Effect of Nanoadditives on Drilling Cement

Abstract

Nanomaterials have emerged as crucial components in enhancing drilling cement properties, garnering significant interest from researchers and the drilling industry. Previous studies have explored nanoparticles, carbon nanotubes, and cellulose nanofibers, revealing their ability to improve mechanical strength, bonding, sulfate resistance, thermal stability, and rheological properties while reducing setting time, porosity, and permeability. This research delves into fundamental variables impacting nanomaterial-infused cement quality, including types, concentrations, and environmental conditions like temperature and pressure. Results underscore the substantial performance enhancements achievable through nanomaterial additives, fostering operational efficiency in drilling. Moreover, the study identifies potential drawbacks of certain nanoparticles and establishes optimal dosages for cement formulations, aiding drilling engineers in refining their approaches. Additionally, the investigation extends to the combined use of nanomaterials in hybrid and composite forms, offering insights into further enhancing drilling cement quality. Ultimately, this research advances our comprehension of nanomaterial effects on construction materials and drives technological progress in drilling by optimizing their utilization.

1. Introduction

Drilling cement is a composite material utilized as a specialized fluid to fill the void between the wellbore wall of an oil or gas well and casing. As a result, it ensures mechanical stability and proper functioning of the wellbore structure, thus guaranteeing the mechanical stability and proper performance of the well structure [1, 2, 3]. Drilling cement primarily consists of powdered materials such as Portland cement, pozzolans such as ash derived from oil or coal combustion, and water [4, 5, 6].

Drilling cement must possess characteristics such as mechanical strength, time stability, appropriate rheology, and chemical resistance in order to effectively address issues related to fluid loss and wellbore performance [7, 8, 9].

The classes of drilling cement, ranging from A to H as defined by the American Petroleum Institute (API), delineate various characteristics and uses for each type of cement [10, 11].

In drilling cement, the use of additives aims to enhance cement properties, control erosion, increase mechanical strength, reduce setting time, and address other necessary characteristics. Table 1 highlights some of the materials used along with their chemical formulas.

Application	Example additives	Formula	References
Setting time modifiers	Triethanolamine	C6H15NO3	[12, 13]
	diethanolamine	C4H11NO2
Fluid-loss control	Polymers	—	[14]
	Silicates	${\left[Si{O}_{4-x}^{\left(4-2x\right)-}\right]}_n$
	Solid materials	—
Retarders	Borax	$N{a}_2\left[{\text{B}}_4{\text{O}}_5{\left(OH\right)}_4\right].8{\text{H}}_2\text{O}$	[15, 16]
	Citrates	—
	polycarboxylate	—
Strength enhancers	Nano- and micro-silica	SiO2	[17, 18]
	Polymer fibers	—
Blended additives	Silica foam mixtures	—	[19, 20]
	Modified polymers	—
	Fiber additives	—

Table 1.

Some drilling cement additives and applications.

It should be noted that the selection and use of additives depend on the specific requirements of each project and environmental conditions. Proper selection of additives and precise control in the composition of drilling cement improve cement performance and enhance drilling efficiency [21].

2. Nanoadditives

The application of nanotechnology in the drilling industry plays a vital role in enhancing the performance of drilling cement. Nanoparticles are introduced as novel and advanced additives to drilling cement to improve its properties and alleviate issues related to bonding, fluid loss, and cement weight [22, 23, 24, 25].

One of the advantages of using nanoparticles in drilling cement is the optimization of cement weight. By employing lightweight nanoparticles, the weight of cement decreases, leading to cost reductions and increased drilling efficiency [26]. Furthermore, by adjusting the nanoparticle composition, cement weight can be precisely and reliably regulated, addressing issues associated with excessive or insufficient cement weight [27].

However, the use of nanoparticles in drilling cement comes with its own drawbacks. One of these is the high costs associated with nanoparticle production. Additionally, concerns regarding nanoparticle stability in drilling conditions and their effects on cement service life are subject to debate. Moreover, the possibility of nanoparticle transfer into the soil-water system poses environmental risks that require more thorough examination beyond public opinions [28, 29].

