Blenda contendo cimento Portland Classe G e resíduo da produção de argamassa para cimentação de poços petrolíferos de altas temperaturas

Abstract

Exploring new oil fields remains a constant pursuit, as well as increasing production in fields considered mature, in order to increase reserves and increase global energy supply. For this, optimizations are needed that contribute to the reduction of operating costs in drilling wells and that are more sustainable, in order to reconcile the use of new technologies while ensuring greater integrity of the wells constructed and lower environmental impacts. With the advent of technology, it is already common to reach more aggressive oil and gas reservoir scenarios when it comes mainly to parameters such as high temperature and high pressure. However, under these conditions there are greater challenges to be considered, especially in relation to the cementation project, since at temperatures above 110 °C the cement undergoes changes in its hydration, which tend to favor the formation of phases with greater permeability and causing the retrogression of its mechanical resistance, making the cement vulnerable to the hydraulic isolation of the well and compromising its integrity. On the other hand, the industrial sector, in general, generates a significant amount of waste, many of which do not have adequate applications or destinations. As an example, the mortar production industry generates a by-product that was previously discarded and the objective of this work is to apply this waste in cement pastes subject to the high temperatures and pressures of oil and gas wells in order to add value through the development of a commercial blend to be potentially used in the cementing of wells as a technologically efficient product that provides a significant reduction in the use of cement without losing the required properties, which also contributes to the reduction of costs and environmental impacts. The studies were conducted with the characterization of the residue using X-ray diffraction techniques, granulometric analysis and analysis of chemical composition, and the pastes were formulated with different proportions of the residue + cement blend in curing scenarios in high and low conditions. Temperature and pressure with subsequent characterization of the formed phases and technological tests of resistance to compression, comparing the data obtained with the data of standard pastes. Preliminary results demonstrate the potential of using a cement blend with mortar residue to replace the currently marketed products, favoring positive impacts, being considered a sustainable product, providing adequate mechanical properties to operational requests and with an environmental appeal that, still, can generate cost reduction in the manufacture of pastes, facilitating the viability of operations in several fields, with high temperature conditions and where thermal recovery techniques will be applied