| Abstract |
Scaling or solid deposition generally occurs inside geothermal wells which produce two-phase geothermal fluid. This occurrence will lead to the blockage of fluid flow in geothermal wells. Certain geothermal fields encounter sulfide scaling inside the production wellbore, for example the Dieng geothermal field. The solution to overcome sulfide scaling is by doing workover operation. However, the growth of sulfide scaling inside the wellbore has never been modeled. The necessity for modeling the growth of scaling is important, as by knowing the scaling growth inside the wellbore, we would know the depth of scaling. Moreover, workover operation can be conducted before scaling occurs and fills up the production well completely. This study is attempted to develop mathematical models to find a solution for predicting the sulfide scaling in the geothermal wells, focusing on galena and sphalerite. The mathematical model was developed by integrating the solubility-temperature corelation and two-phase pressure drop correlation in a vertical production well. The outcome of this study would visualize the increasing thickness of sulfide deposition inside the wellbore per annum. Then, sensitivity analysis was applied in several parameters, for example pH, the amount of Pb2+, Zn2+, bottomhole flowing pressure and mass flowrate. The results showed that the amount of Pb2+, Zn2+ and mass flowrate had an effect on the amount of deposition, whereas the change of the bottomhole pressure would change the initial depth of deposition. |