Modelling and evaluation of dual reflux pressure swing adsorption cycles: Part II. Productivity and energy consumption

In this second part of our dual reflux PSA study, we have examined the power and productivity tradeoffs of all of the dual reflux cycles developed in Part I. It was found that the concentration of heavy component in the feed is the primary variable that influences the choice of dual-reflux configuration. Feed to the high-pressure bed and equalisation, pressurisation and blowdown with the strongly adsorbed component is favoured at low concentrations of heavy component in the feed gas. Feed to the low-pressure bed and equalisation, pressurisation and blowdown with weakly adsorbed component is favoured for high concentrations of heavy component in the feed gas. For highly selective adsorbents, the differences between the work-productivity tradeoff curves for the four configurations are quite distinct, becoming less distinct as the ease of separation decreases.