AWWA WQTC58887

There has been tremendous growth in both the size and number of low-pressure membrane filtration systems in the United States. Not only is there growth in the size of new facilities and the number of new facilities in the United States, but there is also tremendous growth in the diversity and number of available membrane products. While the variety of available membrane products makes the technology available through most applications, it has complicated the membrane selection process. While membrane pilot studies can be performed to evaluate the performance of applicable systems, limitations in funding, availability in space and time can limit the number of membrane pilot systems that can be tested. Because each membrane product has its own strengths and limitations, a careful evaluation of the intended use and available system must be performed. This being given, it is critical that an appropriate selection framework be used in order to select the appropriate systems for pilot testing. The criteria selected for this evaluation of membrane systems should be developed based on site-specific conditions. Critical elements in this evaluation include: project definition including membrane feed water characteristics and physical constraints; available systems including system configuration and compatibility; costs including capital, operation, maintenance, and membrane replacement; and, supplier experience. While capital cost estimates and experience can be solicited directly from suppliers, the other critical factors need to be carefully evaluated. Choosing a subset of the available systems to evaluate on the pilot scale is critical to the success of a project. In order to choose a proper subset, adequate data must be available to define the application. Elements of project definition can be classified into three broad categories: feed water quality, site constraints, and finished water quality goals. The definition must then be linked to membrane and system properties that best fit the application. Two common scenarios are used as case studies in the paper. Includes 2 references, tables, figures.