Plastic is one of those waste that does not decompose under the influence of the environment. Disused plastic products need to be disposed of. Several decades ago, methods of processing plastic products began to be developed. Recycling of raw materials helps to free landfills from plastic waste.
Instructions
Step 1
Methods for recycling plastics and waste from plastic products are divided into two large groups: mechanical and physicochemical. With the mechanical method, the waste is crushed. This forms a plastic crumb or powdery substance, which is then subjected to casting. The physical and chemical properties of the material remain unchanged.
Step 2
Physicochemical processing technologies are very diverse. One of the methods is the destruction of the original plastic raw material, through which the film and fibers are obtained. The remelting method produces pellets for subsequent injection molding. Materials for polymer coatings are usually obtained by the method of reprecipitation from solutions.
Step 3
The most widespread in the industrial processing of plastics is the method of melting raw materials, which is also called the method of tableting or granulation. This method can be "cold" and "hot". Differences in technology practically do not affect the quality of the material obtained during processing. Plastic granules subsequently become the raw material for the production of molded products for a wide variety of purposes.
Step 4
The first stage of plastic processing is the preparation of raw materials. Waste is cleaned of impurities, dried, mixed with additives, if necessary, and prepared for molding. When molding, special equipment is used in the form of shapes or heads. Of particular importance is the choice of a specific processing method, which should take into account the quality of the feedstock and the scope of application of the obtained semi-finished products.
Step 5
Hot granulation involves the melting of plastic waste, after which the substance is forced through round holes on the working surface of the equipment. The result is a tape of plastic, which is crushed by rotating knives into small tablets (granules). The finished "products" are cooled by a strong air flow.
Step 6
Cold granulation is carried out by forcing the material through the perforated plate. After this processing, a plastic tape is also obtained. It is mechanically divided into granules. To prevent the material from heating up during processing, it is cooled with liquid nitrogen.
Step 7
The granules formed during processing are in the form of balls, lenses or cylinders. The dried finished product is packed in bags, after which it is placed in temporary storage or transported to the place of production of plastic products.
