Look at these two funny characters. Seems like they are stoning in waste. Even though we do not pay much attention, but much staff and especially plastic are thrown away. Senseless to deny that humanity lives in the era of plastic. Although sometimes its role is not understood that fully, there is a great dependence on this material. Plastic is defined as synthetic or semi-synthetic organics and today we have a great variety of plastic kinds with special features and properties. This blog post is about daily used types. The absolute product leader in plastic production is a bag. Low-density polyethylene or LDPE (number 4) is the source. Regardless its popularity it is still not approved on topic of health safety. The sad fact about LDPE is that it is not widely recycled. However furniture items, garbage cans are just a few products of reused low-density polyethylene. Since the production of plastic bags goes only in ascending direction, there is a great need of finding a recycling technology or alternative material. Another example of highly consumed plastic is PET, number one in a triangle (polyethylene terephthalate). Drinking bottles and jars for enormous amount of products are made from it. Its color is transparent and it is well known for absorption of products’ flavor stored inside. Fortunately, PET is widely recycled and the final product is impressive: fiber for clothes, bags and so on. Picture 2 represents the life circle of a PET bottle. PICTURE 2. Life cycle of PET bottles (www.bannercreations.com)
White bottles for milk and juice are also commonly met. HDPE or high-density polyethylene (number 2) is thicker than PET. Majority of this plastic is used in the food industry, but also in chemical as a container for soaps and detergents. After recycling it is almost not used for food production because of poisonous content possibility form the first usage. However, HDPE is useful at home and secondary plastic can be found as fencing and lumber. The recycling process is long and energy consuming. Five steps can be distinguished. The ball kicked off with collection and transportation to recycling units, after which the waste is sorted. Usually the specific plastic types are delivered separately. Here the codes are useful. It is worth noticing that in most cases plastic is sorted according to color as well. Then goes chipping. Machine shreds material into small pieces which are washed with alkaline detergent afterwards in order to erase all remaining dirt and paper labels. These four stages were preparatory. Pieces of plastic are melted down and this melted plastic is formed into thin tubes by an extruder machine. Tubes then are cut into smaller parts and then the pellets are ready. Now the plastic is recycled and new one can be produced References: The Different Types Of Plastics And Their Classifications. Quality logo products. https://www.qualitylogoproducts.com/lib/different-types-of-plastic.htm Recycling plastics. All-recycling-facts. http://www.all-recycling-facts.com/recycling-plastic.html |
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May 2019
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