Water-based Drilling Fluids Research Articles

Synthesis and Mechanism Study of an Environmental Additive Used in Water-Based Drilling Fluids from Bovine Bone Glue

At present, animal bone glue has been widely used in industry, but there are no relevant research reports on its application in the petroleum industry. In this paper, the rheological properties, inhibition, filtration, and temperature resistance performance of modified bone glue (Mbg) were evaluated in water-based drilling fluids, and the results showed that Mbg can significantly affect the performance of water-based muds with minimal dosage, and temperature resistance of Mbg could reach up to 130 °C. The inhibition mechanism of Mbg in drilling fluids was investigated by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), zeta potential, thermogravimetric analysis (TGA), and scanning electron microscope (SEM). Results revealed that when 2% Mbg was added, a three-dimensional network structure was formed in an aqueous solution, which reduced the water content from 4.83% to 4.23%. FT-IR analysis showed that Mbg strongly adsorbed onto clay through hydrogen bonding, which reduced the clay particles in based muds from 1.251 µm to 0.789 µm and effectively controlled the filtration loss of the drilling fluids.

Study on the Effectiveness of Okra as an Environmentally Friendly and Economical Lubricant for Drilling Fluid

With the gradual improvement and implementation of unconventional wells drilling and environmental regulations, there is an urgent need for high-performance and more environmentally friendly lubricants for water-based drilling fluids (WD). Developing green oilfield chemicals from natural products is a shortcut. In this work, Abelmoschus esculentus (L.) Moench/okra has been studied as the lubricant in WD. The green drilling fluid lubricant developed demonstrates excellent lubrication performance, as well as good filtration loss reduction and inhibition of bentonite hydration expansion. The results show that with the addition of 2.5% okra slurry to water-based drilling fluid, the coefficient of friction decreased by 51.68%, the apparent viscosity (AV) increased by 51.32%, the plastic viscosity (PV) increased by 42.99%, and the fluid loss decreased by 39.88%. Moreover, through TGA, SEM, FT-IR, particle distribution tests, and contact angle tests, the lubrication mechanism of okra slurry was discussed. Finally, the economic feasibility of using okra as an environmentally friendly lubricant for drilling fluids was analyzed. This work combines agricultural products with industrial production, which not only solves industrial problems but also enhances the added value of agricultural products, providing a reference for the coordinated development of industry and agriculture.

Influence of Salt and Temperature on the Rheological and Filtration Properties of Cellulose Nanofiber/Bentonite Water-Based Drilling Fluids

Influence of Salt and Temperature on the Rheological and Filtration Properties of Cellulose Nanofiber/Bentonite Water-Based Drilling Fluids

Development and performance evaluation of a mechanically triggered release microcapsule based on in-situ polymerization for lost circulation control

Lost circulation is a critical technical challenge in the drilling and production process of underground oil and gas energy. In this study, a mechanically triggered release microcapsule for lost circulation control was designed and prepared with an in-situ polymerization using melamine, urea, formaldehyde, and diglycidyl ether of bisphenol A (healing agent) as raw materials. The structure and properties of the microcapsule were characterized by different techniques. The results show that the healing agent was successfully encapsulated by the resin shell, the median particle size (D50) of the microcapsules is 120.3 μm, and the thermal stability is excellent. The compatibility experiments show that the surface wettability and shear stability of the microcapsules are good in water-based drilling fluid. The compressive strength test reveals that the healing agent in the microcapsule is released and filled in the gap of the plugging zone under the contact pressure. The concentration of microcapsules and the size distribution of rigid particles are critical for the in-situ reinforcement effect. In addition, the fracture plugging performance of the microcapsule was studied. The results show that the pressure-bearing capacity of the plugging zone increases as the irregularity of the fracture surface increases. These findings indicate the microencapsulated healing agent is an effective lost circulation material (LCM), and provide a new technical idea for lost circulation control.

