JPH09239343A - Synthetic resins treatment and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of harmful gas in a method of treating synthetic resins using hydrochloric acid recovery equipment for recovering hydrochloric acid by taking out hydrogen chloride generated by combustion of chlorine containing high molecular resin to outside an incinerator together with gaseous hydrochloric acid generated by thermal decomposition of hydrochloric acid-based waste liquid to recover it as hydrochloric acid. SOLUTION: A synthetic resin material crushed by a crusher 8 is fed into a incinerator 1 by feeding means 9, and also pickling waste water is fed into the incinerator 1 though a feeding means 4. And combustion gas such as blast furnace gas and blast furnace gas plus coke oven gas is fed into the roaster 1 through a feeding means 5, and furthermore, oxygen containing gas is fed into the roaster 1 through a feeding means 6. By combustion of the fuel gas, the pickling waste water is thermally decomposed into gaseous hydrochloric acid and iron oxide. The iron oxide formed by the thermal decomposition is taken out from the incinerator bottom part to recover it as that suitable for ferrite material. On the other hand, after the gaseous hydrochloric acid is taken out the incinerator top part and becomes rid of dust by a dust collector 2, it is recovered as an aqueous solution of hydrogen chloride of high concentration by an absorber 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to synthetic resins (mainly synthetic resins) utilizing a hydrochloric acid recovery facility for recovering hydrochloric acid by treating a hydrochloric acid waste liquid discharged from a steel material pickling facility or the like. (Waste) treatment method and equipment provided for its implementation.

[0002]

2. Description of the Related Art In recent years, synthetic resins such as plastics have rapidly increased as industrial wastes and general wastes, and their disposal has become a major problem. Among these, plastics, which are high-molecular hydrocarbon compounds, generate a large amount of heat during combustion, and when incinerated, damage to the incinerator makes mass treatment difficult, and most of them are dumped in landfills. That is the current situation. However, the dumping of plastics and the like is not preferable in terms of environmental measures, and recently, the shortage of land for landfill is becoming a social problem. Therefore, the development of a large-scale processing method of synthetic resins that does not rely on dumping has been earnestly desired. .
Against this background, a technique of pulverizing waste synthetic resins and using them as auxiliary fuel for blast furnaces and the like is disclosed in European Patent Publication No. 0622465A1 and Japanese Patent Publication No. 51-3349.
No. 3 discloses this.

[0003]

However, it is said that chlorine-containing polymer resins such as vinyl chloride resins are contained in the synthetic resins as wastes in an amount of about 15% on average. When synthetic resins are used as an auxiliary fuel for a blast furnace or the like, a large amount of harmful gas (HCl) is generated due to combustion and thermal decomposition of the chlorine-containing polymer resin, which causes remarkable environmental pollution. In order to prevent the generation of such harmful gases, it is conceivable to separate and remove only the chlorine-containing polymer resin from the synthetic resin in advance, but since the processing cost becomes high, large-scale processing of synthetic resin is not possible. Not suitable.

On the other hand, a method has also been proposed in which waste plastic is oiled to be used as fuel oil. However, in this method, in addition to complicated processing steps, resins having different physical properties and chemical properties (for example, Thermosetting resin and thermoplastic resin must be treated under different operating conditions, and a large amount of hydrogen chloride gas is generated due to the decomposition of chlorine-containing polymer resin, so a large amount of alkaline chemicals is required to neutralize it. However, there are problems in terms of technology and treatment cost such as chlorine being inevitably mixed in the oil component, and it is difficult to say that this is also a method suitable for large-scale treatment of synthetic resins.

Therefore, an object of the present invention is to solve the problems of the prior art and to make synthetic resins such as waste plastics economical without causing problems due to chlorine-containing polymer resins such as vinyl chloride resin. It is an object of the present invention to provide a method which can be treated as a high-calorie fuel, and a method which can economically enable the use of synthetic resins as a high-calorie fuel.

