JPH11198142A - Method for regenerating treatment of waste plastic and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To significantly inhibit the corrosion of an installation by a harmful substance by adding lime water as a neutralizer and a precipitating agent in the early stage of treatment and supply a neutralization cleaning water used for cleaning in the early stage into a breaking machine for circulatory use. SOLUTION: In the method and the device for the regenerating treatment of waste plastic, the waste plastic contaminated by acid, alkali, heavy metals, oils or the like is coarsely broken while adding a neutralization cleaning water and a lime water. Further, the broken and neutralized waste plastic mass is cleaned in an early-stage cleaning tank 4 using the neutralization cleaning water containing the lime water. After that, the plastic mass cleaned in the early-stage cleaning tank 4 is finely ground and the finely ground plastic is cleaned, dehydrated and dried in a final-stage cleaning tank 12 with the neutralization cleaning water.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for reprocessing waste plastic, and more particularly, to regenerating plastic waste to which acid, alkali, heavy metal, oil and the like are adhered, for example, a waste storage battery case. The present invention relates to a method and an apparatus.

[0002]

2. Description of the Related Art Conventionally, as a method for regenerating a battery case, there are methods disclosed in, for example, JP-A-52-152976 and JP-A-57-15371.

[0003]

However, in the above-mentioned conventional method, a large amount of wastewater which may pollute the environment, such as acid, fine powder of lead, lead ions, etc., is generated from the water washing step. Large scale equipment and cost were required.

Further, in order to prevent corrosion due to dilute sulfuric acid in the battery, all equipment up to the water washing step had to be expensive corrosion-resistant equipment.

The present invention has been made to eliminate the above disadvantages.

[0006]

SUMMARY OF THE INVENTION An apparatus for reclaiming waste plastic according to the present invention comprises a coarse crusher for coarsely crushing waste plastic, a first-stage cleaning tank for cleaning waste plastic lumps obtained by coarsely crushing, and a first-stage cleaning tank. A means for supplying lime water into the washing tank and the coarse crusher, a fine crusher for finely pulverizing the waste plastic lump washed in the first-stage cleaning tank, and a final-stage cleaning tank for washing the finely pulverized plastic. Drying means for drying the finely pulverized plastic washed by the final washing tank, and means for supplying neutralizing washing water into the first-stage washing tank, the last-stage washing tank and the coarse crusher. I do.

[0007] It is characterized in that there is further provided a means for circulating the neutralized washing water containing lime water in the first-stage dewatering tank to form a water flow in the first-stage washing tank.

The waste plastic recycling method according to the present invention comprises a step of roughly crushing waste plastic while adding neutralizing washing water and lime water, and a step of removing crushed and neutralized waste plastic lumps in a first stage cleaning tank. A step of washing with a neutralized washing water containing, a step of pulverizing the plastic lump washed in the first-stage washing tank, and a step of washing the finely pulverized plastic with the neutralized washing water in the final-stage washing tank. Dewatering and drying the finely pulverized and washed plastic.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

In the method for reclaiming waste plastic according to the present invention, as shown in FIG. 1, a waste storage battery case to be treated is put into a crusher 2 via a conveyor 1 and roughly crushed into a lump of 15 mm or less, for example. Then, neutralizing washing water is injected into the crusher 2 via a line 3 and lime water is injected as described later to neutralize dilute sulfuric acid and the like adhering to the waste storage battery case. .

The crushed and neutralized waste plastic lumps fall into the first-stage washing tank 4, and a PH of 7 is supplied from an emulsifying tank 5 for stirring and mixing slaked lime and water at one upper end of the first-stage washing tank 4.
The lime water, which has been set to ９9, is added via a line 6, and the neutralized washing water is added via a line 7, and the water in the first washing tank 4 is pumped from the lower end of the other end via a pump 8 to one end of the first washing tank 4. To form a water flow from one end to the other in the first-stage cleaning tank 4.

A perforated air pipe 9 for aeration is arranged on the inner lower surface of the first-stage cleaning tank 4 to aerate the paste, waste plastic lump, neutralized sediment, lead powder, gypsum, sand, etc. deposited on the lower surface. Then, the waste plastic lump is separated and sent out from the other end opening into the cutter pump 10 with the help of the water flow in the first-stage washing tank 4, for example, 5 mm
Finely crush to size.

