Many reactions, extractions, separations and other operations in the chemical process industries (CPI) involve the use of organic solvents. In addition to handling and disposal issues, organic solvents can pose a number of environmental concerns, such as atmospheric and land toxicity. In many cases, conventional organic solvents are regulated as volatile organic compounds (VOCs). In addition, certain organic solvents are under restriction due to their ozone-layer-depletion potential. Supercritical carbon dioxide is an attractive alternative in place of traditional organic solvents.

Besides the capital costs of a filter, there are additional factors that affect overall filtration economics, namely: (a) design considerations and options, (b) process requirements, (c) maintenance requirements, (d) maintenance procedures, (e) mean-time-between-changeout (MTBC) costs, and (f) disposal costs. This article outlines basic design issues, discusses selection considerations, and presents a cradle-to-grave cost analysis of bag and cartridge filtration.