Wood and Furniture Industry
The demands on the wood and timber industry are diverse and sophisticated. In this industry, different energy sources are used for the purpose of convective wood drying. LPG is considered as the economic fuel for direct-fired accelerated drying kilns coupled with all the environmental advantages it provides.
Within the industry, the process of thermal modification (of wooden materials) is performed at temperatures of up to 230°C. The primary energy source for air heating is LPG as it is creates more water during combustion.
Water from LPG’s moist heat is important because it is used for conditioning the wood by helping to achieve an even and correct balance of drying and vapour absorption. Excessive drying leads to cracked wood whilst excessive absorption hinders drying. Further still, uneven drying leads to discoloration and wood properties are temperature sensitive.
The preservation of timber against microorganism and insect attacks requires that solutions of chemical insecticides or wood preservatives penetrate through the wood surface into the sub-surface layers.
Insecticides and fungicides are soluble in a variety of petroleum solvents, a large of which are subject to certain disadvantages. The less volatile solvents in particular (e.g. gas oil) result in substantial quantities of residual solvent in the timber, which hinders wood preservation, sometimes interfering with painting and further surface treatments.
It could also cause delays due to the extra procession and can result in changes in the physical properties of the wood as well as losses of active preservative and treating agents.
Furthermore, penetration of the timber depends strongly on solvent viscosity and both water and numerous petroleum solvents prove unsatisfactory in that respect. The use of LPG as a solvent for timber preservatives results in superior impregnation, complete solvent removal on completion of treatment, solvent –free surfaces suitable for painting and a minimum of dimensional changes during and after treatment.