The plastic finely pulverized by the cutter pump 10 is sent onto a net of a dewatering tank 11, where the plastic and the neutralized washing water are separated, the plastic is dropped into a final washing tank 12, and a line 13 is formed. It is washed with neutralized washing water added thereto, and then dehydrated and dried by a dehydration dryer 14, and is taken out as clean and finely pulverized plastic having a uniform particle size.

The neutralized washing water in the dewatering tank 11 and the final washing tank 12 is returned to the first washing tank 4 via lines 15 and 16 using a pump or the like. The neutralized washing water containing lime water in the first washing tank 4 is supplied by a pump 8 into the crusher 2 via a line 17 so as to prevent the crusher 2 from being corroded by acid. It is circulated through the line 18 into the first-stage cleaning tank 4.

When the amount of neutralized sediment deposited in the first-stage cleaning tank 4 reaches a certain amount, the circulating neutralized washing water is removed, and the neutralized sediment is extracted using a submersible pump or the like and recycled as lead resources. .

The waste plastic recycling apparatus according to the present invention comprises a coarse crusher 2 for coarsely crushing waste plastic contaminated by acids, alkalis, heavy metals, oils and the like, and a waste plastic lump obtained by coarsely crushing. A first-stage cleaning tank 4; a pump 8 for supplying lime water into the first-stage cleaning tank 4 and the coarse crusher 2; a cutter pump 10 for finely pulverizing waste plastic lump washed in the first-stage cleaning tank 4; A final washing tank 12 for washing the finely pulverized plastic, a dehydration dryer 14 for drying the finely pulverized plastic washed by the final washing tank 12, the first washing tank 4, the last washing tank 12, Lines 7, 13, and 3 for supplying neutralizing washing water into the coarse crusher 2.

In the waste plastic recycling apparatus of the present invention, neutralizing washing water containing lime water in the first-stage dewatering tank 4 is circulated by a circulation pump 8 in order to form a water flow in the first-stage washing tank.

[0018]

As described above, in the present invention, the washing of waste plastic is divided into two stages, a first stage and a last stage. In the first stage, lime water is added as a neutralizing agent and a sedimentation agent. Since the used neutralizing washing water is supplied into the crusher and is used in a circulating manner, corrosion of the equipment due to harmful substances can be significantly suppressed.

Further, since the washing water used for washing in the first stage and the last stage is circulated and used, there is a great advantage that the amount of wastewater which may pollute the environment can be suppressed.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a method and an apparatus for reclaiming waste plastic according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Conveyor 2 Rough crusher 3 line 4 First stage washing tank 5 Emulsification tank 6 line 7 line 8 Circulation pump 9 Air pipe 10 Cutter pump 11 Dehydration tank 12 Final washing tank 13 line 14 Dehydration dryer 15 line 16 line 18 line 18 line

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI B29K 105: 26

Claims (3)

[Claims] 1. A coarse crusher for coarsely crushing waste plastics, a first-stage cleaning tank for cleaning waste plastic lumps obtained by coarsely crushing, and means for supplying lime water into the first-stage cleaning tank and the coarse crusher. A fine crusher for finely pulverizing the waste plastic lump washed in the first-stage cleaning tank, a final-stage cleaning tank for cleaning the finely-ground plastic, and a finely-crushed plastic washed by the final-stage cleaning tank. An apparatus for reclaiming waste plastics, comprising: drying means for drying; and means for supplying neutralizing washing water into the first-stage washing tank, the last-stage washing tank, and the coarse crusher. 2. The recycling of waste plastic according to claim 1, further comprising means for circulating neutralized washing water containing lime water in the first-stage dewatering tank to form a water flow in the first-stage washing tank. Processing equipment. 3. A step of coarsely crushing waste plastic while adding neutralizing washing water and lime water, and washing the crushed and neutralized waste plastic lump with neutralizing washing water containing lime water in a first-stage washing tank. A step of finely pulverizing the plastic lump washed in the first-stage cleaning tank; a step of cleaning the finely pulverized plastic with neutralizing cleaning water in the final-stage cleaning tank; A method for recycling waste plastics, comprising: dehydrating and drying.