Windhager’s ‘zero emission’ boiler.
The PuroWIN has impressively low emissions compared to other biomass boilers on the market. The patented updraft gasification combustion process results in it being the cleanest biomass wood chip boiler in the world.
Fuel is used to filter the emissions as they are produced: Once the combustion chamber is filled with wood chips, the fuel is ignited, forming an ember bed. The chip above the ember bed carbonises and acts like a charcoal filter. As the wood gas rises it passes through the carbon layer and unburnt woodchip and any fine ash and dust is trapped.
What’s left is virtually pure wood gas, which only ignites in the layer above the unburnt wood chip. This results in emissions that are so low they can hardly be measured.