SIMULATION OF SALT PRECIPITATION IN GAS PRODUCING WELLS

Salt precipitation is a chronic problem in gas reservoirs in the course of gas production. As the pressure decreases in the reservoir, the gas in contact with the formation water causes water vaporization in order to satisfy the thermodynamic equilibrium condition. The evaporation is more sever in near well bore area because of higher pressure drop in this region. Evaporation of the formation water leads to an increase in the brine concentration which leads to salt deposition and pore throat plugging near well bore. This formation damage, changes the reservoir properties such as permeability and porosity. In this study the salt precipitation has been simulated using a commercial software, ECLIPSE 300 and the effects of formation damage on the reservoir performance are investigated. Besides the impact of reservoir fluid property such as salinity of the reservoir brine, as well as the impact of reservoir rock properties, such as absolute permeability, on the amount of evaporated water has been investigated. The results show that, in the case of production with constant flow, evaporation of water is more significant when absolute permeability of the reservoir rock is lower. Furthermore, the evaporation of water is lower, in the cases with higher salinity of the brine

کلیدواژه ها:

Simulation ، ECLIPSE ، formation damage ، evaporation ، salt precipitation ، permeability reduction