Pastas à base de sulfato de cálcio para aplicação em cimentação de poços de petróleo

• Main Author: Silvestre, Fiamma Raphaela da Silva
• Publication Date: 2015
• Format: Bachelor thesis
• Language: por
• Source: Repositório Institucional da UFRN
• Download full: https://repositorio.ufrn.br/handle/123456789/38308
• topic: Poços de petróleo.; Oilwells Cement.; Cimentação primária.; Sulfato de cálcio hemidratado-α.; Primary cementing.; Calcium sulfate hemihydrate-α.

The primary cementing is one of the most important stages of the drilling process, because it is which will give to the oilwell the mechanical stability and protect the coating tube. The Portland Cement is the most binder used as cement slurry to the cementing operation of oilwells. Due the great concern about the environment, because the process of getting the Portland Cement releases greenhouse gases, there are the necessity to develop studies of slurries with others precursors. Calcium sulfate hemihydrate-α is a material with great environment potential. Its process of getting the hemihydrate-α it involves low cost when it is compared to the Portland Cement. This turns the hemihydrate-α into a substitute of the Portland Cement. The present work aims to study the behavior of the systems with calcium sulfate hemihydrate-α as binder basis to the slurries of well’s cementing. The hemihydrate-α was characterized using X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Absorption Spectroscopy in the Infrared Region (IR), X-Ray Fluorescence (XRF), Thermal Characterization Techniques (TG/DTG) and Grain Size. Different water/plaster factors (FWP) were developed in this work (0,5, 0,6, 0,7 and 0,8) and the slurries were submitted to different kinds of cure (wet, fully wet and air) and temperature (27, 38 e 60°C). The technology property, applied to the oil industry, evaluated in these slurries was the compressive strength, and following, the slurry with the best FWP chosen (FWP 0,5) was characterized by X-Ray Diffraction, Scanning Electron Microscopy and Thermal Characterization Techniques (TG/DTG). According to the results the best system of slurries based on calcium sulfate hemihydrate-α was the 0.5 FWG to the 27°C and 38°C temperatures, because their values of compressive strength were above of the established by the NBR 9831, 2006 standard.