Minimum Reflux Design Using TTs

FIGURE 5 A feasible design at minimum reflux for ot=[5 2] using TTs. 

Try this for yourself using DODS-SiCo and the TT design option, design minimum reflux simple columns, trying various a values, and product qrecifications. 

Apart from being limited to sharp splits, the TT design method cannot be applied to nonideal systems since the boundaries between pinch points are not precisely linear and therefore there is no basis for a colinearity condition. 

FIGURE SJ26 Infeasible design for nonsharp product specihcations using TTs. 

Consider now point A, one of the pinch points in the rectifying section. Since this point corresponds to a compositional steady state, it must satisfy the condition where dxidn = 0. Thus, we can write for point A in a vectorized form  

---