How do I choose optimum reflux ratio?
The total cost, which is the sum of fixed cost and operating cost, must therefore passes through a minimum. The reflux ratio at this minimum total cost is the optimum (or economical) reflux ratio. Typically the optimum reflux ratio is approximately 1.2 to 1.5 times Rmin.
What is the optimum reflux ratio in distillation?
The Optimum Reflux Ratio (R0) is that at which the total cost of the distillation is a minimum, taking into account the capital cost of the column (which depends on the number of theoretical plates) and running cost, which depends on the reflux ratio.
How does reflux ratio affect column efficiency?
The higher the reflux ratio, the more vapor/liquid contact can occur in the distillation column. So higher reflux ratios usually mean higher purity of the distillate. It also means that the collection rate for the distillate will be slower.
What is reflux ratio in distillation column?
The reflux ratio is defined as the ratio of the liquid returned to the column divided by the liquid removed as product, i.e., R = Lc/D.
Can minimum reflux ratio be less than 1?
Thank you for your answers. As far as I understand there is no limit for reflux ratio if desired specs and economically feasable operation is achieved.
How do you increase the efficiency of a distillation column?
Wrap the distillation column with an insulator like aluminum foil. The insulation will allow the vapors to travel all the way to the top of the column and out the condenser. The increase in efficiency results from the repeated interaction with the column packing.
How does reflux ratio affect number of stages?
Table 3 shows that the number of stages increases as the reflux ratio increases for both cold and saturated feed. For the cold feed the number of stages increases from 1.79 to 2.26 while 1.59 to 1.73 for the saturated feed. However the number of stages required for saturated was less compared to cold feed.
How many stages can a distillation column have?
When more ideal stages are required, the packing should be separated into sections of no more than 10 ideal stages, with vapor and liquid redistribution in between.
How do you control reflux ratio?
When the reflux ratio is large and reflux is used to control the reflux-drum level, a frequently used scheme controls the reflux ratio by measuring the reflux flow rate and rationing the distillate flow rate to the reflux flow rate.