JP3587018B2 - Treatment method for chlorine-containing resin - Google Patents

Description

【００３６】
【表２】

【００３７】
表１および表２に示されるように、本発明例では塩素含有樹脂と固体熱媒体とともに、これらよりも比重の大きい添加材を供給したことにより、キルン内壁への樹脂残渣の付着を効果的に抑制しつつ、高い脱塩素率で脱塩素処理がなされている。また、脱塩素処理後の樹脂残渣と固体熱媒体および添加材との混合物は、高炉等の燃料や鉄源還元剤用の吹き込み材料として十分に適用可能な性状と品質を有していた。
これに対して添加材を供給しない比較例では、樹脂残渣のキルン内壁への付着率が高く、このため長時間の操業に支障をきたした。
【００３８】
【発明の効果】
以上述べたように本発明の塩素含有樹脂の処理方法によれば、ロータリーキルンを用いた塩素含有樹脂の脱塩素処理において、塩素含有樹脂と固体熱媒体とともに、これらよりも比重の大きい添加材を供給することで、樹脂残渣のキルン内壁への付着を効果的に防止しつつ、高い脱塩素率で塩素含有樹脂の脱塩素処理を行うことができ、このため塩素含有樹脂の効率的な脱塩素処理を長期間安定して実施することができる。
【００３９】
また、請求項３ないし請求項６に係る発明によれば、固体熱媒体および／または添加材として炉の原材料として使用することができる粉粒物等を使用するため、脱塩素処理完了後の樹脂残渣を固体熱媒体や添加材と分離することなく、そのまま高炉等をはじめとする各種の炉（特に溶解炉）に燃料や鉄源還元剤等として供給することができる。また、特に固体熱媒体としてコークスの粉粒物を用いることにより固体熱媒体の偏析等がより効果的に防止され、このため脱塩素処理の高い処理効率を確保することができる。
【００４０】
また、請求項７に係る発明によれば、発生した塩化水素を加熱ガスと混合させることなく取り出すことができるため、排出ガスの処理に要する設備コストや処理コストを従来法に較べて大幅に低減させることができる。また、塩化水素が発生する内管全体を加熱ガスで加熱するため、内管全体の温度を、塩化水素が強い腐食性を示す１５０℃以下の温度域よりも高い温度域に維持することができ、このため発生した塩化水素による装置、特に内管各部の腐食を適切に防止することができる。
【図面の簡単な説明】
【図１】本発明の一実施形態を示す説明図
【図２】図１に示す実施形態におけるロータリーキルンの横断面図
【図３】図１に示す実施形態の具体的な構成例を示す説明図
【図４】本発明の他の実施形態を示す説明図
【図５】図４に示す実施形態におけるロータリーキルンの縦断面図
【図６】図４に示す実施形態におけるロータリーキルンの横断面図
【図７】図４に示す実施形態において用いられるロータリーキルンの他の構造例を示す縦断面図
【図８】図７のロータリーキルンの横断面図
【図９】図４に示す実施形態において用いられるロータリーキルンの他の構造例を示す横断面図
【符号の説明】
１…ロータリーキルン本体、２…耐火物、３…鉄皮、４…通路、５…定量供給装置、６…供給口、７…熱風導管、８…排出装置、９…排出口、１０…排ガス排出口、１１…熱風発生機、１２…駆動モータ、１３…ロータリーキルン本体、１４…外管、１５，１５ａ，１５ｂ，１５ｃ…内管、１６，１７…通路、１８，１９，２０…定量供給装置、２１…排出装置、２２…回収ボックス、２３…排ガス排出口、２４…熱風供給口、２５…排出口、２６…駆動モータ、２７…ガス導管[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a treatment method for dechlorinating a chlorine-containing resin using a rotary kiln.
[0002]
[Prior art]
2. Description of the Related Art In recent years, synthetic resins such as plastics have been rapidly increasing as industrial wastes and general wastes, and their disposal has become a major social problem. Among them, plastics, which are high-molecular hydrocarbon compounds, generate a large amount of heat when they are burned, and when incinerated in a general incinerator, damage the furnace walls, etc., making mass treatment difficult, and most of them are landfills. It is currently dumped on land. However, dumping of plastics and the like is not preferable in terms of environmental measures, and shortage of land for landfill is becoming a social problem in recent years. Therefore, development of a method for mass processing of synthetic resins without dumping has been desired.
