The Company’s proprietary CoalSwitch™ and PeatSwitch™ processes have been proven to convert low-value forestry and agricultural waste (feedstock) into high value products.
Both CoalSwitch™ and PeatSwitch™ have significant market potential. An essential difference between AEG’s processes and other biomass beneficiation methods is the pre-treatment and post-treatment processes that effectively removes most of the soluble mineral contaminants thus allowing AEG to source otherwise very low-value, but plentiful feedstock. By leveraging these waste streams, AEG is able to lower its production costs but still produce “top shelf” products that command a substantial premium over other biomass-derived products.
It is a multi-step process involving the following:
- The Pre-Wash Stage – water is added to the feedstock simultaneously removing soluble surface contamination and saturating the feedstock
- The Reactor – the saturated feedstock is transported to the reactor where steam is introduced. While resident in the reactor, the feedstock undergoes a physiochemical process where the fibres are substantially weakened and a portion of the hemicellulose is dissolved through hydrolysis. The removal of the light volatile fraction of the hemicellulose present in all plant fibres is an essential step when producing a true drop-in fuel coal replacement in convention coal power plants.
- Steam Explosion – the reactor is rapidly depressurised resulting in a complete disruption of the fibres in the feedstock. By breaking open the fibres, the remaining interstitial salts and other soluble minerals are exposed so that they can be removed during the post-wash stage.
- The Post-Wash Stage – The now “beneficiated” biomass is removed from the reactor and placed in to a tank with a large volume of water where the remaining soluble mineral contaminants go into solution.
- De-Watering – The mixture of water and beneficiated biomass is then transferred into a mechanical dewatering system where much of the transport water and the beneficiated biomass are separated.
- Drying – The now clean solid product is then conveyed through a fluidized bed dryer to reduce the moisture content to the level specified by the pellet mill manufacturer.
- Pelleting – No additional milling is necessary and the product advances straight to pelleting. Due to the extensive fracturing of the fibre and the operating temperature of the mill, the free lignin is easily activated resulting in a durable and hydrophobic pellet.