Carbon microspheres prepared from soluble starch hydrothermal carbonization for extending thermal stability of water-based drilling fluid

This study employed hydrothermal carbon microspheres (HCMs) as high-temperature stabilizers in drilling fluids. The HCMs were synthesized through a green hydrothermal carbonization method, using soluble starch as the precursor. The impact of HCMs on the thermal stability of xanthan, polyanionic cellulose and synthetic polymer solutions was assessed by comparing their rheological changes before and after thermal aging. The rheology and filtration properties of a polymer-based drilling fluid in the presence of HCMs were recorded before and after dynamic thermal aging at various temperatures for 16 h and static thermal aging at 200 °C for 96 h. The results demonstrated that HCMs effectively maintained stable rheology and low filtration loss following dynamic hot rolling at various temperatures and prolonged static thermal aging, surpassing the performance of conventional Na2SO3 and nano-SiO2 stabilizers. Mechanistic studies, including dissolved oxygen measurements, free radical detection, and cryo-scanning electron microscopy observations, revealed that HCMs can consume dissolved oxygen, scavenge free radicals, and physically crosslink polymers. This process prevents polymer thermo-oxidative degradation and ensures the stability of the drilling fluid. HCMs are novel, stable, sustainable, and highly effective high-temperature stabilizers for water-based drilling fluids. This study introduces a new application of biomass-derived hydrothermal carbonaceous materials for high-temperature drilling.

Experimental and numerical study of the rheological characteristics and flow law of water-based drilling fluids in high-temperature and high-pressure wellbores

Experimental and numerical study of the rheological characteristics and flow law of water-based drilling fluids in high-temperature and high-pressure wellbores

High-temperature tribological behaviors of polycrystalline diamond under water-based drilling fluid environments

High-temperature tribological behaviors of polycrystalline diamond under water-based drilling fluid environments

Co-Gelatinization Modification of Iodine–Starch and Its Performance in Drilling Fluid

Modified starch is used as a drilling fluid treatment agent in oilfields. During the drilling process, modified starch plays a vital role in the drilling fluid system, but its poor temperature resistance limits its application in oilfields. Therefore, this paper studied the performance of several starches in water-based drilling fluids through co-gelatinization modification; studied the effectiveness of several modifiers in gelatinized starch drilling fluids, combined with flow modification performance tests, bentonite linear expansion rate, salt resistance, and other experimental methods to complete the screening of the best modified starch; and systematically compared the temperature resistance, inhibition, compatibility, and salt resistance before and after gelatinization. The possible mechanism of action of modified starch treatment was analyzed and tested by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), laser particle size analyzer and scanning electron microscopy (SEM). The results showed that the decomposition temperatures of cassava starch (TS), potato starch (PS), and corn starch (CS) were different, and the decomposition temperature of cassava starch (TS) was the highest, at 150 °C. At this temperature, the optimal dosage of gelatinized TS is 2.5%, the maximum shear force is 2.25 Pa, and the filtration loss is only 12.6 mL. TS has obvious performance advantages over other starches. After co-gelatinization with 1.0% iodine and 2.5% TS at 140 °C, it has a good viscosity reduction and filtration loss effect, and the filtration loss is only 5.2 mL, which is 31.6% lower than that of untreated TS drilling fluid. The linear expansion rate at 120 min is 10.85%, indicating that it has a strong inhibitory effect on the hydration and dispersion of bentonite. In addition, iodine cassava starch (ITS) has good compatibility in drilling-fluid formulations and shows good salt resistance when mixed with different concentrations of KCl. The results of this study can be used to improve the temperature resistance of filtration agents and facilitate related research.

