The proven technology revolutionising anaerobic digestion in the F&B industry

Challenges of existing AD processes

The use of anaerobic digestion (AD) in food and beverage (F&B) production has grown significantly in the last decade. Over the last 12 years, the number of anaerobic digestion plants in the UK has more than tripled, and the technology has significantly reduced carbon emissions, particularly from food waste.

But there are challenges to this growth. In recent months, new anaerobic digestion plants, or expansions of existing ones, have faced opposition from the public and local councils in the UK, with size a common objection.

Current AD plants are large, and take up land that could be used to generate other income. Because of their size, they are fixed and inflexible, meaning F&B companies need to predict and invest in the treatment capacity they’ll need 10-15 years down the line, which is incredibly difficult in today’s uncertain market.

And F&B companies are also coming up against other limitations. Existing AD plants cannot cope with varied inputs, which frequently result in costly plant downtime. And the speed of water treatment, the volumes they can manage, and the amount of biogas produced as a result are all subpar.

In some cases, the economics of using traditional AD to generate energy just don’t add up. For example, when feedstocks have low energy density or AD systems cannot treat feedstock quickly enough.

The current AD process is simply not fit for purpose. The F&B industry needs a viable option that overcomes the core challenges of current systems, helps them navigate future challenges, and provides a significant return on investment.

A new proven technology

In response to these challenges, new electro-methanogenic reactor (EMR) technology has been developed, proven in the field, and is scaling across the UK.

It works by leveraging the power of electro-active microbes, which are all around us but have not yet been put to good use, to simultaneously treat more wastewater and produce more biogas onsite than any other anaerobic digestion system. Specifically, and looking at data from 10,000 operating hours, it drastically improves the AD process for F&B businesses by:

1. boosting energy production by 30%

2. treating waste as much as 10 times faster

3. improving effluent quality by 50%

And it’s not just the performance issues that this technology overcomes. These systems are 70% smaller than existing AD plants, requiring only as much land as a shipping container. They are also modular, which means that F&B companies don’t need to predict and invest in capacity requirements a decade or more in the future. Instead, they can install the capacity they need now and grow their plants as their business and needs expand.

There are significant cost savings too. By providing heat or electricity through high-quality biogas production on site, the technology reduces energy costs and de-risks exposure to gas and other heavy fuels market price fluctuations. The solution also eliminates, or significantly reduces, the need to transport and treat wastewater offsite, significantly lowering wastewater treatment costs and exposure to volatile haulage pricing.

By turning wastewater and by-products into biogas to power production lines, F&B companies can save thousands of pounds on treatment. This means investing in an EMR system directly improves a company’s bottom line, providing return on investment in three-to-five years. EMR solutions also solve the economic problem of low energy dense feedstock, allowing really fast flow rates to increase energy yields, making the process commercially viable for more waste types.

As public and regulatory pressure mounts, and deadlines for SBTi and GHG protocol targets get closer, businesses in the F&B sector are increasingly looking to reduce their environmental impact, as well as costs. The adaptability of EMR technology helps businesses comply with discharge consent limits and other important environmental standards for wastewater treatment, mitigating the risks of hefty fines as a result of improper discharge of wastewater or slurry.

The F&B sector consumes a lot of thermal energy. As of 2023, the industry consumed approximately 1,531 thousand tonnes of oil equivalent (ktoe) of gas in the UK alone. An EMR system decarbonises some of this energy use by generating biogas on site, contributing to a reduction of scope 1-3 carbon emissions within the supply chain.

By recycling wastewater and generating biogas, EMR systems also help protect valuable natural resources and unlock a circular economy. Upgrading wastewater for reuse reduces water consumption and enables F&B businesses to increase sustainable resource management and meet water stewardship targets.

Adopting EMR

The UK market is recognising the potential of EMR technology, with some food and beverage manufacturers already adopting the technology – gaining an edge on competitors and saving over £150,000 a year.

While the science behind the technology sounds complex, these systems are robust and can be operated and maintained (O&M) by the supplier. WASE cover all O&M requirements and use artificial intelligence (AI) to get constant and full visibility on the status of the reactor systems. This is done by combining biosensing and AI to ensure optimal efficiency, to minimise failures and to maximise energy generation – with minimal effort required from customers.

As a result of this approach to O&M, these systems can deliver a ‘hands-off’ operational experience, ensuring F&B businesses can focus on making great produce.

EMR technology can act as a standalone solution but it can also be retro-fitted onto existing, large-scale AD plants to increase performance and capacity, increasing the market opportunity for EMR solutions. It is estimated that there are 756 AD plants in the UK. Maximising the potential and capacity of these sites is an important part of adapting the process to work for the needs of the F&B industry now and in ten or twenty years down the line.

The modular nature of these systems mean they can easily integrate into existing facilities, enabling F&B businesses to unlock further value from feed with two options for integration: a bolt-on digestate and recirculation feed treatment or a direct electrode integration retrofit.

Gaining traction

Pioneer of frozen food, COOK, were looking for ways to reduce their reliance on green gas bought from the grid, improve circularity and lower waste treatment costs. EMR technology provided a solution that could address all three of these objectives.

The business launched a trial of WASE’s technology, setting-up a mini-reactor system to convert leftover pudding waste (such as pie crusts and leftover sauces) into biogas they could use on site. This waste would ordinarily be collected by a haulier and taken to a merchant AD site for further treatment.

The aim of the trial was to demonstrate that the system could handle a small volume of pudding production by-products and convert them into biogas, whilst removing >90% of the COD (organic strength).

During the trial, the organic strength of the pudding by-products were hugely variable (changing depending on what is being baked that day) and this highlighted how resilient the system is at handling fluctuating CODs. Over a period of a week, the system treated by-products with a 10,000-78,000mg/l COD. This variety of organic strength would have a catastrophic impact on the microbiology in a traditional AD system and result in significant intervention and downtime.

The trial successfully demonstrated the effectiveness of EMR technology for COOK, and plans are progressing to install a unit at one of their savoury sites in Kent.

What’s coming next

EMR technology is gaining traction in the UK F&B industry. WASE has multiple operational sites going live across the UK by the end of 2025. And the world’s first Bio-Electrochemical Methane Potential testing laboratory opened at our headquarters in Bristol earlier this year to help F&B businesses understand the full energy value of waste and bio-residues. To meet rising demand, WASE is procuring a second assembly site so it can triple manufacturing production.

But the benefits of EMR don’t stop there. Challenges in green hydrogen production are increasing the focus on biogas as a more viable baseload power solution. With EMR technology, biogas can be efficiently upgraded into biomethane and injected directly onto the grid with the potential to play a significant role in energy security in the near future.