Process simulation, techno-economic evaluation and market analysis of supply chains for torrefied wood pellets from British Columbia: Impacts of plant configuration and distance to market

摘要

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 N-2 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.