Nanotechnology Applied to Thermal Enhanced Oil Recovery Processes: A Review

Recent advances in functional micro/nanomaterials for removal of crude oil via thermal effects

Crude oil is one of the most widely used energy and industrial raw materials that is crucial to the world economy, and is used to produce various petroleum products. However, crude oil often spills during extraction, transportation and use, causing negative impacts on the environment. Thus, there is a high demand for products to remediate leaked crude oil. Among them, oleophilic and hydrophobic adsorbents can absorb crude oil through thermal effects and are research hotspots. In this review, we first present an overview of wettability theory, the heating principles of various thermal effects, and the theory of reducing crude oil viscosity by heating. Then we discuss adsorbents based on different heating methods including the photothermal effect, Joule heating effect, alternating magnetic field heating effect, and composite heating effect. Preparation methods and oil adsorption performance of adsorbents are summarized. Finally, the advantages and disadvantages of various heating methods are briefly summarized, as well as the prospects for future research.

Power from Geothermal Resources as a Co-product of the Oil and Gas Industry: A Review

The increase in the global demand for energy and fossil fuel dependency is hindering efforts to reduce greenhouse gas (GHG) emissions. Geothermal resources supplement this increase in energy demand with reduced emissions because of their availability, base-load production profile, and climatic independence. Despite these advantages, the development of geothermal energy is limited because of different reasons such as subsurface exploration risk and high upfront capital cost for drilling and facility construction. However, similarities in infrastructure and operations between the oil and gas industry and the geothermal industry can optimize expense and development when exploiting geothermal resources. Thus, in this review, we present recent advances and applications of geothermal power systems in the oil and gas industry starting from the fundamentals and basic principles of geothermal energy and the organic Rankine cycle (ORC). These applications include the use of geothermal resources via abandoned wells, active wells, and paired thermal enhanced oil recovery processes with injection for fluid heating and energy production. Abandoned wells are alternatives that reduce costs in geothermal energy-use projects. The use of geothermal resources via active wells allows the valorization of a resource, such as the production of water, which is considered a byproduct of production activities in an oilfield. The use of thermally enhanced oil recovery processes enhances the energy conditions of fluids produced in the field, improving geothermal systems with fluids at higher temperatures. Finally, an overview is presented of the challenges and opportunities of geothermal energy in the oil industry where the requirement to improve the usage of technologies, such as the ORCs, with the working fluids used in the cycles, is highlighted. Furthermore, the importance of environmental studies and use of novel tools, such as nanotechnology, to improve the efficiency of geothermal energy usage is highlighted.

Development of Bio-Nanofluids Based on the Effect of Nanoparticles' Chemical Nature and Novel Solanum torvum Extract for Chemical Enhanced Oil Recovery (CEOR) Processes

This study aimed to develop novel bio-nanofluids using Solanum torvum extracts in synergy with nanoparticles of different chemical nature as a proposal sustainable for enhanced oil recovery (EOR) applications. For this, saponin-rich extracts (SRE) were obtained from Solanum torvum fruit using ultrasound-assisted and Soxhlet extraction. The results revealed that Soxhlet is more efficient for obtaining SRE from Solanum torvum and that degreasing does not generate additional yields. SRE was characterized by Fourier transformed infrared spectrophotometry, thermogravimetric analysis, hydrophilic-lipophilic balance, and critical micelle concentration analyses. Bio-nanofluids based on SiO₂ (strong acid), ZrO₂ (acid), Al₂O₃ (neutral), and MgO (basic) nanoparticles and SRE were designed to evaluate the effect of the chemical nature of the nanoparticles on the SRE performance. The results show that 100 mg L^-1 MgO nanoparticles improved the interfacial tension up to 57% and the capillary number increased by two orders of magnitude using this bio-nanofluid. SRE solutions enhanced with MgO recovered about 21% more than the system in the absence of nanoparticles. The addition of MgO nanoparticles did not cause a loss of injectivity. This is the first study on the surface-active properties of Solanum torvum enhanced with nanomaterials as an environmentally friendly EOR process.

