We investigated seasonal variation in membrane fouling in membrane bioreactors (MBRs) treating municipal wastewater regarding the difference between physically reversible and irreversible fouling. Two separate MBRs with different solid retention times (SRTs) operated in parallel for about 200 days including high- and low-temperature periods to evaluate the effect of operating conditions on seas...

• Pd-Sn and Pd-In catalysts have emerged as competitive alternative to Pd-Cu pair. An excess of promoter or noble metal provoke adverse effects on catalytic denitrification. Fouling leaching are considered the main causes catalyst deactivation. Regeneration processes been developed provide new life deactivated catalysts. Nitrate (NO 3 – ) pollution water bodies is a serious environmental proble...

One of the most costly problems in the maintenance of heat exchangers is de-fouling, which results in a waste of time and money. The present study includes two parts: the first section addresses fouling factor, its disadvantages, and circumstance of formation, fouling types, and general models of the fouling. In the second part, the problem of fouling in oil exchanger and particular type of fou...

This paper provides a review on the fouling mechanism and its effect onto the performance of finned tube heat exchangers in HVAC systems. Fouling tends to degrade the performance of heat exchangers by decreasing the heat transfer coefficient and increasing the air-side pressure drop across the heat exchangers. Air side fouling depends on a number of factors on the air side, including type and c...

The membrane fouling index, widely used in the reverse osmosis (RO) membrane industry, is developed mainly to assess the fouling potential of particulate matter. However, the fouling potential by organic matter should also be accurately evaluated as the productivity loss by organic fouling is often more severe than particle fouling, despite its low concentration in feed water. This study was pe...

The combined fouling during ultrafiltration (UF) of surface water pretreated to different extents was investigated to disclose the roles of polysaccharides, proteins, and inorganic particles in UF membrane fouling. Both reversible and irreversible fouling decreased with enhanced pretreatment (biologically active carbon (BAC) treatment and sand filtration). The sand filter effluent fouled the me...

The Propose of this paper is to introduce a new model for crude oil fouling in preheat trains of crude distillation unit. The experimental results of Australian light crude oil with the tube side surface temperatures between 200-260 oC and fluid velocity ranged 0.25 to 0.4m/s were used. The activation energy of chemical reaction depends on the surface temperature has been calcula...

We investigated effects of microfiltration (MF) on heat transfer fouling tendencies of thin stillage. A stainless steel MF membrane (0.1 micron pore size) was used to remove solids from thin stillage. At filtration conditions of 690kPa, the MF process effectively recovered total solids from thin stillage. Thin stillage was concentrated from 7.0% to 22.4% solids with average permeate flux rates ...

Membrane bioreactors (MBRs) are advanced tools for biological wastewater treatment to obtain high-quality treated water using ultrafiltration or microfiltration membranes for solid–liquid separation2). Despite their advantages over the conventional activated sludge method, a major challenge associated with the use of MBRs is membrane fouling, which involves the clogging of membrane pores due to...