HIGH-PRESSURE BEHAVIOR OF HYDROCARBONS - JOULE-THOMSON EXPANSION OF GAS-CONDENSATES

This paper presents calculations of Joule-Thomson inversion effects in high-pressure-high-temperature gas condensates. Isenthalpic expansion s were modeled for several gas condensate mixtures reported in literat ure using the Soave-Redlich-Kwong and the Peng-Robinson equations of s tate. The calculations confirmed qualitatively the heating of gas cond ensates at expansion. Although reservoir temperatures are in the regio n where cooling occurs, i.e., inside the inversion curve, it was shown that reservoir pressures lie outside this region, and that the temper ature will increase until the inversion curve is reached. The calculat ed temperature increases are not very large. Although exact values dep end on fluid composition, reservoir conditions, and pressure drop, typ ical calculated temperature increases are in the range of 10-30 degree s C for reservoir pressures of 1000 bar. A sensitivity study showed th at both reservoir pressure and fluid composition greatly affect the te mperature increase, With increasing pressures and increasing amounts o f heavy constituents present in gas condensate mixtures, the maximum p ossible temperature effect will also increase. Unfortunately, due to l ack of experimental information, the reliability of the calculated res ults could not be verified.