We often make reference to our pellets’ ENPlusA1 qualities, specifically their low moisture, ash, and dust content, and their high ash melting temperature. What is so important about these qualities?
Low Ash Content
The lower the ash content of your pellet the more productively it will burn, and the more heat your boiler will generate. Higher ash levels will cause your boiler to require more frequent cleaning and maintenance, and could signify greater levels of bark, moisture or other contaminates in your pellets.
NOTE: Although some pellets may appear lighter or darker in colour it is not always the case that darker pellets have a higher bark or ash quantity.
Low Moisture Content
Before heat can be generated from burning a solid fuel it is necessary to drive off any residual moisture content. As wood pellets have been effectively dried throughout the manufacturing process they are a very efficient and highly calorific fuel at the point of use. By comparison, green timber often has up to 60% moisture content, and wood chip fuel is normally between 30 and 45% moisture even as it is loaded into a boiler. Wood pellets are the optimum low moisture, low carbon solid fuel.
The lower the moisture in your wood pellets, the higher the heat output and the more efficiently your boiler will operate. Wood pellets should have a moisture content of 10% or less.
High levels of dust will block your feed system and result in your boiler running with poor efficiency. Our wood pellets go through a dust screening process before being bagged or loaded into delivery vehicles. Our delivery tankers also carry a vacuum system which aspirates dust in the store while the pellets are being delivered. Wood pellets should contain 4% or less of dust at the point of use.
It should be understood that there will always be a certain amount of dust when wood pellets are used as a fuel – since this is effectively what they are comprised of. If wood pellets are manufactured, transported and delivered correctly (in compliance with ENPlus) then the amount of residual dust should not present an operational problem.
High Ash Melting Temperature
A damaging effect to any boiler is what is known as clinker – the incombustible lumps of residue that are left behind after burning. This residue is not only a nuisance to clean out, but can cause damage to the burner pot. Though a small amount of clinker is unavoidable, the impact is limited and the build up significantly reduced with an ash melting temperature above 1200°C, helping to improve the life and efficiency of your boiler.