[0006]

In order to solve such problems, the present inventors have developed a hydrochloric acid recovery facility for recovering hydrochloric acid by treating a pickling waste liquid discharged from a pickling facility of an iron mill. Attention was paid to the idea of using a synthetic resin material containing a chlorine-containing polymer resin as a fuel for this type of hydrochloric acid waste liquid treatment facility.

[0007] For example, pickling equipment in a steel mill
This equipment is mainly intended to dissolve and remove the scale (oxide film) generated on the surface of hot-rolled steel in the hot-rolling process of steel with hydrochloric acid solution, and contains iron chloride discharged from this pickling equipment. The pickling waste liquid (hydrochloric acid waste liquid) is sent to a waste liquid treatment facility and is thermally decomposed in a roasting furnace heated to a high temperature by a combustion burner, and hydrochloric acid and a by-product iron oxide are simultaneously recovered. Waste liquid treatment equipment for treating chlorine-containing substances (hydrochloric acid waste liquid) and requiring a fuel for thermally decomposing the waste liquid has a condition that synthetic resins can be used as fuel and chlorine-containing polymer resin It also has the condition that hydrogen chloride generated by combustion can be treated surely. Therefore, by using this kind of equipment, synthetic resins can be produced without any concern about the generation of harmful gas due to the combustion of chlorine-containing polymer resin. Can be used as fuel,
Moreover, the chlorine content of the chlorine-containing polymer resin can be recovered as hydrochloric acid without any special treatment. Based on such an idea, the inventors of the present invention have devised a completely new synthetic resin processing method and equipment using hydrochloric acid recovery equipment such as pickling waste liquid treatment equipment.

That is, the features of the present invention are as follows. (1) A method for treating synthetic resins using a hydrochloric acid recovery facility for thermally decomposing hydrochloric acid waste liquid in a roasting furnace to recover hydrochloric acid, and supplying a synthetic resin material into the roasting furnace. Then, when the chlorine-containing polymer resin is contained in the synthetic resin material, hydrogen chloride generated by the combustion of the chlorine-containing polymer resin is discharged outside the furnace together with hydrochloric acid gas generated by the thermal decomposition of the hydrochloric acid waste liquid. A method for treating synthetic resins, characterized in that it is taken out and recovered as hydrochloric acid.

(2) In the treatment method of (1) above, the hydrochloric acid recovery equipment is attached to the steel material pickling equipment, and the acid pickling waste liquid of the steel material is thermally decomposed in the roasting furnace to recover hydrochloric acid. 5. A method for treating synthetic resins, which is a pickling waste liquid treatment facility. (3) The method for treating synthetic resins according to the method (1) or (2), wherein the synthetic resin material is blown into the roasting furnace through a dedicated supply means. (4) In the treatment method of (1) or (2), synthetic resin is characterized by blowing synthetic resin material into a roasting furnace through a combustion burner for fuel supply or a supply means for oxygen-containing gas supply. Processing method.

(5) In the treatment method of (1) or (2) above, a synthetic resin material is mixed with a hydrochloric acid waste liquid, and the mixture is supplied into a roasting furnace together with the hydrochloric acid waste liquid. Processing method. (6) In the treatment method according to any one of (1) to (5) above, the synthetic resin material is crushed and then supplied into a roasting furnace, and then the synthetic resin is treated. (7) The method for treating synthetic resins according to any one of the above (1) to (6), characterized in that the synthetic resin material is fed into the roasting furnace discontinuously or intermittently.

