Optimal control of reflux ratio for batch distillation

To obtain maximum production under minimum utility-cost,the optimal operation of reflux ratio is considered for a batch distillation process, Pontryagin's maximum principle is one of the solutions to calculate such an optimal operation, but it requires extenstive trial and error. In this paper, a faster algorithm is proposed to modify the initial values of Hamilton's multiplier. With the rapid growth of computer power, this algorithm will provide a way to realize the real-time optimization and control of the reflux ratio. To reduce the on-line calculation, a control table for the optimal operation can be calculated off-line as a function of State variables. These control methods provide the real optimal operation for a given evaluation function.