天然气及其组分的物理化学性质

天然气及其组分的物理化学性质

自然 气的主要成分为甲烷，此外还含有乙烷、丙烷、丁烷等烃类气体，氮、CO2、H2S及微量氢、氦、氩等非烃类气体，一般气藏自然 气的甲烷含量在90%以上。油田伴生气中甲烷含量占65%～80%，此外还含有相当数量的乙烷、丙烷、丁烷等烃类气体。一、自然 气主要组分的物理化学性质自然 气主要组分的物理化学性质见表1-3-1。表1-3-1自然 气主要组分在标准状态下的物理化学性质

名称分子式相对分子质量摩尔体积Vm/(m3/kmol)气体常数R(J/kg·K)密度ρ/(kg/m3)临界温度Tc/K临界压力Pc/MPa高热值Hh/(MJ/m3)高热值Hh/(MJ/kg)低热值H1/(MJ/m3)甲烷CH416.04322.362518.750.7174190.584.54439.842

35.906乙烷C2H630.0722.187276.641.3553305.424.81670.35155.36764.397丙烷C3H844.09721.936188.652.0102369.824.194101.26651.90893.240正丁烷n-C4H1058.12421.504143.1302.703425.183.747133.88650.376123.649异丁烷i-C4H1058.12421.598143.132.6912408.143.600133.04849.532122.853正戊烷C15H1272.15120.891115.273.453746.9653.325169.37749.438156.733氢H22.01622.427412.67O.089833.251.28012.74549.04210.786氧O231.99922.392259.971.4289154.334.971—141.926—氮N223.01322.403296.951.2507125.973.349—

—氦He3.01622.42281.170.13453.350.118—

—二氧化磺CO244.01022.26189.041.9768304.257.290———硫化氢H2S34.07622.18244.171.5392373.558.89025.364

23.383空气

28.06622.40287.241.2931132.43.725—16.488—水蒸气H2O18.01521.629461.760.8330647.0021.830—

名称低热值H1/(MJ/kg)爆炸极限(体积分数)/%动力黏度μ×106/(Pa·s)运动黏度υ×106/(m2/s)沸点/℃定压比热容Cp/(kJ/m3·K)绝热指数K导热系数λ/[W/(m·K)]偏心因子上限下限甲烷

5.015.010.6014.50-161.491.5451.3090.030240.0104乙烷50.052.913.08.776.41-88.002.2441.1980.018610.0986丙烷47.5152.19.57.653.81-42.052.9601.1610.015120.1524正丁烷46.3831.58.56.972.53-0.053.7101.1440.013490.2010异丁烷45.7451.88.5

-11.72—1.144—0.1848正戊烷45.651.48.36.481.8536.06—1.121—0.2539氢45.3814.075.98.5293.00-252.751.2981.4070.21630氧120.111——19.8613.60-182.981.3151.4000.02500.0213氮

——17.0013.30-195.781.3021.4020.024890.04氦

————-269.95—1.640——二氧化碳———14.307.09-78.200.6201.3040.013720.225硫化氢

4.345.511.907.63-60.201.5571.3200.013140.100空气15.192——17.5013.40-192.501.3061.4010.02489—水蒸气

——8.6010.12—1.4911.3350.016170.3480二、自然 气中有机硫化合物的主要性质

自然 气中除含有H2S外，还含有