AWWA WQTC60719

A novel system developed by Long Beach Water Department to provide drinking water qualityby desalting seawater through dual-staged nanofiltration is being evaluated in a TailoredCollaboration project with the American Water Works Association Research Foundation(AwwaRF). The project includes providing the theoretical basis for the system, in particular thegoverning equations that could predict the system performance. The solution diffusion modeland thin-film theory were assessed for their worthiness in providing real-world responses tomeasure system performance. Equations were modified so that permeate and concentratequalities could be determined based on measurable parameters: temperature, operating pressure,feed concentration and flow, membrane area, and the water and salt mass transfer coefficients.Comprehensive bench-scale testing of several nanofiltration membranes were conducted todetermine the mass transfer coefficients and rejection level achieved for the major ions present inthe seawater. The model was used to simulate performance achieved in a 15-gpm pilot plant.The model is able to provide the interplay between finished water quality, energy demand(operating pressure), and recovery and thus provide the demonstrable competitiveness of thisnovel seawater desalination system with conventional seawater reverse osmosis. Includes 2 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

11/15/2004

Number of Pages:

13

File Size:

1 file , 610 KB