In summary, the use of nanotechnology for optimizing cement weight and controlling fluid loss in drilling cement through nanoparticle additives brings new capabilities to the drilling industry. This technology has the potential to enhance drilling cement efficiency, reduce costs, and provide better control over cement properties. However, for optimal use of nanotechnology in drilling, further research is needed on the stability and environmental effects of nanoparticles, as well as improving production and utilization processes [30]. The following section will delve into the impact of some nanomaterials based on previous studies.

2.1 Metal oxides

2.1.1 Nano-silica

Nano-silica finds crucial applications in the petroleum industry. Its properties include enhanced reactivity, mechanical strength, and thermal stability. In petroleum engineering, this nanoparticle has been found to aid in enhanced oil recovery, strengthen cement for wellbore stability, improve drilling fluids, and serve as a catalyst for refining processes, contributing to increased efficiency and productivity in oil operations [31, 32].

In 2012, Choolaei et al. conducted a study by preparing different concentrations of slurries to investigate the effect of nano-silica. The free water content in the slurries was measured to demonstrate their stability across a wide range of densities. The results showed no free water in the cements designed with nano-silica. Furthermore, the addition of nano-silica reduced setting time and porosity. The cements designed with this nanoparticles exhibited the lowest permeability and demonstrated improvements in flexural and compressive strength tests [33].

In 2012, Santra et al. presented a review of the aforementioned practical concepts, focusing on understanding the role of multi-walled carbon nanotubes, nano-silica, and nano-alumina in the hydration chemistry of oil well cement. The impact of incorporating these materials into oil well cement on its physical properties has been discussed. The objective of conducting microcalorimetry experiments at varying temperatures was to gain insight into the contrasting acceleration mechanisms exhibited by a standard cement accelerator like CaCl₂ when compared to nano-silica or nano-alumina. For silica-related slurries, greater solubility leads to higher acceleration, where solubility depends on nanoparticle size (larger is better) and crystallization [34].

According to the research by El-Gamal et al. [35], cement containing nano-silica exhibited better compressive strength. Furthermore, SEM micrographs indicated improvements in the fine structures of slurries prepared with nano-silica. Ultimately, the optimal dosage of 1% nano-silica was reported for two temperatures, 25 and 90°C [35].

In 2012, Patil and Deshpande conducted a study examining how silica nanoparticles impact the quality of drilling cement. They incorporated nano-silica into the cement mixture with the intention of attaining elevated initial strength. Nano-silica also contributed to increasing the final compressive strength and assisting in fluid loss control. Ultimately, it was demonstrated that by using the appropriate amount of nano-silica, cement slurries with low rheology and good mechanical properties could be designed while maintaining control over fluid loss [36].

In 2010, Roddy et al. investigated the influence of nanoparticle silica particle size on fluid loss and cement strength. They examined the impact of nano-silica particles with different sizes and micro-silica on the properties of latex-modified slurries. The results they presented are summarized in Table 2 [37].

Silica Type	Thick time to 70 Bc (Hr:Min)	Compressional strength (psi)	Shear-bond strength (psi)	Tensile strength (psi)
30 nm particulate silica	2:43	428	169	148.28
10 nm particulate silica	5:00	402	51	14.72
Amorphous silica	14:32	211	98	95.5
Crystalline silica	20:00+	252	37.2	102.16
Colloidal silica	20:00+	374	42.4	84.71

Table 2.

Impact of silica particle size and type on cement properties [37].

In the study by Ershadi et al. conducted in 2011, the use of nano-silica in slurry composition improved the mechanical and rheological properties of both the cement slurry and the cement itself. By incorporating very fine silica particles into the cement, porosity and permeability were significantly reduced by 33.3% and 99%, respectively, and the compressive strength increased from 1486 psi to 3801 psi. Ultimately, an optimal amount of nano-silica in the slurry composition was proposed. The new slurry formulation, characterized by low porosity, low permeability, and high compressive strength, is suitable for regions with high gas migration potential [38].

According to a study by Liu et al. [39], nano-silica accelerates the cement hydration process and enhances the mechanical integrity. Utilizing nano-silica particles led to an enhancement in both the compressive and flexural strength of the mortar samples. However, excessive use of nano-silica can lead to performance degradation. The optimal content of nano-silica in the mortar was calculated to be 3.0% by weight [39].

