Microwave wood modification: a method for conserving timber for its sustainable utilization (original) (raw)

2018, IBC Book of Abstracts, 2018

Despite the availability of synthetic substitutes such as plastic, wood is highly preferred by several consumers, primarily due to its versatility. Wood is one of those very few natural resources available that can be renewed and reconstituted and hence has cut a niche as a raw material for a number of end uses. Further its renewability, aesthetics, ability to sequester carbon (CO2), and natural origins are among the features making it an attractive alternative to the stakeholders. However, rapid depletion of forests for household and industrial purposes in the present century has made this resource dearer. The country for several years now is dealing with an acute crisis and paucity of timber and the fissure between supply and demand is ever increasing. In view of the above complications, the pressure is more on imported timber species because of the ban on felling of natural forest trees. These are mostly non-durable in nature, hence requires protection to improve its durability for a sustainable use, which in the long run aids in conserving the biodiversity of the forest lands as recycling period of wooden materials increases, with increased durability. However, it has been found that some non-durable species are refractory in nature too and hence cause hindrance in woodworking operations. Microwave wood modification is an eco-friendly technique, that predominantly aims at diminishing the energy consumption for several woodworking operations by amalgamating exhaustive and time-consuming process parameters like seasoning and pre-treatment prior preservation, which make it energy efficient and green, improving wood permeability and preservative uptake simultaneously, resulting in its sustainable use for eons. In the present study, the effects of microwave radiation, exposure time and initial wood moisture content (IMC) on the retention and permeability of Tectona grandis and Southern Yellow Pine wood specimens of imported origin are examined. The experimental study on MW modification at 2.45 GHz frequency and 112.65 WCm–2 intensity for 4, 4.5 and 5 mins respectively, followed by dipping in preservative CCB for 5mins, revealed a substantial increase in wood impregnability and retention. Tectona grandis specimens were however subjected to pressure treatment separately to achieve an optimum range of retention. Retention values obtained of 7.09 Kg/M3 and 8.15 Kg/M3 for SYP and teak respectively were found suitable for interior uses. However, samples subjected to higher time periods showed significant charring and checks