What do sunlight, petrol, natural gas and plastic waste have in common? They are all sources of energy.
It is important to understand where plastic comes from.
Plastics are made from refined crude oil, which means that, technically, energy can be derived through the simple burning of plastic. However, that leads to unwanted emissions, which is bad for the environment.
Nevertheless, by employing technologies such as pyrolysis-gasification and pyrolysis-reforming, we can derive the "energy" from plastic without the release of harmful emissions. These technologies lead to the formation of liquid and gaseous fuels, which are quite efficient. These can be further refined and even used as transport fuels.
Recycling is a good alternative but, unfortunately, it is not being practised as well as it could be.
Energy generation, on the other hand, has added incentives. When plastic is converted to fuel, the amount of plastic waste is reduced and energy is generated in the form of fuels, syngas or hydrogen, which can be used for various purposes. Even non-recyclable plastics can be used for energy generation.
Singapore is promoting the use of renewable energy, such as solar energy, and plans to install solar panels in 5,500 public housing blocks by 2020 (HDB crosses halfway point in solar target, Nov 2, 2017). However, more effort needs to go into tackling plastic pollution.
Waste-to-energy technologies are still on a pilot scale and need further research.
I urge the Ministry of the Environment and Water Resources to take serious and decisive steps in managing the plastic waste problem by taking steps such as:
• enforcing legislation such as taxes discouraging plastic use;
• stopping shops and malls from providing free plastic bags; and
• implementing regulations on the sorting of plastics to encourage recycling and energy generation.
While it is not possible to completely phase out plastics, research and development in the generation of energy from plastic waste can be encouraged, tackling two problems at the same time - energy generation and plastic waste management.
Snigdha Sharma (Dr)