Pretreatment is the center of textile wet processing. Most of the Textile Companies are using a combined pretreatment process with exhaust and semi-continuous method. After the treatment is over, the bath with residual chemicals is drained out into the effluent treatment plant. In this study, an attempt has been made to reuse the residual chemicals by replenishing the measured amounts of chemicals again for the combined pretreatment process.
In the case of the pretreatment process in a Jigger machine, the liquor is drained out with residual chemicals, then the concentrations of H2 O2 and NaOH were assessed in that. In the case of pad-roll bleaching, the fabric roll is rotated in the steaming chamber for twelve hours and washed in a counter-current washing machine, then the concentration of chemicals was analyzed after washing is over. Based on the chemical analysis results, by replenishing with measured amounts of chemicals, pretreatment is done in both laboratory scales repeatedly up to four times without changing water, and on the bulk production; it has been done by mixing used water and freshwater. Various factors such as absorbency, whiteness, yellowness, and the effect in subsequent reactive dyeing and pigment printing was evaluated.
Based on the results, it can be concluded that pretreatment liquor and wash liquor can be reused in the pretreatment process of cotton instead of freshwater. The pretreatment liquor and wash liquor can safely be reused after replenishing with measured amounts of H2O2, NaOH, and other auxiliary chemicals based on the analysis results for the scouring-bleaching purpose of the next batch with satisfactory bleaching, printing, and dyeing performance.
Read More: Recycling of Liquid waste for effective and satisfactory Pretreatment in Cotton wet Processing
Pretreatment process in a jigger machine
Pretreatment and chemical analysis of pad-roll bleaching
Effect in reactive dyeing and pigment printing
Reusability of pretreatment liquor and wash liquor
Factors in bleaching printing and dyeing performance