JP2006326448A - Separation recovery apparatus for mixture, production method for plastic material or plastic molding body using it and plastic material or plastic moulding body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a simple and efficient separation recovery device capable of separating a mixed plastic member in every system of a plastic composition, producing the plastic material or the plastic molding body from the plastic composition by material recycle and reducing the thermally recycled plastic waste material; more efficient plastic material or plastic molding body than the conventional one; and a production method for the plastic material or the plastic molding body. <P>SOLUTION: The separation recovery apparatus is provided with a wetting means for exposing a mixture constituted by a plurality of kinds of materials having different specific gravities to a wetting liquid and thereafter exposing it to an atmosphere of gas; and a specific gravity separation means for separating the mixture after it is exposed to the atmosphere of gas by the wetting means to a high specific gravity substance and a low specific gravity substance by a liquid. The separation recovery apparatus in which a pump is arranged on the wetting means; the production method for the plastic material or the plastic molding body using it; and the plastic material or the plastic molding body are provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a separation and recovery apparatus for a mixture. The present invention also relates to a method for producing a plastic raw material or a plastic molded body using the above-described mixture separation and recovery apparatus, and the obtained plastic raw material or plastic molded body.

  In recent years, with the improvement of income levels in Japan, an air conditioner (referred to as “air conditioner” in this specification), a television receiver (referred to as “TV” in this specification), Home appliances such as refrigerators and washing machines, personal computers, information devices such as word processors, office equipment such as printers and fax machines, and various other furniture, stationery, and toys are provided at a high penetration rate in general households. Convenience in home life has been dramatically improved.

  On the other hand, as a result, the amount of disposal of various products including these home appliances also tends to increase year by year. Here, conventionally, the recycling of waste products such as home appliances has often been performed through a scrap recovery route.

  However, in recent years, the constituent materials of members of various products such as home appliances have changed, and the number of members made of metals such as iron has decreased and the proportion of members made of plastic compositions has increased. Plastic compositions have a greater degree of design freedom than metals such as iron, and can be imparted with various properties that are difficult to achieve with metals by preparing components and using additives, and are lightweight and durable. This is because it has many advantages such as high performance.

  In the present specification, a member made of a plastic composition is referred to as a “plastic member”. In the present specification, a product provided with a plastic member is referred to as a “plastic product”. Further, in the present specification, plastic product waste is also referred to as “plastic waste”.

  The waste of various products including household appliances in recent years has a complicated material composition of various components, and the proportion of components made of valuable metals such as iron and copper is small, and the value is low. The proportion of plastic members that require a lot of labor and cost is high in the conventional processing method, and it is difficult to deal with the conventional iron scrap collection route because it is not profitable even if such waste is recycled. It is becoming a situation.

  Many of these plastic members are synthesized using embedded fossil fuels such as crude oil as a basic raw material, and in recent years, there has been a strong demand for recycling these plastic products from the viewpoint of effective use of resources. Yes.

  In addition, environmental pollution such as global warming and acid rain due to the release of carbon dioxide and sulfur oxides from combustion of buried fossil fuels such as crude oil, and environmental pollution such as dioxin generation and scattering due to incineration of plastic compositions containing chlorine compounds. In addition, from the viewpoint of suppressing the problem of a shortage of landfill disposal sites due to an increase in bulky plastic waste, the recycling of plastic waste is becoming an important and urgent issue.

  In response to the above situation, the Home Appliance Recycling Law was enforced in April 2001. Here, according to the Home Appliance Recycling Law, as of January 2002, it is obliged to recycle four items of home appliances such as air conditioners, televisions, refrigerators, and washing machines. Legal reference values are set for% or more, television 55% or more, refrigerator 50% or more, and washing machine 50% or more.

  However, plastic products such as these home appliances generally include a plurality of plastic members, and these plastic members are often made of different plastic compositions, and are composite members made of different plastic compositions. Often it is.

  In the present specification, a member made of a plurality of plastic compositions of different materials or a composite member made of plastic compositions of different materials is referred to as a “mixed plastic member”. In the present specification, a product including a mixed plastic member is also referred to as a “mixed plastic product”. Further, in this specification, the waste of the mixed plastic product is also referred to as “mixed plastic waste”.

  Here, in order to process the mixed plastic member contained in these mixed plastic wastes again and use it as a member of various mixed plastic products such as home appliances or as a raw material thereof, these mixed plastic members are made of plastic. It is necessary to process again after separating for each system of the composition. In this specification, after processing the waste in this way, processing and using the product member or its raw material again is referred to as “material recycling” in contrast to thermal recycling.

  On the other hand, there are many methods for recycling plastic waste that have been proposed so far by separating plastic waste containing only a single plastic composition by manual disassembly. However, such a method of separating and recycling by manual disassembly has a problem that it takes a lot of labor and cost. Furthermore, there is a problem that such a method cannot cope with mixed plastic waste.

  Further, as a method for avoiding such a problem, a method related to so-called thermal recycling in which a mixed plastic member is separated from a mixed plastic waste and used as a fuel without being classified according to the system of the plastic composition. Many proposals have been made.

  In this way, as a method of recycling mixed plastic waste by thermal recycling, for example, in Patent Document 1, a mixed plastic member separated from mixed plastic waste is subjected to pyrolysis decomposition in a pyrolysis furnace, cracked gas and A method of using oil as fuel is disclosed. However, according to this method, it is possible to recycle mixed plastic waste by thermal recycling, but there are problems such as the generation of carbon dioxide by fuel, so it is a method that fully meets social demands. I can't say that.

  Therefore, many development efforts have been made in various fields regarding a method of separating a mixed plastic member from a mixed plastic waste and further separating the mixed plastic member for each system of plastic composition.

