Study on the effect of humidity on formaldehyde emission parameters of wood-based panels

Wood-based panels are a significant source of indoor volatile organic compounds (VOCs), crucial for managing indoor pollution. The emissions from wood-based panels are influenced by both intrinsic factors, including their composition and manufacturing process, and extrinsic environmental conditions, such as temperature and humidity. In this paper, the emission of formaldehyde in plywood was studied under different temperature conditions (15°C, 23°C, 32°C and 37°C) and different humidity conditions (40%, 60% and 80%) by environmental chamber method. To understand the influence of relative humidity on the key parameters of panels from a mechanism perspective, this paper investigates the influence of relative humidity on the initial emittable concentration of formaldehyde, based on the hydrolysis reaction of urea-formaldehyde resin. Concurrently, the molecular dynamics and porous panels model were amalgamated to assess the influence of relative humidity on both the partition and diffusion coefficient. To simulate the emission process in a real environment, a control equation that allows for variations in both temperature and humidity is needed. This paper employs the method of variable separation to derive a simplified control equation. Subsequently, experimental data was utilized to validate the derived equation’s effectiveness within the practical indoor environmental range.