Organic trap

Organic traps contain isoporous, macroporous, or other specifically designed resins (such as reticulated, cross-linked polystyrene resins devoid of ionic function) and take up organics by a combination of ion exchange, adsorption, and other mechanisms. They typically are installed to precede the DI plant. 

Activated carbon filters remove a wide range of organic matter by adsorption onto the carbon bed. The bed may be derived from a number of different carbon sources, and the correct selection of bed type, capacity, and porosity is a specialized function. Activated carbon may be usefully employed in organic traps, complementing the resin bed, but its capacity and organic removal rate characteristics are flow-dependent. Excessive flows may compromise the rate of adsorption of organic matter. 

Organic traps (ion-exchangers) may be more suitable where the organic loading is high. Ultrafiltration and RO may also prove suitable alternatives. 

Where an organic trap is part of a demineralization plant system, it is placed in the train upstream of the strong base anion (SBA) resin unit. When the organic trap resin is placed within the same pressure vessel, physically on top of the anion resin (stratified bed), in which case, as it forms part of the overall anion capacity, a weak base anion resin operating in the free base form is employed. 

Organic trap designs are available that employ a combination of activated carbon and cross-lined resin beads without ionic functionality. 

Liquid face velocity rates, in organic traps 324... 

Subscripts 1, 2, 3 and 4 relate to p-Ps, free e+ and o-Ps in the aqueous and organic (trapped Ps) subphases, respectively erf is the error function. It has been shown, in the case of Ps trapping in micelles, that a physically satisfactory analysis of the PALS spectra is obtained by using Eq. (21) with the Ps bubble radius, not with the free Ps radius [98], For usual, smaller solutes reacting with Ps, the difference between kD and kD(t) should not be very large, as may be inferred by averaging Eq. (20) over time. 

The operating characteristics of an organic trap or organic scavenger unit are generally as follows ... 

Reverse Osmosis(RO) UfrafilfraHon(UF) Media Filfrafion Organic Trap(OT)... 

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