Nitrogen Flooding of Stratified Gas-Condensate Reservoirs

摘要

Gas injection in gas-condensate reservoirs often yields high recoveries, since noretrograde condensation is present. A complication of nitrogen injection is the occurance of condensate dropout in the mixing zone. This is particularly harmful in a stratified reservoir, where the mixing zone is larger than in a homogeneous medium. Therefore severe dropout can be expected. In this thesis we present a simulation study is nitrogen flooding of a two-layer stratified reservoir. The objectives of the study are: (1) to identify the condensate dropout mechanisms and (2) to quantify the recovery losses due to condensate dropout.