ABSTRACT
This chapter includes methods of fouling analysis, and cleaning. The "concentration polarization" refers to the concentration boundary layer adjacent to the membrane within which there is elevated concentration of all rejected and partially rejected components. This is true for reverse osmosis (RO), ultrafiltration (UF) and microfiltration (MF). For both MF and UF, the separation is achieved through basic sieving mechanism, with rejection of molecules whose size is greater than that of the pores. Whether fouling is on the membrane surface or in the pores, it will affect flux relationship in different ways and this will be considered in mathematical manner later. While membrane processes apparently offer simplicity, operation of membrane processes often requires know-how due to the complications of fouling. With process fluids and industrial timescales, fouling of membranes can be considered to be inevitable. Membrane fouling is combined effect of a number of physical, chemical, and biological processes, which all lead to an increase in overall resistance to permeation.