The effect of nano-silica on cement resistance against sulfate attack was investigated by Luswata et al. [40]. For this purpose, five concentrations of nano-silica (0, 0.3, 0.6, 0.9, and 1.2%) were maintained in solutions at temperatures of 23, 40, 65, 70, and 80°C for 21 days. At temperatures exceeding 65°C, the sulfate resistance of the cement improved for each percentage of nano-silica substitution. Control samples with 0% nano-silica exhibited the lowest performance at all temperatures. Concentrations higher than 1.2% and 0.6% nano-silica substitution showed the highest resistance between temperatures of 23 to 65°C. The concentration of 0.3% demonstrated a more suitable performance between temperatures of 65 to 80°C [40].

In 2017, Piklowska et al. investigated the impact of these nanoparticles on cement properties under high temperature and pressure conditions. The results showed that adding nano-silica reduces the rate of strength reduction and imparts high compressive strength to the cement. Low permeability, fluid loss control, and strength regression contribute significantly to the increased compressive strength of the cement mixture [41].

In a study done by Hadi and Ameer in 2017, addition of 40 nm nano-silica particles to cement resulted in a reduction in setting time and an increase in compressive strength at a temperature of 38°C. Additionally, rheological properties improved, and free water content decreased. The density change with the addition of these nanoparticles was not significantly pronounced. Moreover, the effect of these nanoparticles on free water content and rheological properties is greater than that of nano-alumina [42].

In 2019, Rita et al. investigated the impact of these nanoparticles, alongside the presence of bagasse ash, on the strength of cement. Experiments were conducted by adding bagasse ash and nano-silica at a temperature of 120°F and a pressure of 14.7 psi in a water bath for 24 hours. Various scenarios were investigated, and the optimal compressive strength of 991 psi and shear strength of 97 psi were achieved at bagasse and nano-silica concentrations of 5% and 0.019%, respectively [43].

2.1.2 Olivine nano-silica

Olivine nano-silica, derived from olivine minerals, offers exceptional adsorption and catalytic properties due to its nano-sized particles. It plays a crucial role in the petroleum industry, by enhancing oil refining processes. Its potent adsorption capacity removes impurities from crude oil, while its catalytic properties enable more efficient and eco-friendly conversion reactions, advancing efficiency and sustainability of petroleum operations [44, 45].

The impact of olivine nano-silica was studied by Quercia et al. [46]. The kinetic dependency of cement hydration on baking temperature, activation energy, and degree of hydration of cement slurries were assessed under isothermal and isobaric conditions. The apparent activation energy of different slurries with olivine nano-silica was estimated using static and dynamic methods. Furthermore, the beneficial effect of adding olivine nano-silica to ordinary-density slurries was investigated using standard methods prescribed by relevant API standards, including setting time, rheology, thickening time, and ultrasonic compressive strength determination. The favorable impact of adding olivine nano-silica on stability, rheology, and degree of hydration of cement slurries was demonstrated. Ultimately, the potential use of olivine nano-silica as an accelerator and enhancer of mechanical properties for oil well cement composites was shown [46].

2.1.3 Nano-alumina

Nano-alumina, derived from aluminum oxide, boasts high surface area and thermal stability, yielding potent catalytic and adsorption capabilities. In the petroleum sector, it revolutionizes refining processes as an efficient catalyst, accelerating reactions and curbing energy usage, thus bolstering sustainability and innovation [47, 48].

In a study conducted by Santra et al. [34], it was determined that for nano-alumina slurries, there may not be significant chemical effects. However, a slight increase in the rate of strength development could stem from the adsorption of some water molecules onto high-surface-area crystalline alumina particles, leading to an actual reduction in the water content present in the slurry [34].

In 2011, Nazari and Riahi conducted a study exploring the influence of lime water on the strength and water absorption characteristics of cement blended with Al₂O₃ nanoparticles. Their investigation involved the partial replacement of Portland cement with Al₂O₃ nanoparticles, averaging 15 nm in size. The resultant samples underwent saturation with both water and lime water for specific curing durations. Incorporating nano-alumina up to a concentration of 2% by weight led to an enhancement in water permeability resistance for specimens subjected to lime water curing, while this improvement was observed at a concentration of 1% by weight for samples cured in regular water. It was observed that lime water had a diminishing effect on the strength of cement without nanoparticles in comparison to water-cured cement. However, when subjected to lime water saturation, a reinforcing gel formed around the Al₂O₃ nanoparticles, resulting in increased permeability resistance and heightened strength. Furthermore, the Al₂O₃ nanoparticles functioned as effective nanopore fillers, reducing detrimental porosity and thereby reinstating the pore structure of the samples [49].