(8) A facility in which a treatment / supply mechanism for synthetic resins is attached to a hydrochloric acid recovery facility for recovering hydrochloric acid by thermally decomposing a hydrochloric acid waste liquid in a roasting furnace. A hydrochloric acid recovery facility, wherein the mechanism has a crushing device for a synthetic resin material and a supply means for supplying the synthetic resin material crushed by the crushing device directly or indirectly to the roasting furnace. (9) In the treatment equipment of (8) above, a hydrochloric acid recovery equipment is attached to the steel material pickling equipment, and pickling for recovering hydrochloric acid by thermally decomposing the steel material pickling waste liquid in a roasting furnace. A hydrochloric acid recovery facility characterized by being a waste liquid treatment facility. (10) In the facility of (8) or (9) above, the hydrochloric acid recovery facility is characterized in that the means for supplying the synthetic resin material has a dedicated blowing means for blowing the synthetic resin material into the roasting furnace.

(11) In the equipment of (8) or (9) above,
The synthetic resin material supply means is provided to a combustion burner for supplying fuel to the roasting furnace, a supply system for supplying fuel to the combustion burner, or a supply system for supplying oxygen-containing gas to the roasting furnace. Hydrochloric acid recovery equipment, which is a means for supplying synthetic resin material. (12) In the equipment of (8) or (9) above, the means for supplying the synthetic resin material is a means for supplying the synthetic resin material to the supply system for supplying the pickling waste liquid to the roasting furnace. Hydrochloric acid recovery equipment.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention utilizes a hydrochloric acid recovery facility for treating a hydrochloric acid waste liquid such as a pickling waste liquid treatment facility, and supplies a synthetic resin material as a fuel to a roasting furnace constituting this treatment facility. Then, the synthetic resin material is burned in the furnace. This allows
When the synthetic resin material contains a chlorine-containing polymer resin, hydrogen chloride produced by the combustion of this chlorine-containing polymer resin is taken out of the furnace together with hydrochloric acid gas produced by the thermal decomposition of the hydrochloric acid-based waste liquid to produce hydrochloric acid. Be recovered. In the method of the present invention, it does not matter at all whether or not the chlorine-containing polymer resin is contained in the synthetic resin material supplied as a fuel to the roasting furnace. On the other hand, the synthetic resin material supplied as fuel may be substantially composed of chlorine-containing polymer resin. Further, when the synthetic resin material is supplied to the roasting furnace as a part of the fuel, the supply of the synthetic resin material into the furnace during the operation may be discontinuous or intermittent.

FIG. 1 is a conceptual diagram showing an example of the constitution of the method of the present invention using a pickling waste liquid treatment facility in a steel plant as a hydrochloric acid recovery facility. In the figure, 1 is a roasting furnace for separating the pickling waste liquid into hydrochloric acid gas and iron oxide by a thermal decomposition reaction, and 2 is dust removal of hydrochloric acid gas taken out from the furnace top of the roasting furnace (oxidation in hydrochloric acid gas A dust remover such as a cyclone for collecting iron dust 3 is an absorption tower for introducing dust-removed hydrochloric acid gas into a high-concentration hydrochloric acid aqueous solution. Further, 4 is a supply means for supplying the pickling waste liquid to the roasting furnace 1, and 5 is for supplying fuel gas or fuel oil (hereinafter, the case of using the fuel gas will be described as an example) to the roasting furnace 1. Supply means 6 for supplying oxygen-containing gas such as air to the roasting furnace 1,
Reference numeral 7 denotes a returning means for returning the dust collected by the dust remover 2 to the roasting furnace 1, and the supplying means 5 has a combustion burner (not shown) for blowing a fuel gas into the furnace. ing.

In such a pickling waste liquid treatment facility, the pickling waste liquid is treated as follows. That is, the pickling waste liquid (hydrochloric acid waste liquid) is supplied into the roasting furnace 1 through the supply means 4, and the fuel such as B gas (blast furnace gas) or M gas (blast furnace gas + coke oven gas) is supplied through the supply means 5. Gas and oxygen-containing gas (air, oxygen-enriched air, etc.) are supplied through the supply means 6, respectively. The inside of the roasting furnace 1 is heated to a high temperature (for example, about 700 to 800 ° C.) by the combustion of the fuel gas, and the pickling waste liquid is thermally decomposed into hydrochloric acid gas and iron oxide. The iron oxide produced by thermal decomposition is taken out of the furnace from the bottom of the furnace and is recovered as iron oxide suitable as a ferrite raw material. On the other hand, hydrochloric acid gas is taken out of the furnace from the top of the furnace, dust-removed by the dust remover 2, and then sent to the absorption tower 3 to be recovered as a high-concentration hydrochloric acid aqueous solution. The iron oxide dust collected by the dust remover 2 is returned to the roasting furnace 1 through the returning means 7.
Will be returned to