[0003]
Against this background, a method of using synthetic resins such as plastics as an auxiliary fuel for a blast furnace or the like and a reducing agent for an iron source is disclosed in, for example, Japanese Patent Publication No. Hei 8-507105 and Japanese Patent Publication No. Sho 51-33493. ing. However, it is said that waste synthetic resin contains about 15% of chlorine-containing resin such as vinyl chloride on average. When such synthetic resin is supplied to a blast furnace or the like, chlorine-containing resin is not contained. A large amount of harmful gas (hydrogen chloride gas) is generated by the thermal decomposition and combustion of the resin, causing significant environmental pollution. Therefore, in order to prevent such a problem, it is necessary to separate a chlorine-containing resin from synthetic resins in advance and remove chlorine (dechlorination treatment) from the chlorine-containing resin.
[0004]
BACKGROUND ART Conventionally, as a method for dechlorinating a chlorine-containing resin, a method is known in which a chlorine-containing resin is heated using a rotary kiln, the resin is thermally decomposed, and chlorine components are eliminated in the form of hydrogen chloride.
However, in this dechlorination method of the rotary kiln method, the resin residue after pyrolysis adheres to the inner wall of the rotary kiln, thereby significantly reducing the dechlorination efficiency, and the resin residue adheres to and grows on the inner wall of the kiln in a short time. There is a problem of being unable to operate.
[0005]
In order to prevent such resin residue from adhering to the inner wall of the rotary kiln, in Japanese Patent Application Laid-Open No. 50-127981, when dechlorination of a chlorine-containing resin is performed by an external heating type rotary kiln, oil is supplied into the kiln in advance. A method has been proposed. However, in many cases, the supplied oil cannot maintain a stable state at the processing temperature, so the supplied oil adheres to the inner wall of the kiln by caulking, reducing the heat transfer area, and desorbing due to a decrease in the heat transfer efficiency from the heated gas. This leads to a decrease in chlorine efficiency. Further, oil stable at the dechlorination temperature is expensive and has a problem in terms of processing cost.
[0006]
On the other hand, Japanese Patent Application Laid-Open No. 7-316339 proposes a method for dechlorination of a chlorine-containing resin in which a chlorine-containing resin and sand as a solid heat medium are supplied into a rotary kiln and a heating gas is supplied into the kiln as a heat source. Have been. In this method, the chlorine-containing resin is heated to about 250 to 350 ° C. while being mixed with the sand by the rotation of the kiln, and this heating causes a desorption reaction in which the chlorine content in the resin is desorbed as hydrogen chloride. Gas is generated. The hydrogen chloride gas is discharged to the outside of the kiln together with the heating gas, and the residue of the chlorine-containing resin that has been subjected to the dechlorination treatment is also discharged to the outside of the kiln together with sand as a solid heat medium.
[0007]
[Problems to be solved by the invention]
However, according to studies by the present inventors, although this conventional technique can suppress adhesion of resin residues to the kiln inner wall to some extent, sand does not function effectively as a heat medium, so that processing efficiency is extremely low. Turns out to be a problem.
Further, when the resin residue after the dechlorination treatment is blown into a melting furnace such as a blast furnace or used as a raw material (mainly, a reducing agent or a fuel for an iron source) or the like, in the above-described conventional technology using sand as a solid heat medium, It is necessary to separate the sand from the resin residue after the dechlorination treatment is completed, and this treatment causes an increase in equipment cost and treatment cost. Further, in many cases, the resin residue and the solid heat medium are fused to each other, so that it is extremely difficult to efficiently separate the resin residue and the heat medium.
[0008]
Accordingly, an object of the present invention is to solve such problems of the prior art, and to adhere resin residues (residue after thermal decomposition of resin, the same applies hereinafter) to the inner wall of the kiln in the dechlorination treatment of chlorine-containing resin by a rotary kiln. An object of the present invention is to provide a method for treating a chlorine-containing resin, which can perform a dechlorination treatment with high treatment efficiency while preventing the occurrence of chlorination.
Another object of the present invention is to provide a chlorine-containing resin that can be directly used as a furnace raw material (fuel or pig source reducing agent, etc.) without separating a solid heat medium from a resin residue after the dechlorination treatment. It is to provide a processing method.
