Waste Plastics Collection and Treatment
The main sources of post-consumer or post-use waste plastics are identified as:
- Municipal solid waste (MSW) from household waste and commercial waste
- Construction and demolition waste (C&D)
- Waste from electric and electronic equipment (WEEE)
- Depending on the origin of the waste plastic, there is almost always need for different degrees of sorting, collection and treatment. The focus of this report is largely on MSW, while C&D was almost not mentioned after this chapter. The reason for this was that C&D poses the least challenge for recycling much like pre-consumer plastic waste needing little
- treatment and processing because of the absence of much less contamination compared to MSW. ELV and WEEE stay in between and are mentioned in later analysis.
Plastics Separation Processes
Plastics separation from mixed wastes, especially, from domestic household waste and/or similar MSW sources could involve up to 3 or more (i.e. mix of preparatory and actual polymer) separation processes before the final plastic recyclates are ready for reuse, reprocessing or conversion. The first separation process would be to separate the dry recyclables such as plastics, metal, glass and paper from the organic-rich fraction of the incoming waste. The resultant dry co-mingled rigid recyclables can then be further sorted into it different component streams using any or combination of automatic and manual sortation methods/techniques.
In the second separation process, automated pre-sorting (usually based on magnetic, density and spectrophotometric properties) can sufficiently separate plastics stream from metals, glass and paper (excluding labels and closures on plastics). The third separation process would involve the separation of the plastics stream into it various different components, usually, PET, HDPE, LDPE, PP and PS present in the mixed household waste originally. Manual hand sorting is considered the fourth separation process with significant potential impact on product purity, which tends to be greater than 95% in most cases.
Manual hand sorting downstream the overall separation process is commonly considered by trained and experienced operators as a good practice and as an integral part of the sorting system (WRAP, 2010). Manual sortation is not an uncommon upstream process in MBT or/and dirty MRF plants as well, often operated through polarized light from Ultraviolet (UV) ray for the separation of PVC from PET. Further separation processes could be deployed when rework is necessary and/or when there is need to improve the quality level of the final plastics recyclates to near virgin plastics quality.
PET OR PETE
Bottel water, contiments, Safe for Single Use, should not be reused or heated.
Milk jugs,yogurt cups, juice bottls. Not known to leach toxic chemiclas. safe to reuse.
Bibs, inflatables toys, mattress covers, cling wrap. Releases dioxin, may contain phthalates & lead.
Sopt, flixible food bags(bread, fronze foods, resealable bags), squeezable bottls. Safe to reuse.
sippy cups, baby bottles, kitchenware, toys. Safe to reuse. Do not microwave.
Disposable utensils & food containers Styrofroam. Can leach styrene (a neurotoxin).