Thermosensitive polymer/nanosilica hybrid as a multifunctional additive in water-based drilling fluid: Rheologicalproperties and lubrication performance as well as filtration loss reduction capacity

In previous studies, for obtaining a flat rheological drilling fluid, binary and ternary thermosensitive silica (SiO2) nanohybrids as rheological modifiers were synthesized using N-isopropylacrylamide with a thermal association temperatureof 32–33 °C as the thermosensitive monomer [J. Petrol. Sci. Eng. 219 (2022), 111096; Geoenergy Science and Engineering 228 (2023), 211934]. However, the as-synthesized SiO2 nanohybrids exhibited limited performance and low thermal transition temperature. Thus surface initiated atom transfer radical polymerization was utilized to graft hydrophilic poly(ethylene glycol) methyl ether methacrylate (PEGMA) onto SiO2 surface to obtain PEGMA/SiO2 nanohybrids with an elevated thermal association temperature of 75 °C. The morphology and structure of the as-synthesized PEGMA/SiO2nanohybrid were characterized by infrared spectroscopy and transmission electron microscopy; and its effects as a thermosensitive multifunctional additive on the rheological properties and lubrication performance as well as filtration loss reduction capacity of a water-based drilling fluid were investigated. Results indicate that the drilling fluids with 1.0% PEGMA/SiO2 nanohybrids exhibited obvious thermal thickening behavior in the temperature range of 70–80 °C; at low temperatures, however, they had a significant viscosity reduction effect therein. At room temperature, the apparent viscosity and plastic viscosity were reduced by 68% and 50%, respectively. Besides, due to the tightly packed plugging layer formed by PEGMA/SiO2 nanohybrids and bentonite, the filtration loss of the drilling fluids containing 1.0% PEGMA/SiO2 nanohybrid was reduced by 37% as compared with that of the base slurry; and the lubrication coefficient was decreased by up to 50%. Moreover, the high-temperature aging process promoted the intermolecular interactions of the nanohybrids and their interaction with bentonite flakes, thereby further improving the rheological behavior, filtration reduction ability, and lubricity of the drilling fluids. The as-synthesized thermosensitive PEGMA/SiO2 nanohybrids with excellent multifunctionality could find promising application in water-based drilling fluids.

Gas kick dynamic circulation in MPD operations with water based drilling fluid: Maximum casing pressure modeling and validation

The use of water-based drilling fluids enables the rapid detection of a gas influx by pit gain monitoring due to the low solubility of gases in the aqueous medium. Moreover, as the influx remains as a free gas, it undergoes a process of expansion the further it rises through the well, changing the pressure profiles and producing a pressure peak when it reaches the surface. Therefore, the gas influx must be controlled appropriately. Otherwise, the maximum pressure experienced during the kick circulation may exceed the safety limits of surface equipment, placing the operation and the rig crew in a hazardous situation. The Managed Pressure Drilling (MPD) technique allows for a more precise detection and control of the influx while retaining the ability to circulate dynamically small volumes of gas kick through the riser, minimizing the risks involved and the non-productive time (NPT). However, the decision of when to apply dynamic or conventional circulation techniques must be considered carefully, taking into account factors such as predictions of pressure peaks, as well as intensity and volume of the kick. In this way, it is paramount that the maximum pressure during the circulation be estimated before the operation begins to ensure that the decision is made correctly. This paper presents the results of a gas kick circulation simulator specifically developed to predict pressure peaks. This simulator uses a mathematical model based on algebraic equations whose solution requires low computational effort and, therefore, regarding gas kick incidents, is an interesting tool that can aid in guiding decision-making. The results of pressure peaks were successfully validated by employing literature data, experimental drilling setup runs and simulations performed in a commercial software largely consolidated in the petroleum industry: Drillbench.

