Microwave technology set to boost on-farm biogas production

A microwave system has recently been designed to treat organic by-products, such as slurries, within a biogas production process.

Ashleigh Environmental – an Irish CleanTech company based in Co. Waterford – has been developing its proprietary microwave treatment system called ‘Biowave‘ for the past eight years and recently completed its industrial-scale pilot plant.

The system works by transferring electromagnetic waves into the feedstock, thereby creating a disruption of the material’s cell wall.

This enables a more efficient breakdown process and a greater overall biogas production rate.The system also reduces biogas production time and, as a result, a smaller anaerobic digester can become a more feasible option.

A fully-developed control and automation system is also a key aspect of the overall offering. As a result of this, operator time is significantly reduced.

Trial results

Trials have also shown a marked increase in biogas production from pig slurry – the first trial feedstock – and the company is now working on process improvements and is expanding its technology into other waste treatment processes.

As a cell disruption technology, microwaves are especially useful due to superior heat transfer efficiency compared to conventional heating.

Commenting on the project, Ken McGrath, the co-founder and managing director of Ashleigh Environmental said: “We’re delighted to have developed an industrial-scale system that enhances the production of total biogas from on-farm organic wastes; while also reducing the process time to generate renewable gas.”

We come from a farming background and to be able to demonstrate biotechnology that can be integrated with the farm and contribute towards sustainability within agriculture is very important for us.

“We see huge potential for the technology, firstly within the anaerobic digestion market since various organic waste streams can theoretically be treated, but also within the larger bio-economy.

“Its modular design means integration to new or existing plants is very realistic,” he said.

The technology was recently shortlisted for Best Process Optimisation in anaerobic digestion and Best International Agricultural Plant at the upcoming AD and Biogas Industry Awards in Birmingham.