摘要
By means of experiments of CO_2 miscibility with crude oil,four nonpolar chemicals were evaluated in order to enhance the miscibility of CO_2with crude oil.Through pre-slug injection and joint injection of toluene in CO_2,crude oil displacement experiments in the slim-tube were conducted to investigate effects of the tolueneenhanced CO_2 flooding under simulated subterranean reservoir conditions.Experimental results showed that toluene can enhance extraction of oil into CO_2 and dissolution of CO_2 into oil with the increment of 251%and64%respectively.Addition of toluene can obviously improve the oil recovery in either pre-slug injection or joint injection,and the crude oil recovery increased with the increase of the toluene concentration.The oil recovery can increase by 22.5% in pre-slug injection with the high toluene concentration.Pre-slug injection was recommended because it can consume less toluene than joint injection.This work could be useful to development and application of the CO_2 flooding in the oil recovery as well as CO_2 emission reduction.
By means of experiments of C02 miscibility with crude oil, four nonpolar chemicals were evaluated in order to enhance the miscibility of C02 with crude oil. Through pre-slug injection and joint injection of toluene in CO2, crude oil displacement experiments in the slim-tube were conducted to investigate effects of the toluene- enhanced C02 flooding under simulated subterranean reservoir conditions. Experimental results showed that toluene can enhance extraction of oil into C02 and dissolution of C02 into oil with the increment of 251% and 64% respectively. Addition of toluene can obviously improve the oil recovery in either pre-slug injection or joint injection, and the crude oil recovery increased with the increase of the toluene concentration. The oil recov- ery can increase by 22.5% in pre-slug injection with the high toluene concentration. Pre-slug injection was recom- mended because it can consume less toluene than joint injection. This work could be useful to development and application of the CO) flooding in the oil recoverv as well as CO2 emission reduction.
基金
Supported by the National Science&Technology Pillar Program(2012BAC24B03)