Pore characteristics are likely the most important parameter affecting the removal efficiency and flux/fouling behavior. Low cost microfiber nonwovens with diverse functionality, controlled characteristics, and enhanced flux offer many opportunities in microfiltration process. However, many limitations for nonwovens exist in microfiltration applications: they are relatively coarse pore size, wide pore size distribution, depth filter structure with tortuous pore path through the thickness, hydrophobic nature of melt processed fibers, high specific surface area, and rough surface. If the nonwovens are produced within the pore size range of the MF, the effluent quality or the removal efficiencies is expected to be similar to the typical microfiltration membranes with the help of the dynamic membrane formation. However, fouling problems such as flux reduction and flux recovery after backwash still remain as the major drawbacks during long-term filtration.…