When reflux ratio to the column is minimum and zero, what are the requirements in column

When reflux ratio is minimum, column requires maximum number of trays and minimum reboiler load for a required separation. To avoid this problem of infinite trays we use optimum reflux ratio.

When reflux ratio is zero, column requires infinite number of trays and minimum reboiler load for a required separation. To avoid this problem of infinite trays we use optimum reflux ratio.