A hybrid technology combining heat pump and thermally coupled distillation sequence for retrofit and debottlenecking

Increasing the capacity of an existing distillation process has been a major focus of the chemical process industry. On the other hand, entrainment flooding can occur as a result, which can create a bottleneck in the distillation process. This paper reports the results of a techno-economic feasibility study to debottleneck the distillation column using a proposed hybrid process combining a heat pump and thermally coupled distillation sequence. Fractional utilization of the area was used to identify flooding problems in the column as well as how much area is available for vapor flow on an existing stage. A heat pump aided thermally coupled distillation sequence (HPTCDS) was designed and optimized using a response surface methodology. Two cases were examined to test the proposed sequence. The results showed that the proposed sequence can achieve significant energy savings and remove the bottleneck problem.