Pharmaceutical wastewater treatment using direct contact membrane distillation

Abstract

Most of the pharmaceutical industrial waste is transported off-site for treatment or incineration, both of which are typically costly and environmentally harmful. This study explores the feasibility of using membrane distillation (MD) to treat pharmaceutical industrial waste stream, aiming to meet the discharge standard before disposal into the sewer. Specifically, direct contact membrane distillation (DCMD) process was identified as an effective method for handling high salinity, high boron pharmaceutical waste stream from a local pharmaceutical manufacturer. Several commercially available hydrophobic membranes were tested with the real wastewater samples. Among the membranes tested, the performance of PTFE membrane was found better compared to PVDF and PP membrane, in term of the flux (~7 LMH) and rejection (>99 %). The DCMD process successfully removed over 99 % of sodium, potassium, phosphate and boron, meeting discharge standards. The study also explored various membrane regeneration strategies, including in-situ chemical cleaning and warm air drying. An economic analysis revealed potential saving of 19–34 % when using membrane treatment compared to incineration. Overall, the study demonstrated the effectiveness of MD for treating pharmaceutical wastewater, ensuring it meets discharge quality and reducing incineration volume. This research serves as the foundation for future investigations into MD processes within the pharmaceutical industry.