AWWA MTC57574

Each water treatment plant design requires consideration of numerous criteria to determine the optimum process for the unique application. The selection of low-pressure membrane systems is no different. This paper presents the design considerations and general needs for successful low-pressure membrane system selection. There are several options to consider when evaluating low-pressure membrane filtration as a potential solution. Today, there are a range of low-pressure membrane systems available with varying membrane chemistry, pore size, module configuration and operating restrictions. Each membrane process has specific operating characteristics inherent to its unique properties. For each application the overall system design and the scope of work required from the system supplier are equally important in the selection process. The evaluation process needs to determine the critical operating parameters such as flux, trans-membrane pressure (TMP), backwash interval, chemical cleaning process and frequency, waste volume, and coagulation chemistry, if required, for successful scale-up operation of the full-scale system. The full-scale system should be based on a pilot test or representative data for the specific membranes that will be applied. There are other factors to be evaluated that are not easily quantifiable. A key consideration is the method to monitor membrane integrity and the ease of detection, isolation and repair of individual fibers or modules. Other considerations are robustness of the system design, availability of local service, and process support capability in the event of an unusual process upset. The evaluation should also consider the compatibility of the system to accept technological improvements. Includes 3 references.