[0009]
[Means for Solving the Problems]
In order to solve these problems, the present inventors studied the effects of the properties of the solid heat medium supplied into the kiln together with the material to be processed on the adhesion of resin residues to the kiln inner wall and the dechlorination efficiency. Was. As a result, in the conventional technology using sand as a solid heat medium, while the effect of suppressing the adhesion of resin residues to the kiln inner wall can be obtained to some extent, sufficient dechlorination efficiency cannot be obtained due to the particle size of the heat medium sand. Because the specific gravity is extremely different from that of the resin material, the sand tends to segregate in the rotary kiln and cannot function effectively as a heat carrier.On the other hand, the segregated sand is interposed between the resin material and the kiln inner wall. It has been found that this is because the adhesion of the resin residue to the inner wall of the kiln is suppressed.
[0010]
From the results of such studies, it has been found that in the method of performing a dechlorination treatment by supplying a solid heat medium together with a chlorine-containing resin into a kiln, the solid heat medium functions as a solid heat medium when segregation occurs in the kiln. On the other hand, the resin residue adheres to the kiln inner wall as described above, and conversely, if the solid heat medium effectively functions as a heat medium without causing segregation in the kiln, the resin residue is deposited on the kiln inner wall. It has been found that the fact that the solid heat medium is easily adhered, that is, the function of the solid heat medium and the effect of suppressing the adhesion of resin residues to the inner wall of the kiln by the solid heat medium are incompatible with each other. As a result of further studies based on such findings, the present inventors have found that a third component (additive material) having a high specific gravity, which is mainly intended to suppress the adhesion of resin residue to the inner wall of the kiln, is to be treated and solid heat. The solid material is supplied into the kiln together with the medium, and this additive is segregated on the kiln inner wall side to minimize the contact between the softened and molten material to be processed and the kiln inner wall. Has been found to be able to effectively prevent the adhesion of the water to the kiln inner wall.
[0011]
Further, from the viewpoint of functionality as an additive and the fact that the resin residue after the dechlorination treatment is used as it is as a furnace raw material without being separated from the additive, as a result of examining materials suitable for the additive, iron ore, sinter It has been found that powdered or crushed materials such as iron scrap are extremely suitable materials as additives. In addition, from the viewpoint of functionality as a solid heating medium and the fact that the resin residue after dechlorination treatment is used as it is as a furnace raw material without being separated from the solid heating medium, a material suitable for the solid heating medium was examined. Sources, iron source reducing agents, powders and granules that can be used as fuels or auxiliary materials, for example, powders such as coke, iron ore, sinter, thermosetting resins, etc. are extremely suitable materials as solid heat carriers. understood.
The present invention has been made based on these findings, and the features are as follows.
[0012]
[1] A material from which chlorine-containing resin is to be treated and supplied to a rotary kiln together with a solid heat medium and heated to thermally decompose the chlorine-containing resin to release the chlorine content in the resin as hydrogen chloride and remove the chlorine. In a method for recovering a residue, a chlorine-containing resin and / or a crushed material of a substance having a specific gravity larger than that of a solid heat medium are supplied together with a material to be treated and a solid heat medium as an additive. Treatment method for contained resin.
[2] The method for treating a chlorine-containing resin according to the above-mentioned [1], wherein the material to be treated comprises only a chlorine-containing resin.
[0013]
[3] The processing method according to the above [1] or [2], wherein the additive material is at least one kind of powder and / or crushed material selected from iron ore, sintered ore, and iron scrap. For treating chlorine-containing resin.
[4] In the treatment method of the above [1] or [2], the solid heat medium is one or more powders selected from powders and granules usable as an iron source, an iron source reducing agent, a fuel or an auxiliary material of a furnace. One or more powdered and / or crushed materials selected from iron ore, sinter, and iron scrap, which have a higher specific gravity than the chlorine-containing resin and the solid heating medium. A method for treating a chlorine-containing resin, comprising a powder and / or a crushed material.
[5] The chlorine-containing method according to the above [4], wherein the solid heat medium comprises at least one powdery material selected from coke, iron ore, sintered ore, and thermosetting resin. Resin treatment method.
[0014]
[6] The method for treating a chlorine-containing resin according to the above-mentioned [4], wherein the solid heating medium comprises at least one powdery material selected from coke and a thermosetting resin.
