Fouling biological

Tributyl(tetradecyl)phosphonium chloride was developed specifically (26,27) as a broad-spectmm biocide for the control of biological fouling in cooling water systems where it is particularly effective (see Industrialantimicrobialagents). 

Other than grooving, localized attack due to ammonia is relatively rare. Patches of attack can occur in conjunction with biological fouling emd decomposition of organic materials, which generate ammonia. 

Biological fouling biological organisms attach to heat transfer surface and build a surface to prevent good fluid contact with the tube surface. 

Walko, J.F. Controlling Biological Fouling in Cooling Systems- Part I," Chemical Engineering, Oct. 

Biological fouling was monitored using the customary indicators of RO performance, including flux (productivity), salt passage, and bundle pressure drops (AP). In addition, the total bacteria count (TBC) of the RO feed water and the reject brine stream were also obtained using the membrane filtration method (Ref. 6). The increase in TBC between the feed and reject portions of the system had been found in the preliminary stages of... 

Influent streams with pHs greater than 11 or less than 5 may corrode system components. Biological fouling may also occur. 

Fouling material biological fouling colloids scaling organics metal oxides proteins... 

The timber used in this type of cooling tower is commonly pressure-treated redwood, Douglas fir, and other wood species, the preservative being chromated copper arsenate or, more usually today, acid copper chromate. Despite the wood preservative, it is not uncommon to find wood decay and biological fouling of the plenum area and drift eliminators. 

Dow Chemical Company, "Water Chemistry and Pretreatment Biological Fouling Prevention," form no. 609-02037-1004. 

Hydrogen peroxide or a combination of hydrogen peroxide and peracetic acid can be used to address biologically fouled RO membranes when operated at lower pH. The following precautions should be taken when using hydrogen peroxide ... 

Figure 8. Biological fouling on shell of banded dye-murex (6). (Reproduced with permission from Ref. 21. Copyright 1982 Weizmann Sci Press.)...

Membrane storage Einally at the end of washing, the membrane was stored in 0.5% solution of sodium metabisulhte (SMBS) preservative prepared in DM water. This helps to prevent biological fouling and irreversible destruction of the membrane. 

Biological fouling caused by growth of microorganism (slime) can be removed by preparing a bleach cleaning solution ... 

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