Low Temperature Process Design (2019)

Low temperature gas processing and liquefaction is a major subject in natural gas processing. It enables the production of natural gas to specification for fuel or chemicals feedstock, extracts valuable components for sale and is used to produce liquefied natural gas (LNG) on which many countries depend for clean energy.

Low temperature processes need cost-effective production of refrigeration and can be very large power consumers, especially for liquefaction. Cost-effective processing relies on understanding the relation between energy and power (or work) and process integration techniques for energy efficiency and optimisation.

Both cryogenic nitrogen removal from natural gas and natural gas liquids extraction need efficient distillation and present challenges in optimising separation processes and energy transfer.

Optimal process design will be discussed by examining some fundamental thermodynamic principles and related process evaluation techniques (especially for multicomponent distillation). These help to screen and select low-cost designs prior to detailed process simulation. Industrial examples will be shown to demonstrate key equipment such as turbo- expanders and plate-fin heat exchangers.