is incinerated after confirming the completion of carbonization based on the measured values.

The following apparatus is used to carry out the method for treating chlorine-containing plastic waste according to the present invention.

That is, a carbonization / incinerator for carbonizing chlorine-containing plastic waste and incinerating carbon residues after carbonization, and a hydrogen chloride recovery system for absorbing hydrogen chloride gas generated by carbonization in the carbonization / incineration furnace into water. An apparatus for treating chlorine-containing plastic waste, comprising an apparatus.

The apparatus having the above configuration preferably includes a superheated steam generator for generating superheated steam for dry distillation and sending it to the incinerator. Further, the apparatus having the above configuration preferably includes a line for sending the carbonized gas generated by carbonization and passing through the hydrogen chloride recovery device to the superheated steam generator.

[0013] A hydrogen chloride concentration meter is preferably provided between the dry distillation and incinerator and the hydrogen chloride recovery device.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an apparatus for treating chlorine-containing plastic waste according to the present invention will be described with reference to the drawings.

An apparatus for treating chlorine-containing plastic waste according to the present invention comprises a superheated steam generator (1) for generating superheated steam for dry distillation, and a chlorine-containing plastic waste disposed by superheated steam coming from the superheated steam generator (1). A carbonization and incinerator that carbonizes materials and incinerates carbon residues after carbonization.
(2), a hydrogen chloride recovery unit (3) that absorbs hydrogen chloride gas generated by dry distillation in the carbonization and incinerator (2), and a hydrogen chloride recovery unit (3) generated by dry distillation and passed through A line (4) for supplying the carbonized gas to the superheated steam generator (1),
It mainly consists of a hydrogen chloride concentration meter (5) installed between the carbonization and incinerator (2) and the hydrogen chloride recovery unit (3).

The superheated steam generator (1) comprises a boiler (6) and
A heating furnace (8) for heating steam coming from the boiler (6) through the steam valve (7) to generate superheated steam. heating furnace
Fuel is supplied to the burner (9) of (8) through a fuel valve (10), and combustion air is supplied by a blower (24) through an air valve (21).

The carbonization and incinerator (2) has a vertically long drum shape, has a lid (11) on the top, has a burner (12) on one side of the bottom, and has a grate (13) near the lower end inside. )have. Fuel is supplied to the burner (12) via a fuel valve (23),
By (24), combustion air is supplied via an air valve (22). The superheated steam coming from the heating furnace (8) is injected and supplied from the peripheral wall toward the center into the carbonization and incinerator (2) at a level above the grate (13). The carbonization and incinerator (2) is provided with a temperature controller (24) for measuring and controlling the internal temperature.

A gas cooling device is provided downstream of the dry distillation and incinerator (2).
(14), a hydrogen chloride concentration meter (5), a switching valve (15), and a hydrogen chloride recovery device (3) are provided in this order.

The hydrogen chloride recovery unit (3) comprises three water tanks (16)
The gas coming from the gas cooling device (14) consisting of (17) and (18) is sequentially bubbled in each tank. Cooling water circulating through the gas cooling device (14) and the three water tanks (16), (17), (18) is circulated by a pump (19) through a cooling tower (20).

The line (4) is connected to a heating furnace through an air valve (21) by a blower (24).
Send it to the burner (9) in (8).

The dry distillation and incinerator (2) is provided with a temperature control device (24) for measuring and controlling the internal temperature.

In the apparatus for treating chlorine-containing plastic waste having the above-mentioned structure, first, the waste of polyvinyl chloride product is put into the carbonization and incinerator (2). Then boiler (6)
And a superheating furnace (8) to operate to generate superheated steam, which is injected and supplied to a carbonization and incineration furnace (2) to obtain a predetermined furnace temperature (400 ° C to 6 ° C).
(00 ° C.) for a predetermined time (30 minutes to 2 hours). This temperature control uses a temperature control device (2
This is performed by automatically adjusting the degree of opening of the steam valve (7), fuel valve (10) and air valve (21) of the superheated steam generator (1) based on the temperature measured by 4).

Exhaust gas containing the superheated steam used for the carbonization, the carbonization gas generated by the carbonization, and the hydrogen chloride gas generated by the carbonization was discharged from the top of the carbonization and incinerator (2) to a gas cooling device (14). It is sent to the hydrogen chloride recovery unit (3) via the hydrogen concentration meter (5) and the switching valve (15), and is sequentially bubbled into the water in the three water tanks (16), (17) and (18) of the unit (3) . The superheated steam in the exhaust gas is cooled by bubbling in three water tanks (16), (17), and (18) after passing through the gas cooling device (14), and is recovered as water in the water tank as condensed water. Hydrogen chloride gas is absorbed by water by bubbling in three water tanks (16), (17) and (18). The carbonization gas is not absorbed by water when bubbling in water tanks (16), (17) and (18). The dry distillation gas passed through the final water tank (18) is supplied to the burner (9) of the heating furnace (8) together with the combustion air via the valve (21) by the blower (24) by the line (4),
At the same time as using it as an auxiliary fuel for the burner (9), the carbonized gas is made harmless.

