AIR-STRIPPER DESIGN AND COSTING COMPUTER-PROGRAM

Packed-tower, countercurrent air-stripping is widely used to remove vo latile organic compounds from contaminated water. An air stripper is d esigned using a well-developed mathematical model of the process. Howe ver, the number of variables in the model exceeds the number of constr aining equations by two, with the result that a number of alternative air-stripper designs are possible for a particular water treatment obj ective. To select one or several designs associated with minimum capit al and operating costs, it is necessary to develop a large number of p ossible designs and to estimate the costs associated with each. The ai r-stripper design and costing (ASDC) program, a microcomputer-based pu blic-domain program, automates the iterative design and cost calculati ons and thus enables rapid, preliminary evaluation of alternative air- stripper designs and associated costs. In this article, the design met hodology and cost-estimation techniques incorporated in ASDC are descr ibed, and ASDC cost predictions are compared with costs reported for a ctual operating air strippers.