Laundry wastewater treatment using ultrafiltration under different operating conditions

Abstract

The laundry wastewater of one of the hospitals in Qatar was selected and studied. It was found that hospital laundry is releasing considerable amount of wastewater i.e. 1800 - 2500 liters/cycle while washing 40 - 50 kg of laundry items. The wastewater characterization showed that the laundry effluent was polluted enough to cause environmental pollution if not treated properly. Single step membrane technology i.e. ultrafiltration membrane with lower molecular weight cut-off (MWCO) of 5kDa was used for the treatment of laundry wastewater. It was found that the one step treatment is enough to remove most of the pollutants in terms of COD, Surfactants and suspended solids could be rejected while maintaining acceptable permeates flux. The treated water was found to be complying with different standards of wastewater reuse considered in this study. Effect of different operating parameters like pressure, temperature and flow rate on membrane rejection and permeate flux was also investigated. The in-depth studies of variation in wastewater characteristics and also reuse tests (using treated water to wash clothes) were recommended for further verification of potential of proposed technology.