Electro-osmotic dewatering of high moisture flax stems

Retted flax stems contained high amounts of water from the pre-soaking and retting processes. Electro-osmotic dewatering was investigated as a pre-drying process for high-moisture flax stems using a bench electro-osmotic roller press. The various parameters affecting electroosmotic dewatering were cylinder pressure (1000kPa-3000kPa), applied voltage (12V-36V) and pre-soaking time of the flax stem (12 h-36h). An experiment was designed using central composite design. From the experiments, a maximum of 38.34% of the total water contained in the stem was removed using 12h soaking; 1000kPa cylinder pressure and 36V applied voltage during the electro-osmotic treatment. For a given soaking time, at 36V with 3000kPa cylinder pressure the maximum water removal occurred. The electro-osmotic permeability of the stems at various conditions was studied. In all the treatments, electro-osmotic permeability ranged between 3.32×10^-5m²V^-1s^-1 and 1.22×10^-4m²V^-1s^-1. Electro-osmotic permeability was found to increase with increasing water removal and decreased with increasing applied voltage.