A continuous distillation column is used to produce a 65% ABV rum as distillate product from an 8% ABV wash. Reflux is established through a dephlegmator/partial condenser. Energy is saved by using the wash as the cooling fluid in the partial condenser. The wash is supplied at 100 kmol/h at an initial temperature of 20 C, and leaves the partial condenser at 80 C. The pre-heated wash is then heated further up to its bubble point using steam, before being fed into the column. The bottom product contains 0.2 mol% ethanol (0.65% ABV). Demonstrate that the reflux ratio is 1.72.