For example, a method of separating a plastic composition for each system in a liquid using a specific gravity difference of a mixed plastic member has been widely used. That is, when the mixed plastic member or the crushed material of the mixed plastic member is put into the liquid, a material smaller than the liquid specific gravity floats, and a material larger than the liquid specific gravity separates by using sedimentation. However, according to this method, the influence of bubbles adhering to the plastic is large, and it cannot be said that the method has a sufficient sorting ability particularly for separating the crushed material of the mixed plastic member.
JP-A-6-226242

  In view of the above-described conventional problems, the applicant of the present invention exposes a plastic waste composed of a plurality of types of plastics to a liquid atmosphere and then exposes the plastic waste to a gas atmosphere in order to reduce the effect of bubbles attached to the plastic. After the surface is sufficiently wetted, a method of separating and recovering plastic waste material in liquid again is proposed. According to this method, it is possible to obtain a high-quality plastic molded body that can be applied to various applications by material recycling using plastic waste as the main raw material, and reduce plastic waste that is thermally recycled. Therefore, it is possible to provide an efficient method for recycling plastic waste.

  The present applicant has proposed a method in which the plastic waste material is settled in the wetting liquid and vibrated in the wetting liquid as a method for exposing the plastic waste material to the liquid atmosphere. In addition, as a method of exposing plastic waste to a gas atmosphere, a method of taking out from a wetting liquid with a colander, mesh, fabric, paper or the like was proposed. However, in order to carry out the above method easily and automatically, at least a device for precipitating the plastic waste material in the wetting liquid, a device for vibrating in the wetting liquid, and a device for removing it from the wetting liquid are required. It tends to end up. In addition, it is highly desirable to develop an apparatus that automatically performs the above method.

  In this way, after the mixture composed of a plurality of kinds of materials with different specific gravity recovered from the market, in particular, the mixed plastic waste material is exposed to the gas atmosphere after being exposed to the liquid atmosphere, and the plastic waste material surface is sufficiently wetted, In spite of the demand for the development of a simple and efficient separation and recovery device that can separate and recover plastic waste materials in liquid again, such a device has not yet been proposed.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide a mixture of a plurality of types of materials having different specific gravities collected from the market, in particular, a mixed plastic member from plastic waste. In addition, the mixed plastic member can be separated for each system of the plastic composition, and a plastic raw material or a plastic molded body can be produced from the plastic composition by material recycling. It is to provide a simple and efficient separation and recovery device that can reduce waste materials.

  More specifically, the object of the present invention is preferably used in a method of separating a plastic composition for each system in a liquid using a specific gravity difference of a mixture composed of a plurality of materials, particularly a mixed plastic member. Separating and collecting apparatus to obtain a mixed plastic member from a mixture recovered from the market, in particular mixed plastic waste, by simply and efficiently removing air bubbles adhering to the surface of the mixture to be processed, particularly plastic waste. Separately, the mixed plastic member can be further separated for each system of the plastic composition, and a plastic raw material or a plastic molded body can be produced from the plastic composition by material recycling. Can be reduced, simple and efficient To provide a separation and recovery device.

  Another object of the present invention is to separate the mixed plastic member from the mixed plastic waste collected from the market, and further to separate the mixed plastic member for each system of the plastic composition. An object of the present invention is to provide a method for producing a plastic raw material or a plastic molded body from material by material recycling.

  Still another object of the present invention is to provide a plastic raw material or a plastic molded body obtained by material recycling from mixed plastic waste recovered from the market.

  In order to solve the above-mentioned problems, the present invention exposes a mixture composed of a plurality of kinds of materials having different specific gravities to a wetting liquid, and then exposes the mixture to a gas atmosphere. A separation and recovery device for a mixture composed of a plurality of kinds of materials having different specific gravities, comprising a specific gravity separation means for separating a later mixture into a high specific gravity material and a low specific gravity material in a liquid, and is simple and efficient. In order to develop an apparatus for separating and recovering such a mixture, the mixture and the wetting liquid are agitated with the wetting liquid used in the wetting means. Experiments were conducted on many types of methods such as a method, a transport method, and a method of taking out the mixture from the wetting means, and extensive studies were made. That is, the present invention is as follows.

  The separation and recovery device of the present invention comprises a wet means for exposing a mixture composed of a plurality of types of materials having different specific gravities to a wetting liquid, and then exposing the mixture to a gas atmosphere, and a mixture after being exposed to the gas atmosphere by the wet means. A separation / collection device for a mixture composed of a plurality of kinds of materials having different specific gravity, comprising a specific gravity separation means for separating a liquid into a high specific gravity material and a low specific gravity material, wherein a pump is disposed in the wetting means It is characterized by being formed.

  Here, it is preferable that the pump is capable of stirring the mixture and the wetting liquid and transporting the mixture together with the wetting liquid.

The pump in the separation and recovery apparatus of the present invention is preferably a submersible pump.
It is preferable that the wetting means in the separation and recovery apparatus of the present invention has a transporting means capable of separating the mixture and the wetting liquid transported using the pump.

  It is preferable that the conveying means is configured to separate the mixture and the wetting liquid and simultaneously expose the separated mixture to a gas atmosphere.

  Moreover, it is preferable that the said conveyance means inclines at an angle of 5 degrees-45 degrees so that it may go upwards as it goes to a conveyance direction.

  The separation / recovery device of the present invention has a wetting liquid storage tank for storing the mixture and the wetting liquid conveyed using the pump, and the mixture and the mixture are transferred to the conveying means from the wetting liquid storage tank. It is preferable that it is comprised so that a wetting liquid may be supplied.

  In the separation and recovery device of the present invention, it is preferable that the mixture and the wetting liquid transported using the pump are configured to be directly transported to the transporting means.

  Moreover, it is preferable that the said wetting means further has a collection | recovery means for collect | recovering the wetting liquid isolate | separated by the said conveyance means.

Moreover, it is preferable that the said conveyance means is installed above the pump.
In the separation and recovery device of the present invention, the pump is disposed in a wetting liquid storage tank that contains a wetting liquid therein, and a mixture for introducing the mixture into the pump in the wetting liquid storage tank. It is preferable that a charging portion is provided, and that the inside of the mixture charging portion and the inside of the wetting liquid storage tank communicate with each other so that the wetting liquid can pass therethrough.

  Moreover, it is preferable that the separation and recovery apparatus of the present invention further includes a liquid level adjusting means for adjusting the liquid level of the wetting liquid in the mixture charging unit.

  The liquid level adjusting means is at least one near the liquid level of the wetting liquid in the wetting liquid storage tank and at a height at which the wetting liquid continuously flows from the wetting liquid storage tank to the mixture charging unit. It is preferable that it is installed.

