Industrial Waste and Co-products
Many industrial processes and manufacturing operations produce residues, waste or co-products that can potentially be used or converted to biomass fuel. These can be divided into woody materials and non-woody materials.
Woody Wastes and Residues
Technically, the basic technologies available to make use of woody wastes and residues are the same as those available for virgin wood.
Wood waste can be utilised by a range of thermal conversion technologies. It can be burned in combustion systems such as a boiler for the generation of heat for space heating or process heat, or used for electricity generation in a dedicated system or combined heat and power (CHP) co-generation system.
Alternatively it can be gasified or pyrolysed:
Although conversion technologies may be technically suitable for use with woody wastes and residues as feedstock there are regulatory and environmental constraints associated with the use of material designated as waste.
These apply to any material that may incorporate contaminants as a result of deliberate treatments, finishes or manufacturing processes, or accidental spills of chemicals or other contaminants. These place them under the jurisdiction of the Waste Incineration Directive (WID) and/or Pollution Prevention and Control (PPC).
Heavy metals, arsenic and halogens in particular, if present in treatments or contaminants, are likely to cause hazardous or toxic content of bottom ash, fly ash or flue gas emissions. If so, this is likely to require suitable filters or traps on the flue, suitable handling and disposal of ash and adsorbant, and possibly monitoring of emissions.
Types of Woody Wastes and Residues
A number of industries also generate wastes, co-products or residues that are not primarily woody in nature, but are still biomass derived and are also potentially suitable for use as biomass fuel.