A Novel Technique in Determining Mud Cake Permeability in SiO2 Nanoparticles and KCl Salt Water Based Drilling Fluid using Deep Learning Algorithm

The permeability of the mud cake formed at the formation-wellbore interface is an important factor in the designing of water-based drilling fluids. This study presents a novel approach to utilizing experimental thixotropic and rheological parameters of polymeric water-based drilling fluids having varying concentrations of SiO2 nanoparticles and KCl salt. A fully connected feed-forward multi-layered neural network, more commonly known as a Multilayer Perceptron (MLP) was developed to predict the mud cake permeability using input parameters such as SiO2 & KCl concentration, differential pressure, temperature, mud cake thickness, API LPLT and HPHT filter loss volume and spurt loss volume. The results suggested that the developed Multilayer Perceptron model effectively determined the mud cake permeability based on the input parameters of the WBDF mentioned above. The model converged on the global minima, minimizing the loss function using the Gradient descent algorithm. A higher Coefficient of Determination (R2) value i.e., 0.8781, and a lesser Root Mean Square Error (RMSE) value i.e., 0.04378 indicates the higher accuracy of the model. Pearson’s Coefficient of Correlation obtained via the heatmap indicates that mud cake permeability is strongly influenced by the differential pressure followed by filter loss volume, spurt loss volume, mud cake thickness, and temperature. Previous similar studies have focused on using machine learning algorithms, this study utilized a robust deep learning algorithm i.e., Multilayer Perceptron (MLP) neural network to simultaneously model the combined effects of SiO2 nanoparticles and KCl salt concentrations on mud cake permeability, offering an unprecedented level of accuracy in predicting key WBDF performance parameters

Effect of natural Frankincense extract on clay swelling inhibition in water-based drilling fluids

The effect of Frankincense extract (FE) as an environmentally friendly additive on the swelling inhibition of sodium bentonite in aqueous solution is presented. The inhibition potential of FE was assessed through sodium bentonite (Na-BT) sedimentation tests, rheological investigations, and immersion test. The results indicated that the inhibition property of FE is dependent on its concentration and its performance at 5 wt.% is comparable to potassium chloride at 3 wt.% as a commonly used inhibitor. FE increased the loading of Na-BT in deionized water (DI water) from 7.5 to 17.5 wt.% at 5 wt.% FE concentration. Furthermore, FE reduced the dispersion of Na-BT, resulting in an increase in Na-BT particle size from 1034 nm in DI water to 4294 nm at a 1 wt.% FE concentration. X-ray diffraction test and thermal gravimetric analysis revealed that FE can insert itself into the interlayer space of clay minerals. FE reduced the zeta potential of Na-BT from −24.3 mV in DI water to −5.21 mV at a 5 wt.% FE concentration. Additionally, the compatibility test proved that FE could also decrease the drilling fluid filtration and act as a fluid loss control agent.

Synthesis and Evaluation of High-Temperature Resistant Polymer Plugging Agent for Water-Based Drilling Fluids.

As the exploration and development of deep wells have emerged as a key option to extract more oil and gas resources trapped underneath, high-temperature formations impose stringent requirements on the thermal stability of plugging agents used in water-based drilling fluids. In this work, β-cyclodextrin, with its unique conical toroidal rigid stable structure and internal hydrophobic and external hydrophilic special adsorption capacity, was first grafted with maleic anhydride to prepare a silicone polymer and then copolymerized with dimethyldiallylammonium chloride (DMDAAC) in the presence of coupling agent vinyltriethoxysilane (A151) and cross-linking divinylbenzene (DVD) to finally obtain a high-temperature resistant plugging agent (AMMD). Subsequently, the molecular structure was evidenced and the performance of AMMD was examined in the polysulfonate-base fluid via a series of tests including high-temperature high-pressure filtration loss, sand tray plugging, and drilling fluid displacement, and the results were compared with the counterpart Soltex under the same conditions. The optimal synthesis conditions for the plugging agent were found as total monomer concentration of 25%, initiator mass fraction of 1% (based on the mass of monomers), monomer feed ratio of m (DVD):m(A151):m(DMDAAC):m(MD) of 15:3:2:15, pH value of 10, reaction temperature of 75 °C, and reaction time of 4 h. FT-IR spectra indicated that the monomers used to prepare AMMD were successfully involved in the reaction for the design of the plugging agent structure. TGA showed that AMMD has a total weight loss of about 35.98% in the range of 284 to 453 °C. Moreover, the addition of 3%AMMD into the base fluid produced a 4.38-fold and 3.8-fold filtration loss control over 60 min at 200 °C using 400 and 800 mD sand trays, respectively, which were comparatively higher than the commercially available Soltex (ca. 3.72-fold and 3.14-fold, respectively, using 400 and 800 mD). This then contributed to AMMD's superior plugging performance in drilling fluid based on the drilling fluid displacement experiment, implying that AMMD could find potential use as a plugging agent in polysulfonate drilling fluid under severe geothermal conditions.

