Mechanical and physicochemical contribution in removal of different soil types on cotton fabric

Abstract

The research was conducted to identify the optimal washing methods for three types of soils, in terms of washing efficiency and eco-efficiency. To this end, the mechanical action by the washer’s agitation and the physicochemical action by detergents were investigated for their respective contribution to the detergency of three kinds of artificial soils: oil, protein, and their mixture. In general, washing efficiency increased with the increased agitation speed and the amount of detergent use. Most of the washing conditions presented a positive synergistic effect when both the mechanical and physicochemical actions were applied simultaneously. The contributing ratio of the physicochemical action was greater for oily soil than for other soil types, due to the effective rolling-up by the detergent for the oily soil. The contributing ratio attributable to the mechanical action was higher when the protein was present in the soil composition, and the mechanical contribution was compromised as detergent usage was increased. The washing condition with the largest synergy did not always correspond with the condition of the highest washing efficiency. Energy Efficiency for Detergency was increased in all soil types as the agitation speed increased. It is suggested that the washing method be determined considering (1) the level of soiling and the acceptable washing performance, (2) the synergistic effect of mechanical and physicochemical actions, and (3) the eco-efficiency of washing methods.