🌍💼 Can pharmaceuticals be effectively removed from water and wastewater in treatment plants using reverse osmosis and nanofiltration? 📉...
Published on by Hossein Ataei Far, Deputy Manager of the Research, Technology Development, and Industry Relations Center at NWWEC
🌍 Low-pressure MF and UF adsorb some hydrophobic compounds. RO and NF remove >85% of NSAIDs from groundwater. Removal involves adsorption, electrostatic effects, and sieving, affected by factors like size, charge, and membrane properties. Electrochemical oxidation combined with membranes improves pharmaceutical (pharma) elimination. NF and RO remove more pharma compared to micro- and ultrafiltration, depending on properties and operating conditions.
🔎 Nanofiltration
▶️ NF can remove more than 90% of pharma from water and wastewater, but its effectiveness varies depending on the compound.
▶️ The rejection efficiencies of negatively charged pharmaceuticals are higher than that of neutral pharmaceuticals. During sulfamethoxazole and carbadox nanofiltration, the rejection efficiency increased from 90% to 95% due to membrane charge repulsion when both antibiotics became negatively charged at pH > 5.6.
🔎 Pros and cons of Nanofiltration:
Pros :
▶️Remove efficiently organic pollutants (e.g.,
pesticides, dyes and
pharmaceuticals)
▶️Also applicable for inorganics (heavy metal) removal.
cons:
▶️High operational costs
▶️High energy demand, membrane fouling, and disposal issues.
▶️Limited application in pharmaceutical removal.
▶️Not fully effective in removing some ECs as pore sizes vary from 100 to 1000 times larger than the micropollutants.
🔎 Reverse Osmosis
▶️RO effectively removes many pharma (>90%), but low removal has also been observed for ketoprofen (64.3%) and diclofenac (55.2–60%). Carbamazepine, clofibric acid, caffeine, diclofenac, naproxen, and propylphenazone were removed (>95%) from water.
▶️Pharmaceutical rejection mechanisms depend largely upon both membrane material and the physicochemical properties of the pharmaceutical.
▶️Concentrate (brine) with elevated levels of pharma and low-molecular-weight organics, such as acetaminophen have proven to be problematic for high-pressure membranes.
🔎 Pros and cons of RO:
Pros :
▶️Reduction in wastewater volume.
▶️Remove PCPs, EDCs, and pharmaceuticals efficiently. More than 90% of large EDCs removed.
cons:
▶️High energy costs.
▶️Membrane fouling.
▶️Difficult to handle residual concentrate.
🌍 Conclusion:
Overall, NF and RO are the most effective processes for pharma removal from water and wastewater, but they have their limitations and associated challenges.
#Pharmaceuticalrejection
#Ultrafiltration
#Nanofiltration
#ReverseOsmosis
#WaterTreatmentPlants
#WastewaterTreatmentPlants
🔗 Reference:
Patel, M., et al. (2019). Chemical Reviews.
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Figure: Consumption pattern of different pharmaceuticals around the world -
Ref.: IMS., MIDAS database, 2013