Li et al. conducted a study in 2006 to explore the impact of introducing nano-alumina at various curing durations and volume proportions of the nanoparticle. Their investigation aimed to evaluate the influence of nano-alumina on the elastic modulus and compressive strength of cement composites. Cylindrical samples measuring 40 × 20 mm were fabricated, each containing distinct volume ratios of nano-alumina, and were subjected to testing at different curing intervals (3 days, 7 days, and 28 days). The experimental results revealed a noticeable improvement in both the compressive strength and elastic modulus of the mortar upon the incorporation of nano-alumina within the matrix. Notably, when the volume proportion of nano-alumina reached 5%, the composite’s elastic modulus exhibited an impressive 143% increase after 28 days. Similarly, at a volume proportion of 7%, the compressive strength of the composites surged by 30% within 7 days. The introduction of nano-alumina into the mortar led to heightened density in the interfacial transition zone, a reduction in cement porosity, and, consequently, a significant enhancement in the elastic modulus and compressive strength of the mortar infused with nano-alumina [50].

In a study in 2015 by Liu et al., the use of alumina nanoparticles led to a reduction in compressive and flexural strength, which became more pronounced over time [39].

Also, according to a research conducted by Hadi and Ameer in 2017, the addition of 80 nm diameter nano-alumina particles to cement resulted in a reduction in setting time and an increase in compressive strength at a temperature of 38°C. Furthermore, rheological properties improved, and free water content decreased. The density change with the addition of these nanoparticles was not significantly pronounced. Moreover, the impact of this nanoparticle on compressive strength and thickening time is greater than that of nano-silica [42].

2.1.4 Nano-zinc oxide

Nano-zinc oxide, renowned for its minuscule size and exceptional attributes, proves indispensable in the petroleum sector. Its amplified surface area empowers efficient catalysis and UV absorption. This dynamic material optimizes hydrocarbon processes, shields against UV degradation, and boosts infrastructure longevity, redefining petroleum industry standards [51, 52].

In 2016, Ghafari et al. conducted a study to explore how these nanoparticles influenced the modification of rheological properties in cement paste. The amount of superplasticizer absorption increased, indicating competition between these nanoparticles and cement for polymer adsorption. Due to their specific surface area, these nanoparticles exhibited a higher absorption rate compared to cement. Furthermore, the addition of these nanoparticles led to an increase in saturation point, yield stress, and viscosity compared to raw cement paste. The increase in yield stress over time is influenced by the amount of zinc oxide nanoparticles, and higher concentrations of these nanoparticles resulted in a more rapid increase in thixotropic behavior. This substance demonstrated better fluidity preservation performance than aluminum-doped zinc oxide. Pastes containing 0.4% by weight or less showed excellent performance in preserving functionality, but their performance decreased at higher percentages [53]. According to a study by Liu et al. [39], zinc oxide has a minor effect on slurry fluidity due to its low specific surface area. Increasing the concentration of zinc oxide nanoparticles in modified mortar with 2% by weight concentration resulted in an 80% reduction in compressive strength compared to the 28-day control sample [39].

2.1.5 Nano-magnesium oxide

Nano-magnesium oxide, possessing heightened reactivity due to its nanostructure, serves as a pivotal catalyst and adsorbent in the petroleum industry. With amplified surface area, it accelerates reactions, reduces impurities, and aids pollution control, contributing significantly to refining efficiency and environmental sustainability [54, 55].

In 2018, Jafariesfad et al. introduced controlled reactivity of nano-magnesium oxide particles to manage cement shrinkage in a cement system. The reactivity of nano-magnesium oxide was regulated through thermal treatments, and cement systems were investigated using calorimetry at various temperatures. The outcomes of this study indicated that an increase in thermal treatment temperature led to the coarsening of nano-magnesium oxide and a delay in its reaction. They demonstrated that the addition of nano-magnesium oxide, during low-temperature thermal processes, to a cement system resulted in a significant reduction in setting time compared to the reference system without nano-magnesium oxide. Controlling the reactivity of nano-magnesium oxide could potentially serve as a promising approach in designing cement systems with minimal shrinkage [56].

