Scientists from the Center for Energy and Petroleum Studies (Cepetro), from the National Center for Research in Energy and Materials (CNPEM) and the Federal University of Santa Catarina (UFSC) are united in a project that will scrutinize pre-salt rocks. The objective is to improve rock characterization techniques and rock-fluid interaction to obtain more precision in the interpretation of analysis results. In this way, it will be possible to develop more assertive modeling, capable of optimizing oil extraction and reducing operation costs.
The project is financed by Equinor, a Norwegian energy multinational, present in Brazil for over 20 years, which will invest R$42 million (R$22 million in CNPEM and R$20 million divided between Unicamp and UFSC) over four years .
One of the characteristics of pre-salt rock is the wide variation in the size of the pores where the oil is contained. In some of them, up to one person can fit. "To describe better relative displacement of the oil, taking into account the different scales of the pores, is essential to develop well-representative models”, explains the Professor Rosangela Lopes Moreno, coordinator of the Petroleum Reservoir Laboratory (Labore), associated with Cepetro.
Several methodological fronts will be developed by the work teams. “In our case, the methodology is divided into two stages. Basic petrophysics, in which dry rocks are evaluated, with magnetic resonance and tomographic images, and special petrophysics, in which fluids are also considered. We will bring new variables to the analysis, such as the wettability of the rock [whether there is oil stuck to the walls or not] and the amount of mobile oil”, says Moreno.
The tests to characterize the rock, the fluids and their displacement through the pores will then be replicated at CNPEM's Sirius — a particle accelerator that allows scientists to study in greater detail the nanocosm of molecules, living cells and materials such as rocks .
In the complex managed by CNPEM, three particle accelerators operate in an integrated manner that make electrons approach the speed of light within a ring measuring 518 meters in circumference. As they move, the particles are forced by powerful magnets attached to the ring – no less than 1.300 – to change trajectory, losing energy and emitting synchrotron light.
“At the Sirius Mahogany synchrotron beamline we will be able to emulate rocks on a microscopic scale, due to the high definition of this beamline. Therefore, we will analyze with extreme precision and speed all the properties of rocks and the fluids that flow through them. We will have much more clarity about the mechanisms involved in the rock-fluid interaction”, says Moreno.
According to the Unicamp researcher, several scientific advances will be obtained after processing data at Sirius, UFSC and Unicamp itself, mainly with regard to the behavior of oil inside rocks. Pre-Salt reservoirs have specific peculiarities and the oil is not always stored in the middle of the pores. Sometimes the liquid sticks to the rock walls. To resolve these questions, scientists will perform mathematical simulations based on real data on how to extract oil.
In addition to the scientific advancement itself, the project financed by Equinor will also collaborate with the improvement of LABORE's analysis infrastructure, through the purchase of equipment. Another important gain, according to Moreno, is the qualified information that will be generated by students from the Postgraduate course in Petroleum Engineering at Unicamp who participate in the project. “It is another form of return for the companies that finance us, as many of our graduates end up working in the market — not only in the oil sector, but in various areas related to energy and sustainability”, explains the researcher.