Catalytic Decomposition of n-C7 Asphaltenes Using Tungsten Oxides–Functionalized SiO2 Nanoparticles in Steam/Air Atmospheres

A wide range of technologies are being developed to increase oil recovery, reserves, and perform in situ upgrading of heavy crude oils. In this study, supported tungsten oxide nanoparticles were synthesized, characterized, and evaluated for adsorption and catalytic performance during wet in situ combustion (6% of steam in the air, in volumetric fraction) of n-C7 asphaltenes. Silica nanoparticles of 30 nm in diameter were synthesized using a sol–gel methodology and functionalized with tungsten oxides, using three different concentrations and calcination temperatures: 1%, 3%, 5% (mass fraction), and 350 °C, 450 °C, and 650 °C, respectively. Equilibrium batch adsorption experiments were carried out at 25 ℃ with model solutions of n-C7 asphaltenes diluted in toluene at concentrations from 100 mg·L−1 to 2000 mg·L−1, and catalytic wet in situ combustion of adsorbed heavy fractions was carried out by thermogravimetric analysis coupled to FT-IR. The results showed improvements of asphaltenes decomposition by the action of the tungsten oxide nanoparticles due to the reduction in the decomposition temperature of the asphaltenes up to 120 °C in comparison with the system in the absence of WOX nanoparticles. Those synthesis parameters, such as temperature and impregnation dosage, play an important role in the adsorptive and catalytic activity of the materials, due to the different WOX–support interactions as were found through XPS. The mixture released during the catalyzed asphaltene decomposition in the wet air atmosphere reveals an increase in light hydrocarbons, methane, and hydrogen content. Hydrogen production was prioritized between 300 and 400 °C where, similarly, the reduction of CO, CH4, and the increase in CO2 content, associated with water–gas shift, and methane reforming reactions occur, respectively. The results show that these catalysts can be used either for in situ upgrading of crude oil, or any application where heavy fractions must be transformed.

Effect of Steam Quality on Extra-Heavy Crude Oil Upgrading and Oil Recovery Assisted with PdO and NiO-Functionalized Al2O3 Nanoparticles

This work focuses on evaluating the effect of the steam quality on the upgrading and recovering extra-heavy crude oil in the presence and absence of two nanofluids. The nanofluids AlNi1 and AlNi1Pd1 consist of 500 mg·L−1 of alumina doped with 1.0% in mass fraction of Ni (AlNi1) and alumina doped with 1.0% in mass fraction of Ni and Pd (AlNi1Pd1), respectively, and 1000 mg·L−1 of tween 80 surfactant. Displacement tests are done in different stages, including (i) basic characterization, (ii) waterflooding, (iii) steam injection at 0.5 quality, (iv) steam injection at 1.0 quality, (v) batch injection of nanofluids, and (vi) steam injection after nanofluid injection at 0.5 and 1.0 qualities. The steam injection is realized at 210 °C, the reservoir temperature is fixed at 80 °C, and pore and overburden pressure at 1.03 MPa (150 psi) and 5.51 MPa (800 psi), respectively. After the steam injection at 0.5 and 1.0 quality, oil recovery is increased 3.0% and 7.0%, respectively, regarding the waterflooding stage, and no significant upgrade in crude oil is observed. Then, during the steam injection with nanoparticles, the AlNi1 and AlNi1Pd1 increase the oil recovery by 20.0% and 13.0% at 0.5 steam quality. Meanwhile, when steam is injected at 1.0 quality for both nanoparticles evaluated, no incremental oil is produced. The crude oil is highly upgraded for the AlNi1Pd1 system, reducing oil viscosity 99%, increasing the American Petroleum Institute (API)° from 6.9° to 13.3°, and reducing asphaltene content 50% at 0.5 quality. It is expected that this work will eventually help understand the appropriate conditions in which nanoparticles should be injected in a steam injection process to improve its efficiency in terms of oil recovery and crude oil quality.

Catalytic Conversion of n-C7 Asphaltenes and Resins II into Hydrogen Using CeO2-Based Nanocatalysts

This study focuses on evaluating the volumetric hydrogen content in the gaseous mixture released from the steam catalytic gasification of n-C₇ asphaltenes and resins II at low temperatures (<230 °C). For this purpose, four nanocatalysts were selected: CeO₂, CeO₂ functionalized with Ni-Pd, Fe-Pd, and Co-Pd. The catalytic capacity was measured by non-isothermal (from 100 to 600 °C) and isothermal (220 °C) thermogravimetric analyses. The samples show the main decomposition peak between 200 and 230 °C for bi-elemental nanocatalysts and 300 °C for the CeO₂ support, leading to reductions up to 50% in comparison with the samples in the absence of nanoparticles. At 220 °C, the conversion of both fractions increases in the order CeO₂ < Fe-Pd < Co-Pd < Ni-Pd. Hydrogen release was quantified for the isothermal tests. The hydrogen production agrees with each material’s catalytic activity for decomposing both fractions at the evaluated conditions. CeNi1Pd1 showed the highest performance among the other three samples and led to the highest hydrogen production in the effluent gas with values of ~44 vol%. When the samples were heated at higher temperatures (i.e., 230 °C), H₂ production increased up to 55 vol% during catalyzed n-C₇ asphaltene and resin conversion, indicating an increase of up to 70% in comparison with the non-catalyzed systems at the same temperature conditions.