[7] In the processing method according to any one of the above [1] to [6], the rotary kiln main body includes an outer tube and an inner tube disposed therein, and the inner tube serves as a passage for a material to be processed. Using a rotary kiln having a space between the inner tube and the outer tube as a heating gas passage, supplying the material to be treated containing the chlorine-containing resin, the solid heat medium, and the additive to the passage for the material to be treated, and heating the passage for the heating gas. A method for treating a chlorine-containing resin, comprising supplying a gas to heat a material to be treated in a passage for the material to be treated.
In the present invention, the material to be treated does not prevent inclusion of resins other than the chlorine-containing resin, composite materials of the chlorine-containing resin and other materials, and materials other than the resin.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
1 and 2 show one embodiment of the present invention. In the figure, reference numeral 1 denotes a rotary kiln main body. The rotary kiln main body 1 includes a refractory 2 and a steel shell 3, and the inside of the rotary kiln main body 1 constitutes a passage 4 for carrying out a dechlorination treatment while transferring a material to be treated. The passage 4 of the rotary kiln main body 1 is supplied with a material to be processed, which is partially or entirely a chlorine-containing resin, and a solid heat medium from one end thereof, and a heating gas as a heat source. This heating gas heats the entire kiln and also heats the material to be processed and the solid heating medium. In addition, the solid heat medium not only heats the material to be treated, but also disperses in the material to be treated, thereby suppressing fusion and clumping of the material to be treated, thereby improving the dechlorination efficiency. The material to be treated is heated while being mixed with the solid heat medium by the rotation of the kiln, and the thermal decomposition of the chlorine-containing resin by this heating causes the chlorine content in the resin to be desorbed as hydrogen chloride, generating hydrogen chloride gas.
[0016]
In the present invention, in such a desalination treatment, a chlorine-containing resin and an additive are used together with a material to be treated (when the material to be treated is substantially composed of only a chlorine-containing resin, a chlorine-containing resin material) and a solid heat medium. A powder and / or a crushed material of a substance having a higher specific gravity than the solid heat medium is supplied. As a result, during the dechlorination treatment by the rotary kiln, the chlorine-containing resin and the additive having a higher specific gravity than the solid heat medium segregate on the kiln inner wall side, and are always interposed between the material to be treated and the kiln inner wall. Adhering of the residue to the inner wall of the kiln is effectively suppressed. In addition, the solid heat medium only needs to exhibit its original function. Therefore, a high dechlorination efficiency can be obtained by using a solid heat medium made of a material that does not cause segregation.
[0017]
As an additive, from the viewpoint that the functionality and the residue of the dechlorinated resin are supplied to a furnace such as a blast furnace (particularly, a melting furnace) without being separated from the additive, iron ore, sintered ore, Granules or crushed materials such as iron scrap are suitable, and it is preferable to use one or more selected from these.
The supply amount of the additive may be appropriately determined according to the supply amounts of the material to be treated and the solid heating medium. The mixture of the material to be treated and the solid heat medium and the kiln inner wall are present (segregated) in the area in contact with the inner wall, that is, the entire lower region of the rotating kiln inner surface as shown in FIG. Therefore, it is preferable that the supply amount is set so as to be distributed over such an area.
[0018]
In addition, as a solid heating medium supplied into the kiln together with the material to be treated, the functionality that segregation in the kiln is unlikely to occur, and the resin residue after dechlorination is not separated from the solid heating medium as it is From the viewpoint of supply to furnaces such as blast furnaces (especially melting furnaces), those that can be used as raw materials for furnaces, that is, granules that can be used as iron sources, iron source reducing agents, fuels, auxiliary materials, etc. for furnaces It is preferable to use Thus, the residue of the resin material after the dechlorination treatment can be supplied as it is to the melting furnace or the like as a reducing agent or fuel for the iron source without being separated from the solid heating medium. Examples of powders suitable for such a heat medium include powders such as coke, iron ore, sinter, and thermosetting resins (for example, phenolic resins, urea resins, etc.). The above can be used as a solid heat medium. Also, in order to prevent segregation of the solid heat medium in the kiln and improve the heating efficiency of the material to be treated, it is preferable that the specific gravity of the heat medium is as close as possible to that of the resin material. It is most preferable to use coke or a thermosetting resin powder as a medium.
[0019]
Therefore, in the method of the present invention, as a solid heat medium, powders and granules (eg, coke, iron ore, sintered powder, thermosetting resin, etc.) usable as a furnace iron source, iron source reducing agent, fuel, auxiliary material, etc. De-chlorinated resin by using at least one type of powder and / or crushed material such as iron ore, sintered ore, iron scrap, etc. The material residue can be supplied as it is to the melting furnace or the like as a reducing agent or fuel for the iron source without being separated from the heat medium and the additive.