2.1.6 Nano-titanium dioxide

Nano-titanium dioxide boasts potent catalytic prowess and photoactivity due to its expanded surface area at the nanoscale. In the petroleum industry, it plays a crucial role in refining, elevating processes like hydrocracking and desulfurization for efficient pollutant reduction and enhanced product quality. Its accelerated reactions and stability align to champion eco-conscious practices in petroleum operations [57, 58].

Liu et al.’s 2015 research indicated that the incorporation of nano-titanium dioxide led to a reduction in both compressive and flexural strength [39].

In the year 2022, Khan et al. investigated the influence of nano-titanium dioxide on class G cement. The addition of minor quantities of these nanoparticles (ranging from 0.5% to 2% by weight) was found to have a dual effect: it simultaneously enhanced compressive strength while decreasing the setting time of the cement. The compressive strength of the cement mixture increased with higher concentrations of titanium dioxide nanoparticles in the slurry, while the setting time decreased. It was also observed that the viscosity of the cement slurry increased with the addition of these nanoparticles [57].

In another study by Lee et al. [59], the effect of these nanoparticles on the properties of Portland cement was investigated. The experimental analysis conducted by employing calorimetry, chemical shrinkage, setting time, compressive strength, and surface microhardness aimed to investigate the influence of titanium dioxide nanoparticles on the initial and prolonged characteristics of cementitious materials. In this research, a segment of the cement was substituted with TiO₂. Nano-titanium dioxide accelerates the early-stage hydration process and contributes to higher degrees of hydration in Portland cement. With increasing TiO₂ content, despite the reduction in cement content due to TiO₂ substitution, the setting time decreases, indicating accelerated hydration. Comparing cement composites with TiO₂ from two different TiO₂ producers, the results demonstrate that nanoparticle size and dispersibility are crucial factors influencing the hydration rate, with smaller agglomerates, but not necessarily smaller particles, creating a more pronounced effect. Compressive strength demonstrates an upward trend with greater incorporation of TiO₂ nanoparticles, especially evident at a reduced water-to-solids ratio of 0.40. Notably, strength remains uncompromised even at a TiO₂ substitution level of up to 10% when the water-to-solids ratio is maintained at 0.60. It is important to note, however, that an increase in TiO₂ content leads to a decline in the microhardness of the composite material [59].

In 2018, Wang et al. conducted a study to explore the impact of these nanoparticles on the properties of cement under low-temperature conditions. Samples with substitutions of 1%, 2%, 3%, 4%, and 5% by weight of nanoparticles were chosen for the study at temperatures of 0°C, 5°C, 10°C, and 20°C. It was found that low temperatures delayed the cement hydration process, while titanium dioxide nanoparticles accelerated hydration and reduced setting time. The sample with 2% by weight of TiO₂ nanoparticles exhibited desirable physical and mechanical properties compared to samples without TiO₂ nanoparticles [60].

2.2 Carbon materials

2.2.1 Carbon nanotubes

Carbon nanotubes, composed of carbon atoms in a unique cylindrical lattice, boast exceptional mechanical and electrical traits. In the petroleum sector, they are pivotal for catalytic support, enhancing refining processes and aiding efficient oil extraction, thanks to their high surface area and adsorption qualities [61, 62].

In a study conducted by Santra et al. [34], the impact of carbon nanotubes was examined at a dosage of 0.1%. However, no noteworthy enhancement in the tensile strength of cement was noted at this particular concentration [34].

On the other hand, in a study by El-Gamal et al. [35], at a dosage of 0.1% carbon nanotubes, mechanical properties increased, but at a dosage of 0.15%, a reduction was observed. Additionally, based on SEM micrographs, a refined and denser microstructure was achieved by adding carbon nanotubes, leading to an improvement in the microstructural properties of the mixed slurries [35].

