By Matthew Stone
When the by-products of agriculture, industry and day-to-day life arrive at a waste-processing facility, they haven’t necessarily reached the end of their useful life. A new technology is now being showcased that can convert biogas into a high-grade liquid fuel as a direct replacement for fossil fuels.
It’s no secret that waste is a mounting problem around the world. According to a World Bank study, cities will create approximately six million tonnes of solid waste per day in 2025. This would be enough to fill a line of rubbish trucks totalling 5,000km long, every day.
Currently, this waste is handled in several ways, including incineration, landfill disposal, recycling and even energy conversion. It’s these latter two methods of processing that are considered the most environmentally friendly and sustainable, allowing used products to be repurposed to reduce the amount of waste that is buried. This is particularly important given the focus that European countries have placed on reducing waste pollution, especially plastics.
The European Union’s focus on reducing plastic waste has brought waste-to-energy technology into the limelight in the past year. In early 2018, a proposal to include fuel derived from fossil-fuel waste materials such as discarded plastic in the EU’s Renewable Energy Directive gained momentum among several member states. This faced criticism from several environmental non-government organisations (NGOs), notably Zero Waste Europe.
However, the concept behind this idea is still effective if it is applied to waste materials that are not derived from fossil fuels. A prime example is food waste, which a recent report from the Boston Consulting Group anticipates will total 2.1 billion tonnes annually in 2030. This will be the equivalent of US$1.5tr wasted every year.
By applying the same waste-to-fuel approach to food waste, countries and businesses alike can reclaim this otherwise lost value. The process for biodegradable waste often involves anaerobic digestion, in which it is broken down into biogas that can be converted into a liquid fuel using a Fischer-Tropsch (F-T) process.
Unfortunately, the process of producing biofuels with an F-T process is very energy-intensive, so it has to be done on a large scale, with external input, to make it a viable option. This has significantly affected the uptake of investment in biofuel technology.
However, this is now changing. Renovare Fuels has developed a new technology to efficiently turn biogas into a high-grade liquid fuel that can be used as a direct replacement for fossil fuels. Developed at the University of South Florida in conjunction with Nasa and the US Department of Energy, the technology previously proved successful in converting biogas into usable diesel during a trial at a US landfill site in 2017.
The technology uses a specially developed F-T catalyst and advanced engineering techniques to overcome the barriers that have traditionally held the process back. This results in a carbon-neutral method of efficiently producing a drop-in fuel that is physically and chemically similar to traditional petrol, diesel and jet fuel.
In addition, the process itself is entirely self-sufficient, with the water and gas produced being reused to power the system itself. This means no external energy input is required and the process remains carbon-neutral.
Crucially, this means that businesses can reap financial benefits from the waste they produce. This is particularly useful for agricultural businesses and wastewater utility operators, where the biodegradable by-products of other operations can be converted to, and used on site as, a source of energy for future processes. Because the biofuel is middle distillate and virtually identical to traditional fossil fuels, engines do not need modifying and the new fuel can directly replace existing fuels, or be blended as required.
On a wider scale, this means that Renovare’s fuel can directly offset the usage of fossil fuels for petrol, diesel and jet fuels. Based on a 2016 report from Defra, the UK produces 31.8 million tonnes of biodegradable waste every year. From this, Renovare estimates that its technology can displace more than two billion litres of fossil fuel annually.
With this breakthrough in waste-to-fuel technology, it’s apparent that landfills are not the end of the line for biodegradable waste. With the right technology and systems in place, countries and businesses can combat the global waste problem and offset fossil fuel reliance in an efficient, effective way.
Matthew Stone is chairman of Renovare Fuels. For details of on-site demonstration invitations to see the company’s technology in action, email [email protected]