Comparative Life Cycle Assessment of Heat-Treated Radiata Pine Lumber: Evaluating Two Heat Supply Scenarios in China

Wood heat treatment is considered by many to be an eco-friendly wood modification method, given that only heat is applied during the treatment. However, it is essential to recognize that energy consumption can give rise to various environmental challenges. Quantitative evaluation of the environmental performance of a wood modification technology is always a challenge faced by the wood processing industry. To perform a comprehensive assessment, it is imperative to adopt a life-cycle-based approach, which is still very limited for heat-treated wood in China. This study investigated the mass and energy consumption of heat-treated radiata pine lumber in life cycle stages from forest management in New Zealand to wood heat treatment in East China and calculated its environmental impacts using the ReCiPe method. Two heat supply scenarios, i.e., on-site wood-fired boilers and off-site coal-fired power plants, were compared to evaluate the influence of national policy on environmental performance. Transoceanic shipping and lumber drying were found to be the life cycle stages dominating the environmental impacts level, and human-health-related impacts, mainly fine particulate matter, photochemical ozone formation, human toxicity, and global warming, were the major environmental impacts of heat-treated radiata pine lumber. With on-site heat supply, more heat and electricity were consumed due to a lower boiler efficiency and more energy demands. However, the impact assessment showed lower environmental impacts in this scenario. The non-fossil and carbon-neutral nature of wood is the key to the environmental advantages of this heat supply scenario.