Physicochemical characteristics of calcined MnFe2O4 solid nanospheres and their catalytic activity to oxidize para-nitrophenol with peroxymonosulfate and n-C7 asphaltenes with air

Manganese ferrite solid nanospheres (MSNs) were prepared by a solvothermal method and calcined at various temperatures up to 500 °C. Their surface area, morphology, particle size, weight change during calcination, surface coordination number of metal ions, oxidation state, crystal structure, crystallite size, and magnetic properties were studied. The MSNs were used as catalysts to activate potassium peroxymonosulfate (PMS) for the oxidative degradation of para-nitrophenol (PNP) from water and for the oxidation of n-C₇ asphaltenes in flowing air at atmospheric (0.084 MPa) and high pressure (6 MPa). Mn was in oxidation states (II) and (III) at calcination temperature of 200 °C, and the crystalline structure corresponded to jacobsite. Mn was in oxidation states (III) and (IV) at 350 °C and in oxidation states (II), (III), and (IV) at 500 °C, and the crystalline structure was maghemite at both temperatures. MSN catalysts generated hydroxyl (HO·) and sulfate (SO₄^·-) radicals in the PMS activation and generated HO· radicals in the n-C₇ asphaltene oxidation. In both reactions, the best catalyst was MSN calcined at 350 °C (MSN350), because it has the highest concentration of Mn(III) in octahedral B sites, which are directly exposed to the catalyst surface, and the largest total and lattice oxygen contents, favoring oxygen mobility for Mn redox cycles. The MSN350 sample reduces the decomposition temperature of n-C₇ asphaltenes from 430 to 210 °C at 0.084 MPa and from 370 to 200 °C at 6.0 MPa. In addition, it reduces the effective activation energy by approximately 77.6% in the second combustion (SC) region, where high-temperature oxidation reactions take place.

Nano-Intermediate of Magnetite Nanoparticles Supported on Activated Carbon from Spent Coffee Grounds for Treatment of Wastewater from Oil Industry and Energy Production

This work focused on evaluating the adsorptive removal of crude oil using a nano-intermediate based on magnetite nanoparticles supported on activated carbon synthesized from spent coffee grounds and the subsequent catalytic oil decomposition to recover by-products and regenerate the support material. The magnetite nanoparticles were synthesized by the co-precipitation method and were used as active phases on prepared activated carbon. The amount of crude oil adsorbed was determined by adsorption isotherms. In addition, dynamic tests were performed on a packed bed to evaluate the efficiency of the removal process. Thermogravimetric analysis and mass spectrometry were used to evaluate the catalytic powder and the quantification of by-products. Contrasting the results with commercial carbon, the one synthesized from the coffee residue showed a greater affinity for the oil. Likewise, the adsorption capacity increased by doping activated carbon with magnetite nanoparticles, obtaining an efficiency greater than 10%. The crude oil decomposition was carried out successfully by thermal cracking, obtaining a 100% removal. The gas produced after decomposition contains light hydrocarbons such as C2H4 and CH4 and shows a decrease in polluting species such as CO and CO2, leading to greater environmental sustainability of the process.

Enhancing the Performance of HPAM Polymer Flooding Using Nano CuO/Nanoclay Blend

A single polymer flooding is a widely employed enhanced oil recovery method, despite polymer vulnerability to shear and thermal degradation. Nanohybrids, on the other hand, resist degradation and maintain superior rheological properties at different shear rates. In this article, the effect of coupling CuO nanoparticles (NPs) and nanoclay with partially hydrolyzed polyacrylamide (HPAM) polymer solution on the rheological properties and the recovery factor of the nanohybrid fluid was assessed. The results confirmed that the NP agents preserved the polymer chains from degradation under mechanical, chemical (i.e., salinity), and thermal stresses and maintained good extent of entanglement among the polymer chains, leading to a strong viscoelastic attribute, in addition to the pseudoplastic behavior. The NP additives increased the viscosity of the HPAM polymer at shear rates varying from 10–100 s−1. The rheological properties of the nanohybrid systems varied with the NP additive content, which in turn provided a window for engineering a nanohybrid system with a proper mobility ratio and scaling coefficient, while avoiding injectivity issues. Sandpack flooding tests confirmed the superior performance of the optimized nanohybrid system and showed a 39% improvement in the recovery ratio relative to the HPAM polymer injection.

