I would be interested to learn whether any algal was present in the water that was treated via the UF plant in order to prepare permeate and also at what trans membrane pressure (TMP) the UF membranes ran when the permeate was prepared for the RO plant. In addition, it would be interested to learn whether the water with the extracellular polymeric substances (EPS) was simply clean water that was seeded with EPS or whether it was the same permeate that was seeded with EPS. It is well-known that algal cell breakage occurs at TMP pressures between 0.4 to 0.6 bar. Upon breaking, the algal cells release large amounts of biodegradable organics (AOC/TOC) which significantly accelerate RO biofouling. This could most probably have been the reason why they saw "irresistible" RO membrane fouling as the RO membranes experienced biofouling. The RO membranes could therefore have experienced a different fouling mechanism with the UF permeate than with the water that was prepared by seeding it with EPS. If, however, the same raw water was used for both tests and it was seeded with EPS before treating it via the UF plant, then both water types could possibly have seen high TMP pressures and then the research would be very interesting. Could you please confirm this?

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I would be interested to learn whether any algal was present in the water that was treated via the UF plant in order to prepare permeate and also at what trans membrane pressure (TMP) the UF membranes ran when the permeate was prepared for the RO plant. In addition, it would be interested to learn whether the water with the extracellular polymeric substances (EPS) was simply clean water that was seeded with EPS or whether it was the same permeate that was seeded with EPS. It is well-known that algal cell breakage occurs at TMP pressures between 0.4 to 0.6 bar. Upon breaking, the algal cells release large amounts of biodegradable organics (AOC/TOC) which significantly accelerate RO biofouling. This could most probably have been the reason why they saw "irresistible" RO membrane fouling as the RO membranes experienced biofouling. The RO membranes could therefore have experienced a different fouling mechanism with the UF permeate than with the water that was prepared by seeding it with EPS. If, however, the same raw water was used for both tests and it was seeded with EPS before treating it via the UF plant, then both water types could possibly have seen high TMP pressures and then the research would be very interesting. Could you please confirm this?