Machine-Learning Predictive Model for Semiautomated Monitoring of Solid Content in Water-Based Drilling Fluids

Machine-Learning Predictive Model for Semiautomated Monitoring of Solid Content in Water-Based Drilling Fluids

An experimental study to improve filtration properties of water-based drilling fluids using rambutan as green additive

An experimental study to improve filtration properties of water-based drilling fluids using rambutan as green additive

Developing a machine learning-based methodology for optimal hyperparameter determination—A mathematical modeling of high-pressure and high-temperature drilling fluid behavior

Drilling fluids exhibit complex rheological behavior due to a non-linear response to shear rate variations and high sensitivity to changes in temperature, time, and pressure conditions. The prediction of drilling fluid rheological behavior is crucial for the success of oil well drilling, and it directly impacts the fluid's performance. The dataset used in this study was obtained from extensive rheometric tests of water-based and olefin-based drilling fluids in steady-state flow curves. The optimal hyperparameters were guided by performance metrics and compared with alternative models such as Power-law and Herschel-Bulkley rheological models. Different configurations with different hidden layers, using neuron sequences of 16, 32, and 64, learning rates of 0.001 and 0.01, and the ReLU activation function were used to improve the model's performance. Additionally, the paper delved into the impact of the number of training epochs on the accuracy of shear stress predictions. Finding this equilibrium was identified as a crucial factor in achieving precise results. The neural network model demonstrated remarkable accuracy when using the ML-C3 configuration, with MAE values of 0.535 and R2 of 0.987 in predicting the steady-state flow curves of drilling fluids, establishing itself as a powerful tool for forecasting the rheological behavior of these fluids under diverse operational conditions. The present research significantly contributes to the field of drilling fluid rheology and provides valuable insights for optimizing drilling operations in HPHT environments.

An investigation on tribological behavior of TC bearing materials: Effect of nano-SiO2 concentrations under different loads in the drilling fluid environment

Both Nano-SiO2 (Silicon dioxide nanoparticles) additive concentration and axial load have profound effects on the friction and wear of Tungsten Carbide bearings in the drilling fluid environment. However, the coordinated role of them remains unknown. In this work, the effects of Nano-SiO2 concentrations and axial loads on the tribological behavior of bearing materials were investigated simultaneously. Results show that the water-based drilling fluid containing Nano-SiO2 exhibits more excellent lubrication properties under 200 N as compared with 70 N, and the optimal concentration of Nano-SiO2 additive is 1.0 wt% under all loads. High axial loads are conducive to improve the lubrication performance, and the lubrication mechanisms of Nano-SiO2 under different loads in water-based drilling fluid are the multitudinousness of synergistic effects, including rolling bearing, polishing, shielding, and self-healing effect, which all manifested there is an remarkable load dependence of Nano-SiO2 particles.