  In the separation and recovery apparatus of the present invention, it is preferable that the charged mixture and the wetting liquid form a cyclone flow in the mixture charging portion.

  Moreover, it is preferable that a part of the mixture charging portion is formed in a substantially conical shape.

  Moreover, it is preferable that the liquid level height of the wetting liquid in the mixture charging part is adjusted to be lower than the liquid level height of the wetting liquid in the wetting liquid storage tank.

  In the separation and recovery device of the present invention, it is preferable that the wetting liquid recovered by the recovery means is input into the mixture input unit.

In the separation and recovery apparatus of the present invention, the wetting liquid is preferably water.
Moreover, it is preferable that the said mixture contains the plastic waste material comprised by multiple types of plastics, and it is preferable that the said plastic waste material is a crushed material of the product provided with the plastic molding or the plastic molding. Here, the particle size of the crushed material is preferably 5 to 30 mm. Moreover, it is preferable that the product provided with the said plastic molding is a product chosen from the group which consists of an air conditioner, a television, a refrigerator, and a washing machine.

  In the present invention, the plastic waste material is preferably at least one selected from the group consisting of polyolefin plastic compositions, polystyrene plastic compositions, and other series of plastic compositions.

  In the separation and recovery apparatus of the present invention, it is preferable that the polyolefin plastic composition and / or the polystyrene plastic composition and / or other series of plastic compositions are separated and recovered.

  Moreover, this invention provides the manufacturing method of the plastic raw material using the separation-and-recovery apparatus of this invention mentioned above, and the plastic raw material obtained by it. The plastic raw material of the present invention is preferably in the form of pellets.

  The present invention also provides a method for producing a plastic molded article using the above-described separation and recovery apparatus of the present invention, and a plastic molded article obtained thereby. The plastic molded article of the present invention is preferably used for a product selected from the group consisting of an air conditioner, a television, a refrigerator, and a washing machine.

  INDUSTRIAL APPLICABILITY According to the present invention, a mixture composed of a plurality of types of materials having different specific gravities collected from the market, particularly plastic waste, can be applied to various applications by material recycling using the mixture, particularly plastic waste as a main raw material. It is possible to provide a simple and efficient apparatus for separating and recovering a mixture, which can obtain a high-quality plastic molded body and can reduce plastic waste that is thermally recycled.

  In addition, according to the present invention, there is provided a method for producing a high-quality plastic raw material applicable to various uses and a method for producing a plastic molded body by material recycling using plastic waste as a main raw material from plastic waste. Can do.

  Furthermore, according to the present invention, it is possible to provide a high-quality plastic raw material and a plastic molded body that can be applied to various uses, obtained by material recycling using plastic waste as a main raw material.

  FIG. 1 is a diagram schematically showing a mixture separation and recovery apparatus according to a preferred example of the present invention. The separation / recovery device of the present invention comprises a wetting means 1 for exposing a mixture composed of a plurality of materials having different specific gravities to a wetting liquid and then exposing to a gas atmosphere, and a mixture after being exposed to a gas atmosphere by the wetting means. Is basically provided with specific gravity separation means 2 for separating the liquid into a high specific gravity material and a low specific gravity material.

  The separation / recovery device of the present invention is characterized in that the pump 7 is disposed in the wet means 1. As the pump 7, a conventionally known appropriate one can be used, and is not particularly limited, but the mixture and the wetting liquid can be stirred, and the mixture can be conveyed together with the wetting liquid. It is preferable. Moreover, it is preferable to use a submersible pump as the pump 7. This is because the wet liquid 4 and the mixture are better agitated when passing through the impeller of the submersible pump by powerful suction with the submersible pump.

  The wetting means 1 in the separation and recovery apparatus shown in FIG. 1 has a wetting liquid storage tank 13 in which a wetting liquid 4 is accommodated. In this wetting liquid storage tank 13, a pump 7 is disposed, and a mixture charging unit 12 opened on one side (the liquid surface side of the wetting liquid 4) is installed in order to charge the pump 7 with the mixture. Being done. The mixture charging unit 12 and the wetting liquid storage tank 13 communicate with each other so that the wetting liquid can pass therethrough. The pump 7 is connected via a pipe 5 to a wetting liquid storage tank 8 installed separately from the wetting liquid storage tank 13. In this way, the contents (mixed mixture) of the mixture charging unit 12 are configured to be transferred to the wetting liquid storage tank 8 through the pump 7 and the pipe 5 together with the wetting liquid 4. Further, the mixture charging unit 12 has a liquid level adjusting means 6 for adjusting the liquid level height of the wetting liquid 4 therein.

  In the separation / recovery device of the present invention, it is preferable that the mixture charging unit 12 is such that the wetting liquid 4 and the mixture can form a cyclone flow therein. When the wetting liquid 4 and the mixture form a cyclone flow, the mixture and the wetting liquid 4 are easily stirred, and the liquid level of the wetting liquid in contact with the inner wall of the mixture charging section 12 is near the center of the mixture charging section 12. Since it can be made higher than the liquid level of the wetting liquid, there is an effect of reducing the amount of bubbles entrained by the wetting liquid 4 flowing from the liquid level adjusting means 6. The means for forming the cyclone flow is not particularly limited. However, as shown in FIG. 1, a portion of the mixture charging portion 12 is gradually increased in diameter toward the upper side (input port side). An example of forming a cone is given. Further, as shown in FIG. 1, the liquid level adjusting means 6 is installed in the vicinity of the liquid level 3 of the wetting liquid 4 in the wetting liquid storage tank 13, and along the wall surface formed in the substantially conical body of the mixture charging unit 12. It is conceivable that the wetting liquid 4 is allowed to flow.

  The liquid level adjusting means 6 provided in the mixture charging unit 12 is not particularly limited as long as the liquid level of the wetting liquid in the mixture charging unit 12 can be adjusted. It is preferable that at least one of the wetting liquids 4 in the vicinity of the liquid level of the wetting liquid 13 is installed at a height at which the wetting liquid 4 flows continuously from the wetting liquid storage tank to the mixture charging unit. Such a liquid level adjusting means 6 is, for example, a hole provided in the wall surface of the mixture charging unit 12 so that the wetting liquid 4 can communicate with each other through the wetting liquid storage tank 13 and the mixture charging unit 12. And it is implement | achieved by the hole formed so that the opening amount could be adjusted. The amount of opening may be adjusted by opening a plurality of holes and closing some of them, or the size of the hole itself may be adjusted. Further, the opening amount may be adjusted by both of them.

