Remediation of laundry wastewater with a low-pressure aromatic polyamide thin-film composite reverse osmosis membrane for membrane fouling minimisation and reuse application

In areas with limited freshwater resources, affordable technologies can remediate greywater for reuse applications and increase the water supply. These wastewaters contain various chemicals, which make them challenging to treat. Reverse osmosis (RO) membrane systems could be the solution to removing these harmful chemicals. Membrane fouling has been investigated and using a commercial antiscalant to treat laundry wastewater effluent with a polyamide (PA) thin-film composite (TFC) reverse osmosis membrane. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR),energy-dispersive X-ray spectroscopy (EDX), and scanning electron microscopy (SEM) were used to assess the antiscalant effects. The anionic surfactant rejection was above 99.8% for experimental tests conducted. The average COD removal rate was in the range of 91-96%, irrespective of the antiscalant dosing. However, the presence of antiscalant at the dose of 8 mg/dm3 significantly reduced fouling intensity. The flux decline ratio amounted to 56 and 72% for the RO process with antiscalant and no antiscalant dosing, respectively.