A study on the annual industrial permeability attenuation phenomena of MBR membrane

Abstract

Defined “industrial permeability VMD” as the permeable volume (m3) of unit membrane area (1000 m2) at unit time (1 day) and unit cross-membrane pressure difference (1 kPa). The VMD is directly calculated by using the daily computer’s records of Xi’an Siyuan A2/O-MBR system. After excluding five anomalies, 71% to 78% of effective industrial permeability was obtained from water yield and cross-membrane pressure difference of 3520 days original data. Each 25 effective industrial permeability was artificially divided into a group unit, and calculated the VMD arithmetic average of the group units. Then, group units are reduced into the annual units. A power equation is fitted into annual VMD arithmetic mean and annual units as the annual industrial permeability attenuation equation. The predicting value of industrial permeability is calculated by the previous attenuation equation, and the measuring value of industrial permeability is calculated by the present attenuation equation. The error ratio is defined as the relative size of the predicted and measured values. Calculating the annual industrial permeability attenuation is straightforward, simple, and convenient. It also show that the prediction period should not be less than three years, so it is best to choose four to five years.

Keywords

• Industrial permeability
• Effective industrial permeability
• Group unit
• Annual unit
• Membrane life prediction