Heat integration of fractionators for low temperature separation unit (LTSU) and product recovery unit (PRU)

摘要

Chemical processing plant typically consumes a lot of energy that used to convert raw materials to desired products. Having said that, gas processing plant (GPP) also requires intensive energy to fractionate mixture of hydrocarbons into sellable products such as sales gas, ethane, propane, butane and so on. In order to reduce the operating cost, energy recovery through Pinch Analysis need to be carried out that utilize hot and cold streams of Low Temperature Separation Unit (LTSU) and Product Recovery Unit (PRU) in GPP. In this research, typical Process Flow Diagram (PFD) of LTSU and PRU has been modeled using Aspen Hysys V7.0. Existing energy consumption provides a basis for better process improvement. Therefore, both of Composite Curve and Problem Table Algorithm were used for targeting energy that can be recovered within the process It shows that the values of QHmin and QCmin are 539 kW and 4644 kW respectively and the energy that can be recovered is 2854 M.As well as to determine QHmjn and Qmin. To realize these recoveries, conceptual design of heat exchanger network (HEN) has been presented. The economic trade-off between energy saving and capital investment for heat exchangers should be determined for future considerations.