1Tehran Energy Consultants, Khoramshahr St., Tehran 1554614313, I.R. IRAN
2Department of Chemical Engineering, Engineering Faculty, Persian Gulf University, Bushehr, I.R. IRAN
3Faculty of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, I.R. IRAN
In this work, studies of underground gas storage (UGS) were performed on a partially depleted, naturally fractured gas reservoir through compositional simulation. Reservoir dynamic model was calibrated by history matching of about 20 years of researvoir production. Effects of fracture parameters, i.e. fracture shape factor, fracture permeability and porosity were studied. Results showed that distribution of fracture density affects flow and production of water, but not that of gas, through porous medium. However, due to high mobility of gas, the gas production and reservoir average pressure are insensitive to fracture shape factor. Also, it was found that uniform fracture permeability distribution enhances communication within reservoir and consequently more pressure support is obtained by water bearing of aquifer. Effect of aquifer on the reservoir performance was studied, and it was found that an active aquifer can reduce condensate drop out around the well bore. On the other hand, water invasion is an important issue which may kill the well. Results showed that use of horizontal wells is superior to vertical wells in order to avoid detrimental effects of active aquifer.
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