Uan Scotland is an innovative company striving to create high quality products which utilise wool as a 21st century super material, harnessing the properties of wool to offer their customers luxury and comfort combined with durable quality. They aspire to provide customers with product traceability, green credentials, "upcycle" solutions and to be supportive to rural Scottish businesses involved within the wool production and manufacturing processes.
As such, they approached the Scottish Biofuel programme to investigate an upcycling solution for the end of life of their product, the project looked at processing the product through Anaerobic Digestion and through Pyrolysis.
Investigation of the potential for energy production via Anaerobic Digestion (AD) was not promising. The keratin rich nature of wool cannot be easily be broken down by the AD process. A pre-treatment is required to change the structure of the wool fibres either by using thermal, chemical or biological means to make the protein readily available to the AD microbes. The additional processing required to run an AD plant using wool as a feed stock is prohibitively high, making it less commercially viable.
Wool supplied by Uan was analysed by the UK Biochar Research Centre testing for the production and profiling of the Biochar, as well as the production of energy rich oils and synthetic gases.
The analysis individually tested the wool from Blue Faced Leicester, Scottish Mule and Scottish Blackface breeds of sheep. Both in the washed and unwashed form. No difference was noticed in the biochar produced from the different sheep breeds. However a difference was found between the washed and unwashed wool samples.
Raw and washed wool show a similar trend of fixed carbon in the biochar with the increase of Pyrolysis temperature, however, the raw samples have a higher ash component. The fixed carbon content of the high temperature biochar has good potential for sequestering carbon in the soil and the higher ash content of the raw wool biochar has the potential for releasing valuable nutrients into the soil.