AWWA MTC64587

The City of Natchitoches, Louisiana uses the water from Sibley Lake for their potablewater supply. The water from the Lake is high in Total Organic Carbon which is thesource of precursors to disinfection byproducts. The City has had a history of regulatorynoncompliance for haloacetic acids. The objective of this Integrated Membrane System(IMS) pilot study was to determine the most effective and efficient process for upgrade ofthe existing treatment plant using membrane technology. A bench scale procedure was conducted first to screen the membrane types and removalcapabilities needed for the larger scale pilot plants. The large scale (20 GPM) pilot plantstreated water from both raw lake water and clarified water using alum and lime. HollowFiber Ultrafiltration membranes followed by Spiral Wound Nanofiltration membraneswere evaluated on both feed water sources. In addition, the use of Spiral WoundNanofiltration membranes on the existing plant's finished water was evaluated.The study points out the need for pretreatment in order to protect and extend the life ofmembranes.Molecular weight cut-off is a critical consideration for selection of membranes from astandpoint of variations in make-up of different source waters. Variations in compoundsizes can play a major role in selection of membrane types for the most effectivetreatment of a particular water source. All operational parameters used for systemevaluation and design considerations are presented.The advantages of membrane technology versus conventional treatment methods include:reduced operational and maintenance requirements by way of highly automated processequipment; high efficient removal of unwanted compounds; and, added bonuses such asreduction in unregulated parameters: taste, color, and odor. Through the promulgation ofnew more stringent water quality standards, membrane treatment is becominga feasible alternative for water treatment due to the nature of this process.The paper includes pilot plant data, process evaluation and feasibility. A detailedengineering evaluation and cost estimate with the intent toward facility design andconstruction is presented. Includes 4 references, tables, figures.

Product Details

Edition:

Vol. - No.

Published:

03/01/2007

Number of Pages:

20

File Size:

1 file , 440 KB