In the above description, the same type of material (for example, iron ore, sintered ore) is given as the powdery material suitable for the solid heating medium and the powdery material suitable for the additive. The specific gravity of the solid heat medium and the additive used is on the condition that the heat medium is smaller than the additive. Therefore, a combination of the solid heat medium and the additive may be selected according to this condition.
[0020]
The heating temperature of the material to be treated in the kiln (in the passage 4 in the present embodiment) is preferably from 250 to 350 ° C, more preferably around 300 ° C. If the heating temperature is lower than 250 ° C., the elimination reaction of hydrogen chloride is not efficiently performed, while if it exceeds 350 ° C., thermal decomposition of the resin material into gaseous and liquid hydrocarbons starts to occur.
The heated gas flowing through the passage 4 and the hydrogen chloride gas desorbed from the material to be treated are discharged from the other end of the passage 4, and the hydrogen chloride gas in the discharged gas is collected in a hydrogen chloride absorption building or the like. Further, the material to be treated (mainly the resin residue after thermal decomposition) after the dechlorination treatment is discharged out of the kiln together with the solid heat medium and the additive.
[0021]
FIG. 3 shows a more specific configuration example of the system shown in FIGS. 1 and 2. A fixed-quantity supply device 5 for material supply having a supply port 6 is provided at one end of a rotary kiln body 1 having a passage 4. (Screw feeder) and a hot air conduit 7 for supplying a heating gas (hot air) are connected. Further, on the other end side of the rotary kiln body 1, a discharge device 8 for discharging the treated material (resin residue + solid heat medium + additive material) and exhaust gas is provided. The discharge device 8 has a treated material discharge port 9 at a lower portion thereof and an exhaust gas discharge port 10 at an upper portion thereof. In the drawings, reference numeral 11 denotes a hot air generator, and reference numeral 12 denotes a drive motor of the fixed quantity supply device 5.
[0022]
According to such a rotary kiln, the material to be treated, the solid heating medium, and the additive are supplied into the passage 4 from one end of the rotary kiln body 1 through the fixed amount supply device 5, and the heating gas is supplied from the hot air conduit 7. .
In the passage 4, the chlorine-containing resin contained in the material to be treated is dechlorinated as described above, and the exhaust gas (heating gas + hydrogen chloride gas), the residue of the resin material to be treated which has been dechlorinated, the solid heat The mixture of the medium and the additive is discharged to the discharge device 8 at the other end of the rotary kiln main body 1, and the exhaust gas is discharged from the upper exhaust gas discharge port 10 and mixed with the residue of the resin material to be treated, the solid heat medium and the additive. The body is discharged from the lower outlet 9 respectively.
[0023]
The material to be treated, the solid heat medium, and the additive may be supplied to the rotary kiln main body 1 by using separate supply devices.
FIGS. 4 to 6, FIGS. 7, 8 and 9 show embodiments using a rotary kiln of an external heating system, each of which comprises a rotary kiln body having an outer tube and an inner tube disposed therein. A rotary kiln is used in which the inside of the inner tube is used as a passage for the material to be treated and the space between the inner tube and the outer tube is used as a passage for the heating gas.
[0024]
In a dechlorination treatment using a single-tube rotary kiln (a rotary kiln body having a single-tube furnace) as shown in FIGS. 1 and 2, the generated hydrogen chloride is discharged outside the furnace in a state mixed with a heating gas. Moreover, since the amount of the exhaust gas is enormous, a large-scale facility for separating and removing hydrogen chloride from the exhaust gas is required. In addition, hydrogen chloride has a characteristic of exhibiting high corrosiveness even in a temperature range of 150 ° C. or less, in addition to a high temperature range of more than 350 ° C. In a single-pipe rotary kiln as shown in FIGS. 1 and 2, the temperature of the inner wall of the refractory constituting the furnace wall is substantially equal to the processing temperature, but the outside of the furnace wall is at room temperature, so A temperature gradient is generated in the thickness direction of the refractory, and the dew point (150 ° C.) or less near the inner surface of the refractory is reduced. Therefore, there is a possibility that the refractory may be corroded by hydrogen chloride penetrating inside the refractory.