  By the liquid level adjusting means 6, the liquid level 9 of the wetting liquid in the mixture charging unit 12 is adjusted to be lower than the liquid level of the wetting liquid 4 in the wetting liquid storage tank 13. By adjusting the height of the liquid level 9 of the wetting liquid in the mixture charging unit 12 in this way, a polyolefin-based plastic composition having a lighter specific gravity and less likely to sink than the wetting liquid 4 can be easily and efficiently supplied to the pump 7. Sucked.

  The wetting liquid storage tank 8 is a box provided separately from the wetting liquid storage tank 13, and as described above, the mixture and the wetting liquid 4 in the mixture charging unit 12 are supplied via the pump 7 and the pipe 5. Is transported inside. A discharge port 8a is provided at the bottom of the wetting liquid storage tank 8, and the mixture and the wetting liquid 4 are discharged from the discharge port, and the mixture after being exposed to the liquid atmosphere as the wetting liquid can be exposed to a gas atmosphere. It is configured to be able to.

  According to the separation and recovery apparatus of the present invention, by having the wetting means 1 as described above, the step of exposing the mixture to the wetting liquid 4 (that is, the liquid atmosphere) and then to the gas atmosphere is automatically performed. It becomes possible. When the mixture is exposed to a liquid atmosphere, bubbles are generated in the surface of the mixture where water is difficult to penetrate due to the presence of pores and the like. In this way, by exposing a mixture of bubbles on the surface where water is difficult to permeate to a gas atmosphere, the bubbles burst, but the pressure in the bubbles is higher than the atmospheric pressure. Water spreads on the surface. For this reason, there exists an advantage that water becomes easy to osmose | permeate also to the surface of the plastic waste material into which water does not osmose | permeate easily by presence of a pore.

  The wetting liquid used in the separation and recovery apparatus of the present invention is not particularly limited, but it is preferable to use water. By using water, it is possible to obtain the liquid itself at a low cost, and there are advantages that waste water treatment can be easily performed at a low cost. The liquid may be a solution in which NaCl or other organic or inorganic substance is dissolved in water, or a mixed solution thereof.

  The wetting means 1 in the separation and recovery apparatus of the present invention preferably further comprises means for separating the mixture and the wetting liquid conveyed using the pump. In the example shown in FIG. 1, the case where it has the conveyance means 11 which can isolate | separate the mixture and the wetting liquid which were supplied from the wetting liquid storage tank 8 is shown. The transport means 11 is preferably configured to separate the mixture and the wetting liquid while transporting, and at the same time to expose the separated mixture to a gas atmosphere. Such a conveying means 11 can be realized by using, for example, a belt conveyor (preferably a mesh belt conveyor).

  When a mesh belt conveyor is used as the conveying means 11, it is preferable to use one having a mesh of 1 to 6 mm (more preferably 2 to 4 mm). If the mesh size exceeds 6 mm, the ratio of the small particle size falling from the mesh in the mixture increases, and the mixture is returned to the mixture input unit 12 through the wetting liquid recovery means 10 together with the wetting liquid. Even if it is less than 1 mm, the separation ability of the mixture and the wetting liquid is not greatly affected, but there is a demerit that the price of the mesh belt is increased and a motor having a larger torque is required. Moreover, the conveyance time required for conveyance to the specific gravity separation means which is the next step is not particularly limited, but is preferably 5 to 60 seconds (more preferably 10 to 30 seconds). If the conveying time is shorter than 5 seconds, the mixture and the wetting liquid tend not to be sufficiently separated. Even if the conveying time is longer than 60 seconds, the separation ability of the mixture and the wetting liquid is not improved. As the mesh belt conveyor having the above-mentioned range, specifically, a water-resistant belt conveyor with a sun FB2S-OD-109-190-100DC25 (manufactured by Maruyasu Machinery Co., Ltd.) can be preferably used.

  In the separation and recovery apparatus of the present invention, it is preferable that the width of the discharge port 8a of the wetting liquid storage tank 8 and the width of the transport means (length in a direction perpendicular to the transport direction) are designed to be approximately the same. As a result, the width of the conveying means 11 can be sufficiently used to diffuse the mixture, and the mixture can be easily and efficiently exposed to air.

  It is preferable that the transport means 11 is installed so as to have an inclination that goes upward as it goes in the transport direction so that the wetting liquid and the mixture can be separated easily and efficiently. The conveying means 11 is installed with an inclination so that an angle formed between the horizontal direction and the conveying direction (angle θ in FIG. 1) is preferably 5 ° to 45 °, more preferably 10 ° to 20 °. If the angle θ of the conveying means 11 is less than 5 °, the wetting liquid and the mixture tend not to be sufficiently separated, and if the angle θ exceeds 45 °, the mixture spills from the upstream side of the conveying means 11. This is because there is a possibility that the mixture may fall or the mixture cannot slide down on the conveying means 11 and be conveyed.

  In the separation and recovery apparatus of the present invention, the conveying means 11 is preferably installed above the pump 7, and more preferably installed above the mixture charging unit 12. Since the conveying means 11 is installed above the pump 7 (more preferably, the mixture charging unit 12), the separated wetting liquid can be easily and efficiently returned to the pump 7, and the wetting liquid can be circulated cyclically. Can be used.

  Here, FIG. 2 is a diagram schematically showing another preferred embodiment of the separation and recovery apparatus of the present invention. As shown in FIG. 2, the separation and recovery apparatus of the present invention also allows the mixture and the wetting liquid 4 conveyed using the pump 7 to be directly carried out to the conveying means 11 (that is, the wetting liquid). It may be configured not to go through the storage tank 8). In this case, it is preferable that the outlet for the mixture and the wetting liquid is provided above the conveying means 11 and that the carrying-out direction of the mixture and the wetting liquid is substantially parallel to the conveying direction of the conveying means 11. Accordingly, the mixture can be diffused on the transport unit 11 by using the width of the transport unit 11 sufficiently, and the mixture can be easily and efficiently exposed to the gas atmosphere (air).

