Studies Gas Channeling Nature Of The Foam

Foam is used to solve the problem of gas channeling in gas driving,, and was practiced in the reservoir, and has achieved certain results. Bur the study for the gas channeling definition of foam and related conditions about screening at home and abroad have seldom been reported in the literature.Gas channeling capacity of foam and the stability of the foam in porous media inr reservoir conditions are equivalent. so this paper use Warning blender method to do the screening study of the foam system. New non-ionic surfactantthe agent QW19has been screened to meet the requirements of. high temperature and high salinity reservoirs.Its long-term stability in the thermohaline conditions has been determined..Experimental study is carried out for cores of different permeability in different conditions to evaluate anti-gas channeling ability of foam.. Gas channeling ability and influencing factors of foam QW19are verified.In the experiment of temperature60℃, back pressure6MPa and air injection conditions, a large number of core-flow experiments have been carried out with statistical analysis. studied Different parameters on the anti-gas channeling ability of foam have been studied to explore anti-gas channeling mechanism of foam.The parameters includes: gas-liquid ratio, mass fraction of blowing agent, the injection method, permeability, temperature, pressure and number of injection PV. And thereby the range of the core permeability with QW19foam system of the mass fraction of0.2%is defined in certain conditions, and the size of the gas-liquid ratio and the interval range of the number of PV in foam injection have been optimized。So a theoretical guidance about gas anti-channeling ability of QW19foam system which is in formation conditions is provided.In addition, in order to study the sealing capacity of QW19foam system in the hypertonic heterogeneous reservoir, the study found that the foam which is added with polymer LR78of mass fraction0.1%and, resistance factor of the core with greater permeability is increased by10times, whereby the foam can block high permeability layers and improve sweep efficiency of the low-permeability layer.Finally, by a large number of core gas channeling experiments, parameters about QW19foam system of the mass fraction0.2%has been defined:(1) value of resistance factor in the experimental program sort in six different gas-liquid ratio:1:2＜1:1＜5:1＜4:1＜3:1＜2:1. The gas-liquid ratio range of QW19blowing agent is optimized between1:1to3:1. the optimal gas-liquid ratio of the blowing agent QW19is2:1within the experimental research.(2)The interval of permeability for QW19blowing agent of concentration0.2%is defined as [0.95×10-3μum2,1312.34×10-3μm2].The results show that Purports foam can play the role of gas channeling, this also shows that screened the dynamic stability of the foam system in porous media better gas channeling. In addition, QW19blowing agent can generate foam, reduce gas flow and seal gas channeling and improve sweep efficiency of gas driving in the reservoir formation whose reservoir permeability is less than1312.34×10-3μm2. This study not only enriches the theory and experimental basis for anti-gas channeling of foam system, but also has a certain reference value to the practice, but also provides a basis for further exploration of different reservoir with gas EOR adaptability.