BATCH STUDIES ON A CLOSED-LOOP AIR STRIPPING PROCESS

Ultraviolet photooxidation is an effective process for the destruction of organics in air. In this paper we examine the use of u.v. photooxidation to treat the exhaust air from a stripper. VOC contaminated water was air stripped using a hollow fiber membrane module and the VOC laden air was u.v. photooxidized and recycled to the stripper in a closed loop. Batch experiments were conducted under different operating conditions. A mathematical model was developed for the process and model predictions of process performance compared favorably with the experimental results. The closed loop air stripping process (CLASP) offers a number of potential advantages over conventional air stripping with off-gas treatment: no VOCs are released to the atmosphere; the VOCs are oxidized to harmless end-products; no adsorber is required; and no adsorbent regeneration or disposal costs are incurred.