Introduction:
India is generating about 3.5 million tons of plastic waste annually and the per capita plastic waste generation has almost doubled over the last five years and about 60% of the plastic waste has been recycled annually in India. Plastic is made up of various harmful and toxic chemicals thus it poses a serious environmental threat to modern society. As a result, if not properly managed or processed it will pollute land, air, and water.
Plastic Debris affects at least 267 species worldwide 86% of sea turtles species, 44% of all seabirds, and 43% of marine mammal species. India has been ranked 12th among the countries for mismanagement of plastics. Therefore recycling and reprocessing of Plastic waste has become urgent to overcome this problem and mismanagement. Recycling and reprocessing of Plastic waste involves 5 types of processes based on the quality of the product manufactured upon recycling namely upgrading, recycling (open or closed loop), downgrading, waste-to-energy plants, and dumpsites or landfilling. Usually, the PW is converted into lower-quality products such as pellets or granules, or flakes which are further utilized in the production of various finished products such as boards, pots, mats, and furniture (Centre for Science and Environment (CSE) 2021).
Fig.2 Classification of Plastics
Plastic | Characteristics |
Polyester (EPS) | Lightweight, foamed and energy absorbing plastic |
Low Density Polyethylene (LDPE) | Milky white, soft and flexible plastic |
High Density Polyethylene (HDPE) | Relatively of high grade and used in white |
Polystyrene (PS) | Polystyrene (PS) Stiff but brittle plastic with clear look and glossy |
Plasticized Polyvinyl Chloride (PPVC) | Clear type with flexibility |
Polypropylene (PP) | Hard, but flexible plastic |
Unplasticized Polyvinyl Chloride (UPVC) | Clear type, hard stiff plastic |
Polyethylene Terephthalate (PET) | Hard plastic suitable for fibre production |
Table.1 Variety and characteristics of plastic
From waste to material recovery, PW recycling can broadly be categorized into mechanical recycling, chemical recycling, biological recycling, and energy recovery (Al-Salemet al. 2017). Primary Recycling is most preferable type of recycling because of its contamination-free feature which facilitates a less number of operating units resulting in the optimal amount of consumption of energy supply and resources which is further followed by secondary recycling (mechanical recycling) for recycling PW (CSE 2021). However, processing difficulties and the quality of recyclates are the main drivers for seeking alternative approaches (Ragaert et al. 2017). Comparatively, tertiary recycling or chemical/feedstock recycling is a less favored alternative because of high production and operational costs, as well as the lack of scalable commercial technology in India whereas quaternary recycling which involves energy recovery, energy from waste, or valorization of PW, is least preferred due to uncertainty around propriety and prominence of the technology, and the negative potential to convert land-based pollution to water and air pollution, but anyhow more preferable than dumping into the landfill (Satapathy 2017; CSE 2021). Figure 2 shows the categorization of the recycling process of PW.
Fig.3 Plastic waste flow and recycling categorization (Modified from FICCI 2016; Sikdar et al.
2020; Tong et al. 2020)
2.1 Recycling technologies
Mechanical recycling involves physical processes (or treatments) that convert PW into secondary plastic materials. It is a multi-step process typically involving collection, sorting, and heat treatment with reforming, re-compounding with activities, and extruding operations to produce recycled material that can substitute for virgin polymer (Ragaert et al. 2017; Faraca and Astrup 2019). It�s able to handle single polymer plastic only such as PVC, PET, PP & PS. There are various key approaches to sorting and separating PW for MR, including a zig-zag separator (also known as an air classifier), air tabling, ballistic separator, dry and wet gravity separation (or sink float tank), froth flotation, and electrostatic separation (or triboelectric separation). There are also some newer sensor-based separation technologies available for PW which include plastic color sorting and near-infrared (NIR) (Ministry of Housing & Urban Affairs (MoHUA) 2019). After the collection process, they are melted down directly and molded into new shapes or are re-granulated and these granules are reused in the manufacturing of plastic products.
