Prediction of oilfield scale deposition along the wellbore: Fundamentals and applications

Abstract

In recent years, some oil producing wells in Cuu Long basin have had serious problems with oilfield scale deposition. Mineral scales (mainly CaCOj) appears massively at high concentrations, causing obstruction of the pipe flow and thus leading to the reduction in oil production. Although oilfield scale deposition problems have occurred quite frequently in Vietnam, they have not attracted much attention from researchers.

The main contents presented in this paper include: (i) Calculation of the scaling tendency and the amount of scale deposition when it occurs; (ii) Study of the influences that flow dynamics has on scale deposition along the wellbore; (iii) Prediction of mineral scale deposition in the well X-1.

The study on well X-l shows that there exists mineral scale deposit (mainly CaGOj) with the estimated amount of scale deposit greater thatn 12mg/L, In addition, the comparison between the results from this study with those from ScaleChem software (Old System) shows that the difference in results between the two approaches is insignificant (less than 1%) and thus prove the reliability of the computational workflow used in this study.

In addition, an important contribution of this study compared to that by H.Long et al. (2016) [1] is that the influence of flow dynamics on the mineral scale deposition was taken into account in predicting the amount of scale deposit along the wellbore of X-1 with the combination of ScaleChem (OLI System) and PIPESIM (Schlumberger).