Are bioplastics the logical consequence for packaging?
A lot of confusion still exists around the environmental claims made by the manufacturers of degradable plastics. The general perception is that degradable plastics will dissolve and disappear over time versus conventional plastics that will be around forever.
Although bioplastics is a relatively new field within the South African plastics sector, it is driving the evolution of the plastics industry and recognised as representing a crucial pillar of the bioeconomy.
What are bioplastics?
Bioplastics form part of the bio-economy concept, which focuses on sustainable production and conversion of biomass into a broad range of products. Bioplastics are not just one single material but comprise of a whole family of materials with different properties and applications. “Bioplastics” refers to plastics made from plant or other biological materials does not speak to the biodegradability or compostability of the product.
Benefits of bioplastics
Bioplastics save fossil resources by using biomass which regenerates and provides the unique potential of carbon neutrality.
It is important to recognise, however, that manufacturing bioplastics is a complicated and energy-intensive process and that it is still dependent on fossil fuels. Fossil fuels are also used to make fertilisers and pesticides used to increase crop yields.
Will the use of bioplastics solve the problem of littering?
Biodegradable plastics are often regarded as a possible solution to littering as they can be decomposed by micro-organisms without producing harmful residue during decomposition. However, the process of biodegradation is dependent on certain environmental conditions i.e. temperature, presence of micro-organisms, timeframe, etc. Littering should never be promoted for any kind of material or waste.
It is imperative for the consumer to continue to be conscious of the fact that no matter what type of packaging or waste, it must be subject to appropriate disposal and recovery processes.
Can bioplastics be recycled mechanically?
If a separate recycling stream for a certain plastic type exists, the bioplastic material can simply be recycled together with their conventional counterpart, for example bio-PET bottles can be recycled with PET bottles. However, there is no separate stream for the recycling of post-consumer biodegradable or compostable plastics materials. SA has no commercial composting facilities for compostable plastics as yet.
Things to consider before introducing biodegradable products:
1. Products with any of the following compost ability standard specifications are certified for industrial composting only: ASTM D6400, ASTM D6868, EN 13432 or ISO 17088. Such materials have been tested and certified to degrade under specific conditions at a temperature of around 60 °C. These certifications do not cover home composting or environmental degradation at ambient temperature. Furthermore, the degradation rate of these materials has been shown to be significantly slower in an aquatic environment than in soil.
2. South Africa currently has very few large-scale industrial composting facilities that are managed to maintain the conditions required by the above certifications.
3. There are currently no large-scale post-consumer waste management programmes for the separation and processing of biodegradable and compostable packaging. As a consequence, these materials have no intrinsic value to formal or informal waste collectors, so the products are likely to remain in the environment or at best, end up at landfill.
4. There is currently uncertainty about the impact that these materials will have on the efficient operation of existing recycling operations and the integrity of recycled products should biodegradable / compostable products be incorporated into recyclate. Biodegradable and compostable materials will be contaminant to the recycling waste stream.
The way forward
Whilst it agrees that there are certain uses and applications that could potentially be ideally suited to degradable plastics, Plastics SA warns that introducing bioplastics to the country’s burgeoning and well-developed recycling industry would contaminate the recycling streams. This could potentially have disastrous and costly consequences on the plastics recycling industry has in recent years become an integral part of South Africa’s economy.
Last year alone, 519 370 tons of plastics waste were collected for recycling and provided employment to almost 60 000 people. R2.3 billion rand was injected into the informal sector through the purchasing of recyclable plastics waste which was used to make many new long-term plastic products for example, agricultural- and building products such as water pipes, builder’s film, fencing and decking, as well as carpeting, geo-textiles, strapping and plastic timber.
For more information, visit www.plasticsinfo.co.za