Experimental Investigation of Enhanced Oil Recovery by Thermal Foam Flooding

Abstract

Foam has been widely used in petroleum industry. It could enhance oil recovery by the means of improving mobility ratio, selective plugging and lowering the interfacial tension(IFT) of oil and water. The influences of concentration, temperature, gas-liquid ratio, permeability and oil saturation on the plugging property of 3 foaming agents were studied experimentally. The foaming agent concentration and the ratio of steam to nitrogen for thermal foam flooding were optimized. Displacement experiments were performed to investigate the EOR effect of 2# foaming agent. It was shown that the resistance factor increased with the increase of the concentration, gas-liquid ratio and permeability and the increase velocity slowed down in the later period of experiments. The optimal concentration was 0.5wt% and the optimum gas-liquid ratio was 1:1. The resistance factor reduced with increasing oil saturation. The plugging ability lost when the oil saturation was greater than 0.2. The resistance factors of 1# and 2# foaming agents decreased with increasing temperature but 3# increased. The best concentration was 0.6wt% and the ratio of steam to nitrogen was 3:2 for steam and nitrogen foam flooding. In the process of thermal foam flooding, oil recovery increased by 20.82%, and the sweep efficiency and displacement efficiency was 13% and 24.6% , separately.

Experimental Research and Quantitative Characterization of Nitrogen Foam Blocking Characteristics

“…With the development of chemical processes, in recent years some new foaming agents appear, and their blocking ability increases with the increasing temperature. 39 Although this kind of foaming agent only has the tendency that resistance factor increases with temperature increasing, the resistance factor in high temperature is still very low. Hence, the study on high temperature resistance and high blocking ability foaming agent is important in surfactant development area, which is significant for the application of foam flooding in high temperature reservoirs and thermal foam flooding technology.…”

“…However, as the foam system widely used in oilfield development, it has been used to develop high temperature reservoirs and thermal recovery process, in which the environment temperature is high, and the blocking ability decreases. With the development of chemical processes, in recent years some new foaming agents appear, and their blocking ability increases with the increasing temperature . Although this kind of foaming agent only has the tendency that resistance factor increases with temperature increasing, the resistance factor in high temperature is still very low.…”

“…The foaming volume is defined as the maximum foam volume of a certain volume of foaming agent solution (100 mL of predetermined concentration by weight) at a fixed shear velocity for 5 min. The half-life is defined as the time taken by the foaming volume to decrease to its half size. , The adjustment capability of gas phase mobility in porous media is affected by both foaming ability and foam stability. To evaluate the static characteristic of foaming agent thoroughly, average foam composite index ( S ) is used to consider the influences of maximum foaming volume and half-life simultaneously.…”

Experimental Investigation on the Effectiveness of 1-Butyl-3-methylimidazolium Perchlorate Ionic Liquid as a Reducing Agent for Heavy Oil Upgrading

“…4,5 Various methods have been used to upgrade and reduce the viscosity of the oil in recovery of heavy oil including thermal and nonthermal methods. Thermal methods such as steam flooding, 6 aquathermolysis, 7 and steam-assisted gravity drainage 8 give high recovery factors compared to nonthermal methods. However, thermal methods have several disadvantages as they require high temperature, have a high cost for production and regeneration, and produce undesired impacts to the environment.…”