CleanHub's Plastic Waste Glossary


Co-processing is a single industrial process, which involves simultaneous mineral material recycling and energy recovery, for example, cement manufacturing through the incineration of waste. 

CO2 emissions

The release of carbon dioxide due to natural or human sources. The natural sources of CO2 release include decomposition, respiration, and ocean release. The main human source, which is the major reason behind the ever-increasing CO2 in the atmosphere in the current era, is the burning of fossil fuels, such as coal and oil.

In 2019, plastics generated 1.8 billion tonnes of greenhouse gas emissions – 3.4% of global emissions – with 90% coming from their production from fossil fuels.


Providing false or misleading information to the public, investors, and other stakeholders by an organization about the environmental impact of its products, services, and operations. The major form of greenwashing is providing incomplete information and exaggerating it to trick people. Common examples include mentioning recycled materials without providing the exact percentage or claiming energy-saving benefits without going into detail.


A landfill is a type of waste disposal in which the solid waste is buried and placed on top of each other inside a large facility well-engineered to ensure the pollutants (scientifically termed as leachate – a liquid material leaked from the waste) don’t enter the ground and contaminate the soil and the groundwater. Regardless of the intense safeguards, there are numerous environmental issues associated with landfills, with the main ones being toxins, greenhouse gases, and leachate.  

Ocean plastic

Ocean plastic is the plastic present in the oceans. It includes both macro and microplastics. It usually enters through numerous land and ocean-based sources, such as rivers and drains, the waste dumped in the oceans, and beach pollution.
An estimated 11-14 million tonnes of plastic enter our oceans every year. And those numbers are expected to triple by 2040. Nobody knows for sure, how much plastic waste has accumulated in our oceans and the deep sea to date. But scientists have estimated the shocking number of about 150 million tonnes.
The most commonly found waste items in our oceans are cigarette butts, food wrappers, beverage bottles, straws, cups and plates, bottle caps, and single-use plastic bags.

Ocean-bound plastic

Ocean-bound plastic is the plastic that is headed towards or at risk of entering the oceans. This generally involves the plastic present in the rivers, plastic dumped on the beaches, and the plastic waste generated by companies and communities along the coastline (within the range of 50 km) with inefficient or non-existent waste management. 


A polymeric material that can be molded or shaped into almost anything when put under heat or pressure. This plasticity, coupled with transparency, toughness, and low electrical conductivity and density, make it an excellent material to make a plethora of products. 

There are several types of plastics that all need to be treated differently for recovery:

1. Polyethylene terephthalate (PET or PETE or polyester)

Polyethylene terephthalate or PET is the chemical name of polyester, a word that you might have seen on various clothing tags. It is a strong, stiff, and lightweight material. In clothing, polyester is commonly blended with other fibers, such as rayon, wool, and cotton, to make them resistant to wrinkles. It is also used for insulation in clothing, furniture, and pillows. Other common uses include carbonated-beverage bottles, water bottles, and jars for food processed at low temperatures. PET has a very high recycling potential, and research suggests that its bottles can be recycled and reused at least 10 times. PET is recycled in two ways. It is either thoroughly cleaned and re-melted to make new items, or it is chemically broken down to make new resin. In the EU, the recycling rate of PET stands at around 50%.

2. Polyvinyl chloride (PVC or Vinyl)

Many of you would have heard the word vinyl while purchasing products such as flooring or wall covering. Well, it’s short for polyvinyl chloride, a high-strength thermoplastic material. It has a wide range of uses in multiple industries, such as building and construction, health care, electronics, and even automobiles. Common products include pipes, wire and cable insulation,  windshield system components, and blood bags. PVC can be recycled up to 8 times depending on the type of material, but sustainable recycling of all types is not possible. In addition to this, PVC can’t be recycled alongside or into other plastic types. The recycling process involves breaking PVC into pellets and then melting it to create other vinyl products. 

3. Polyethylene (PE)

Polyethylene or polythene is a very common plastic type that is available in numerous crystalline structures. Let’s look at each of them in detail:

3.1 Low-density polyethylene (LDPE)

Low-density polyethylene or LDPE, also commonly referred to as plastic number 4, is soft, flexible, and lightweight. It is generally used for making manufacturing containers, orthotics, prosthetics, wash bottles, grocery bags, injection molded parts, and flexible packaging material. LDPE is recyclable plastic, but it can only be recycled once because the recycling process degrades the quality. It involves melting the plastic, removing contaminants, and turning it into thin plastic sheets.  

3.2 Medium-density polyethylene (MDPE)

Medium-density polyethylene or MDPE is stiff and tough making it an excellent choice for tubes, ice boxes, toys, gas pipes, over-wrap films, milk pouches, and lamination films. MDPE comes under plastic number 2 and is recyclable. 

3.3 High-density polyethylene (HDPE)

High-density polyethylene or HDPE has high impact resistance, high melting point, and high strength. It is type 2 plastic and is commonly used for making chemical tanks, plastic furniture, cutting boards, light-duty tanks, and bin linings. HDPE is recyclable but it can’t be recycled alongside other types of plastic. The process involves plastic sorting, shredding, melting, and cooling into pellets. These pellets are then converted into other products. 

3.4 Ultra-high molecular weight polyethylene (UHMWPE)

Ultra-high molecular weight polyethylene or UHMWPE is similar to HDPE with added high alkali, acid, and numerous organic solvent resistance. Initially, it was tough to recycle UHMWPE but now it’s chemically recycled into crude-free industrial feedstocks, which can be used in cleaning agents, degreasers, paints, etc. The process involves thermal cracking, and impurities removal through hydro-refining, distillation, separation, and blending. 

