Recycling method and application of waste plastic film in plastic crushing washing line
In plastic crushing washing line,plastic film is a large category of plastic products. It has a wide range of products and generally has a short product life. It is one of the main types of plastic recycling. What about its different types and recycling technologies, applications and markets? For example, agricultural film. With the promotion of mulching film technology, the problem of waste plastic film left in the field has appeared. Agricultural experts pointed out that where plastic film is used to cover crops, waste plastic films scattered in the fields should be cleaned up in time. Because the plastic film is made of a polyethylene material, it is not easy to decompose under natural conditions. If it is left in the soil, it will hinder the extension of crop roots.
Agricultural film
In plastic crushing washing line,agricultural films mainly include mulch film and shed film. The mulch film is mainly PE film. The shed molds include PE, PE/EVA, and PVC film. When recycling, PE and PVC film should be distinguished. Agricultural films are generally dirty. Remove impurities and clean. The recycling method is mainly granulation, and the waste film after cleaning and drying can be directly used to produce plastic products, such as basins, barrels, and plastic flanges, by hot extrusion.
The uses of waste plastic agricultural film recycled pellets are as follows:
(1) PE recycled pellets
PE recycled pellets can be used to produce agricultural film, and can also be used to make fertilizer packaging bags, garbage bags, agricultural recycled water pipes, fences, tree supports, pots, buckets, garbage bins, geotechnical materials, etc.
(2) PVC recycled pellets
PVC recycled pellets can be used to produce packaging films such as heavy packaging bags, agricultural water pipes, shoe soles, etc. The packaging film materials include various composite films. The single-layer packaging film of one material can be directly made into plastic products or granulated into various products after sorting and cleaning, just like agricultural films.
PET film
PET film can be used as packaging, decoration, tape base or capacitor insulation, PET film is also used as a photographic film base, PET is also used in large quantities for fiber. PET industrial waste can also be used as a binder. PET industrial waste can be modified to produce hot melt adhesive, which can be used for bonding flexible materials such as cloth, leather, paper, plastic, aluminum, etc. Waste PET film, sheet or fiber can be made into unsaturated polyester, which can be used to make artificial marble.
Recycling of film “ears”
Plastic film includes PP, PE, PVC and other materials. In the production of heat shrinkable film, cling film, composite film, tape film, flat wire, etc., waste film cut off on both sides of the film will be produced, which is called “ear material”. “. This raw material is crushed into “snowflakes” and added with good materials to continue the production of finished film, which will affect the quality of the finished film. If it is pelletized and reused, it will increase the cost of pelleting and increase the decomposition of raw materials.
The best method is: pass the ear material through a high-pressure roller, crush it into a very hard plastic strip (filament), cut it directly into plastic granules, and send it directly to the feeding port through a conveying pipe. Regularly mix with new materials to form a continuous recycling pattern. It can not only ensure product quality, but also reduce reuse costs, and also save a lot of management links and management costs.
Paper-plastic composite film, the paper-plastic composite film needs to be separated from paper and plastic before recycling. This is also the method of paper-plastic composite separation. The separation equipment is a chrome-plated hollow barrel with electric heating. The barrel is equipped with a blade. In the hollow cylinder, the barrel and the hollow cylinder rotate in opposite directions. The crushed paper-plastic mixture is added to the barrel. The plastic on the heated mixture in the barrel is melted and discharged from the lower part of the barrel. The air in the hollow cylinder Take the exhaust gas away.
Aluminum-plastic composite film, aluminum-plastic composite film such as BOPP/aluminum, PE/aluminum, etc., are used for various food packaging. The used aluminum-plastic composite flexible packaging bag is actually a mixed waste material, which is difficult to recycle. The treatment method abroad is mainly to recover heat by incineration. In China, there are methods to obtain low-grade crude products by burning aluminum and pulverizing and adding fillers, but the effect is not satisfactory. Here is an example of using the conductivity of aluminum to manufacture antistatic functional materials. The process is as follows: aluminum-plastic composite waste-cleaning-crushing-sieving-pellets-aluminum powder-additives-extrusion-semi-finished products-extrusion-finished products . The aluminum-plastic composite waste is cleaned, crushed and sieved through a 10-day sieve, and then pelletized. The pellet process conditions are water spray: 0.8 liters of 95°C water, feeding time: 3 min; pumping time 5 min, crushing time 10 min, and 15 kg each time. The pelletized material is extruded by an extruder to become a semi-finished product. This semi-finished product is then added with 20% aluminum powder, flame retardant, compatibilizer and other additives, and then extruded and pelletized to obtain the product. As a conductive material.