A study on improvement in device performance of a double-pass concentric circular mass exchanger with uniform wall fluxes and external refluxes was conducted under counterflow operations. The linear superposition of an asymptotic
solution and a homogeneous solution with the use of an orthogonal expansion
technique for solving such a conjugated Graetz problem is formulated theoretically and the analytical predictions are applied to investigate a substantial masstransfer improvement. A mathematical expression for the average Sherwood
numbers and the outlet dimensionless concentration is given. Comparisons of analytical results are made with the single-pass operations of the same working dimensions (without permeable barriers inserted and without recycle). Considerable device improvement in mass transfer rate is obtained by introducing the recycle-effect concept in designing such double-pass devices. The effect of permeable barriers on the mass-transfer efficiency improvement as well as on the power consumption increment has also been delineated.
Chemical Engineering & Technology 31(11), pp.1638-1644