Abstract
Improving economic competitiveness is the key for sustainable development of the wood pellet industry. To support this development, we have carried out a comprehensive techno-economic evaluation of five possible process configurations for production of conventional (CWP) and torrefied (TWP) wood pellets in the Canadian province of British Columbia (BC), based on process simulation with multi-scale models involved as illustrated in the graphical abstract. A novel heat integration strategy is proposed for the TWP production process to avoid the use of N2 and achieve auto-thermal operation. In comparison with CWPs, producing TWPs in the operating sequence drying, torrefaction, grinding, pelletization can reduce production costs by about 10% and reduce delivered costs to both domestic and overseas markets by about 20%. It is essential that the TWP plant is located in a region with abundant and low-cost feedstock, low electricity price, low labor cost, and efficient distribution logistics. Due to the low capital cost contribution (10%), torrefaction could be implemented by either building a new plant or upgrading an existing conventional pellet plant. The market analysis reveals that the future market for TWPs from BC is expected to lie outside Canada, in the Asia Pacific region, and Europe, unless significant domestic policy measures are introduced to promote Canadian use of TWPs.
•Torrefied wood pellets (TWP) costs 20% less than conventional pellets over supply chains.•BC pellets are expected to lie outside Canada, especially in the Asia Pacific region.•The best pathway to produce TWPs is drying- > torrefaction > grinding- > pelletization.•TWPs can be produced auto-thermally without N2 and catalyst.•The critical production costs for TWPs are raw material, electricity, and labor.