NiO, Fe2O3, and MoO3 Supported over SiO2 Nanocatalysts for Asphaltene Adsorption and Catalytic Decomposition: Optimization through a Simplex–Centroid Mixture Design of Experiments

The main objective of this study was to evaluate the effect of functionalized silica nanoparticles with Fe2O3, NiO, and MoO3 metal oxides on the decomposition of asphaltenes, through an experimental simplex–centroid mixture design for surface area, asphaltene adsorption, and activation energy. The experimental nanoparticle surface area was measured by adsorption of N2. Adsorption isotherms, and the subsequent oxidation process of asphaltenes, were performed through batch adsorption experiments and thermogravimetric analysis, respectively. Among the monometallic systems, the presence of iron increased the affinity between the nanoparticle and the asphaltenes, and a higher metal oxide load increased the adsorptive capacity of the system. For the pairings evaluated, there was better synergy between iron and nickel, with the participation of the former being slightly superior. In the mixture design that included three transition elements, the participation of molybdenum was not significant, and the adsorption of asphaltenes was dominated by the active sites formed by the other two transition element oxides. The mixture design created to minimize the activation energy showed that the interaction of the three transition elements is important and can be evidenced in the interaction coefficients.

Effect of Nanoparticles with Different Chemical Nature on the Stability and Rheology of Acrylamide Sodium Acrylate Copolymer/Chromium (III) Acetate Gel for Conformance Control Operations

During enhanced oil recovery (EOR), reservoir heterogeneities and fluids distributions promote preferential flow channels formation. Therefore, different types of gels have been proposed to improve swept efficiency on chemical flooding by plugging high permeability zones. The purpose of this article is to evaluate the effect that nanotechnology has on the inhibition of syneresis and the rheological properties of the Acrylamide Sodium Acrylate Copolymer/Chromium (III) Acetate gel system for conformance applications in mature reservoirs. Thus, a methodology is proposed in four stages: First, (I) nanoparticles synthesis, and characterization, followed by (II) bottle tests to monitor gelation kinetics and syneresis degree at 70 °C, then (III) description of the rheological evaluation on static and dynamic conditions to calculate gelation time and viscoelastic modulus (G’ and G”), and finally (IV) the displacement test with the best gel system in the presence of nanoparticles. Results showed that the best nanoparticle was the chromium oxide (Cr₂O₃), which represented the lesser syneresis degree and increased gelation time. Syneresis of gel samples in the presence of Cr₂O₃ at day 30 was under 1% for gels prepared with 4000, 6000, and 8000 mg·L⁻¹ of polymer, and polymer to crosslinker ratio (p/c) of 40:1. Regarding SiO₂, MgO, and Al₂O₃ nanoparticles, results show an improvement of gel strength. However, their thermal stability in terms of syneresis was lower. Displacement test in a triple parallel Slim Tube was able to recover an additional 37% of oil of the total oil present in the sandpacks, confirming the effectivity of the system when 100 mg·L⁻¹ of Cr₂O₃ nanoparticles are included.

Improvement of Steam Injection Processes Through Nanotechnology: An Approach through in Situ Upgrading and Foam Injection

This study aims to evaluate a high-performance nanocatalyst for upgrading of extra-heavy crude oil recovery and at the same time evaluate the capacity of foams generated with a nanofluid to improve the sweeping efficiency through a continuous steam injection process at reservoir conditions. CeO2±δ nanoparticles functionalized with mass fractions of 0.89% and 1.1% of NiO and PdO, respectively, were employed to assist the technology and achieve the oil upgrading. In addition, silica nanoparticles grafted with a mass fraction of 12% polyethylene glycol were used as an additive to improve the stability of an alpha-olefin sulphonate-based foam. The nanofluid formulation for the in situ upgrading process was carried out through thermogravimetric analysis and measurements of zeta potential during eight days to find the best concentration of nanoparticles and surfactant, respectively. The displacement test was carried out in different stages, including, (i) basic characterization, (ii) steam injection in the absence of nanofluids, (iii) steam injection after soaking with nanofluid for in situ upgrading, (iv) N2 injection, and (v) steam injection after foaming nanofluid. Increase in the oil recovery of 8.8%, 3%, and 5.5% are obtained for the technology assisted by the nanocatalyst-based nanofluid, after the nitrogen injection, and subsequent to the thermal foam injection, respectively. Analytical methods showed that the oil viscosity was reduced 79%, 77%, and 31%, in each case. Regarding the asphaltene content, with the presence of the nanocatalyst, it decreased from 28.7% up to 12.9%. Also, the American Petroleum Institute (API) gravity values increased by up to 47%. It was observed that the crude oil produced after the foam injection was of higher quality than the crude oil without treatment, indicating that the thermal foam leads to a better swept of the porous medium containing upgraded oil.