Twister Supersonic Separator is an innovative and revolutionary gas processing system. The Twister technology was developed by Shell. Twister B.V. was launched as a separate company in April 2000 by Shell Technology Investments Partnership, a 50/50 venture between Shell and the Beacon Group. Twister Supersonic Separator is the resulting synergy from combining aero-dynamics with the traditional gas processing concepts of thermodynamics and fluid dynamics. Twister is based on the following concepts (Figure 1):Gas is expanded in a Laval nozzle to supersonic velocities with resulting lower temperatures.Nucleation of water and hydrocarbon occur, followed by growth of liquid droplets.The gas and liquid droplets enter the wing section, where a very high swirl is created and the liquid droplets are centrifuged onto the walls, creating a liquid film.The gas and liquids are separated in the drainage section.Pressure is recovered in the diffuser section, to about 70– 80% of the initial pressure. This is done without chemicals or rotating equipment, and requiring minimum space and weight, thus saving significant capital and operating costs. Figure 2 shows the phase envelope of a natural gas and the water concentration curve. Twister is compared with the Joule-Thompson Valve and the Turbo- Expander. In this example all three processes have the same outlet pressure (sales pressure), which is typical for most applications. Joule-Thompson is an adiabatic process and the least efficient. Turbo-expander is near 85% isentropic efficiency, so it goes deeper into the phase envelope and uses its re-compressor to reach the outlet pressure. However, Twister has about 90% isentropic efficiency, so it goes the deepest into the phase envelope, then recompresses without rotating equipment to the outlet pressure. Twister is effectively a turboexpander/ separator/re-compressor all in one static piece of equipment. Thus, from a theoretical point of view, Twister has the most favorable thermodynamics. The challenge is to translate this theoretical advantage into the operations of actual gas plants.

Twister Supersonic Separator is an innovative and revolutionary gas processing system. The Twister technology was developed by Shell. Twister B.V. was launched as a separate company in April 2000 by Shell Technology Investments Partnership, a 50/50 venture between Shell and the Beacon Group. Twister Supersonic Separator is the resulting synergy from combining aero-dynamics with the traditional gas processing concepts of thermodynamics and fluid dynamics. Twister is based on the following concepts ( Figure 1): -Gas is expanded in a Laval nozzle to supersonic velocities with resulting lower temperatures. -Nucleation of water and hydrocarbon occur, followed by growth of liquid droplets. -The gas and liquid droplets enter the wing section, where a very high swirl is created and the liquid droplets are centrifuged onto the walls, creating a liquid film. -The gas and liquids are separated in the drainage section. -Pressure is recovered in the diffuser section, to about 70-80% of the initial pressure.minimum space and weight, thus saving significant capital and operating costs. Figure 2 shows the phase envelope of a natural gas and the water concentration curve. Twister is compared with the Joule-Thompson Valve and the Turbo-Expander. In this example all three processes have the same outlet pressure (sales pressure), which is typical for most applications. Joule-Thompson is an adiabatic process and the least efficient. Turbo-expander is near 85% isentropic efficiency, so it goes deeper into the phase envelope and uses its re-compressor to reach the outlet pressure. However, Twister has about 90% isentropic efficiency, so it goes the deepest into the phase envelope, then recompresses without rotating equipment to the outlet pressure. Twister is effectively a turboexpander/separator/re-compressor all in one static piece of equipment.Thus, from a theoretical point of view, Twister has the most favorable thermodynamics. The challenge is to translate this theoretical advantage into the operations of actual gas plants.There are many potential Twister applications (dehydration, dew pointing, C5+, LPG, C2, LNG, CO 2 /H 2 S, etc.), so it is important to focus our technical resources in a limited number of development areas. On this basis, SPE 87262