Understanding Pet Plastic Volume: Standard Quantities Explained

Polyethylene terephthalate, or PET, is a common thermoplastic polymer resin of the polyester family. It is used in fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing. In 2016, the annual production of PET was 56 million tons, with bottle production accounting for about 30% of global demand. PET bottles are widely recycled, with countries like Switzerland recycling about 75% of them. The prime uses for recycled PET are polyester fibre, strapping, and non-food containers. Researchers are also working on methods to upcycle PET into performance-advantaged nylon, which can be used to create a range of new products, including waterproof clothing, stick-free cookware coatings, and heat-resistant machine parts.

PET bottle weight

Polyethylene terephthalate (PET) is the most common thermoplastic polymer resin of the polyester family. It is used in fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing. The biggest application of PET is in fibres (over 60%), with bottle production accounting for about 30% of global demand. In 2016, the annual production of PET was 56 million tons, with 485 billion PET bottles produced globally. It is forecasted that this number will increase to 583.3 billion in 2021.

The weight of a PET bottle depends on its volume. For instance, the average weight of a standard 1.5-litre PET carbonated drink bottle is approximately 32.6 grams. A larger 2-litre capacity soda bottle (without a cap) made of PET weighs about 53.61 grams. Fourteen monoliths 3D-printed using PET were weighed, and the average weight was found to be 35.8 ± 0.5 grams.

The recyclability of PET is more practical than many other plastic applications due to the high value of the resin and its almost exclusive use in widely-consumed water and carbonated soft drink bottling. PET bottles are recycled to a substantial degree in many countries, with about 75% recycled in Switzerland. The recycled material, known as rPET, r-PET, or post-consumer PET, is used for polyester fibre, strapping, and non-food containers.

The health risks associated with PET bottles have also been a subject of study. The Swiss Federal Office of Public Health found that small amounts of antimony migrate from PET into bottled water, but the resulting low concentrations pose a negligible health risk. However, reusing plastic water bottles can increase the risk of the inner surface deteriorating and releasing more phthalates, which raises concerns about drinking water stored in plastic bottles.

PET bottle production

Polyethylene terephthalate (PET) is a thermoplastic polymer resin of the polyester family. It is the most common type of plastic resin and is used in the production of fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing. PET is particularly popular for producing any type of bottle that comes into contact with food or potable water. This is because PET is lightweight, strong, durable, and recyclable.

The process of manufacturing PET bottles begins with polymerization, which creates long molecular chains of plastic. This process can be complex and may result in inconsistencies between batches of PET. Once the PET is polymerized, it is heated and placed in a tube-shaped mould called a parison, which is then cut to the correct length after cooling. This creates a bottle preform, which includes the characteristic screw top. The preform is then cooled and may need to be reheated before blow moulding.

During blow moulding, the preform is placed in a two-part mould that closes around it. The inside of this mould is shaped like the finished bottle. A long needle stretches the preform upward, which will become the bottom of the bottle, while simultaneously blasting pressurised air into the preform to force it against the sides of the mould. This process must happen quickly to maintain the bottle's integrity and consistent shape. Some manufacturers weld a separate bottom piece to the bottle during blow moulding, while others create the bottom from the preform along with the rest of the bottle.

The final step is cooling the bottle, which must be done almost instantly to prevent it from losing its shape. Manufacturers may cool the bottle by circulating cold water or liquid nitrogen through the mould, or by filling it with air at room temperature. After the bottle is cooled, it undergoes testing to guarantee that it is safe for use.

The annual production of PET bottles is substantial, with 485 billion bottles produced in 2016 and a forecasted production of 583.3 billion bottles in 2021. PET bottle recycling is also significant, with a high recycling rate compared to other plastics. For example, about 75% of PET bottles are recycled in Switzerland. The recycled PET is used for polyester fibre, strapping, and non-food containers.

PET recycling

Polyethylene terephthalate (PET) is a thermoplastic polymer resin of the polyester family. It is used in fibres for clothing, containers for liquids and foods, thermoforming for manufacturing, and in combination with glass fibre for engineering resins. In 2016, the annual production of PET was 56 million tons, with bottle production accounting for about 30% of global demand.

PET is highly recyclable, yet only 28% of PET bottles are recycled. PET bottle recycling is more practical than many other plastic applications because of the high value of the resin and the almost exclusive use of PET for widely used water and carbonated soft drink bottling. PET bottles lend themselves well to recycling. In many countries, PET bottles are recycled to a substantial degree, for example, about 75% in Switzerland. The prime uses for recycled PET are polyester fibre, strapping, and non-food containers.

