油藏物理学英文油藏物理学 (5).ppt
Hydrocarbon Phase Behavior and Vapor-Liquid Equilibrium in Reservoirs(油气藏油气藏烃类的相的相态和汽液平衡和汽液平衡)Terminology:Phase behavior:相相态Phase diagram:相相图Bubble point：泡点：泡点Dew point：露点：露点Critical ponit：临界点界点Phase envelope：相：相包包络线Two phase region：两相区：两相区Quality lines:等液量等液量线Cricondentherm:临界凝析温度界凝析温度Cricondenbar:临界凝析界凝析压力力Locus：轨迹迹Curve：曲：曲线Shrinkage：压缩Volatile：挥发性性的的Condensate gas：凝析气：凝析气Depletion：衰竭，降：衰竭，降低低 Retrograde gas condensate:反凝析油反凝析油Separator：分离器：分离器Equilibrium ratio：平衡比平衡比TPA(equilibrium point)BCDLiquidLiquidGasGasSolidSolidVaporizationsublimationdissolveClassification of gas,liquid and solid体系体系(System)相相(Phase)组分组分(component)For a constant composition system,the relationship between pressure,temperature and volume can be represented by EOS f(Pf(P，v v，T)T)0 0 Phase diagram is the graphic display of EOS.(将状态方程以图示法表示就是相图将状态方程以图示法表示就是相图)3D phase diagram：PVT 2D diagram:P-V、PTTriangle diagram：C1-C2-6-C7+1、3D phase diagram (三维相图三维相图)2 2、2D diagram 二维相图二维相图 （or Plane phase diagram平面相图）平面相图）The P-T diagram is most convenient P-V(压力力-比容比容图)and P-T(压力力-温度温度图)phase diagram are generally used in petroleum industry.2D phase diagram of propane(丙烷的二维相图丙烷的二维相图)3、Triangle phase diagram 三角相图三角相图 3.1 The characteristics of phase behavior1、Key parameters(1)Bubble point pressure(泡点压力):refers to pressure at which the first bubble occurs under constant temperature when pressure decreases(2)Dew point pressure(露点压力)：refers to pressure at which the first liquid dew occurs under constant temperature when pressure increases 3.1.1 The characteristic of single component system 单组分体系的相分体系的相态特征特征 (3)Saturated vapor pressure curve(饱和蒸汽压线)：refers to the line showing that vapor and liquid phase coexist for single component system(4)Critical point(临界点)：refers to the end of saturated vapor pressure curve(point C).(5)Critical temperature(Tc)，critical pressure(Pc)：refers to the corresponding temperature and pressure at the critical point(30C,4.88MPa)(30C,4.88MPa)2、P-T diagram for ethane 3、P-T diagram for different pure system (1)Bubble point curve(泡点线):is defined as the line separating the liquid phase region from the two phase region(2)Dew point curve(露点线):is defined as the line separating the vapor phase region from the two phase region(3)Cricondentherm(临界凝析温度):is defined as the maximum temperature above which liquid can not be formed regardless of pressure.(4)Cricondenbar(临界凝析压力):is defined as the maximum pressure above which no gas can be formed regardless of temperature.3.1.2 The characteristic of binary component system 双双组分体系的相分体系的相态特征特征 1、Key parameters (5)Phase envelope(相包络线):the region enclosed by the bubble-point curve and the dew-point curve,wherein gas and liquid coexist in equilibrium,is defined as the phase envelope of the hydrocarbon system.(6)Quality lines(等液量线):refers to the dash lines within the phase diagram.They describe the pressure and temperature conditions for equal volumes of liquids.cricondenbarcricondentherm2、P-T diagram for binary system3、Typical P-T diagram for a binary system 1)The two-phase region is between the saturated vapor line of individual pure substance.2)The Pc is higher than one of pure substance,while Tc is between that of both pure substance.3)Point C will migrate to the side closer to the heavy substance with the content increase of heavy one,accompanied with the P-T drifting to the saturated vapor pressure curve of heavy substance 4)The two phase region is larger if the proportion of both component is close,contrary to the bigger proportion