In the method of the present invention, a synthetic resin material is supplied as a fuel to the roasting furnace 1 of such a pickling waste liquid treatment facility. Therefore, in the configuration example of FIG. A kind of processing / supply mechanism A is attached. The processing / supply mechanism A includes a synthetic resin material crushing device 8 and a supply means 9 for transferring the synthetic resin material crushed by the crushing device 8 to the roasting furnace 1 and supplying it into the furnace. Have According to this processing / supply mechanism A, the synthetic resin material is crushed by the crushing device 8
Particle size suitable for blowing into the furnace (for example, particle size 50m
After being crushed into granules or fine particles of about m or less), they are blown into the furnace through the supply means 9 as a part of the fuel. Generally, the supply means 9 is a transfer means (for example, a screw type transfer conveyor or a pneumatic tube) for transferring the synthetic resin material crushed by the crushing device 8 to the roasting furnace 1 and the synthetic resin material transferred. However, the present invention is not limited to this.

When the synthetic resin material supplied to the roasting furnace 1 contains a chlorine-containing polymer resin, hydrogen chloride is generated by the combustion of the synthetic resin material. This hydrogen chloride is the heat of the pickling waste liquid. It is taken out of the furnace together with the hydrochloric acid gas generated by the decomposition, and is recovered as an aqueous hydrochloric acid solution in the absorption tower 3 as described above. Therefore, the synthetic resin material can be used as a fuel without any concern about the problem of generation of hydrogen chloride gas due to the combustion of the chlorine-containing polymer resin, and the synthetic resin material has been conventionally used as a fuel for a roasting furnace. Since the amount of heat is considerably higher than that of the B gas and M gas used, the fuel cost in the roasting furnace can be significantly reduced. In the configuration example of FIG. 1, the synthetic resin material is supplied into the furnace as a part of the fuel, but in some cases, most or all of the fuel may be the synthetic resin material.

Further, in the configuration example of FIG. 1, the synthetic resin material is supplied into the furnace by the dedicated supply means 9, but the method of supplying the synthetic resin material into the roasting furnace 1 is arbitrary. Such a supply method can be adopted. The following (1)
The supply methods (4) to (4) can be similarly applied even when fuel oil is used instead of fuel gas. (1) The synthetic resin material is introduced into the fuel gas supply means 5, and the synthetic resin material is blown into the furnace through the combustion burner while being mixed with the fuel gas. (2) Using a combustion burner that can simultaneously inject fuel gas and synthetic resin material into the furnace, such as a multi-tube combustion burner,
The fuel gas and the synthetic resin material are supplied to the combustion burner by separate supply means, and both are simultaneously blown into the furnace from this combustion burner. (3) introducing a synthetic resin material into the oxygen-containing gas supply means 6,
The synthetic resin material is blown into the furnace while being mixed with the oxygen-containing gas. (4) The synthetic resin material is mixed with the pickling waste liquid and is supplied into the furnace together with the pickling waste liquid through the supply means 4.

