A Study on the Verification of Inlet Structural Improvement of Side Stream Typed Low Pressure Membrane Module Using PIV Method

Abstract

Objectives:The purposes of this study are to suggest a method to distribute the flow rate into the overall vessel vertically and evenly by improving the inlet hydraulic structure of the side stream type low pressure membrane module. Methods:For those, particle image velocimetry (PIV) technique was used to measure the evenness of flow rate distribution in both of the existing full scale single baffled inlet structure and the improved membrane module inlet structure (double baffled). Results and Discussion:As a result, it was confirmed that the flow distribution of the double baffled inlet structure is improved in comparison to that of the existing single baffled inlet structure. In the case of double baffled inlet structure, the instantaneous velocity distributions of 3, 4, and 5 seconds showed a velocity distribution close to the mean velocity of 0.03 m/s in the entire flow field. Also, a maximum velocity of 0.06 m/s was about 60% less than that of the single baffled inlet structure case (0.13 m/s). Conclusion:When the horizontal flow was observed, it decreased by about 300%. Those were 0.008 m/s for the double baffled inlet structure and 0.027 m/s for the single baffled, respectively.

Keywords

• side stream
• membrane module
• inlet structure
• double baffle
• piv