Optimization and recovery of caustic soda from the mercerization process:Case of the Almeda textile factory

Abstract

Experiments were conducted to evaluate the operational parameters of an evaporative unit which concentrates dilute caustic soda present in the wastewater from the mercerizing operation unit of Almeda textile factory. The concentration of caustic soda for the mercerizing operation was optimized before the recovery and an optimum concentration of 20-23% was attained. This was carried out by evaporating the water from the dilute solution collected from the mercerizing effluent. Parameters including the amount of mass condensate, the amount of mass concentrate, temperature, evaporator pressure, heating steam supply pressure and concentration change were measured. From these, the rate of evaporation, and concentrating capacity of the evaporation was determined. From the experiments, it was concluded that the rate of evaporation should be maintained at an average of 5.71 kg/h, for the caustic soda recovery.