The concentration of hydrogen chloride in the exhaust gas discharged from the carbonization and incinerator (2) is measured by a hydrogen chloride concentration meter downstream of the gas cooling device (14).
After confirming that hydrogen chloride gas is no longer generated and dry distillation is completed, set the switching valve (15) to the exhaust side.
(B) is switched manually or automatically, and the steam valve (7), fuel valve (10) and air valve (10) of the superheated steam generator (1) are all closed. ) Open the fuel valve (23) and air valve (22). Next, superheated steam generator (1)
The burner (12) is ignited and the furnace temperature is raised to a predetermined temperature (800 ° C).
And the carbon residue remaining on the grate (13) is incinerated. This temperature control is based on the temperature measured by the temperature controller (24).
This is performed by automatically adjusting the opening degree of the fuel valve (23) and the air valve (22) in (2). In this way, each valve is switched from the carbonization mode (A) to the incineration mode (B), and the carbon residue is completely incinerated. As a result, the carbon residue is completely dechlorinated. Further, since the generated incineration gas does not contain hydrogen chloride gas, the gas can be released to the atmosphere as it is.

[0025]

The effects of the present invention are as follows.

1) Since carbon-containing plastic waste is carbonized, and hydrogen chloride gas generated by carbonization is absorbed in water and collected, the incineration exhaust gas of carbon residue after carbonization does not contain hydrogen chloride gas. Therefore, the incineration exhaust gas can be directly discharged into the atmosphere.

2) Since the carbonization and the subsequent incineration can be performed in one furnace, the construction cost of the apparatus can be reduced.

3) In the method using superheated steam as a heat source for dry distillation, the amount of exhaust gas to be treated can be greatly reduced by cooling and condensing the superheated steam after dry distillation to recover it.

4) In the method of sending the carbonized gas to the superheated steam generator, the carbonized gas can be used as an auxiliary fuel for the device to save fuel and achieve the combustion detoxification treatment of the carbonized gas.

[Brief description of the drawings]

FIG. 1 is a pipe system diagram showing an embodiment of the present invention.

[Explanation of symbols]

 1: Superheated steam generator 2: Dry distillation and incinerator 3: Hydrogen chloride recovery device 4: Line 5: Hydrogen chloride concentration meter

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI F23J 15/02 F23J 15/00 C (72) Inventor Yoshitoshi Sekiguchi 5-28 Nishikujo, Konohana-ku, Osaka Hitachi Zosen Corporation (72) Inventor Kunio Sasaki 5-3-28 Nishikujo, Konohana-ku, Osaka-shi Within Hitachi Zosen Corporation (72) Inventor Kenji Nishiyama 5-3-28 Nishikujo, Konohana-ku, Osaka-shi Within Hitachi Zosen Corporation ( 72) Inventor Takusen Ito 8916-12 Takayama-cho, Ikoma City, Nara Prefecture Science Plaza 3F, Kwanai Gakuto City Inside Keihanna Environment Co., Ltd. 3F Keihanna Environment Co., Ltd. (72) Inventor: Osamu Onishi 1-4-2 Nakamichi, Higashinari-ku, Osaka City Osaka Gas Engineering Co., Ltd. Within the company (72) inventor Morimoto tertiary Osaka Higashinari-ku, centrist 1-chome No. 4 No. 2 Osaka Gas Engineering Co., Ltd. in

Claims (8)

[Claims] Claims 1. A chlorine-containing plastic waste is carbonized,
A method for treating chlorine-containing plastic waste in which hydrogen chloride gas generated during carbonization is absorbed by water and collected, and carbon residues are incinerated after carbonization. 2. The method according to claim 1, wherein superheated steam is used as a heat source for dry distillation of chlorine-containing plastic waste, and the superheated steam after dry distillation is cooled and recovered as condensed water in a hydrogen chloride recovery step. 3. The method according to claim 1, wherein the carbonization gas generated by carbonization is used as an auxiliary fuel for generating a carbonization heat source after recovering hydrogen chloride. 4. The method according to claim 1, wherein the concentration of hydrogen chloride is measured between the carbonization step and the hydrogen chloride recovery step, and the carbonization residue is incinerated after confirming the completion of carbonization based on the measured value. The described method. 5. A carbonization and incinerator for carbonizing chlorine-containing plastic waste and incinerating carbon residues after carbonization, and hydrogen chloride recovery for absorbing hydrogen chloride gas generated by carbonization in the carbonization and incinerator in water. An apparatus for treating chlorine-containing plastic waste, comprising an apparatus. 6. The apparatus according to claim 5, further comprising a superheated steam generator that generates superheated steam for carbonization and sends it to the carbonization and incinerator. 7. The apparatus according to claim 6, further comprising a line for sending the carbonized gas generated by carbonization and passing through the hydrogen chloride recovery device to a superheated steam generator. 8. A hydrogen chloride concentration meter is provided between the dry distillation and incinerator and the hydrogen chloride recovery device.
Item.