In 2014, De Paula et al. investigated the consequences of incorporating carbon nanotubes into cement slurries, focusing on how this addition influenced both the rheological and mechanical properties of the cement. Carbon nanotubes were directly deposited on cement clinker through chemical vapor deposition. Cement paste containing 0.1% by weight of carbon nanotubes was compared with slurries without carbon nanotubes. Lignosulfonate (0.2% by weight of cement) was used as a dispersant in all cement slurries. Compressive and tensile strength were evaluated at 48 hours and 7 days. The results show that the addition of carbon nanotubes does not alter the rheological behavior and stability of cement slurries, considering the dispersant and concentrations used. However, the presence of carbon nanotubes in cement slurries increases tensile strength by approximately 15% at 0.1% dosage of carbon nanotubes, both at 48 hours and 7 days [63].

The effect of adding multi-walled carbon nanotubes (MWCNTs) with an outer diameter of 10–20 nm and a length of 10–30 micrometers was investigated in 2020 by Rzepka et al. under high-temperature and high-pressure conditions of 60–130°C and 25–80 megapascals on Portland cement slurry CEM I 42.5R and class G oil well cement. The results demonstrated an increase in compressive strength by up to 44 megapascals, adhesion to the casing by up to 8 megapascals, and flexural strength by up to 11 megapascals [64].

In 2005, a study was undertaken by Li et al. to explore the consequences of integrating multi-walled carbon nanotubes (MWCNTs), which had undergone modification using a combination of H₂SO₄ and HNO₃, into cementitious matrix composites. Their study revealed notable improvements in the flexural strength, compressive strength, and fracture strain of the cementitious matrix composites due to the presence of nanotubes. Mercury intrusion porosimetry was employed to analyze the porosity and pore size distribution of the composites. The results indicated that the addition of carbon nanotubes contributed to a reduction in both the distribution of pore sizes and overall porosity. Fourier-transform infrared spectroscopy was used to determine the phase composition, revealing surface interactions between the carbon nanotubes and cement hydrates such as C-S-H and calcium hydroxide. These interactions resulted in a robust bond between the reinforcement and the cement matrix. Furthermore, scanning electron microscopy was utilized to analyze the mineralogy and microstructure. This analysis demonstrated that carbon nanotubes functioned as bridges, effectively connecting cracks and voids, thus facilitating charge transfer under tension. This multifaceted study highlighted the positive influence of carbon nanotubes on the mechanical properties and structure of cementitious matrix composites [65].

In 2013, Wang et al. introduced multi-walled carbon nanotubes that had been modified with anionic gum arabic into Portland cement pastes as part of a research initiative. The aim was to scrutinize their impact on flexural strength. The study delved into the flexural strength of the cement composites, revealing that the incorporation of nanotubes substantially bolstered both fracture energy and the flexural strength index of Portland cement pastes. Employing mercury intrusion porosimetry, the porosity and distribution of pore sizes within the composites were assessed, pointing towards the cement paste containing multi-walled carbon nanotubes displaying diminished porosity and more consistent pore size distribution. Scanning electron microscopy was employed to investigate the microstructure of the specimens, uncovering the role of multi-walled carbon nanotubes as bridges spanning fissures and voids. These nanotubes interweaved, forming a network adept at transmitting load during periods of stress [66].

In 2008, Cwirzen et al. conducted an investigation into the effects of incorporating multi-walled carbon nanotubes into drilling cement. They produced various compositions of cement paste samples containing these modified nanotubes using a small vacuum mixer. The mixtures adhered to water-to-binder ratios of 0.25 and 0.3. The study employed sulfate-resistant cement, and the multi-walled carbon nanotubes were introduced into the mix as an aqueous suspension, incorporating added surfactants. These surfactants fulfilled a dual role, acting as both a plasticizer for the cement paste and a dispersant for the multi-walled carbon nanotubes. To assess the mechanical properties, a series of beams were fabricated for measuring compressive and flexural strength. Microscopic analyses through scanning electron microscopy and atomic force microscopy were performed on fractured and polished samples, revealing a uniform distribution of multi-walled carbon nanotubes within the cementitious matrix. The observations from these studies indicated that the multi-walled carbon nanotubes exhibited a propensity to slip away from the matrix under tension, underscoring their relatively weak bond with the cementitious matrix [67].