[0025]
On the other hand, in a rotary kiln having a structure as shown in FIGS. 4 to 9, the generated hydrogen chloride gas can be taken out without being mixed with the heating gas, so that the equipment cost and the processing cost required for the treatment of the exhaust gas are reduced. It can be greatly reduced compared to a single-pipe rotary kiln. In addition, since the entire inner tube in which hydrogen chloride gas is generated is heated by the heating gas, the temperature of the entire inner tube is maintained at a higher temperature range than a temperature range of 150 ° C. or less, at which hydrogen chloride exhibits strong corrosiveness. Therefore, it is possible to appropriately prevent corrosion of the apparatus, particularly each part of the inner pipe, by the generated hydrogen chloride gas.
[0026]
First, in the rotary kiln shown in FIGS. 4 to 6, 13 is a rotary kiln main body, 14 is an outer tube constituting the same, and 15 is an inner tube. It is arranged substantially concentrically with the tube 14. The inside of the inner tube 15 forms a passage 16 (processing space) for the material to be processed, and the space between the outer tube 14 and the inner tube 15 forms a passage 17 for the heating gas.
[0027]
One end of the inner tube 15 forming the passage 16 extends outward from the outer tube 14, and one end of the inner tube is connected to a fixed-quantity supply device 18, 19, 20 (such as a screw feeder) for material supply. The other end of the inner pipe 15 is connected to a treated material and exhaust gas discharging device 21. The discharge device 21 has a treated material collection box 22 at its lower part and an exhaust gas discharge port 23 at its upper part. Further, a hot air supply port 24 for supplying a heating gas (hot air) is provided at one end of the outer tube 14 that forms the passage 17 with the inner tube 15, and a heating gas supply port 24 is provided at the other end. Discharge ports 25 are provided respectively. In the other drawings, reference numeral 26 denotes a drive motor of each fixed-rate supply device.
[0028]
FIGS. 7 and 8 show another configuration example in which the configuration of the inner tube and the like is different. In FIGS. 4 to 6, a single inner tube is arranged in the outer tube. 14 is provided with a plurality of inner tubes 15a to 15c. In addition, the number of the inner tubes 15 arranged in the outer tube 14 is arbitrary.
In such a structure, since a plurality of inner tubes are provided, the heat transfer area increases accordingly. Therefore, there is an advantage that heat can be efficiently transferred from the heating gas flowing through the passage 17 into the inner tubes. The mixing ratio and type of the treatment material and the solid heat medium or the additive material can be changed for each inner tube.
FIG. 9 shows another configuration example, in which a gas conduit 27 is arranged inside the inner pipe 15 so that the heating efficiency of the material to be processed can be further increased. Note that such a gas conduit can also be arranged in the inner pipes 15a to 15c of the apparatus shown in FIGS.
[0029]
In the rotary kiln of FIGS. 4 to 9 described above, the dechlorination of the material to be processed can be performed without any trouble as long as the inner pipes 15, 15a to 15c rotate substantially in the circumferential direction. Therefore, in each of the rotary kilns described above, the entire rotary kiln body 13 including the outer pipe 14 may be configured to be rotatable in the circumferential direction, but only the inner pipe 15 is rotatable in the circumferential direction as shown in FIG. May be configured. In the case of the rotary kilns of FIGS. 7 and 8, the inner tubes 15a to 15c are integrally rotated (in this case, the individual inner tubes are eccentrically rotated as in the case of rotating the rotary kiln body 13). Alternatively, the inner tubes 15a to 15c may be individually rotated.
[0030]
In the rotary kiln shown in FIGS. 4 to 9, the material to be treated, the solid heat medium and the additive are supplied into the passage 16 through the quantitative supply devices 18, 19, and 20 or any of these, and the hot air A heating gas is supplied into the passage 17 from the conduit 24.
The heating gas supplied to the passage 17 heats the entire inner pipes 15, 15a to 15c, and the material to be processed is heated through the pipe walls. The heated gas flowing through the passage 17 is discharged from the discharge port 25.
[0031]
On the other hand, the material to be processed, the solid heat medium, and the additive supplied to the passage 16 inside the inner tubes 15, 15a to 15c are mixed with the material to be processed and the solid heat medium by rotation of the inner tubes 15, 15a to 15c ( The additive material is segregated on the inner wall side of the kiln as shown in FIG. 2) and heated while being transported in the passage 16, whereby the chlorine content in the chlorine-containing resin contained in the material to be treated is desorbed as hydrogen chloride, Hydrogen chloride gas is generated. The exhaust gas containing the hydrogen chloride gas, the resin residue after the dechlorination treatment, the solid heating medium, and the additive are discharged to the discharge device 21, of which the exhaust gas is discharged from the upper exhaust gas discharge port 23, and the resin residue, the solid The heat medium and the additive are collected in the collection box 22 through the lower outlet. Therefore, the hydrogen chloride gas generated by heating the chlorine-containing resin is recovered without mixing with the heating gas flowing through the passage 17.
