low-temperature separation

The low-temperature separation (LTS) process is widely used for moisture and condensate removal in natural gas treatment and is typically controlled using local automation systems. However, the process is inherently multivariable, with strong cross-couplings between inputs and outputs, and is significantly affected by external disturbances. This study defines the control inputs as actuator signals on the gas and condensate outlet lines, while the outputs are the gas pressure and condensate level in the separator.

The gas produced from the well under high pressure is fed to a complex preparation unit, where solid impurities and water are removed. Purified natural gas contains valuable components such as condensate, as well as heavy hydrocarbons, butane and propane. To extract associated components from gas (condensate and heavy hydrocarbons) low-temperature separation is used. The temperature regime in the separator is maintained by the energy of the compressed gas. When the gas passes through the throttle, due to the Joule-Thomson effect, the pressure and temperature decrease.