Mechanical Refrigeration Units

ETI provides treatment systems to process and remove heavy hydrocarbons and water from natural gases. The process equipment consists of standalone vessels and skid-mounted modules. A MRU consists of two operations: a cold separator and a refrigeration system. A regeneration system may be employed to minimize solvent costs.


Fuel Gas Conditioning JT Skid for Hydrocarbon Dew Point Control installed in Colombia, South America.


The components of a mechanical refrigeration plant are: inlet separator or filter separator, exchangers, chiller and refrigeration system (compressor, condenser/air cooler, receiver, and instruments, controls, and accessories) and glycol/methanol injection. The refrigeration systems most commonly used are propane or ammonia systems, although non-CFC Freons are also used.

Reasons for MRU Treatment
Gas engines for compression or pumping require a high quality fuel gas. Fuel gases must be conditioned to lower the heating value of the gas by removing the majority of the heavy hydrocarbon components, butane and heavier nC4+. A mechanical refrigeration system is quite similar in process scope to the Joule-Thompson auto-refrigeration fuel gas treating units. The process gas stream is injected with a hydrate inhibitor such as methanol or ethylene glycol. The process gas temperature is lowered to between 0°F and -40°F. Heat exchangers conserve chilling requirements. The recovered hydrocarbon liquid is either combined with other production liquids or stabilized as LPG. To reject absorbed water, a regeneration package consisting of heat exchangers, a flash separator, particulate filter, charcoal filter, electric- or gas-fired heated glycol reboiler, glycol stripper, reflux tower, and injection pumps is utilized. A typical MRU will lower the HHV of the fuel gas to 1050 Btu/scf or less, the Methane Number, MN >65, and the butane number, NBN<4.5.



  • Skid-Mounted Modules
  • Economical Operation
  • Efficient Operation
  • Closed System
  • Unattended Operation
  • Regeneration of Meg
  • Stainless Steel Valve Trays
  • Meg Circulation Rates From a Few  to Several Gpm Flow
  • Stainless Steel Meg Stripping Column Option
  • Venting, Incinerating Off Gases
  • Doesn’t Require Compression of Gas Stream
  • Compact Modules
  • Minimal Hydrate Inhibitor Inventory
  • Low Hydrate Inhibitor Makeup
  • Up and Down Stream Filter/Coalescing
  • Heat Stable Salts
  • Local or Remote Control Options
  • Rectification of Stripped Glycol