Extraction of С3+ hydrocarbons from a gas-condensate mixture during the field treatment of a bedded fluid
The article studies efficacy of С3-С4 and С5+ hydrocarbons recovery from gas-condensate fields rich in С5+ hydrocarbons using the low-temperature separators. At the temperature level of -30°С the extent of С3-С4 hydrocarbons comes up to ~50% and is nearly constant during the period of field development. But the extent of С5+ recovery gradually decreases from 97-98 to 92% due to dropout of retrograde condensate. Residual of С5+ hydrocarbons in the separator gas for different gas-condensate fields with condensate factor of 150-200 g/m3 varies from 2,0 to 6,0 g/m3 and insignificantly changes during all the period of field exploiting. An issue of optioning a selective hydrocarbon absorbent in order to increase the extent of С3- С4 and/or С5+ hydrocarbon recovery in comparison to the technique of field low-temperature absorption is studied. Calculations showed that application of low-temperature (from -30 to -25°С) absorption for field gas treatment at gas-condensate fields allows additional recovery of ~30% for С3-С4 hydrocarbons and 25-30% for С5+ hydrocarbons.