In 2019, two different lightweight cement systems, foam cement and microsphere cement, were mixed with multi-walled carbon nanotubes at a concentration of 0.5% by weight by Li et al. The results indicate that the addition of carbon nanotubes to lightweight cements increases compressive, tensile, and flexural strengths, as well as the Young’s modulus, strain capacity, and workability, while reducing permeability [68].

2.2.2 Graphene nanoplatelets

Graphene nanoplatelets are two-dimensional carbon structures with remarkable properties. In the petroleum industry, they enhance drilling fluids and cement composites, improving viscosity, stability, and filtration control. This optimizes drilling processes, ensuring safer and more efficient oil and gas extraction [69, 70].

The impact of graphene nanoplatelets was investigated by Alkhamis and Imqam in 2018. The findings demonstrated that the inclusion of graphene nanoplatelets led to a 10% increase in compressive strength and a 30% increase in tensile strength [71].

2.2.3 Cellulose nanofibers

Cellulose nanofibers, derived from plant cell walls, possess impressive strength and surface area. In the petroleum industry, they serve as valuable additives in drilling fluids and cement slurries, enhancing efficiency and environmental sustainability [72, 73].

Sun et al. conducted a comprehensive investigation in 2016 on the influence of cellulose nanofibers (CNFs) on various aspects of cement, including flow, hydration, morphology, and strength. They employed an array of spectroscopic techniques, coupled with rheological modeling and power analysis. Among the models considered, the Vom-Berg model exhibited the optimal fit for the rheological data. The introduction of cellulose nanofibers led to a noticeable elevation in the yield stress of the cement slurry and an augmentation in the degree of hydration of cementitious hydrates. Furthermore, the incorporation of 0.04% CNFs resulted in the 20.7% increase in the flexural strength of hydrated cement samples. However, it was observed that an excessive amount of cellulose nanofibers in the cement slurry had an adverse impact on the mechanical properties of the hydrated drilling cement, indicating a negative effect on its overall performance [74].

2.3 Clay minerals

2.3.1 Nano-metakaoline

Nano-metakaolin, a product of kaolin clay activation, boasts high reactivity and fine particles. In the petroleum sector, it reinforces wellbore cement, preventing fluid loss and bolstering well integrity for safer and more efficient drilling [75, 76].

According to the study by El-Gamal et al. [35], cement containing nano-metakaolin exhibited better compressive strength. Additionally, based on SEM micrographs, the fine structure properties of pastes produced using nano-metakaolin were improved. Ultimately, the optimal dosage of nano-metakaolin was reported as 1% for a temperature of 90°C and 2% at 25°C [35].

2.3.2 Nano-bentonite

Nano-bentonite, a nanomaterial from clay minerals, boasts high surface area and adsorption capacity. Vital in the petroleum sector, it stabilizes wellbores, controls viscosity, and reduces fluid loss in drilling fluids, optimizing oil and gas extraction sustainably.

In 2013, Roddy et al. conducted an investigation into cement slurries containing nano-bentonite compared to cement slurries containing regular nano-bentonite. A significant decrease in cement permeability and notable mechanical enhancements were observed in the cement with nano-bentonite compared to the ordinary bentonite cement [77].

According to this section, silica nanoparticles are found as the most common additives in the drilling cement, followed by carbon nanotubes and nano-alumina. As discussed, these nanoparticles are used to improve permeability, porosity, mechanical and rheology properties of cement, so one may conclude that these properties are essential to the drilling engineers.

3. Nanohybrids and nanocomposites

In 2020, in response to subsurface challenges, an innovative elastomeric cement had been devised, integrating a specialized additive containing carbon nanotubes (CNTs) within a matrix of methyl methacrylate polymer by Mohamadian et al. This forward-looking approach not only ensures ample strength but also enhances cohesiveness. The refined rheology substantially curtails fluid loss, concurrently elevating mechanical properties and the bond strength of the cement. Significantly, this additive mitigates cement shrinkage, offering multifaceted benefits in the realm of well cementing. Of note, the synergy of polymers and carbon nanotubes within cement compositions represents an unexplored avenue, marking a departure from conventional practices [78].