The PET recycling process involves consumers sorting PET bottles and then sending them to a recycling plant along with other recyclable materials. At the recycling plant, the various recyclable materials are separated, with glass and metal moving into their own recycling streams. Once all the non-plastic waste has been removed, high-value recyclable plastics like PET are separated using automatic systems or sometimes by hand. The PET is then compressed for ease of transport and sent to a processing centre. The bottles are then ground into small flakes and washed to remove contaminants such as glue, ground-up lids, rings, and labels. After the washing process, the PET flakes are converted into a high-temperature decontamination section where migrated post-consumer substances and flavours are removed. The cleaned PET flakes are then converted into spherical, crystalline PET pellets for the production of new PET bottles. These recycled PET pellets are then sent to manufacturers for use in the packaging industry.

There are also advanced recycling methods for PET, such as chemical or mechanical recycling, which involve breaking down the plastic into its monomers through processes like glycolysis, methanolysis, or hydrolysis. These monomers can then be used as building blocks for new materials, including other types of plastic. Additionally, researchers are working on engineering microorganisms to break down PET and upcycle it into performance-advantaged nylon, which can be used for products like waterproof clothing, stick-free cookware coatings, and heat-resistant machine parts.

PET waste

Polyethylene terephthalate (PET) is a type of thermoplastic polymer resin from the polyester family. It is used in the creation of fibres for clothing, liquids containers, food containers, and thermoforming for manufacturing. In 2016, the annual production of PET was 56 million tons, with more than 82 million metric tons produced globally each year to make beverage bottles, packaging, clothing, and carpets. PET is one of the largest sources of plastic waste, accounting for 12% of global solid waste.

PET bottle recycling is an industrial standard process that is offered by a wide variety of engineering companies. The high value of the resin and the almost exclusive use of PET for widely-used water and carbonated soft drink bottling make PET bottles more practical to recycle than many other plastic applications. In many countries, PET bottles are recycled to a substantial degree, for example, about 75% in Switzerland. The recycled PET is used for polyester fibre, strapping, and non-food containers. PET is also gaining market share as a carpet fibre due to its recyclability and the abundance of post-consumer waste in the form of bottles.

There are two main types of PET bottle recycling: chemical and mechanical. Chemical recycling involves breaking down the plastic into its monomers, which can then be used as building blocks for new materials. This process is more energy-intensive and produces more emissions than mechanical recycling. Mechanical recycling involves processing the PET into flakes, which are then washed, dried, and crystallized before being transformed into new products.

To further incentivize the reclamation of PET bottles, researchers from the National Renewable Energy Laboratory (NREL) and Oak Ridge National Laboratory (ORNL) have developed a method to upcycle PET into performance-advantaged nylon, which can be used to create a range of new products such as waterproof clothing, stick-free cookware coatings, and heat-resistant machine parts. This process involves engineering microorganisms to break down the PET into smaller pieces that can be recycled into higher-value plastic materials.

PET volume in packaging

Polyethylene terephthalate (PET) is a widely used polymer resin of the polyester family. It is a versatile material with a range of applications, including in fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing. In the context of packaging, PET is a popular choice due to its durability, transparency, and recyclability.

In the packaging industry, PET is commonly used for beverage bottles, food containers, personal care products, and household products. Its durability and impact resistance make it a good choice for ensuring products stay contained during handling and transportation. Additionally, its transparency allows customers to see the products inside, which is particularly valuable for food and beverage packaging. The chemical inertness of PET also helps maintain the taste of food items, and its lightweight nature makes it a popular replacement for glass bottles.

The production of PET bottles has increased significantly over the years. In 2016, about 485 billion PET bottles were produced globally, and it was forecasted that this number would reach 583.3 billion in 2021. PET bottles account for about 30% of global PET demand, with fibre production being the biggest application, at over 60%. PET is also used in non-fibre applications, such as packaging, which makes up about 6% of world polymer production by mass.

While PET has become a popular packaging material, there have been concerns about its environmental impact as a significant source of plastic waste. However, the recyclability of PET is a positive factor, and it is gaining market share as a carpet fibre due to its recyclability and the abundance of post-consumer waste in the form of bottles. Researchers are also working on methods to upcycle PET into performance-advantaged nylon, which can be used to create a range of valuable products, including waterproof clothing, stick-free cookware coatings, and heat-resistant machine parts.

Frequently asked questions