Note: Pay attention to the size and shape of the separator Scope of application: suitable for separation between plastics with large density difference Type of wind screen separation device: 1. Vertical: Generally, it is a zigzag or similar cylindrical device. Air is blown from the bottom and the material is separated in the middle of the cylinder. Equipment of different shapes and different wind speeds can separate materials by type, and those who are lighter from the top are discharged from the bottom. 2, horizontal: a rectangular container, divided into several hoppers, the air is blown horizontally from the side, the waste is put from the top, the heavy one falls into the near hopper, the light is blown by the airflow to the far away, the flow of water into the hopper, each Drain from the bottom. 3. Vortex type: The air is blown into a vortex that is radiated, and the waste is sent from the side to form a vortex, and the light is taken out from above, and the heavy one is discharged deep into the bottom. Application extension: The word separation device can also be used in combination with vertical and eddy current, together with pulverization, magnetic separation, vibrating screen, etc. to form a combined system of wind screen separation. Waste plastic electrostatic separation Separation characteristics: firstly dry the waste plastic, pulverize into 10 square millimeters, preferably less than 6 square millimeters; add 1*10^-6 grade modifier and surfactant to improve its frictional chargeability; Strongly stirred to make it frictional and charged, different plastics produce opposite charges. Scope of application: The greater the difference in charge generated by friction, the better the separation effect and the higher the efficiency. This method is most suitable for the separation of a mixture of only two plastics. Only polyvinyl chloride is easily separated from a wide variety of mixtures because polyvinyl chloride is always negatively charged relative to other plastics. Separation device characteristics: There are two baffles on the bottom of the device, which can return the uncharged plastic particles back to the device for separation. Waste plastic density separation This is a method of separating and separating different plastics with different densities, and there are two methods of static separation and hydrocyclone separation. Static separation Separation characteristics: Separation of the plastics of different densities in a specific density of liquid. Scope of application: It is suitable for the separation of varieties with large density difference, but it is difficult to obtain high purity isolates for the separation of similar density. Common separation liquid: water, saturated saline solution, 58.4% alcohol solution, 55.4% alcohol solution and calcium chloride aqueous solution. Note: When water is used as the density separation liquid, some of them will float on the water surface due to the difference in the beginning and surface activity of the plastic, which will affect the separation effect. At this point, it is necessary to use a surfactant for pretreatment to fully infiltrate Hydrocyclone separation Separation characteristics: The use of a hydrocyclone and a floatation method can effectively separate plastics having a density greater than and less than 1 g/cm3. The thickness is preferably greater than 3 mm and the difference in density is about 0.5 g/cm3. If a flat bottom separator is used, various plastics having a density greater than 1 g/cm3 can be separated. Multi-stage separation works better. The separation step of the hydrocyclone: ​​ethically smash the waste plastic, then clean and pre-treat, suck the material in the hopper into the storage waste, the waste is evenly dispersed in the tank, and is fed into the hydrocyclone at a fixed speed by a centrifugal pump. . The plastic with a small density is discharged from the upper part, collected, and dehydrated by a vibrating screen. The separated water can be recycled. Manual sorting of waste plastics Separation characteristics: Separation and screening of waste plastics, the simplest method is manual sorting. Although it is time-consuming and laborious and low in efficiency, it is the most primitive method, but it is still widely used, especially on the feed conveyor belt for some easy to be found. And sorted impurities. The division and sorting method is most suitable for sorting waste paper, cards, glass containers and other items. Sorting steps: 1, the metal and non-metallic impurities removed by the naked eye can see a variety of impurities 2, for the waste plastics first product classification, can be divided into agricultural film, natural packaging film, variegated packaging film, foam plastic, sandals, slippers, soles, corner scraps, packaging foam blocks, beverage bottles, various packaging containers Wait. 3. According to the resin variety, the polyethylene, polypropylene, polyvinyl chloride, polystyrene, nylon, polyurethane and polyester are separated. Appearance trait identification and combustion identification are usually used. 4. Sort the waste plastics that have been classified according to color and quality. The colors can be divided into black, red, brown, blue, green, yellow and colorless, etc., to eliminate inferior waste plastic products such as serious pollution, blackening and burning. . Waste plastic melt separation Separation characteristics: Separation using different melting temperatures of plastics. The method comprises placing the mixed waste plastic on a conveyor belt and passing through a heating chamber at a lower melting temperature of the plastic. The plastic is melted and attached to the conveyor belt and collected by mechanical means; the unmelted plastic continues to run through the higher one. The heating chamber on the melting temperature of the grade plastic separates the plastic in the same way. This continues, and finally the last melted plastic is collected at the conveyor end. Waste plastic temperature difference separation Separation characteristics: The mixture is selectively embrittled and pulverized by different embrittlement