AWWA ACE60079

This paper presents a discussion of two main approaches for selecting a nanofiltration (NF) or reverse osmosis (RO)technology and a method for cost comparison over a full life cycle. The first approach isto use NF membranes, which operate at low feed pressure, but provide less contaminantrejection. Using this approach, the degree to which blending can be used is limited andoverall horsepower required for treatment remains high. The second approach is to useRO membranes, which operate at high pressure, but provide high contaminant rejection,and therefore reduce the volume of treated water required to produce a specified blendedfinished water quality. This paper shows that RO in certain cases may be more cost-effectivethan NF. This is due in part to the fact that RO product waters in many casesmay be blended to a greater extent than NF product water. Greater blending may alsoallow for a reduction in capital and subsequent O&M expenditures.This paper presents a study of the impacts of these factors on full life cycle costs.Considerations are given to capital costs associated with a new membrane plant, feedwater quality, finished water quality goals, membrane technology (NF vs. RO), pressureenergy requirements, rejection, the degree of blending, and the amount of systemrecovery that can be achieved. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

06/17/2004

Number of Pages:

12

File Size:

1 file , 590 KB