  The separation / recovery device of the present invention preferably further comprises a wetting liquid recovery means 10 for recovering the wetting liquid separated by the transport means 11. In the example shown in FIG. 1, the wetting liquid recovery means 10 is installed so as to cover the entire area in the conveyance direction of the conveyance means 11 below the conveyance means 11 and above the mixture charging unit 12, and is separated by the conveyance means 11. The liquid is collected and can be charged into the mixture charging unit 12. By further including such a wetting liquid recovery means 10, it is possible to circulate and use the wetting liquid without waste.

  In the separation and recovery apparatus of the present invention, the mixture (wet mixture) separated from the wetting liquid 4 while being transported by the transport means 11 is put into the specific gravity separation means 2. The specific gravity separation means 2 includes a specific gravity separation liquid storage tank 25 in which a specific gravity separation liquid 24 is accommodated, and a wet mixture feeding section 23 for feeding the mixture conveyed by the conveyance means 11 into the specific gravity separation liquid storage tank 25. Prepare. The wet mixture charged into the specific gravity separation liquid storage tank 25 is separated into specific gravity of a low specific gravity product and a high specific gravity product.

  As the specific gravity separation liquid, for example, when the polyolefin plastic composition is separated and recovered, the specific gravity of the specific gravity separation liquid is preferably 0.92 or more, more preferably 0.95 or more. The specific gravity is preferably 1.01 or less, and more preferably 1.00 or less. When this specific gravity is less than 0.92, a part of the polyolefin plastic tends to settle and the recovery rate decreases, and when this specific gravity exceeds 1.01, a part of the polystyrene plastic is mixed. This is because there is a tendency. Here, the specific gravity separation liquid having a specific gravity of 0.92 or more and 1.01 or less is not particularly limited, but is preferably water.

  Furthermore, for example, when separating and recovering other types of plastic compositions other than polyolefin-based or polystyrene-based, the specific gravity of the specific gravity separation liquid is preferably 1.00 or more, particularly 1.01 or more. Is more preferable. The specific gravity is preferably 1.10 or less, more preferably 1.08 or less. When this specific gravity is less than 1.00, there is a tendency that polyolefin-based plastics are mixed, and when this specific gravity exceeds 1.10, there is a tendency that polyamide-based, polycarbonate-based, rubber and the like are mixed. Here, the specific gravity separation liquid having a specific gravity of 1.10 or less and 1.00 or more is not particularly limited, but is preferably a solution in which NaCl is dissolved in water. Alternatively, a solution in which other organic or inorganic substances are dissolved or a mixed solution thereof may be used.

  Furthermore, when the plastic waste material is separated and recovered into three plastic compositions, ie, a polyolefin-based plastic composition, a polystyrene-based plastic composition, and another series of plastic compositions, the specific gravity is 0.92 or more and 1.01. It is preferable to use two types of the following liquids and specific gravity separation liquids of 1.10 or less and 1.00 or more. At this time, although the order is not particularly limited, a polyolefin plastic composition and a polystyrene plastic composition, and other series of plastic compositions using a specific gravity separation liquid having a specific gravity of 1.00 or more and 1.10 or less. It is desirable to separate the polyolefin plastic composition and the polystyrene plastic composition using a specific gravity separation liquid having a specific gravity of 0.92 or more and 1.01 or less.

  1 and 2 show examples in which the mixture contains a polyolefin-based plastic composition and water is used as a specific gravity separation liquid. In this case, the polyolefin-based plastic composition is separated from the other series of plastic compositions (high specific gravity) as a low specific gravity product.

  In the separation and recovery apparatus of the example shown in FIGS. 1 and 2, the specific gravity separation liquid storage tank 25 is provided with a low specific gravity material transport means 22 for carrying out a low specific gravity material near the liquid surface of the specific gravity separation liquid 24, and A high specific gravity transport means 26 is provided for transporting the high specific gravity from the bottom of the specific gravity separation liquid 24 to the outside of the specific gravity separation liquid storage tank 25. Each of the low specific gravity transport means 22 and the high specific gravity transport means 26 is formed by, for example, a belt conveyor, and is provided so as to incline upward toward the front in the transport direction. A low specific gravity collection container 21 is provided in front of the low specific gravity transport means 22 in the transport direction, and a high specific gravity collection container 27 is provided in front of the high specific gravity transport means 26 in the transport direction. The low specific gravity material and the high specific gravity material separated in each are collected.

  The separation and recovery apparatus of the present invention described above can be suitably used for a mixture separation and recovery method. Here, the mixture separated and recovered according to the present invention is desirably a crushed product of a used product including a plastic member. Here, the used product including the plastic member is recommended to be a product selected from the group consisting of an air conditioner, a television, a refrigerator, and a washing machine.

  Here, the composition ratio of the plastic composition of the plastic-based crushed material collected from the air-conditioner, television, refrigerator, and washing machine (referred to as “four items of home appliances” in this specification) discarded as used products. A typical example of the specific gravity will be described with reference to Table 1 and Table 2.

  Table 1 shows a typical example of the composition ratio of each plastic composition used for plastic members collected from four items of household appliances. Table 2 shows a typical example of the range of specific gravity of the plastic composition by main system.

  As is clear from Table 1, in plastic members recovered from four items of home appliances, if plastic members made of polyolefin plastic compositions and polystyrene plastic compositions can be material recycled, the plastic members of four items of home appliances can be recycled. It can be said that the recycling rate exceeds 60%.

  Further, as is clear from these tables, it can be seen that the specific gravity range of the polyolefin-based plastic composition used in a large amount for the four home appliances is generally included in the range of 0.89 to 0.91. Moreover, it turns out that the range of specific gravity of a polystyrene-type plastic composition is generally contained in the range of 1.04-1.05. And it turns out that the specific gravity is mostly contained in the range of 1.10-2.00 generally for the member consisting of the plastic composition of another system | strain.

  Here, in the present specification, the term “plastic composition” refers to not only a plastic composition in a narrow sense but also a plastic composition in a broad sense including a rubber composition and a polymer composition. It shall be shown.

