(34b) Optimum Pumparound Balance Between Energy & Fractionation Efficiency

In a petroleum refinery, multi-product fractionators, including crude atmospheric columns, crude vacuum columns, FCC main fractionators and coker main fractionators are core pieces of equipment. Most of multi-product fractionators are equipped with multiple pumparound circuits for an inter-condenser system. Compared to the pumpback method, the pumparound method achieves more uniform vapor/liquid traffic through the column. Multiple pumparound circuit locations and balances influence not only the unit heat balance but also column fractionation efficiency. Inappropriate pumparound system design can cause capacity limitation, low energy or downgraded fractionation efficiency.

This paper will discuss critical issues for optimum pumparound design between energy and fractionation efficiency requirements. The case studies will demonstrate how pumparound circuit design is modified for optimum energy and fractionation efficiencies.