FIG. 2 shows a more specific structural example of the method of the present invention using the pickling waste liquid treatment facility in a steel plant as a hydrochloric acid recovery facility. The same equipment as in FIG. There is. In the figure, 10 is a concentrating tower for introducing the hydrochloric acid gas dedusted by the dust collector 2 and cooling it to condense the water into a high-concentration hydrochloric acid gas, and 11 is just before being introduced into the concentrating tower 10. Supplying means for adding water to the hydrochloric acid gas of 12; 12 supplying means for supplying water to the absorption tower 3;
3 is a hydrochloric acid recovery tank for recovering the hydrochloric acid aqueous solution taken out from the absorption tower 3, and 14 is an iron oxide recovery hopper for recovering the iron oxide taken out from the roasting furnace 1.

The pickling waste liquid before being supplied to the roasting furnace 1 is temporarily stored in the concentration tower 10.
The hydrochloric acid gas to which water was added by the supply means 11 immediately before was cooled by contact with the added water and the pickling waste liquid in the tower, and the water content in the gas was condensed to increase the concentration. , Is guided outside the tower. Further, the added water and the water content in the condensed gas become a part of the pickling waste liquid in the concentration tower 10, and the pickling waste liquid is supplied to the roasting furnace 1.

The iron oxide produced in the roasting furnace 1 is taken out of the furnace from the bottom of the furnace and is recovered in the iron oxide recovery hopper 14, and the hydrochloric acid aqueous solution taken out from the absorption tower 3 is recovered in the hydrochloric acid recovery tank 13. It 1 and 2, the processing / supply mechanism A for the synthetic resin material having the crushing device 8 is provided. However, for example, without crushing device, processing processing such as crushing is performed offline. The synthetic resin material may be transported to the pickling waste liquid treatment facility and supplied to the roasting furnace 1 by any of the above-described supply methods.

There is no particular restriction on the type of the roasting furnace 1 of the hydrochloric acid recovery equipment used in the method of the present invention. 3 and 4 show typical types of roasting furnaces in hydrochloric acid recovery equipment (particularly, pickling waste liquid treatment equipment). Fig. 3
Is a fluidized bed type roasting furnace, a dispersion plate 15 for forming a fluidized bed is provided inside the roasting furnace 1, and a gas blowing chamber 16 below the dispersion plate 15 is supplied to the gas blowing chamber 16 through a supply means 6. An oxygen-containing gas such as air is supplied, and the oxygen-containing gas flows into the reaction chamber 17 through a through hole (not shown) formed in the dispersion plate 15 to form a fluidized bed. Also,
The distribution plate 15 is provided with a combustion burner 18, and the supply means 5
Through which combustion gas is supplied. On the other hand, the pickling waste liquid and the synthetic resin material are directly supplied into the reaction chamber 17 through the supplying means 4 and the supplying means 9, respectively. The synthetic resin material may be supplied into the furnace through the supply means 4 or the supply means 5 and the combustion burner 18 as described above.

FIG. 4 shows a spray-type roasting furnace. A spray nozzle 19 for spraying the pickling waste liquid toward the lower part of the furnace is provided in the upper part of the roasting furnace 1. 19, the pickling waste liquid is supplied through the supply means 4, and the supply means 5 (combustion burner 20) is provided on the lower side of the furnace
The fuel gas, the oxygen-containing gas and the synthetic resin material are respectively supplied through the supply means 6 and the supply means 9. Further, the type of the roasting furnace is not limited to the above, and any type such as a rotary kiln type roasting furnace can be adopted.

In the method of the present invention, it is conceivable that a part of the synthetic resin material supplied to the furnace will be gasified by thermal decomposition without being burned, but in this way, a part of the synthetic resin material is burned. The effect of the present invention will not be impaired even if gasification is carried out by thermal decomposition without using it. Further, the method of the present invention can be used regardless of the type as long as it is a hydrochloric acid recovery facility for thermally decomposing a hydrochloric acid waste liquid in a roasting furnace to recover hydrochloric acid. However, it is most preferable to use the above-mentioned pickling waste liquid treatment facility from the viewpoint of utilizing existing facilities in a steel mill and consuming a large amount of synthetic resins as fuel efficiently.