Chemical recycling, tertiary recycling, or feedstock recycling refers to the transformation of polymers into simple chemical structures (smaller constituent molecules) which can be utilized in a diverse range of industrial applications and/or the production of petrochemicals and plastics
(Bhagat et al. 2016; Jyothsna and Chakradhar 2020). Pyrolysis, hydrogenation, and gasification are some of the chemical recycling processes (Singh and Devi 2019). This type of recycling is used in waste to oil plants (Termed as WtO by CPCB)
Energy recovery is a valuable alternative for the plastics that can�t be sustainably recycled such plastics can�t be recycled in an eco-efficient manner because of few factors are:
Alternate use refers to the use of plastic in some other way and not using the technologies discussed above. One of the best examples of alternate use of plastics is bitumen road making. This process, however, has its limitations in terms of the feedstock-this process can�t take black plastic because of its repeated recycling and less binding properties and PVC can�t be used due to the presence of chlorine which can release dioxin in case of high temperature. More research is needed to understand the long-term effects of plastic being used for alternate purposes in various set-ups to recognize and address questions like leaching, environmental degradation potential, microplastic forming potential and other effects on human health.
Graph 1 Percentage distribution of recycling options
Source: PlastIndia foundation
India is generating about 3.5 million tons of plastic waste annually and the per capita plastic waste generation has almost doubled over the last five years and about 60% of the plastic waste has been recycled annually in India. While the amount of plastic waste that is being recycled in the country matches PlastIndia�s claim of 60 percent; according to 20 to MoHUA, 70 percent of this is recycled in registered or organized facilities which has declined by 97 percent in a year (2018�19), 20 percent is recycled by the unorganized sector which has increased by 60 percent and the remaining 10 percent is recycled at home�which means using the plastic waste for alternate use in a domestic setup.
Many PIBOs and recyclers are completely unaware of the EPR policy. Ecoex contributes to raising awareness by teaching both PIBOs and recyclers about the importance of ethically offsetting their EPR targets. Ecoex believes that every metric tonne of plastic trash in the the environment should be disposed of ethically, and we are working to educate all stakeholders in the value chain.
PIBOs can now fulfill their Plastic EPR obligations directly through Recyclers/End of Life Processors using ECOEX�s digital marketplace. A PCC guarantees that plastic garbage is ethically collected, transported, and disposed of while also ensuring that the monetary benefit is realised by the unprivileged recycling sector. In a plastic credit model, a manufacturer is not obligated to recycle their own packaging but must verify that an equivalent amount of packaging trash has been recovered and recycled to meet their duty. Producers, on the other hand, are required to get proof of recycling or recovery [PLASTIC CREDIT] from appropriately accredited processors [recyclers, W2E plant operators, cement co-processors, users of plastic in the road] or exporters. Producers can exchange credits with processors who have been officially accredited for this purpose, as well as by registering on the EPR portal.
Our main goal with this project was to create awareness of how recycling can help the environment by reducing pollution and greenhouse emissions; which at the same time is affecting the whole world, and how we can make a difference if we start recycling efficiently.
We also wanted to make people aware of how recycling can make an impact in the world by decreasing global warming, decreasing deforestation, and reducing the number of toxic chemicals that go into landfills and pollute the soil and lead to the degradation of land.
The circular economy is a regenerative paradigm that necessitates the involvement of responsible stakeholders. There should be continuous interaction among stakeholders to share current practices dealing with PW as part of the plastic economy. It was found that there was incomplete
and indistinct reporting on PW generation from individual states. Information exchange via technology applications should eventually be an integral part of the PW management value chain. Thus, generation estimation is an essential task to set targets for resource recovery and recycling, which connects the? global commitment. element of the circular plastic economy and waste minimization. Being part of the global commitment to? reducing, circulating, and innovating? under the? the plastic pact,? a national target could be set and a mechanism is developed.