Estudo de pastas de cimento Portland com adições de cinzas de carvão mineral para uso na cimentação de poços de petróleo

• Ano de defesa: 2016
• Autor(a) principal: Cirino, Miguel Adriano Gonçalves
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Palavras-chave em Português: Engenharia de estruturas; Cimentação de poços de petróleo; Cinzas de carvão mineral; Pastas de cimento Portland; Resíduos industriais
• Link de acesso: http://www.repositorio.ufc.br/handle/riufc/23347

Among the Portland cements used for the cementing of oil wells in Brazil, the CPP Class G and the Special Class CPP stand out. These have more factory control, logistical and production costs than ordinary cements. The formulated pastes, with cements for civil construction, do not meet the normative requirements of the Brazilian Institute for regulamentation NBR 9831/2006, especially regarding the compressive strength. In order to improve the compressive strength properties of the pulps, it is necessary to modify its microstructure. For this purpose, it is possible to make use of mineral additives, such as the ash from mineral coal combustion, which in the state of Ceará is abundant as a residue from the Pecém thermoelectric plants, becoming an environmental liability and an economic problem for companies. The aim of this research is to study the feasibility of using CPII F 32 and CP V cements, with lower production and distribution costs than cements for oil wells, with partial replacement of cements by two types of mineral coal ashes CV1 (gray ash) and CV2 (light gray), in the proportions of 0% (paste without additions), 5% and 10% by mass of the cement, for application in well cementing with pulps formulated with density of 14.5 lb / gal (1.737 g / cm 3). In order to evaluate the formulated pastes, mineral cements and ashes were characterized in terms of chemical, physical and microstructural aspects, as well as formulated pastes for physic-chemical requirements and technological API tests (consistometry, free water content, (NBR 9831 (2006) and API SPEC 10A (2002)), In addition to evaluate the evolution of the compressive strength at the ages of 24 hours, 7 days and 28 days at the curing temperature of 38 ° C. It is concluded that the formulated pastes presented good results in terms of free water content, consistometry and compressive strength with 8 hours of curing, besides developing good compressive strength at 28 days, with results close to or higher than the pastes formulated with the cements Portland CPP grade G and Special Grade CPP, at a pulp density of 14.5 lb / gal, when compared to similar searches. The results allow the feasibility of the use of pulps formulated for application in shallow oil wells, especially for the CPV10CV2 pulp, with better results for API technological tests