  From the above, in general, by using a separation liquid having a specific gravity in the range of 1.06 to 1.10, members made of a polyolefin plastic composition and a polystyrene plastic composition, and other systems It turns out that it is possible to isolate | separate from the member which consists of a plastic composition. From the above, generally, by using a separation liquid having a specific gravity in the range of 0.92 to 1.01 (particularly, a separation liquid having a specific gravity in the range of 0.95 to 1.00), It can be seen that a member made of a plastic composition and a member made of a polystyrene-based plastic composition can be separated.

  FIG. 3 is a flowchart showing a preferred example of a method for separating and recovering a mixture using the separation and recovery apparatus of the present invention. Hereinafter, a method for separating and recovering a mixture using the separation and recovery apparatus of the present invention will be described in detail with reference to FIG.

  In this specific example, first, as shown in FIG. 3, four used home appliances discarded from homes and the like are collected (step 101). Then, the four items of household appliances are dismantled, and large metal parts such as compressors and heat exchangers, and large plastic molded articles such as water tanks for washing machines and vegetable cases for refrigerators are collected for each part ( Step 102).

  Next, the remaining members of the waste of the four home appliances from which the large metal members and the like have been collected are roughly crushed by a large crusher such as an impact crusher or a shear crusher (step 103). The particle size of the crushed material in step 103 is not particularly limited, but is preferably 10 mm or more, and more preferably 40 mm or more. Moreover, it is preferable that the particle size of a crushed material is 80 mm or less, and it is more preferable that it is 60 mm or less. If the particle size of the crushed material is less than 10 mm or more than 80 mm, the metal selection accuracy in the next process tends to be reduced, and if the particle size is less than 10 mm, it takes a long time for crushing. The plastic tends to melt or undergo thermal oxidative degradation, and when the particle size exceeds 80 mm, the bulk specific gravity tends to be small and the workability in the subsequent processes tends to be adversely affected. Specifically, it is particularly preferable to crush so that the particle size is about 60 mm. In addition, members that are difficult to crush, such as a large metal member such as a compressor and a heat exchanger, may be disassembled in advance and removed from the waste including the plastic member.

  Subsequently, the waste crushed materials of the four home appliances are sorted into metal crushed materials and plastic crushed materials formed of iron, copper, aluminum, etc. (step 104). In order to sort the crushed waste in this step into metal crushed material and plastic crushed material, for example, a sorting device using magnetic force suitable for iron sorting, eddy current suitable for sorting aluminum and copper is used. The sorting device used, the trommel device for uniforming the particle size and sieving can be suitably used.

  Next, it is preferable to further sort the low bulk specific gravity crushed material from the plastic crushed material after sorting the metal crushed material (step 104) (step 105). Here, the low bulk specific gravity crushed material means a crushed material having a bulk specific gravity of 0.3 or less. Specific examples of the low bulk specific gravity crushed material include a polyurethane heat-insulating material crushed material and a polystyrene foam-based crushed material. This low bulk specific gravity crushed material can be sorted by, for example, a sorting device using wind power or a device using a vibrating screen. When sorting the crushed waste into metal-based crushed material, plastic-based crushed material and low-bulk specific gravity crushed material, when sorting by wind, magnetic force, or eddy current, the order Is not particularly limited, but from the viewpoint of sorting efficiency, first, iron-based metal crushed material is separated by magnetic force, then eddy current is used to sort aluminum-based metal or copper-based metal crushed material, followed by It is preferable that the low bulk specific gravity crushed material is sorted by wind and the remaining mixed plastic crushed material is subjected to the following steps.

  The mixed plastic-based crushed material obtained above is subjected to a fine crushing step (step 106). This fine crushing can be performed using, for example, a shearing type crushing apparatus (the one after the fine crushing is hereinafter referred to as “finely crushed material”). Although there is no restriction | limiting in particular in the magnitude | size of a finely crushed material, It is preferable that it is 5 mm or more, and it is more preferable that it is especially 8 mm or more. The particle size is preferably 30 mm or less, particularly preferably 20 mm or less. If this particle size is less than 5 mm, it takes a long time for crushing, so the plastic tends to melt or undergo thermal oxidative degradation. If this particle size exceeds 30 mm, the workability in the thermoforming process is adversely affected. This is because there is a tendency to exert an effect. Moreover, even when the particle size is less than 5 mm or more than 30 mm, there is a tendency to adversely affect the sorting ability of the wet specific gravity separation process which is the next and subsequent steps.

  In addition, the large plastic molded articles such as the water tank and the vegetable case of the refrigerator collected by the manual dismantling (step 102) are directly subjected to the fine crushing step (step 106) without going through the steps 103 to 105 described above. It may be provided.

  Subsequently, after the step of exposing plastic waste composed of a plurality of types of plastics to a liquid atmosphere (step 107), a step of exposing to a gas atmosphere is performed (step 108). The above-described separation / recovery device of the present invention can be suitably used to perform the steps after Step 107. That is, steps 107 and 108 can be automatically performed by the wetting means 1 of the separation and recovery apparatus of the present invention.

  Then, the plastic waste exposed to the gas atmosphere is transferred to the wet specific gravity separation process (step 109). By doing so, wet specific gravity sorting can be performed without bubbles adhering to the surface of the plastic waste material, and more specific gravity sorting can be performed. Such a wet specific gravity separation step can be automatically performed by the specific gravity separation means 2 of the separation and recovery apparatus of the present invention described above.

  Then, the plastic waste material selected for each system by the wet specific gravity separation process is molded into a plastic raw material for molding (step 110), and this plastic raw material is put into an injection molding machine to create a plastic molded body (step 111). Is preferred. Thus, it is preferable to perform material recycling by heat-melting the plastic waste material separated for each system by using the separation and recovery apparatus of the present invention and then molding the plastic waste material into a specific shape.

  Specific examples of plastics that can be recycled include polyolefin-based, polystyrene-based, polycarbonate-based, and polymethylmethacrylate-based plastics. Among these, polyolefin-based plastics such as polyethylene and polypropylene, and polystyrene-based plastics such as polystyrene and ABS, as shown in Table 3, are superior in processability and economy compared to other plastics. Therefore, material recycling can be suitably performed using the separation and recovery device of the present invention.

