Sustainable Aviation Fuel (SAF) from Wastewater Sources

Following the recent approval of the SAF mandate by the House of Lords, it was great to read this article about the development of a new route for producing SAF.

In work conducted at Argonne National Laboratory, researchers have developed a method that combines membrane separation and methane-arrested anaerobic digestion to produce large volumes of butyric acid from the wastewater of breweries and dairy farms. This butyric acid can then be converted into SAF. The overall method is particularly advantageous because not only does it generate SAF but it also removes organics from the wastewater, which would otherwise require a carbon intensive process during traditional wastewater treatment. The work was published in ACS Sustainable Chemistry & Engineering and includes estimates of the potential economic and environmental benefits. In particular, it shows that is possible to generate the SAF at a reasonable price per gallon and that the overall product has a 71% reduction in greenhouse gas emissions relative to fossil-counterparts. 

As mentioned by my colleague Giles in his recent report on the debate within the House of Lords, there have been concerns raised about the costs of SAF, and the effect of the SAF mandate on the aviation industry. The development of a new method based on cheap waste sources is therefore a very welcome development and will help SAF on its journey to becoming competitive with traditional fossil fuels. We will therefore watch this space with interest.

In the meantime, we hope that the inventors have protected their intellectual property to help them capitalise on their initial research.