Dynamic degrees of freedom for tighter bottleneck control

To realize maximum throughput, tight control of the bottleneck unit(s) is necessary. Dynamic degrees of freedom can be used to obtain tighter bottleneck control. Here, “dynamic” means that the degree of freedom has no steady-state effect on plant operation, like most inventories (levels). Nevertheless, temporary changes of inventories can allow for dynamic changes in the flow through the bottleneck that keeps the process closer to its bottleneck constraint and increase the throughput.