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Reverse osmosis (RO) membranes have made a breakthrough in waste water reclamation for the rejection of micropollutants in multiple applications such as reuse. Since these compounds are not completely eliminated using conventional treatments. This paper offers an overview of a waste water treatment plant using RO membrane treatment to study the rejection of 75 micropollutants from different families. The 75 selected micropollutants include some emerging and persistent compounds like volatile organic compounds (52), endocrine disrupting compounds (2), odor compounds (8), fragrance allergens (10), and some pesticides (3). Experimental results indicated that secondary effluents from conventional treatments contained most of the micropollutants studied; showing that conventional treatments such as activated sludge are not able to completely eliminate them. The rejection of these organic compounds was studied after the RO system. In addition, the relation between the micropollutant’s rejection, the molecular weight, and the octanol-water partition coefficients was also evaluated. [ABSTRACT FROM PUBLISHER]

Breakthrough reverse osmosis (RO) membrane chemistry and innovative materials of construction have been developed to achieve highest possible NaCl rejection while maintaining maximum element productivity. Novel brackish water reverse osmosis (BWRO) membrane element delivers to end users state-of-the-art salt rejection (99.7%) at 30% lower energy consumption compared to current high rejection BWRO membranes in addition to tailored salt passage reduction of critical solutes as nitrate, boron, silica, and ammonium. The novel module component, low differential pressure (LDP) feed spacers, provide end users with up to 15% savings in direct RO energy reductions via the lowest feed-side pressure drop available in the market. The LDP spacer outperforms other spacers by reducing pressure drop while maintaining high active area and a unique BWRO element with productivity up to 14,000 gallons per day has been achieved. A financial analysis was carried out with a refined cost model using different economic frame conditions. It shows RO plant energy costs can be reduced by up to 30% in industrial applications without compromising the product water quality. In SWRO application, the size of the BWRO pass can be reduced by 19%, resulting in an overall water cost reduction of 0.53 UScts/m³ produced water. [ABSTRACT FROM AUTHOR]

Norwegian lake water treatment is dominated by cellulose acetate (CA) membranes, which serve approximately 3% of the population. The quality requirements for potable water are becoming stringent and Dow Water & Process Solutions has suggested nanofiltration (NF) as a suitable technology replacement in cases where CA membranes fail to meet the quality limits. This paper discusses the operating experience of the first CA plant retrofit trial in Norway, where the treatment goal was to remove color, organic matter and bacteria from surface lake water to produce potable water for the community. The project has shown that nanofiltration membranes can provide excellent water quality in terms of color, bacteria and an overall TOC rejection (98%). The end user reports a clear improvement in the water quality compared to CA membranes. The trial was executed with minimal modifications to the existing plant. This paper focuses on evaluating the feasibility of the current set up and gives recommendations on further process optimization in terms of improving pre-treatment and cleaning, as well as the cost evaluation of the recommended modifications. [ABSTRACT FROM AUTHOR]