Effect of Different Water Content and Catalyst on the Performance of Heavy Oil Oxidation in Porous Media for In Situ Upgrading

Abstract

Enhanced heavy oil recovery by in situ combustion (ISC) is still restricted as an attractive thermal method because of difficulties with ignition, inefficient combustion, and unstable combustion fronts. This study illustrates how different water contents and CoFe 2 O 4 nanoparticles coated with oleic acid (OA), individually and synergistically, can be used in heavy oil oxidation for enhanced oil recovery through ISC. By means of X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, and dynamic light scattering, we characterized the synthesized bimetallic oxide catalysts with and without oleic acid as a capping agent. The size of the CoFe 2 O 4 and CoFe 2 O 4 @OA nanoparticles was evaluated by the ImageJ method in order to estimate the size distribution in different environments. The size−frequency analysis showed that the dimension of CoFe 2 O 4 nanoparticles in the presence of oleic acid as a capping agent due to uniformity and well distribution decreased to an average size of ∼20 nm. The oxidation of the heavy oil was studied by a self-designed thermo-effect cell containing a porous medium (PMTEC) and a laboratory-scale combustion tube. According to the results, the addition of 20% water content compared to 10% and 30% water content, and oil-dispersed CoFe 2 O 4 @OA compared to CoFe 2 O 4 nanoparticles led to a decrease in both low-temperature oxidation and high-temperature oxidation into lower temperatures through the reduction of energy barriers and the promotion of coke formation. The viscosity of recovered oil decreased from 2071 to 246 mPa•s after oxidation in porous media with a 20% water content and a CoFe 2 O 4 @OA catalyst. In addition, the SARA analysis showed that the oxidation of heavy oil in porous media with water content and catalyst reduced the heavy fractions such as resin and asphaltene contents from 20.9 and 5.9% to 9.7 and 2.5%, respectively, and increased the light fractions including saturate and aromatic contents from 28.7 and 44.3% to 41.3 and 46.5%, respectively. In addition, based on experimental data, a robust correlation was developed to predict oil viscosity using a genetic programming algorithm. The results showed that the developed method could predict oil viscosity with enough accuracy. On the basis of the viscosity reduction data, the combustion efficiency of heavy oil is in turn: heavy oil + CoFe 2 O 4 @OA > heavy oil + continued...

Improving the Performance of Heavy Oil Oxidation Using Oil-Soluble Copper-Based Catalysts in In Situ Combustion for the In Situ Upgrading Process

“…The Cu-Tall oil was prepared in the laboratory using the analogical method that we used in our previous works. ,, In order to do that, we applied the saponification reaction method for preparing the Cu-Tall oil as follows. normalR − normalC normalO normalO normalH + normalN normala normalO normalH → normalH 2 normalO + normalC normalH 3 normalC normalH 2 normalO normalH normalR − normalC normalO normalO normalN normala + normalH 2 normalO normalR − normalC normalO normalO normalN normala + normalC normalu normalS normalO 4 → normalH 2 normalO + normalC normalH 3 normalC normalH 2 normalO normalH ( R − C O O ) 2 normalC normalu + normalN normala 2 normalS normalO 4 …”

“…The Cu-Tall oil was prepared in the laboratory using the analogical method that we used in our previous works. ,, In order to do that, we applied the saponification reaction method for preparing the Cu-Tall oil as follows. …”

“…The airflow for the combustion reactions was adopted as 0.25 L/min. 42 During combustion, VCT is capable of obtaining temperature profiles of the oxidation reactions of the oil in porous medium. Additionally, the viscosity, elemental, and SARA analyses of recovered oil were performed to assess alterations in physical and chemical features following the combustion process in porous media.…”

“…For improving the efficiency of the oxidation process of the crude oil, various soluble catalysts in oil have been studied such as metal stearates including copper, iron, and nickel, copper naphthenate, and oil-dispersed transition metal-based catalysts based on oxides coated with oleic acid, such as Fe 2 O 3 and CoFe 2 O 4 . 8,30,42 Among these catalysts, copper stearate exhibited excellent performance due to its solubility in heavy oil environments and copper acting as a precursor for the in situ synthesis of CuO nanoparticles, which are responsible for heavy oil oxidation in high-temperature regions during ISC.…”

“…As a means to overcome these disadvantages, oil-soluble catalysts have received considerable attention because of their capabilities to dissolve and distribute in crude oil environments. For improving the efficiency of the oxidation process of the crude oil, various soluble catalysts in oil have been studied such as metal stearates including copper, iron, and nickel, copper naphthenate, and oil-dispersed transition metal-based catalysts based on oxides coated with oleic acid, such as Fe 2 O 3 and CoFe 2 O 4 . ,, Among these catalysts, copper stearate exhibited excellent performance due to its solubility in heavy oil environments and copper acting as a precursor for the in situ synthesis of CuO nanoparticles, which are responsible for heavy oil oxidation in high-temperature regions during ISC. Copper-based catalysts including CuO NPs are famous species for oxidation of different hydrocarbons, for example, alcohols, , carbon monoxide, toluene, , and formic acid …”