[0032]
Note that a small amount of carrier gas (such as air) can be passed through the passage 16 in order to smoothly move the material to be processed within the passage 16.
In the rotary kiln described above, the heating gas flows outside the inner pipes 15, 15a to 15c in which hydrogen chloride is generated, and therefore the entire inner pipe is at the above-mentioned temperature of about 250 to 350 ° C. There is no temperature region of 150 ° C. or less where the corrosion action by hydrogen chloride is large in the contact portion. Therefore, corrosion of the furnace wall and the like by the hydrogen chloride gas, particularly corrosion of each part of the inner tube, is appropriately prevented.
In each of the embodiments shown in FIGS. 1 to 9, the transfer direction of the processing target material and the like and the supply direction of the heating gas (the gas flow direction) are the same, but the heating gas supply direction (the gas flow direction). ) Can be reversed in the direction of transfer of the material to be treated (gas countercurrent method), thereby enabling more efficient heating of the material to be treated.
[0033]
【Example】
Using a rotary kiln shown in FIGS. 4 to 6, a chlorine-containing resin having a chlorine content of 43% by weight was dechlorinated. In the present example, coke breeze was used as the solid heat carrier, and the iron ore powder having a specific gravity larger than the chlorine-containing resin and coke breeze was used as the additive (bulk specific gravity: 4200 kg / m2). ³ , Particle size: 4 to 8 mm). Also, a small amount of inert gas (carrier gas) was passed through the passage 16 for the material to be treated in the rotary kiln body 13. The results are shown in Tables 1 and 2 together with the supply conditions and processing conditions of the material to be processed.
The configuration of the rotary kiln is as follows.
Inner tube inner diameter: 150mmφ × 1500mmL
Inner diameter of outer tube: 450mmφ × 1200mmL
Inclination angle of the entire device: 2 °
Kiln rotation speed: 4 rpm
[0034]
The dechlorination rate, decomposition rate and resin residue adhesion rate were determined by the following equations.
Dechlorination rate = {(amount of chlorine in resin residue) / (amount of chlorine in supplied chlorine-containing resin)} × 100
Decomposition rate = {1- (amount of combustibles other than chlorine in resin residue) / (amount of combustibles other than chlorine in supplied chlorine-containing resin)} × 100
Resin residue adhesion rate = {(resin residue adhesion amount on kiln inner wall) / (processed material supply amount + solid heating medium supply amount + additive material supply amount)} × 100
[0035]
[Table 1]

[0036]
[Table 2]

[0037]
As shown in Tables 1 and 2, in the present invention examples, the addition of the chlorine-containing resin and the solid heat medium together with the additive having a higher specific gravity than these materials effectively prevented the resin residue from adhering to the kiln inner wall. Dechlorination is performed at a high dechlorination rate while controlling. In addition, the mixture of the resin residue after the dechlorination treatment, the solid heating medium, and the additive had properties and quality that could be sufficiently applied as a fuel for a blast furnace or the like and a blowing material for an iron source reducing agent.
On the other hand, in the comparative example in which the additive was not supplied, the adhesion rate of the resin residue to the inner wall of the kiln was high, which hindered long-term operation.
[0038]
【The invention's effect】
As described above, according to the method for treating a chlorine-containing resin of the present invention, in the dechlorination treatment of the chlorine-containing resin using a rotary kiln, together with the chlorine-containing resin and the solid heat medium, an additive having a higher specific gravity than these is supplied. By doing so, the chlorine-containing resin can be dechlorinated at a high dechlorination rate while effectively preventing the resin residue from adhering to the kiln inner wall. Can be stably performed for a long period of time.
[0039]
According to the third to sixth aspects of the present invention, since the solid heating medium and / or powder or the like that can be used as a raw material of the furnace is used as the additive, the resin after the completion of the dechlorination treatment is used. The residue can be directly supplied as a fuel or an iron source reducing agent to various furnaces such as a blast furnace (particularly, a melting furnace) without being separated from a solid heating medium or an additive. Further, in particular, by using coke powder as the solid heat medium, segregation of the solid heat medium and the like can be more effectively prevented, and therefore, high treatment efficiency of the dechlorination treatment can be secured.