In 2017, Sun et al. delved into the synergistic interplay of cellulose nanofibers and graphene nanoplatelets. The infusion of a composite blend, incorporating 0.04% cellulose nanofibers and 0.05% graphene nanoplatelets into cement slurry, yielded a remarkable 25% increase in flexural strength [79].

In 2015, Polat et al. scrutinized the effects of varying ratios of expanded perlite, micro- and nano-sized magnesium oxides, calcium oxide, and nano-rice smectite on autogenous shrinkage within cementitious matrices. The most noteworthy reduction in shrinkage was witnessed in the mixture containing 7.5% calcium oxide and nano-magnesium oxide, yielding an impressive 80% decrease in autogenous shrinkage over a 28-day timeframe. Notably, the impact of nano-calcium oxide on shrinkage was marginal [80].

In 2019, Li et al. harnessed the potential of nano-silica reinforced with fibers to bolster cement properties. The mechanical attributes of the fortified cementitious structure outperformed those of the pristine counterpart. Importantly, compressive and tensile strengths of the oil well cementitious material recorded increments of 25% and 26%, respectively, in comparison to the unalloyed oil well cement sample. However, this enhancement was offset by a 29% reduction in elastic modulus [81].

Ghafari et al. investigated the ramifications of aluminum-doped zinc oxide nanoparticles on cement slurry, drawing a comparison with their undoped zinc oxide counterparts in 2016. The integration of nanoparticles yielded significant superplasticizer (SP) adsorption escalation, while the nanoparticle-infused cement paste demonstrated an accelerated absorption rate relative to the pristine cement paste. Remarkably, aluminum-doped zinc oxide nanoparticles exhibited a higher absorption rate than their undoped zinc oxide counterparts, potentially attributed to an augmented zeta potential effect at the particle interface. The increase in yield stress over time was influenced by the concentration of aluminum-doped zinc oxide nanoparticles, with higher nanoparticle content leading to a more pronounced enhancement in thixotropic behavior. This material, conducive to cement retardation, closely mirrored the performance of undoped zinc oxide nanoparticles. Encouragingly, similar to the behavior of zinc oxide nanoparticles, cement pastes containing 0.4% by weight or less demonstrated exceptional efficacy in cement retardation, although this efficacy diminished at higher concentrations [53].

A schematic of nanohybrids and how they reduce water content and increase surface area that cause improvement in cement properties is presented in Figure 1.

Figure 1.

A schematic of how nanohybrids reduce water content and increase surface area.

4. Conclusions

Nanomaterials have been recognized as influential factors in improving and enhancing the properties of drilling cement in recent years. This review article comprehensively examines research and scientific studies related to the effect of nanomaterials on the quality of drilling cement, evaluating and analyzing the diverse results obtained in this field. One of the main findings of this article is the positive impact of nanoparticles on the mechanical properties of drilling cement. The use of nanomaterials increases compressive strength and elastic modulus of the cement. This enhancement in mechanical properties significantly improves the performance of cement in drilling and oil production conditions. Furthermore, nanoparticles can act as catalytic agents in cement chemical processes. This leads to accelerating formation processes and improving cement setting. Additionally, adding nanomaterials to drilling cement can assist in regulating setting time and strength development. However, observations indicate that the outcomes of using nanomaterials in drilling cement are dependent on various factors such as the type of nanomaterial, nanomaterial dosage, environmental conditions, and other factors. In some cases, adding nanomaterials may not improve the quality of drilling cement and may even lead to undesirable changes in cement properties. On the other hand, extensive research has not been conducted on a wide range of nanomaterials. Some improved properties achieved by nanoparticles, such as reduced shrinkage and sulfate resistance, have been discussed in limited studies, suggesting that the effects of nanomaterials should be further investigated across a broader spectrum of cement properties. Furthermore, very limited research has been carried out on the synergistic effects of nanoparticles. Considering the potential of this approach in enhancing cement properties, more extensive research is needed in this technique. In general, the use of nanomaterials as a novel approach to improving the quality of drilling cement is feasible, but it requires further research and operational experiments to determine the optimal conditions for nanomaterial use in various drilling environments. Therefore, more research is recommended in the selection of the most suitable nanomaterials, the amount of addition to cement, and the optimal drilling conditions.

Conflict of interest

The authors declare no conflict of interest.