Xylene, aeration

According to the vendor. Microbial Fence has been used to treat groundwater contaminated with polycyclic aromatic hydrocarbons (PAHs) benzene, toluene, ethylbenzene, and xylenes (BTEX) and volatile organic hydrocarbons (VOCs) at petroleum, chemical, and wood treating facilities and manufactured gas plants. Microbial Fence was used alone or in conjunction with soil venting/bioventing, aquifer aeration, pump-and-treat methods, and/or recovery of non-aqueous-phase liquids (NAPLs). 

Biodegradation can be accelerated in a prepared bed reactor with forced aeration. These reactors (Figure 1.2) are used at many Superfund sites for bioremediation of PAHs and BTEX (benzene, toluene, ethylbenzene, and xylene) (Alexander, 1994). This method, with recirculating leachate, was used to reduce the average total petroleum hydrocarbon concentration in a diesel-contaminated soil from 6200 mg/kg dry soil to 280 mg/kg in approximately 7 weeks (Reynolds et al., 1994). A bed reactor with forced aeration was also used to treat 115 000 m3 of soil contaminated with bunker C fuel oil (Compeau, Mahaffey Patras, 1991) and 23 000 m3 of soil contaminated with gasoline and fuel oil (Block, Clark Bishop, 1990). 

In figure 4 measured mean bubble sizes are shown for the aeration of xylene and propanol by nitrogen. The measurements took place in a column of 225 mm diameter. The measuring height was 850 mm above the gas distributor, which was formed as a sieve tray with different hole diameters. It can be seen, that the... 

Figure 4. Sauter mean bubble diameter as a function of gas linear velocity for the aeration of xylene and propanol...

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