Fouling

In the present study the application of the nanofiltration process was investigated mainly in the retention of color and chemical oxygen demand (COD) present in textile industry wastewater. Nanofiltration experiments were carried out in a pilot unit, operating in crossflow. Three different types of

A study of cleaning a Bulgarian UF 60 PAN spiral-wound module was carried out on an ultrafiltration unit (Millipore, USA). Chemical cleaning of the membrane with a 0.25% solution of sodium metabisulfite did not prevent biological fouling. When treated with a 1% solution of formaldehyde, membrane fou

RO plant operators, end-users, membrane manufacturers and system suppliers have been facing two major problems since the advent of commercial membrane technology applications for water desalination utilizing reverse osmosis (RO) and other membrane processes: how to reliably monitor their membrane sy

Nanofiltration membranes (NF) have applications in several areas. One of the main applications has been in water treatment for drinking water production as well as wastewater treatment. NF can either be used to treat all kinds of water including ground, surface, and wastewater or used as a pretreatm

Fouling characteristics of membranes with various molecular weight cut-offs (MWCO) were investigated. The effects of the molecular weights (MW) of humic acids and pre-treatment with PAC on membrane fouling were studied. It was found that the hydraulic resistance caused by fouling materials calculate

Within the lifetime of most membranes some fouling will adversely affect membrane performance and cleaning will be necessary. The cleaning will depend on the type of deposit such as organic fouling, inorganic scaling or colloidal deposition. However strong the circumstantial evidence as to the ident

The use of inorganic membranes in pollution treatment is actually limited by the cost of such membranes. Advantages of inorganic membranes over organic ones are their chemical, thermal and pH resistance. In this study, low cost ZnAl2O4-TiO2 ultrafiltration membranes were tested for removing Cd(NO3)2

In cross-flow ultrafiltration permeate flux has three types of flow regimes. Initially it has a transient regime with a decreasing permeate flow rate. Then it attains a steady state, and the flux reaches a plateau. In the third stage the flow rate becomes independent of applied pressure and is calle

Studies were carried out on the treatment of water for potable purposes using ceramic and capillary membranes. The studies involved the processes of unit microfiltration and ultrafiltration as well as hybrid processes. In the hybrid processes, adsorption on activated carbon and membrane separation w

Two step coagulation using iron coagulant (FeCl3) with anionic polyelectrolyte in the first step and aluminum coagulant in the second one was made to reduce the negative effect of the fouling phenomenon. The process was operated on the commercial scale. The raw water was the blowdown water from the