Plastic waste-to-fuel: Understanding the key risks

Detailed scene of a dedicated recycling unit within the plant, focusing on the advanced sorting and cleaning processes used to convert recycled plastic materials into sustainable feedstock.

Converting discarded plastic into fuel is seen as a way to reduce waste. And since the fuel produced can be used to displace fossil energy sources, this conversion can also help lower greenhouse gas (GHG) emissions.

Interest in plastic-to-fuel technology is growing rapidly in the UK, with the Government’s upcoming Energy Bill enabling support of recycled carbon fuels. Several local councils recently granted planning permission for plants.

In the second article of this plastic waste-to-fuel series, we outline the risks of creating fuel from plastic.

Liability risks at plastic processing plants

There are currently two chemical processes for converting plastic waste to an energy carrier — pyrolysis and gasification — and each method carries its own risks.

In pyrolysis, nitrogen gas is used to create an inert atmosphere that is effective in explosion prevention. However, it can cause asphyxiation, particularly in confined spaces, as it depletes oxygen in the environment. Where employees are required to enter an inert atmosphere, a formal management control system in the form of a permit to work should be in place, so that appropriate precautions and control measures can be implemented to mitigate risks.

In gasification, there are potential fire hazards due to the formation of flammable mixtures, both inside and outside the equipment. Air entering a plant could cause a fire inside the premises.

The plastics or feedstock used in both processes are made from differing raw materials, meaning a plant must ensure that none of properties in the waste plastic pose health risks for clients, employees, or the wider population.

Concerns over the environmental risks of plastics processing

The impact of plastic-to-fuel technology on climate change and the environment is top of mind for many stakeholders.

Inefficient gasification or pyrolysis processes can release toxic substances into the atmosphere, soil, and water supplies. Any water used in cooling activities is at risk of contamination. The synthesis gas, also known as syngas, created as a result of gasification contains impurities and pollutants, notably tar. Ash is also produced from the gasification process. Both substances have to be disposed of safely.

Increasing reprocessing rates could lead to an accumulation of contaminants, which require heightened chemical treatment. Eventually, the reprocessing limit will be reached.

The shredding and drying of plastic waste, the pyrolysis and gasification processes, and the decontamination and enrichment of the fuel products require a huge amount of energy. As such, the environmental impact of the process has been questioned.

Process control is vital

Operational risks have to be considered to make the pyrolysis and gasification processes safer and more efficient.

The availability, quality, and composition of feedstock vary widely. Some plastics contain a high amount of corrosive acid that could damage the processing equipment, potentially causing a leak of gases that can be a health hazard or lead to fire, if ignited. In pyrolysis, the different polymers fed into a reactor break along different patterns. Molecules with high degrees of branching crack more easily than linear ones. This makes it more difficult to control the process and stabilise the reactor. Pyrolysis technology is designed to be a steady-state process; variation in the temperature profile across a reactor may lead to hotspots and stress on the vessel shell, and potentially lead to fire or explosion.

A challenge of gasification is tar formation that can lead to a reduction in the overall efficiency of the process. A higher level of tar could render the gas produced unusable.

In both processes, wear and tear due to the high-temperature environment can cause the equipment to fail and downtime. Frequent maintenance and equipment cleaning are required to reduce the risk of blockages and other operational issues, including interruption to the process.

Construction and property risks

Construction risks include design errors, use of improper materials, failure to comply with building codes, supply chain problems, and even negative public opinion as a result of building of the plant. Specialists required to build a plastic-to-fuel plant may not be readily available, prolonging the construction process.

Project leaders could face personal liability as a result of environmental damage caused by the plant, workplace safety violations, or non-fulfilment of contracts. A robust directors and officers (D&O) insurance program can protect the personal assets of the individual directors and officers.

Lastly, a natural catastrophe, such as a flood or earthquake, cybersecurity breach, or fire resulting from an explosion during the plastics conversion process can lead to significant property damage. And these risks could also lead to business interruption and third-party liability.

How to gain optimum insurance terms

It is critical to identify potentially problematic issues during the project’s conception phase, allowing for the development of effective risk mitigation and management strategies. These protocols can then be implemented to cover the lifecycle of the plant and its assets.

Engaging early with a broker or an insurance adviser with experience building insurance programs for similar plants can help in designing a risk transfer programme that fits the project’s specific needs. Project leaders are likely to be asked by the insurer to provide technical information demonstrating that the plant’s technology is proven, key equipment has been sourced from reputable suppliers, and a robust fire strategy is in place. This process is likely to take time, therefore involving a broker early on in the project will help in the negotiation of favourable insurance terms.

Optimum insurance terms require a thorough risk assessment, clear communication of operational processes, a commitment to safety protocols, collaboration with insurers, and the highlighting of risk mitigation strategies in place. A broker or an insurance adviser will tailor a proposal to showcase the specific measures taken to minimise risks, fostering a transparent and trustworthy partnership that will lead to favorable insurance terms.

The final article in the plastic waste-to-fuel series will discuss the key ways to mitigate risks associated with producing fuels from plastics.

3d rendering amount of energy storage systems or battery container units with solar and turbine farm

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Plastic waste-to-fuel: Understanding the key risks

Liability risks at plastic processing plants