[0040]
Further, according to the invention of claim 7, since the generated hydrogen chloride can be taken out without being mixed with the heating gas, the equipment cost and the processing cost required for the treatment of the exhaust gas are significantly reduced as compared with the conventional method. Can be done. In addition, since the entire inner tube in which hydrogen chloride is generated is heated by the heating gas, the temperature of the entire inner tube can be maintained at a higher temperature range than a temperature range of 150 ° C. or less where hydrogen chloride exhibits strong corrosiveness. Therefore, it is possible to appropriately prevent corrosion of the apparatus, particularly each part of the inner pipe, by the generated hydrogen chloride.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view of the rotary kiln in the embodiment shown in FIG.
FIG. 3 is an explanatory diagram showing a specific configuration example of the embodiment shown in FIG. 1;
FIG. 4 is an explanatory view showing another embodiment of the present invention.
FIG. 5 is a longitudinal sectional view of the rotary kiln in the embodiment shown in FIG.
FIG. 6 is a cross-sectional view of the rotary kiln in the embodiment shown in FIG.
FIG. 7 is a longitudinal sectional view showing another example of the structure of the rotary kiln used in the embodiment shown in FIG.
FIG. 8 is a cross-sectional view of the rotary kiln of FIG. 7;
FIG. 9 is a cross-sectional view showing another structural example of the rotary kiln used in the embodiment shown in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Rotary kiln main body, 2 ... Refractory, 3 ... Steel, 4 ... Pathway, 5 ... Quantitative supply device, 6 ... Supply port, 7 ... Hot air conduit, 8 ... Discharge device, 9 ... Discharge port, 10 ... Exhaust gas discharge port , 11: Hot air generator, 12: Drive motor, 13: Rotary kiln body, 14: Outer tube, 15, 15a, 15b, 15c: Inner tube, 16, 17: Passage, 18, 19, 20: Fixed amount supply device, 21 ... Exhaust device, 22 ... Recovery box, 23 ... Exhaust gas exhaust port, 24 ... Hot air supply port, 25 ... Exhaust port, 26 ... Drive motor, 27 ... Gas conduit

Claims (7)

The material to be treated containing chlorine-containing resin is supplied to a rotary kiln together with a solid heating medium and heated, and the chlorine-containing resin is thermally decomposed to release the chlorine content in the resin as hydrogen chloride, and the resin residue from which chlorine has been removed is recovered. In the method, a powder and / or a crushed material of a substance having a specific gravity larger than that of the chlorine-containing resin and the solid heat medium are supplied as an additive together with the material to be treated and the solid heat medium. Processing method. 2. The method for treating a chlorine-containing resin according to claim 1, wherein the material to be treated comprises only a chlorine-containing resin. The method for treating a chlorine-containing resin according to claim 1 or 2, wherein the additive material is at least one kind of powder and / or crushed material selected from iron ore, sintered ore, and iron scrap. . The solid heating medium is composed of one or more types of powders selected from iron sources of the furnace, iron source reducing agents, fuels or powders that can be used as auxiliary materials, and the additive is iron ore, sinter, or iron. At least one kind of powder and / or crushed material selected from scrap, wherein the powder and / or crushed material has a higher specific gravity than the chlorine-containing resin and the solid heat medium. Item 3. The method for treating a chlorine-containing resin according to Item 1 or 2. The method for treating a chlorine-containing resin according to claim 4, wherein the solid heat medium is made of at least one powdery substance selected from coke, iron ore, sinter, and thermosetting resin. The method for treating a chlorine-containing resin according to claim 4, wherein the solid heat medium comprises at least one powdery substance selected from coke and a thermosetting resin. The rotary kiln body is composed of an outer tube and an inner tube disposed therein, wherein the inner tube is used as a passage for a material to be treated, and the space between the inner tube and the outer tube is used as a passage for a heating gas. To supply the material to be treated containing the chlorine-containing resin, the solid heat medium and the additive to the treatment material passage, and to supply the heating gas to the heating gas passage to heat the treatment material in the treatment material passage. The method for treating a chlorine-containing resin according to claim 1, 2, 3, 4, 5, or 6.

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