[0025]

[Examples] In a pickling waste liquid treatment facility (a roasting furnace is a fluidized bed type shown in FIG. 3) in a steel plant having the configuration of FIG. The method (comparative example) was carried out. The standard operating conditions (operating conditions corresponding to the following comparative example) in the pickling waste liquid treatment facility are: pickling waste liquid treatment amount: 3290 m ³ / month (H in waste liquid)
Cl concentration: 3.8%, Fe concentration: 8.5%), fuel gas supply amount: 1.4 million Nm ³ / month, air supply amount: 4.44 million N
m ³ / month, hydrochloric recovered amount: 3164m ³ / month (HCl concentration:
17.85%), and iron oxide recovery: 480 t / month.

Example 1: Waste synthetic resin material containing no chlorine-containing polymer resin (heating value: 9500 kcal / kg)
200k of crushed material is supplied to the roasting furnace as a part of fuel
It was supplied at g / h. Example 2: A crushed material of a waste synthetic resin material (heating value: 8295 kcal / kg) containing about 15 wt% of a chlorine-containing polymer resin is supplied to a roasting furnace as a part of fuel at an amount of 200 kg /
h. Example 3: A crushed material of a synthetic resin material (heat generation amount: 4300 kcal / kg) consisting essentially of a chlorine-containing polymer resin is supplied to a roasting furnace as a part of fuel at an amount of 200 kg / h.
Supplied with Comparative Example: The roasting furnace was operated under the conventional conditions in which the synthetic resin material was not supplied.

Table 1 shows the supply amount of the fuel gas (M gas) in Examples 1 to 3 and the comparative example, the increased amount of the recovered hydrochloric acid (the increased amount in the case of using the comparative example as a reference), and the recovered amount. It also shows the chlorine content in iron oxide. From the results in the table, it is possible to reduce the fuel gas by supplying the synthetic resin material, which is a waste, to the roasting furnace as a part of the fuel, and the chlorine content in the synthetic resin material supplied as fuel is high. Even if the molecular resin is included or the synthetic resin material is a chlorine-containing polymer resin, the hydrogen chloride gas generated by the combustion is surely recovered as hydrochloric acid together with the hydrochloric acid generated by the thermal decomposition treatment of the pickling waste liquid. Therefore, it is clear that the amount of recovered hydrochloric acid also increases, and that the quality (chlorine content) of iron oxide recovered as a by-product is not much different from the quality of iron oxide obtained in normal operation. .

[0028]

[Table 1]

[0029]

As described above, according to the present invention, a synthetic resin such as a plastic, which is a waste, is used as a fuel without any fear of the generation of harmful gas due to the combustion of the chlorine-containing polymer resin. This enables large-scale processing and effective utilization of waste of synthetic resins. Moreover, according to the present invention, chlorine contained in the chlorine-containing polymer resin can be effectively recovered as hydrochloric acid, and the fuel cost of the hydrochloric acid recovery facility can be significantly reduced. As described above, according to the present invention, it is possible to obtain an excellent effect that the operating cost of the hydrochloric acid recovery equipment such as the pickling waste liquid treatment equipment can be reduced and the economical large-scale treatment of the synthetic resin as the waste can be simultaneously achieved. Therefore, it can be said that the present invention is a very useful invention in the present situation in which the establishment of a technology for treating wastes of synthetic resins is earnestly desired.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a configuration example of the method of the present invention using a pickling waste liquid treatment facility as a hydrochloric acid recovery facility.

FIG. 2 is a conceptual diagram more specifically showing one structural example of the method of the present invention using a pickling waste liquid treatment facility as a hydrochloric acid recovery facility.

FIG. 3 is an explanatory diagram showing a configuration example of a roasting furnace of the hydrochloric acid recovery facility shown in FIG. 1 or 2.

FIG. 4 is an explanatory diagram showing another configuration example of the roasting furnace of the hydrochloric acid recovery facility shown in FIG. 1 or FIG.

