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Gas fractionation

Natural and petroleum associated gases are processed by the method of low-temperature gas separation. The source of cold is, as a rule, a turbo-expander unit.

  Plant capacity in terms of source gas   0.5–3.0 bln. cub.nm/year
  Mini-plant capacity   6–50 thou. cub.nm/hour
  Recovery factor of light component   up to 0.98

Depending on the source gas composition, the following target products can be produced:

  • combustible natural gas (according to GOST 5542-87, 27577-87)
  • ethane fraction (TU 0272-022-00151638-99)
  • propane-butane mixture, technical grade (GOST 20448-90)
  • propane and propane-butane, automobile grade (GOST 27578-87)
  • LPG (liquefied petroleum gases)
  • natural gasoline, stable (TU 39-1340-89)
  • isobutane (TU 38.101 497-79)
  • normal butane (TU 38.101 492-79)
  • isopentane (TU 38.101494-79)
  • normal pentane (TU 38.101 493-79)
  • pentane-hexane fraction

A standard processing plant for natural gas and petroleum associated gas comprises the following units:

  • Source gas preparation unit – designed for additional compressing of gas (at low pressure), drying from moisture and purification from solids and other impurities
  • Cooling unit – for cooling and partial condensation of source gas and recovery of heavy components
  • Demethanizing unit – for separation of stripped gas used for local needs or returned to the main gas pipeline
  • Gas fractionating unit – for production of required target products
  • Heat-transfer fluid unit – for heating bottom product of columns
  • Compressor unit – for additional compressing of stripped gas up to pressure of main gas pipeline
  • Furnace unit – for heating adsorber regeneration gas
  • Final products storage facility

Monitoring and control over the plant are provided by an automated control system.

LENNIIHIMMASH Group has patent RU 2225971 "A method for petroleum associated gas separation" for the method of petroleum associated gas separation comprising preliminary separation of source mixture, adsorption drying, successive cooling in heat exchangers, etc. The patent effective date is March 3, 2003.