Evaluation of shell powders of bush mango and hamburger bean as eco-friendly fluid loss control additives in water-based drilling mud

The use of agro-based additives in drilling mud to reduce fluid loss and improve the rheological properties of mud has gained enormous attention owing to its biodegradability and low cost. This study evaluates the effects of shell powders of hamburger bean and bush mango as eco-friendly and cheap filtration control additives in water-based mud. Samples were formulated with different concentrations (5 g, 10 g, 15 g, and 20 g) of the shell powders to determine their effects on the filtration and rheological properties of the mud. From the results, both hamburger beans and bush mango shell powders improved the rheological properties of the fluid. Meanwhile, only 15 and 20 g of Bush mango shell powders reduce fluid loss by 10.5 and 13.2%, respectively. Similarly, the addition of 5 g, 10 g, 15 g, and 20 g of hamburger bean shell powders reduced fluid loss by 1.4, 8.82, 14.71, and 20.6%, respectively. Both Bush Mango and Hamburger Beans shell powders based mud produced cake thickness between 1.2 and 1.8 mm. The research demonstrates that Hamburger Beans shell powders provides a progressive decrease in filtration rate as the content increases, and it stand as a cheap and eco-friendly alternative additive for the enhancement of rheological and filtration properties in water-based drilling fluids.

Preparation of molybdenum disulfide/bentonite nanohybrid and its tribological properties as lubricant for water-based drilling fluids

In recent years, with the increase in energy demand and gradual scarcity of medium and shallow oil and gas resources, oil and gas exploration has shifted to special wells such as deep wells, ultra-deep wells, and extended reach wells. These complex wellbore structures inevitably increase the torque and friction between the casing and the drill pipe during drilling, which aggravates friction and wear, and leads to accidents such as drill sticking and drill breakage in severe cases. In this study, molybdenum disulfide/bentonite (MoS2/Bent) nanohybrids as drilling fluid lubricant were synthesized by hydrothermal method using sodium molybdate (Na2MoO4) and thiourea (CH4N2S) as raw materials and bentonite as carrier. The as-synthesized MoS2/Bent nanohybrid was characterized by X-ray powder diffractometer, transmission electron microscopy, Fourier transform infrared spectroscopy, and the high temperature resistance and tribological properties of MoS2/Bent nanohybrid were evaluated in base slurry. The results show that the friction coefficient of MoS2/Bent nanohybrid drilling fluid before aging is reduced by 74 % and the wear rate is reduced by 97 % compared with the base slurry. After high-temperature aging at 240 °C, the friction coefficient is reduced by 77 % and the wear rate is reduced by 90 %. The excellent friction reducing and antiwear performance is attributed to the formation of low shear strength MoS2 deposition film and oxide tribofilm on the surface of the friction pair during the rubbing process.

Hybrid Machine-Learning Model for Accurate Prediction of Filtration Volume in Water-Based Drilling Fluids

Accurately predicting the filtration volume (FV) in drilling fluid (DF) is crucial for avoiding drilling problems such as a stuck pipe and minimizing DF impacts on formations during drilling. Traditional FV measurement relies on human-centric experimental evaluation, which is time-consuming. Recently, machine learning (ML) proved itself as a promising approach for FV prediction. However, existing ML methods require time-consuming input variables, hindering the semi-real-time monitoring of the FV. Therefore, employing radial basis function neural network (RBFNN) and multilayer extreme learning machine (MELM) algorithms integrated with the growth optimizer (GO), predictive hybrid ML (HML) models are developed to reliably predict the FV using only two easy-to-measure input variables: drilling fluid density (FD) and Marsh funnel viscosity (MFV). A 1260-record dataset from seventeen wells drilled in two oil and gas fields (Iran) was used to evaluate the models. Results showed the superior performance of the RBFNN-GO model, achieving a root-mean-square error (RMSE) of 0.6396 mL. Overfitting index (OFI), score, dependency, and Shapley additive explanations (SHAP) analysis confirmed the superior FV prediction performance of the RBFNN-GO model. In addition, the low RMSE (0.3227 mL) of the RBFNN-NGO model on unseen data from a different well within the studied fields confirmed the strong generalizability of this rapid and novel FV prediction method.