4. Polycarbonate (PC)

Polycarbonate or PC is known for its good electrical properties, high impact strength, and high dimensional stability. It is an engineering plastic and is generally used for making electrical components, safety helmets, compact discs, bullet-proof glass, car headlamp lenses, and roofing and glazing. PC is fully recyclable, but it needs to be reacted with numerous reactants to convert it into other forms of plastic, as direct interaction with water releases BPAs, which are environmentally harmful. PC can be recycled mechanically or chemically. Mechanical recycling involves, sorting, removing impurities, and shredding the waste into small fragments, which are then used to make new products. Chemically recycling is done by reacting PC waste with phenol in presence of a catalyst to turn into BPA and DPC monomers, which are then converted into plastic. 

5. Polypropylene (PP)

Polypropylene or polypropene is a tough and rigid plastic, highly resistant to numerous chemical solvents, bases, and acids. It is commonly used for making consumer products’ packaging, industrial plastic parts, textiles, and devices like living hinges. Even though PP is highly recyclable, curbside recycling doesn’t support it. The recycling process involves the collection, sorting and cleaning, shredding, separation, and compounding. It can be recycled into clothing and industrial fibers, storage racks and bins, speed bumps, containers, and coffee bags. 

6. Polystyrene (PS or Styrofoam)

Polystyrene, PS, or styrofoam is available in both rigid solid material form and as foam. It is used for making a wide variety of products ranging from refrigerators, ovens, and microwaves to packaging materials due to its inertness. Polystyrene is difficult to recycle and can only be done in a centralized facility. In addition to this, after recycling, PS can’t be used for packaging food because of health concerns. Currently, its recycling rate stands at 12%.

Plastic Credit

Plastic credit is an auditable unit to measure the amount of plastic reduced either through collection from the environment or via recycling into a new item or packaging. The whole process comprises two parties: the companies involved in using plastic in their products or packaging and the organization working towards collecting plastic from the environment or recycling it. They both work together to remove a decided amount of plastic from the environment, which is generally equal to the amount used in business activities. 

Plastic Footprint

A plastic footprint is a measure of how much plastic waste a company, household, or individual generates. It includes the amount of plastic used and produced by you.  

Plastic Neutral

A brand is Plastic neutral when they recover the same amount of plastic from the environment that they use as a business. The most common way to achieve plastic neutrality is to buy plastic credits.  

Plastic Neutral+

A brand is Plastic neutral+ is when they recover more plastic from the environment that they use as a business.   

Plastic Offsetting

Plastic offsetting is a way for companies to compensate for their plastic use by purchasing plastic credits that reduce the amount of plastic that reaches the environment. It is done by calculating the plastic footprint of the brand and then compensating for all the plastic that they use in products and packaging. 

Plastic Treaty

The plastic treaty is a legally binding treaty signed by the UN Member States in March 2022 to end global plastic waste and pollution. The main objective is centered around the whole plastic lifecycle, starting from production to waste management, to encourage and develop opportunities to reduce plastic waste and make the industry circular.


The word pyrolysis is a combination of two Greek words, ‘pyro’ meaning fire and ‘lysis’ meaning separating. It pretty much means the same as well. It’s a process in which very high temperature (typically over 430 °C or 800 °F) is introduced to the organic matter in the absence of oxygen, which causes it to irreversibly change physically and chemically. The goal of Pyrolysis is to obtain a secondary raw material, pyrolysis oil, from plastic waste.


Recycling is the process of turning waste into new products, which would otherwise be landfilled or handled via other harmful waste management processes. There are three main types of recycling:

  • Mechanical Recycling: Mechanical recycling is a type of recycling in which the waste products are turned into new products through mechanical means without changing their chemical composition. Examples include turning plastic waste into new plastic items such as garbage bags. 

  • Energy Recycling: This process involves turning products into thermal or electrical energy through incineration.

  • Chemical Recycling: As the name suggests, chemical recycling involves changing the chemical composition of the waste being recycled. The produced raw materials are then used in different industries to manufacture new products. 

Sustainable Packaging

Sustainable packaging is a type of material that ​​is used to wrap, store and protect products. It supports sustainable development by reducing environmental impact and ecological footprint. It is usually made from recyclable or compostable materials such as recyclable and biodegradable plastics, recycled cardboard and paper, cornstarch, or cellulose which can either be broken down and reused for other products or into compost. One should be aware of the fact that an increasing amount of products are labeled biodegradable or compostable. But in fact, only a minority of them are actually home-compostable. The label 'compostable' most often means 'industrially compostable', so the material will break down only inside the right industrial equipment.

Waste Management

Waste management is the process of disposing of, reducing, reusing, recycling, and preventing waste. It starts with waste generation and ends at the final disposal. The most common forms of waste management include:

  • Landfills: Burying and placing the waste on top of each other in a large facility

  • Incineration: Burning waste at high temperatures that vary based on the type of waste

  • Recovery: Recovering useful materials and resources from discarded items and converting them into an energy source, such as electricity or heat

  • Recycling: Converting waste into new products 

  • Composting; Turning organic waste into nutrient-rich fertilizers

  • Waste to energy: Turning non-recyclable items into energy, such as electricity or fuel

  • Avoidance: Reducing waste generation 

Different countries around the world utilize varying waste management techniques from the ones discussed above. Unfortunately, it is a secondary concern in developing countries, due to which recovery, recycling, composting, and waste to energy isn’t utilized widely in them. If we look at the stats, around 90% of the waste in developing countries ends up in unregulated dumps or is openly burnt.

Waste to Energy

Waste to energy is a technology or a treatment process of converting or recovering energy from a waste source in the form of heat, electricity, or transport fuels as a substitute for e.g. coal.

Are there any terms that you think should be added to our glossary? Let us know!