NATURAL GAS LIQUIDS RECOVERY
Universal Vortex Inc. (UVI) offers VORTEX, a proprietary refrigerating technology to enhance NGL (natural gas liquids) recovery from natural gas at plants utilizing Joule-Thomson (JT) effect to reduce gas temperature.
The VORTEX requires the same equipment/layout as the standard JT plant. To change from JT based process to VORTEX one need only replace the Joule-Thomson Valve (JTV) with the Vortex Tube (VT) of UVI design. The VT is set to operate at the same inlet/outlet pressure as JTV.
The VORTEX operation includes the following features:
- Gas expansion in the VT’s inlet nozzles where gas temperature drops due to the Joule-Thomson effect
- Temperature division of the expanded flow in the VT that results in creation of the vortex ‘cold’ and the vortex ‘hot’ fractions (Vortex Effect)
- Removal of the ‘hot’ fraction’s energy from the process
- Rejoining an original ‘cold’ fraction and now chilled ‘hot’ fraction in the single super cooled stream and
- Separation of the condensed NGL
Although the Vortex phenomenon has been known for decades, only Universal Vortex has designed and tested units suitable for applications in natural gas processing. The proprietary Vortex Tube, the heart of the VORTEX, can operate with moist, or even two-phase inlet flow, and create up to a 200ºF temperature division between ‘cold’ and ‘hot’ fractions, thus providing for the efficient ‘hot’ fraction’s heat dissipation.
In the Vortex Tube the Joule-Thomson cooling and the Vortex cooling combine, therefore under equal conditions the gas temperature in the VORTEX will be always lower than that in the JTV, thus securing a deeper Natural Gas Liquids recovery. Alternatively, the same liquids recovery can typically be obtained with reduced expansion ratios, thereby offering the opportunity for reduced compression cost.
The VORTEX advantage over the typical JT valve recovery depends on the feed gas composition and gas inlet and outlet pressures. As an example, for a relatively heavy gas (Methane-69 Mole%) with 990-psia inlet pressure and 420-psia discharge the VORTEX demonstrated up to 15% increase in ethane condensation and some 5-10% increase in propane recovery (based on HYSIM™simulation calculations).
The Vortex Tube used in the VORTEX applications is a device with no moving parts, compact and space saving.
For example, the Vortex Tube designed to operate at 990 psi inlet pressure for a 10 MMSCFD gas processing plant is approximately 3’’ in diameter.
Universal Vortex provides for process simulation, calculates and designs VORTEX and supplies Vortex Tube(s) customized for each application. The VORTEX can be designed to handle a variable flow rate.
The principal benefits of VORTEX are:
- Substantial increase in hydrocarbons recovery as compared with the JT process
- Low capital and operating cost
- No moving parts. Compact design
- Easy to install or retrofit in the existing JT plant
- Can be used for Dew Point Control in gas gathering systems
- Requires less booster compression to operate with the JTV efficiency
- Can be scaled down and utilized in smaller applications such as booster compressor’s fuel gas conditioning etc.