The reaction is EO + water → EG.

The column is fed with a mixture of water and EO at stage 2 (a small excess of water is used). The reactive section is composed of only stage 1. The column has five stages, a partial reboiler, and a partial condenser (with a reflux stream and one vapor stream leaving this section).

For low Damköhler numbers (with molar hold-up of zero), EG is not formed and the only species present in the column are water and EO.

At high Damköhler numbers, we get almost pure EG as a bottom and pure water as a top vapor stream. The reflux and reboil ratios are taken equal to 1000 and 40. Thus, the vapor stream leaving the top section of the RD column has a very small flow rate.