PETpla.net Insider 10 / 2019

MATERIALS / RECYCLING PET planet Insider Vol. 20 No. 10/19 www.petpla.net 25 Recycling rates for aluminium cans vary worldwide. In the UK, the recycling rate has reportedly risen to 75%, its highest ever level. In the US, a 2017 report showed the consumer recycling rate had seen a decline, to 49.4%. In Brazil, it’s more than 90%. In some countries rates are increased by income disparity, as the value of aluminium creates an economic impe- tus for collection. Durability and flexibility When it comes to durability, plas- tic bottles have an inherent advan- tage. While dented cans often end up on retailers’ discount shelves, plastic is less likely to deform in transit. Flexibility is another advan- tage for PET. While supermarket shelves are stacked with resealable bottles of water in convenient differ- ent sizes, a 2 l can of water is much less practical. Shelf life Shelf life is often defined more by contents than packaging, but it is a consideration. Drinks in cans gener- ally have a longer shelf life than those in PET bottles. Additives can improve the barrier properties of PET to extend shelf life, but there is often an environ- mental impact. Some are introduced in small enough quantities that recy- clability is not affected. Others, such as colourants, mean the bottle cannot be recycled for food grade applica- tions. The food grade factor Not all PET can be recycled back into new water bottles. Contamina- tion, polymer degradation and addi- tives can all affect suitability for food grade applications. New technologies could help to resolve this. Chemical recycling shows promise as a way to upgrade lower-quality PET back into virgin-grade resin. This is a mid-term trend in the experts’ view, with signifi- cant volumes of chemically recycled material at least 5-10 years away. So, while 3 million tonnes of PET bottles will be mechanically recycled back into food and beverage bottles by 2029, the total will climb to 4.6 million tonnes with chemical recycling vol- umes. In the case of aluminium, the recycling process itself has a sanitis- ing effect. Cost of materials Aluminium is currently around US$ 1,750-1,800 / tonne. A 330ml can weigh around 16 g. The polyester for PET is around US$ 1,000-1,200/ tonne. A PET water bottle weighs about 8-10 g for 500ml. However, as carbonated drinks need a stronger bottle the average weight will be around 22-25 g for 500ml. Plastic material does cost less and go further. On a per-litre basis a beverage will cost less to distribute, with less energy needed to transport it. If the product is water, rather than a higher value beverage such as beer, the cost impact is amplified. Additional costs are typically pushed along the value chain to the customer. Price sensitive consumers may not tolerate the increase, so brand owners may be forced to absorb the additional cost. Availability of stock In the UK alone, 7.7 billion plastic water bottles are used each year. Wood- Mac estimate that replacing that with 7.7 billion cans would require 99,000t of additional aluminium sheet stock. For some years, the aluminium rolling industry has been switching away from producing can stock to more profitable sheet for automotive applications. To trigger a reversal of that investment the conversion margin would need to shift. Rolling mills would have to be incentivised by a significant increase in the price of can stock. Such a radical shift wouldn’t happen overnight. But regulation could drive a step change in polymer demand, with an impact on invest- ment cycles as a result. So, will aluminium cans replace plastic bottles? Brands offering cans of water could find a receptive market, and it will be interesting to see how consumers respond over time. How- ever, Wood Mackenzie’s data shows a trend decline in the consumption of aluminium beverage packaging over the next ten years, except for a few emerging markets in Southeast Asia. Meanwhile, PET bottle consump- tion is increasing, at a global level and in most regionals. Healthy living is one important driver. Put simply, people are choosing a bottle of water over a can of fizzy drink. And the industry is changing. Targets are being set across the value chain to improve col- lection and recyclability and maintain more of a closed loop. Is there a better alternative to PET? The analysts’ finding is that there’s no easy answer. Each material brings its own challenges. Paper or card options typically have a polymer coat- ing that can be challenging to recy- cle. Glass is heavy, and inefficient to transport. Bioplastics have been criticised for diverting arable land from food crops, amongst other potential trade-offs to the environment. And will consumers pay for greener, but cost- lier alternatives for water on the go? www.woodmac.com Chemical recyling growth forecast