[Explanation of symbols]

1 ... Roasting furnace, 2 ... Dust remover, 3 ... Absorption tower, 4, 5, 6 ... Supplying means, 7 ... Returning means, 8 ... Crushing device, 9 ... Supplying means,
10 ... Concentration tower, 11, 12 ... Supply means, 13 ... Hydrochloric acid recovery tank, 14 ... Iron oxide recovery hopper, 15 ... Dispersion plate, 16
… Gas injection chamber, 17… Reaction chamber, 18… Combustion burner, 19
... Spray nozzle, 20 ... Combustion burner, A ... Treatment / supply mechanism

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsutomu Shibata 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Japan Steel Tube Co., Ltd. (72) Tsuneo Nagaoka 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Date Main Steel Pipe Co., Ltd.

Claims (12)

[Claims] 1. A method for treating synthetic resins using a hydrochloric acid recovery facility for thermally decomposing hydrochloric acid waste liquid in a roasting furnace to recover hydrochloric acid, wherein the synthetic resin material is used in the roasting furnace. When the synthetic resin material contains a chlorine-containing polymer resin, the hydrogen chloride produced by the combustion of the chlorine-containing polymer resin is mixed with the hydrochloric acid gas produced by the thermal decomposition of the hydrochloric acid-based waste liquid in the furnace. A method for treating synthetic resins, characterized in that it is taken out to the outside and recovered as hydrochloric acid. 2. A hydrochloric acid recovery equipment is attached to a steel material pickling equipment, and is a pickling waste liquid treatment equipment for thermally decomposing a steel material pickling waste solution in a roasting furnace to recover hydrochloric acid. The method for treating synthetic resins according to claim 1, which is characterized in that. 3. The method for treating synthetic resins according to claim 1, wherein the synthetic resin material is blown into the roasting furnace through a dedicated supply means. 4. The method for treating synthetic resins according to claim 1, wherein the synthetic resin material is blown into the roasting furnace through a combustion burner for supplying fuel or a supply means for supplying oxygen-containing gas. . 5. The method for treating synthetic resins according to claim 1, wherein the synthetic resin material is mixed with a hydrochloric acid-based waste liquid and is supplied into the roasting furnace together with the hydrochloric acid-based waste liquid. 6. The method for treating synthetic resins according to claim 1, wherein the synthetic resin material is crushed and then fed into a roasting furnace. 7. The synthetic resin material is discontinuously or intermittently supplied into the roasting furnace.
4. The method for treating synthetic resins according to 4, 5 or 6. 8. A facility in which a treatment / supply mechanism for synthetic resins is attached to a hydrochloric acid recovery facility for recovering hydrochloric acid by thermally decomposing a hydrochloric acid waste liquid in a roasting furnace, the treatment / supply mechanism. Is equipped with a synthetic resin material crushing device and a supply means for supplying the synthetic resin material crushed by the crushing device directly or indirectly to the roasting furnace. 9. A hydrochloric acid recovery equipment is attached to a steel material pickling equipment, and is a pickling waste liquid treatment equipment for thermally decomposing a steel material pickling waste solution in a roasting furnace to recover hydrochloric acid. The hydrochloric acid recovery equipment according to claim 8, which is characterized in that. 10. The hydrochloric acid recovery facility according to claim 8 or 9, wherein the synthetic resin material supply means has a dedicated blowing means for blowing the synthetic resin material into the roasting furnace. 11. The synthetic resin material supply means supplies an oxygen-containing gas to a combustion burner for supplying fuel to the roasting furnace, a supply system for supplying fuel to the combustion burner, or the roasting furnace. 10. The hydrochloric acid recovery equipment according to claim 8 or 9, which is a means for supplying a synthetic resin material to the supply system. 12. The synthetic resin material supply means is a means for supplying the synthetic resin material to a supply system for supplying a hydrochloric acid waste liquid to a roasting furnace.
Hydrochloric acid recovery equipment described in.