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Fluff pulp (also called comminution pulp or fluffy pulp) is a type of chemical pulp made from long fibre softwoods. Important parameters for fluff pulp are bulk and water absorbency. Important parameters for fluff pulp are bulk and water absorbency.
Thermally modified wood is engineered wood that has been modified by a controlled pyrolysis process of wood being heated to (> 180 °C) in an oxygen free atmosphere. This process changes to the chemical structures of wood's cell wall components lignin , cellulose and hemicellulose which decreases its hygroscopy and thus increases dimensional ...
The EMC of wood varies with the ambient relative humidity (a function of temperature) significantly, to a lesser degree with the temperature. Siau (1984) reported that the EMC also varies very slightly with species, mechanical stress, drying history of wood, density, extractives content and the direction of sorption in which the moisture change ...
These processes autoclave the treated wood, subjecting it to pressure and heat, along with nitrogen or water vapour to control drying in a staged treatment process ranging from 24 to 48 hours at temperatures of 180 °C to 230 °C depending on timber species. These processes increase the durability, dimensional stability and hardness of the ...
Torrefaction is a thermochemical treatment of biomass at 200 to 320 °C (392 to 608 °F). It is carried out under atmospheric pressure and in the absence of oxygen.During the torrefaction process, the water contained in the biomass as well as superfluous volatiles are released, and the biopolymers (cellulose, hemicellulose and lignin) partly decompose, giving off various types of volatiles. [4]
The raw material is long fibered softwood fluff pulp in roll form. The pulp are defibrized in a hammermill. Defibration is the process of freeing the fibres from each other before entering the papermachine. Important parameters for dry defibration are shredding energy and knot content. Normally an air-laid paper consists of about 85% fibre.
If the wood is placed in an environment at a particular temperature and relative humidity, its moisture content will generally begin to change in time, until it is finally in equilibrium with its surroundings, and the moisture content no longer changes in time. This moisture content is the EMC of the wood for that temperature and relative humidity.
Heat bending is the procedure of bending wood into different curves and shapes using moisture and a bending iron. By placing the wood into water, the moisture and heat from the bending iron will reform the structure of the wood, reorganizing the fibers of the wood to prevent the wood from springing back to its original state. [1]