  That is, the plastic waste material separated and recovered using the separation and recovery device of the present invention is at least one selected from the group consisting of a polyolefin plastic composition, a polystyrene plastic composition, and other series of plastic compositions, The specific gravity of the polyolefin plastic composition is in the range of 0.85 to 1.00 (more preferably 0.89 to 0.91), and the specific gravity of the polystyrene plastic composition is 1.00 to 1.08. (More preferably 1.04 to 1.05), and the specific gravity of most of the other series of plastic compositions is 1.08 to 2.00 (more preferably 1.10 to 2.00). It is preferable that it exists in the range. Moreover, it is preferable that the material to be collected in the present invention is a polyolefin-based plastic composition and / or a polystyrene-based plastic composition and / or other series of plastic compositions.

  Here, when the melting point of the plastic is T ° C., the heating temperature at this time is preferably T ° C. or higher, and more preferably (T + 10) ° C. or higher. Further, the heating temperature at this time is preferably (T + 120) ° C. or less, and more preferably (T + 80) ° C. or less. If the heating temperature at this time is less than T ° C., the plastic does not melt sufficiently, and there is a tendency that it is difficult to mold. If the heating temperature at this time exceeds (T + 120) ° C., the plastic is thermally deteriorated. There is a tendency to do.

  In the method for separating and collecting a mixture using the separation and recovery apparatus of the present invention, steps not shown in FIG. 3 may be added or deleted as necessary. In the present invention, steps 101 and 102 may be omitted, and the plastic waste material may be subjected to a rough crushing step (step 103) or a fine crushing step (step 106).

  The present invention also provides a plastic raw material production method using the above-described separation and recovery apparatus of the present invention, and a plastic raw material obtained by the production method. The plastic raw material of the present invention is preferably in the form of pellets. At this time, the particle diameter of the pellet is preferably 1 mm or more, and more preferably 2 mm or more. Further, the particle diameter of the pellet is preferably 8 mm or less, and more preferably 5 mm or less. When the particle size of the pellet is less than 1 mm, there is a tendency that workability is lowered because it floats. When the particle size of the pellet exceeds 8 mm, the pellet does not melt sufficiently in the cylinder of the molding machine, so that uniform mixing This is because they tend not to be.

  In addition, when shape | molding a pellet-shaped plastic raw material, you may granulate by any methods, such as a sheet cut, a strand cut, a hot air cut, and an underwater cut, after extrusion molding. Among these granulation methods, when forming into a specific shape by injection molding later, an underwater cut that can smoothly supply a resin raw material and can cope with a large amount of processing is particularly preferable.

  In addition, the shape of the plastic raw material of the present invention is not particularly limited to a pellet form, and may be any form such as a sheet form, a film form, a pipe form, etc. What is necessary is just to determine suitably from an aspect or the characteristic calculated | required.

  Furthermore, additives such as heat stabilizers, light stabilizers, antistatic agents, lubricants, fillers, copper damage inhibitors, antibacterial agents, and coloring agents are added to the plastic raw material of the present invention, and the effects of the present invention can be achieved. You may add in the quantity of the range which does not harm.

  Furthermore, the present invention also provides a method for producing a plastic molded article using the above-described separation and recovery apparatus of the present invention, and a plastic molded article produced by the production method. The plastic molded body produced by the method of the present invention may be a plastic member. In this case, the plastic member is preferably used for a product selected from the group consisting of an air conditioner, a television, a refrigerator, and a washing machine.

  The plastic member can be molded from the above plastic raw material using a method such as injection molding. Although it does not specifically limit as an injection molding machine used at this time, For example, a screw in-line type injection molding machine, a plunger type injection molding machine, etc. are mentioned.

  In order to further simplify the molding step of the plastic member, the crushed plastic is directly put into an injection molding machine without producing a plastic raw material having a shape such as a pellet, and the plastic member is directly added. It may be produced.

  Furthermore, this plastic member may contain additives such as heat stabilizers, light stabilizers, antistatic agents, lubricants, fillers, copper damage inhibitors, antibacterial agents, colorants, etc. It may be produced by adding the amount in a range not to be formed. The step of adding these additives is preferably performed when the plastic raw material or the crushed plastic is put into an extrusion molding machine or an injection molding machine.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to these.

<Example>
According to the procedure of FIG. 3, the polyolefin-based plastic composition contained in the experimental material was separated and recovered. In addition, after obtaining an air-conditioner, a television, a refrigerator, and a washing machine as a product including a molded body made of a plastic composition, the experimental material was manually disassembled using the product as waste (step 102). Crushed material obtained by rough crushing using a normal crusher (step 103) is used to sort metal crushed material with a sorter using normal magnetic force (step 104), and further using normal wind power. The low bulk specific gravity crushed material was sorted by a sorter (step 105). In this manner, the remaining plastic mixture obtained by removing the metal-based crushed material and the low bulk specific gravity crushed material from the crushed material was prepared by finely crushing using a normal crusher (step 106).

  The experimental material prepared as described above is fed into the wetting liquid 4 in the wetting liquid storage tank 13 through the mixture feeding unit 12 using the separation and recovery apparatus of the present invention shown in FIG. The step of exposing to a liquid atmosphere (step 107) and the step of exposing to a gas atmosphere (step 108) were performed by discharging to the conveying means 11 through the pipe 5 and the wetting liquid storage tank 8. Water was used as the wetting liquid, and a submersible pump was used as the pump 7. In addition, the mixture charging unit 12 was configured such that the wetting liquid therein formed a cyclone flow. As the transport means 11, a mesh belt conveyor (waterproof belt conveyor with sun FB2S-OD-109-190-100-DC25 (manufactured by Maruyasu Machinery Co., Ltd.), scale: 3 mm) is used, and an angle θ (horizontal direction and transport direction) Was set at 15 °.

