Boiler Ash Options Assessment

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Canfor Pulp Limited Partnership

Canfor Pulp Limited Partnership operates several large mills in Prince George, BC which produce a range of residuals.  The mills burn hog fuel (waste wood from timber processing) to generate power, resulting in large amounts of high-carbon ash that is currently disposed of in a dedicated landfill.  Landfill space is limited, and costs of commissioning new landfill space are very high.  Canfor Pulp and Paper has sought alternative management options for its ash and other mill residuals to reduce costs and improve beneficial reuse of materials. 

To investigate landfill alternatives for its ash, Canfor Pulp and Paper chose SYLVIS to tap our specialized experience in assessing and developing innovative residuals use options.  SYLVIS evaluated several residuals streams produced by the mills, focusing on two types of ash from the boiler systems, and investigated land-based use options. 

SYLVIS conducted specialized sampling and analysis to determine ash characteristics and ensure the material met quality standards for applicable provincial regulations.  Liaisons with the local regulator were made to help Canfor understand the permitting requirements of adopting new ash management strategies.  Column studies were conducted in the SYLVIS lab to evaluate the effect of ash on soil properties and plant growth when used as a liming agent.  Finally, SYLVIS reached out to its network of landowners in the Prince George region to identify potential areas where ash could be beneficially land applied.

The results of the trials showed that Canfor boiler ash has potential for use as a fertilizer and a liming material to improve soil properties and plant growth.  SYLVIS’s work has attracted the attention of local timber farm operators curious about the potential for using ash to improve early tree seedling growth.  As a result of the full options evaluation, land application trials and registration of the material as a fertilizer under the Fertilizers Act are being planned, opening a path forward for the pulp mills to land apply ash to reduce landfill demand and increase beneficial ash utilization.