西安石油大学：《油藏物理（油层物理学）Petro-physics》精品课程教学资源（英文课件）Fluid 2.3 physics property of nature gas 天然气的高压物性

physics property of nature gas at high pressure Xuanqi zhang Petroleum engineering college

physics property of nature gas at high pressure Xuanqi zhang Petroleum engineering college

油藏物理学一天然气的高压物桂 1 basic concept of natural gas composition:Natural gas is a mixture of low molecular weight alkane and a small amount of non- hydrocarbon gas. ●Weight composition G M:% ∑M, ●volume composition V= ∑V moore composition N% ∑N, MV N;is respectively molecular weight, volume and mole fraction of component i

油藏物理学——天然气的高压物性 1 basic concept of natural gas composition： Natural gas is a mixture of low molecular weight alkane and a small amount of non￾hydrocarbon gas. ● Weight composition %   i i i M M G ● volume composition %   i i i V V V ● moore composition %   i i i N N Y Mi、Vi、Ni is respectively molecular weight, volume and mole fraction of component i

油藏物理学一天然气的高压物桂 2 classification on natural gas by reservoir:gas of gas reservoir,gas of oil reservoir,gas of gas condensate reservoir and gas of coal bed by component:wet gas and dry gas by sulfur:acid gas (>1g/m3s )and net gas (<1gm3s)

油藏物理学——天然气的高压物性 2 classification on natural gas ● by sulfur：acid gas (>1g/m3 s ) and net gas (<1g/m3 s ) ● by reservoir：gas of gas reservoir, gas of oil reservoir, gas of gas condensate reservoir and gas of coal bed. ● by component: wet gas and dry gas

油藏物理学一天然气的高压物桂 3 molecular weight of natural gas Molecular weight of natural gas equal to a molar mass of natural gas in standard conditions.That is, M=∑Y,M,) Ma≈29(28.96) i=l Y;、M;一mole fraction and molecular weight of component i

油藏物理学——天然气的高压物性 3 molecular weight of natural gas Molecular weight of natural gas equal to a molar mass of natural gas in standard conditions. That is,   n i M Yi Mi 1 ( ) Mair  29（28.96） Yi、Mi — mole fraction and molecular weight of component i

油藏物理学一天然气的高压物桂 4 relative density Gas density:g=m /v Where /cm2 or Kg/m3; m一gor Kg; V一cm3orm3

油藏物理学——天然气的高压物性 4 relative density Gas density：ρg= m /ν Where ρ g— g/cm2 or Kg/m3； m — g or Kg； V — cm3 or m3

油藏物理学一天然气的高压物桂 relative density:Y=Pg/Pa The relative density is the density of nature gas over the density of dry air in standard conditions(293K and 0.101MPa). We can approximatively express the equation. y≈M/29 y∈[0.50.7]

油藏物理学——天然气的高压物性 relative density：γ =ρg / ρa The relative density is the density of nature gas over the density of dry air in standard conditions(293K and 0.101MPa).   M / 29  [0.5～0.7] We can approximatively express the equation

油藏物理学一天然气的高压物桂 state equation of nature gas fP、V、T)=0 state equation of fluid PV=nRT for ideal gas/perfect gas PV-ZnRT for real gas

油藏物理学——天然气的高压物性 state equation of nature gas f(P、V、T)=0 state equation of fluid PV=nRT for ideal gas /perfect gas PV=ZnRT for real gas

油藏物理学一天然气的高压物桂 Where Z-deviation factor Physical meaning---deviation factor is the volume of real gas over the volume of ideal gas in real pressure and temperature. This factor accounts for the difference between the actual and ideal gas volumes

油藏物理学——天然气的高压物性 Where Z — deviation factor Physical meaning---deviation factor is the volume of real gas over the volume of ideal gas in real pressure and temperature. This factor accounts for the difference between the actual and ideal gas volumes

油藏物理学一天然气的高压物桂 Z=( Z1,VV,real gas is difficulty compressed than ideal gas

油藏物理学——天然气的高压物性 p T i a V V Z .  ( ) Z1，Va>Vi，real gas is difficulty compressed than ideal gas

Z depends on gas property,pressure and temperature,and get it by Lab Z of nature gas can be found by principle of corresponding state

Z depends on gas property, pressure and temperature, and get it by Lab. Z of nature gas can be found by principle of corresponding state