  Thereafter, the wet mixture conveyed by the conveying means 11 was supplied to the specific gravity separation means 2 to perform a specific gravity separation step (step 109). As the specific gravity separation liquid, water having a specific gravity of 1.0 was used. As a result, the mixture was separated into a low specific gravity product and a high specific gravity product, and the polyolefin-based plastic composition contained in the mixture was recovered as a low specific gravity product in the low specific gravity material container 21 by the low specific gravity material conveying means 22. . Further, the plastic compositions of other systems other than the polyolefin-based plastic composition in the mixture were recovered in the high specific gravity container 27 by the high specific gravity transport means 26.

  Next, the polyolefin plastic composition recovered in the low specific gravity container 21 is dehydrated and dried, and then melt-kneaded at 230 ° C. using a twin-screw melt kneader / extruder having a screw diameter of 45 mm to obtain a pellet-shaped plastic raw material. Created.

  Next, the produced plastic material in the form of pellets was put into a hopper with a 10-ton injection molding machine and molded under injection molding conditions of a molding temperature of 230 ° C. and a mold temperature of 40 ° C. to produce a plastic molded body.

It is a figure which shows typically the separation-and-recovery apparatus of a preferable example of this invention. It is a figure which shows typically the separation / recovery apparatus of the other preferable example of this invention. It is a flowchart which shows a preferable example of the separation / recovery method using the separation / recovery device of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Wetting means, 2 Specific gravity separation means, 4 Wetting liquid, 5 Piping, 6 Liquid level adjustment means, 7 Pump, 8 Wetting liquid storage tank, 10 Wetting liquid collection | recovery means, 11 Conveyance means, 12 Mixing part, 13 Wetting liquid storage Tank, 22 Low specific gravity transport means, 24 Specific gravity separation liquid, 25 Specific gravity separation liquid storage tank, 26 High specific gravity transport means.

Claims (30)

A mixture composed of a plurality of materials having different specific gravities is exposed to a wetting liquid, and then exposed to a gas atmosphere. A separation / recovery device for a mixture composed of a plurality of types of materials having different specific gravities, comprising specific gravity separation means for separating into specific gravity materials,
A separation and recovery device, wherein a pump is disposed in the wetting means.   The separation and recovery device according to claim 1, wherein the pump is capable of stirring the mixture and the wetting liquid and transporting the mixture together with the wetting liquid.   The separation / recovery device according to claim 1, wherein the pump is a submersible pump.   The separation / recovery device according to any one of claims 1 to 3, wherein the wetting means has a conveying means capable of separating the mixture and the wetting liquid conveyed using the pump.   The separation and recovery device according to claim 4, wherein the conveying unit is configured to separate the mixture and the wetting liquid and simultaneously expose the separated mixture to a gas atmosphere.   The separation and recovery apparatus according to claim 4 or 5, wherein the transport unit is inclined at an angle of 5 ° to 45 ° so as to go upward as it goes in the transport direction.   A wetting liquid storage tank for storing the mixture and the wetting liquid transported using the pump, and supplying the mixture and the wetting liquid from the wetting liquid storage tank to the transporting unit. The separation / recovery device according to claim 4, which is configured.   The separation and recovery device according to any one of claims 4 to 6, wherein the mixture and the wetting liquid transported using the pump are configured to be directly transported to the transporting means.   The separation and recovery apparatus according to claim 4, wherein the wetting unit further includes a recovery unit for recovering the wetting liquid separated by the transport unit.   The separation and recovery device according to any one of claims 4 to 9, wherein the conveying means is installed above a pump.   The pump is disposed in a wetting liquid storage tank that contains a wetting liquid therein, and in the wetting liquid storage tank, a mixture charging unit for charging the mixture into the pump is disposed. The separation / recovery device according to any one of claims 1 to 10, wherein the inside of the mixture charging part and the inside of the wetting liquid storage tank communicate with each other so that the wetting liquid can pass therethrough.   The separation / recovery device according to claim 11, further comprising liquid level adjusting means for adjusting a liquid level height of the wetting liquid in the mixture charging unit.   At least one liquid level adjusting means is installed at a height near the liquid level of the wetting liquid in the wetting liquid storage tank and at which the wetting liquid continuously flows from the wetting liquid storage tank into the mixture charging unit. The separation and recovery device according to claim 12, wherein   The separation / recovery device according to any one of claims 11 to 13, wherein the charged mixture and the wetting liquid form a cyclone flow in the mixture charging portion.   The separation and recovery device according to any one of claims 11 to 14, wherein a part of the mixture charging portion is formed in a substantially conical shape.   The separation and recovery device according to any one of claims 11 to 15, wherein a liquid level height of the wetting liquid in the mixture charging unit is adjusted to be lower than a liquid level height of the wetting liquid in the wetting liquid storage tank.   The separation / recovery device according to any one of claims 11 to 16, wherein the wetting liquid recovered by the recovery means is input into the mixture input part.   The separation / recovery device according to claim 1, wherein the wetting liquid is water.   The separation and recovery device according to any one of claims 1 to 18, wherein the mixture includes plastic waste material composed of a plurality of types of plastics.   The separation / recovery device according to claim 19, wherein the plastic waste material is a plastic molded body or a crushed product of the product including the plastic molded body.   The separation and recovery device according to claim 20, wherein a particle size of the crushed material is 5 to 30 mm.   The separation / recovery device according to claim 20 or 21, wherein the product including the plastic molded body is a product selected from the group consisting of an air conditioner, a television, a refrigerator, and a washing machine.   The separation and recovery apparatus according to any one of claims 19 to 22, wherein the plastic waste material is at least one selected from the group consisting of a polyolefin-based plastic composition, a polystyrene-based plastic composition, and other series of plastic compositions.   The separation / recovery device according to any one of claims 19 to 23, wherein the polyolefin-based plastic composition and / or the polystyrene-based plastic composition and / or other series of plastic compositions are separated and recovered.   A method for producing a plastic raw material using the separation and recovery device according to any one of claims 1 to 24.   The manufacturing method of the plastic molding using the separation collection | recovery apparatus described in any one of Claims 1-24.   The plastic raw material manufactured by the method of Claim 25.   The plastic raw material according to claim 27, which is in a pellet form.   A plastic molded article produced by the method according to claim 26.   30. The plastic molded article according to claim 29, which is used for a product selected from the group consisting of an air conditioner, a television, a refrigerator, and a washing machine.

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