temperatures of various plastics to realize plastic separation. Scope of application: This method is most suitable for the separation of polyvinyl chloride and polyethylene mixture, because the embrittlement temperature of polyvinyl chloride is -41 ° C, and the embrittlement temperature of polyethylene is below -100 ° C. In addition, it can also be used for the separation of polyvinyl chloride and PET bottles. Application example: Separation of polyvinyl chloride and polyethylene mixture: first put the mixed material into the cooler, cool it to -50 ° C, then send it to the pulverizer for pulverization, crushed by the embrittlement of polyvinyl chloride, and then screened. Separate from unpulverized polyethylene. Waste PE, PP, PET sorting Separation characteristics: Put it into the pool first. Since PET has the highest density and its relative density is 1.30--1.38, PET will sink. Then, start pouring alcohol into the pool, neutralize the density of the water, and adjust the density to 0.91. When the PE in the water sinks, it is adjusted. Separation principle: The density method is used to separate the mixture of PP, PE and PET. The density of PP is 0.89--0.91, the density of PE is 0.91---0.965, and the density of PET is 1.30--1.38. Waste metal and plastic separation Metal trap The pulverized waste is piped, and metal scraps having a diameter of 0.75 to 1.2 mm are separated using a metal trap during the transfer. Electrostatic separator The mixed material is pulverized and put into an electrostatic separator, and metal such as copper or aluminum can be separated by using different charging characteristics of metal and plastic. This method is applicable to the treatment of metal-filled composite materials, cable materials and metal-plated plastics. Dissolution separation The plastic coated metal part is immersed in a suspension containing methylene chloride, a nonionic surfactant, paraffin and water to dissolve and separate the plastic coating. Brittle separation The metal and plastic hybrid waste is cooled to the embrittlement temperature of the plastic, and then pulverized, and the metal is separated from the plastic by the wind screen separation method. Stripping of cable sheath The outer skin materials of wires and cables mainly include polyvinyl chloride, polyethylene (including cross-linked polyethylene), synthetic rubber and natural rubber. In addition to the above electrostatic separation method, there are two methods of dry and warm methods to make plastic and rubber. Effective separation from copper and aluminum core wires. (1) Dry separation: The inside of the cable is uniformly heated by a far-infrared device, and the outer skin is manually peeled off. (2) Wet separation: The aluminum wire is immersed in a solution of a penetrating agent (surfactant), heated to 70-90 degrees, and then peeled off the skin, and then continuously washed with an organic solvent several times to completely remove the tar. Waste paper and plastic separated There are three methods for separating paper and plastic: thermal separation, wet separation and electric separation. Separation characteristics of heat separation method: a method of changing paper quality by heating to achieve paper-plastic separation. Divided into two methods: hot tube method and hot air method. Hot tube method The separating device is composed of an electric heating chrome-plated cylinder and a built-in hollow cylinder (drum) with a scraper. The scraper is connected to the wall of the heating cylinder, and the two are reversely rotated, and a trough is connected to the bottom of the cylinder. The material is added from the feed, and the plastic component is melted upon contact with the hot cylinder, adheres to the wall of the cylinder, is scraped off with a scraper, and falls into the trough. This method can separate more than 90% of the plastic from the paper. The separated plastic has a small amount of paper and can be controlled below 1%. Hot air flow method The separation of the plastic film from the paper is achieved by the principle that the plastic film shrinks with heat and reduces the specific area. The film and paper mixture is sent to a heating zone, which may be an agricultural grain dryer, in the form of granules, thereby reducing its surface area, and then feeding it to the air separator, the air stream is a mixture The paper in the strip is taken away and the thermoplastic particles fall on the bottom of the separator. This method can completely separate plastic from paper. Wet separation separation characteristics: The lightweight material obtained from the dry separation separation equipment is sent to a crusher, and the crushed pulp flows out from the small holes in the sorting plate, and the remaining plastic is discharged from a separation outlet. Then, it is sent to a dehydrator for dehydration, and then sent to an air separator for separation. Separation characteristics of electric method: the mixture of paper and plastic is fed into the separator by a vibrating feeder, dropped into a rotating grinding drum, and then sent to a corona zone formed by the wire electrode and the crushing, paper It is attracted to the electrode, and the plastic is still attached to the drum, and collects as the drum rotates plastically to the bottom. When using this method, the humidity has a great influence on the separation result. When the humidity of the mixture is 15%, although the paper and the plastic can be separated, the plasticity is still contaminated by a large amount of paper. When the humidity is increased to 50% or more, the humidity can be made. Plasticity and paper are completely separated. Dongguan Hongtao Plastic Hardware Co., LTD , https://www.twisttiemanufacturer.com
Separation characteristics: the pulverized waste plastic is put into the air screen separation device from above, and the air is blown from the lateral direction or the reverse direction. The difference between the resistance of the air flow and the self-weight formed by different plastics and impurities separates the different kinds of plastics. Impurities such as sand and gravel are separated from the plastic.