ASSESSMENT OF SCALE FORMATION IN THE COLUMN OF AN OIL AND NATURAL GAS PRODUCING WELL: A CASE STUDY

The present study investigated the influence of depth, pressure and temperature on the composition and behavior of scale formation along a column in a well that produces oil and natural gas. The objective was to improve treatments to remove precipitates formed on the column surface. Ten samples of residues were collected from several points along the production column (from 15.4 m to 4061.5 m) that exhibited scale formation or corrosion problems. Dissolution tests were performed in organic acids. The predominant composition was defined and confirmed by dissolution assays and characterization was determined using X-Ray Diffractometry (XRD), X-Ray Fluorescence Spectrometry (XRF) and Scanning Electron Microscopy (SEM). Residues with distinct characteristics were observed in different proportions, showing a tendency to increase or decrease in mass with depth. The results indicate that correlations can be established between the type of scale formation and depth and, consequently, thermodynamic conditions (pressure and temperature).