10 Aug, 2020 12:45 AM / by Quek Leng Chuang
Why not incinerate? – The Case for Pyrolysis
The waste incineration system in Singapore is sophisticated. Why do we propose plastic pyrolysis and turn Plastic waste to NewOil instead? We believe it is a far better local solution to tackle the plastic waste issue we have in Singapore.
1.Creating more sustainable diesel
When we process plastic with our Plastic-to-NewOil process, we further refine NewOil into diesel fuel which can be used in a versatile way for cars, trucks and diesel engines in the manufacturing sector. But waste incineration creates electricity as well, right? In our opinion, it is more valuable to create diesel fuel instead of electricity as otherwise, diesel must be sourced from fossil fuels, putting additional strains on the natural environment. We can source electric energy in other, more sustainable ways from renewable energies such as photovoltaic and solar panels on spare roofs of buildings. This way, we can harvest clean energy which does not create residues and flue gas as an incineration process does.
2. Diverting waste away from the landfill
When conducting Plastic to NewOil pyrolysis, we are left with carbon black as the only residue from the process. Carbon black is not waste and can be reused as a source of energy again so plastic-to-fuel pyrolysis is virtually a zero waste method to treat plastic waste!
Currently relying on incineration, waste is not truly recycled or converted to energy but only condensed to lower the overall volume by 90% in Singapore. We are still left with incineration ash that must be disposed of into the landfill thereafter. As the space there runs out quickly, depleting our possibilities to handle waste, pyrolysis is a suitable option to divert considerable amounts of waste away from the landfill. The recycling rate for plastic waste in Singapore (4%) is particularly low, so we see a great potential to divert more plastic packaging waste away from the landfill by treating it with pyrolysis.
Why do we not opt for mechanical recycling instead? Plastic packaging waste in Singapore consists of many different kinds of plastic that are often complicated to separate. In order to be recycled and reused for new material, they all need different cleaning, sorting and treatments. Moreover, a high share of this packaging waste is contaminated with liquid or food residues so recycling facilities struggle when processing it. Therefore, we see plastic to NewOil pyrolysis as a sound solution in order to divert plastic packaging waste in Singapore away from landfills and to create additional value from it.
3. No need for extra energy
In order to properly incinerate all kinds of waste, we first need to heat a rotary kiln to more than 980 degrees Celsius. Only this reduces the volume and treats the waste properly in several steps so we can finally dispose it on the landfill. However, we need energy to start the process first.
For plastic pyrolysis, we also need to heat the pyrolysis reactor first. To kickstart the process, we simply use our urban wood waste gasification system. When the reactor shows sufficiently high temperatures, we can start with pyrolysis. We only need temperatures around 400 degrees celsius, so less energy is required to heat and sustain the temperature in comparison with waste incineration. After the process begins, pyrolysis works without further energy from the outside, only fuelled by combustible syngas that we obtain as a byproduct from pyrolysis.
These are definitely some good reasons to conduct Plastic-to-NewOil pyrolysis instead of waste incineration for packaging waste. Do you have packaging waste that we can use to transform it into the first 100% Singapore-made NewOil? Get in touch with us so we can work together for a sustainable transition into the age of renewable energies and circular economy.
Written by Quek Leng Chuang
LengChuang is a chemical engineer and an expert in carbonomics. He is the founder and owner of Environmental Solutions (Asia) Pte Ltd.