A nickel-based catalyst precursor has been synthesized for in-situ upgrading of heavy crude oil that is capable of increasing the efficiency of steam stimulation techniques. The precursor activation occurs due to the decomposition of nickel tallate under hydrothermal conditions. The aim of this study is to analyze the efficiency of in-situ catalytic upgrading of heavy oil from laboratory scale experiments to the field-scale implementation in Boca de Jaruco reservoir. The proposed catalytic composition for in-reservoir chemical transformation of heavy oil and natural bitumen is composed of oil-soluble nickel compound and organic hydrogen donor solvent. The nickel-based catalytic composition in laboratory-scale hydrothermal conditions at 300°С and 90 bars demonstrated a high performance; the content of asphaltenes was reduced from 22% to 7 wt.%. The viscosity of crude oil was also reduced by three times. The technology for industrial-scale production of catalyst precursor was designed and the first pilot batch with a mass of 12 ton was achieved. A «Cyclic steam stimulation» technology was modified in order to deliver the catalytic composition to the pay zones of Boca de Jaruco reservoir (Cuba). The active forms of catalyst precursors are nanodispersed mixed oxides and sulfides of nickel. The pilot test of catalyst injection was carried out in bituminous carbonate formation M, in Boca de Jaruco reservoir (Cuba). The application of catalytic composition provided increase in cumulative oil production and incremental oil recovery in contrast to the previous cycle (without catalyst) is 170% up to date (the effect is in progress). After injection of catalysts, more than 200 samples from production well were analyzed in laboratory. Based on the physical and chemical properties of investigated samples and considering the excellent oil recovery coefficient it is decided to expand the industrial application of catalysts in the given reservoir. The project is scheduled on the fourth quarter of 2021.

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The paper includes the scheme of surfactant composition selection and the approach to evaluate potential results of injection for Central-Khoreiver Uplift (CKU) fields with carbonate reservoirs. Several scenarios of surfactant composition injection were studied, using high salinity treated formation water (up to 210 g/l) without applying salinity gradient. The first step of surfactant composition selection included testing of water solution stability in formation water that is characteristic for CKU conditions. Then interfacial tension of surfactant water solution with oil was measured, as well as adsorption properties. The target values of interfacial tension were set in the range around 10-2, and not higher than 10-1 mN/m. Filtration experiments on composite core model were conducted to evaluate the efficnency of selected composition. Development and tuning of linear model for the filtration experiment matched the laboratory results. Obtained parameters are included into the sector model of field development unit, considering the conversion of one of the wells to injection of chemicals. The paper presents preliminary evaluation of technological efficiency for the selected scheme of composition injection. The approach presented in the current paper can be used to plan injection of surfactant-based compositions into carbonate formation with properties that are similar to investigated values. Applying surfactants that are compatible with high salinity formation water makes possible to use treated produced water as injection medium and it decreases the costs of mix water preparation.