The implementation of circular economy in wood industries is an effective way for future sustainable development. The wood industries in China are not in the direction of circular economy approach due to less availability of assessment/calculation data of pollutants as per life cycle assessment (LCA) criteria. The present study focuses on the calculation of emission and pollutants from wood industries as per LCA; the emission and pollution data were collected from fiberboard Medium-density fiberboard (MDF), plywood and particleboard (PB) production. The comparative analysis of dust emissions, industrial waste gases and chemical oxygen demand (COD) were performed among three wood industries. The results revealed that the fiberboard industry was the highest emitter of dust, industrial waste gas and COD; and particleboard industry was the least emitter. Further, results indicated that pollutant index of wood industries were significantly changed between 2015 and 2017; the industrial waste water discharge increased five folds and the COD, dust and industrial gases increased two times. This study provides with the emission and pollutants data of wood industries as per LCA to promote the sustainable development for circular and low carbon economics.
Wood decay is an economically significant process, as it is one of the major causes of wood deterioration in buildings. In this study, the decay process of Scots pine (Pinus sylvestris) samples caused by cellar fungus (Coniophora puteana) was followed by nuclear magnetic resonance (NMR) spectroscopy and magnetic resonance imaging (MRI) methods. Altogether, 30 wood sample pieces were exposed to fungus for 10 weeks. Based on the decrease of the dry mass, the samples were categorized into three classes: decomposed (mass decrease 50–70%), slightly decomposed (10–50%), and nondecomposed (<10%). MRI made it possible to identify the active regions of fungus inside the wood samples based on the signal of free water brought by the fungus and arisen from the decomposition of wood carbohydrates. MRI implies that free water is not only created by the decay process, but fungal hyphae also transports a significant amount of water into the sample. Two-dimensional 1H T1-T2 relaxation correlation NMR measurements provided detailed information about the changes in the microstructure of wood due to fungal decomposition. Overall, this study paves the way for noninvasive NMR and MRI detection of fungal decay at early stages as well as the related structural changes.
In this study, the effects of rubberwood extractives on the mechanical properties and fungal decay resistance of rubberwood-based wood plastic composites (WPCs) were explored. Three different solvents, benzene-ethanol, methanol, and deionized water, were used to remove the extractives of the rubberwood flour (RWF). The surface topographies of the prepared rubberwood-based WPC and the rubberwood itself were characterized using digital instruments and scanning electron microscopy (SEM). The results indicate that the mechanical properties of the WPC prepared using extracted RWF were higher than those of the WPC prepared with unextracted RWF. The sequences of resistance to the growth of mold on the surface of the WPC were ranked as follows: deionized-water-extracted WPC > methanol-extracted WPC > benzene-ethanol-extracted WPC > unextracted WPC. The WPC made with extracted RWF had better brown-rot resistance and worse white-rot resistance than the unextracted WPC. These results demonstrate that the removal of rubberwood extractives has a positive effect on the mechanical properties and mold and fungal decay resistance of rubberwood-based WPCs.