Transient Natural Gas Liquefaction Process Comparison- Dynamic Heat Exchanger Under Transient Changes in Flow for Energy Storage with Cryogenic Carbon Capture (CCC-ES)

Transient modeling and optimization of two natural gas liquefaction processes have been done using Aspen HYSYS. In case of energy consumption, the optimized model has been chosen for transient modeling. These results pertain to Liquified Natural Gas (LNG) generally and to an energy storage process associated with cryogenic carbon capture (CCC) in which the LNG process plays a prominent role. The energy storage CCC process influences the time constants and magnitudes of the flow rate characteristics. These flowrate variations affect all units, especially compressors and heat exchangers. New types of heat exchanger design and optimization method; Model predicted control theory (MPCT) have been presented and transient responses have been compared with traditional design. The proposed process controls temperatures, pressures and other operating parameters. K-value- and U-value-techniques guide flowrate and heat exchanger stream variations. Transient responses to both ramping and step-changes in flow rates indicate process responses, including summary effects represented in transient efficiency graphs.Finally natural gas (NG) consumption and LNG  production have been compared to show the optimality of new design.