Alternate Method of Estimating Nigerian Hydrocarbon Reserves.

Reserves estimation of most oil fields is often performed through the Material Balance and Volumetric methods. Alternatively, a simple Estimation Model and Least Squares Regression may be useful or appropriate. This model used alongside with Linear Regression Analysis in this study gives improved estimates of the fields considered, hence can, be used in other Nigerian Fields with recent production history

Evaluation of Formation Damage and Assessment of Well Productivity of Oredo Field, Edo State, Nigeria

Formation damage canincurconsiderable cost for remediation and deferred production. Thorough understanding of the formation damage mechanisms, stringent measures for its control and prevention, and effective and efficient treatments are the keys for optimum production strategies for oil and gas fields. WELL 4X was investigated in this study to properly diagnosed and evaluate productivity in OREDO FIELD and Bottom Hole Pressure survey was used from Bottom Hole Pressure analysis in addition to the information of the well production history and reservoir data available to determine and assess the extent of the formation damage in the well. The WELL 4X was stimulated using Acid Foam Diversion Techniques to enhance reservoir productivity and increase economic operations. The stimulation job done on the well showed a peak increase of production from 850 bbl/day to 3200 b/d before it declined to 2150 bbl/day, and finally maintained an average stabilized rate of 2000 bbl/day. It has to be established that the treatment method on WELL 4X using Acid Foam Diversion Techniques and the Bottom Hole Pressure survey conducted on the WELL 4X in OREDO FIELD is found to be efficient in the determination and evaluation of formation damage

Performance evaluation of nanosilica derived from agro-waste as lost circulation agent in water-based mud

Seepage or loss of the mix-water from the drilling muds into the porous and permeable formations is a common problem during drilling operation. The drilling mud design requires a good knowledge of sealing integrity and all the factors influencing the mud to bridge through fractures or pore throat of exposed rocks. Loss circulation materials (LCMs) are commonly introduced into the drilling mud to prevent or minimize filtrate loss. This study investigates silica nanoparticle (SNP) derived from rice husk (RH) termed RH-SNP using the wet-milling method as an LCM in water-based mud (WBM). The impact of the RH-SNP in the enhancement of rheology and filtrate loss control properties of WBM was studied. Subsequently, the sealing integrity of the RH-SNP in a 1 mm and 2 mm simulated fracture for 7 min was determined using a stainless-steel slotted filter disk. The performance of the developed RH-SNP was compared with the widely applied nutshell. The synthesized RH-SNP at amount of 2.0 wt% significantly enhanced the yield point and plastic viscosity of the WBM by 75% and 386%, respectively, and minimized the fluid loss of the WBM by 47% at 80 °F. The enhancement is due to the particles ability to spread and interact efficiently with the WBM. With the use of 1 mm and 2 mm simulated fracture for 7 min, the mud loss volume of the base mud reduced by 50%, 66.7%, 86%, and 90% (for 1 mm) and 40%, 65.7%, 77.1%, and 80% (for 2 mm) with the inclusion of 0.5 wt%, 1.0 wt%, 1.5 wt%, and 2.0 wt% of RH-SNP, respectively. Overall, the results showed that RH-SNP enhanced the seal integrity of the drilling mud and was more resistant to deformation compared to the nutshell. The findings of this study can help for better understanding of the application of RH-SNP as a loss circulation agent owing to its superior ability to seal fractured formation compared with the often used nutshell

Amphipathic anionic surfactant modified hydrophilic polyethylene glycol-nanosilica composite as effective viscosifier and filtration control agent for water-based drilling muds

Highly stabilized and dispersible composites of polyethylene glycol and silica nanoparticle in aqueous drilling mud can provide desirable rheological and filtration properties for drilling jobs. Therefore, high-quality hydrophilic polyethylene glycol-nanosilica composite modified by amphipathic anionic sodium dodecyl sulfate (PEG-SiO2 NC-SDS) to improve the rheological and filtration properties of water-based muds (WBMs) was submitted. Test of zeta potential, functional groups, morphology, elemental composition, and temperature stability together with rheology and filtration tests were undertaken to assess the wide-ranging mud properties of the SDS modified PEG-SiO2 NC drilling muds. Zeta potential, FTIR, FESEM, EDX, and TGA results indicate that the SDS modified PEG-SiO2 NC was effectively formed and modified, it embodies exceptional thermal stability and is efficiently dispersed. The SDS modified PEG-SiO2 NC has a narrow size distribution range between 82 nm and 410 nm, and a specific surface area of 41.4 m2/g that is sufficiently high for particle-molecule interactions. Its rheological variables are notably shear-thinning and did not undergo notable fluctuation. The filtrate loss of 1.5 g SDS bearing PEG-SiO2 NC at 78 °F and 250 °F was only 5.4 ml and 9.6 ml, against 10.2 ml and 20.5 ml of the WBMs, respectively. High dispersion stability and high thermal stability aided its excellent viscosity and filtration control performance. Moreover, optimum rheological properties for the SDS modified PEG-SiO2 NC drilling muds with Bingham plastic and Ostwald-de-Waele models occurred with mud composition CD3 (CD3 = 1.5 g SDS modified PEG-SiO2 NC + WBM). Thus, this study can help to understand the applications of this nanocomposite as a potential viscosifier and filtrate loss control material for WBMs

Polymer nanocomposites application in drilling fluids: A review

Indubitably, drilling fluid is the most crucial component of drilling operations. With the current exploration of hydrocarbons in deep water horizons, unconventional formations, and anticipated production from the arctic regions, there is a need to improve the properties of existing drilling fluids for harsh conditions. Recently, the synergic combination of polymer and nanoparticle (polymer nanocomposite) has gained prodigious attention for application as a drilling fluid additive due to its sterling and fascinating properties. Herein, the application of polymer nanocomposite (PNC) as an additive in drilling fluids has been reviewed. The survey of the literature shows that PNC significantly improved the rheological, filtration, and shale swelling inhibition properties of drilling fluids. Nonetheless, accurate modelling of its behaviour remains elusive. The mechanism of the improved efficiency of PNC as a drilling fluid additive was elucidated. Finally, the gaps in the research were highlighted, and recommendations for future studies were outlined. Overall, drilling fluids containing PNC exhibited comparably higher efficiency and immense potential to overcome severe wellbore problems encountered with conventional drilling fluids

Effect of salinity on hydroxyapatite nanoparticles flooding in enhanced oil Recovery : A mechanistic study

Fluid-fluid interactions can affect any enhanced oil recovery (EOR) method, including nanofluid (NF) brine-water flooding. Flooding with NFs changes wettability and lowers oil-water interfacial tension (IFT). Preparation and modification affect the nanoparticle (NP) performance. Hydroxyapatite (HAP) NPs in EOR are yet to be properly verified. HAP was synthesized in this study using co-precipitation and in situ surface functionalization with sodium dodecyl sulfate in order to investigate its impact on EOR processes at high temperatures and different salinities. The following techniques were employed, in that sequence, to verify its synthesis: transmission electron microscopy, zeta potential, thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray diffraction, particle size analysis, and energy-dispersive X-ray spectra. The outcomes showed the production of HAP, with the particles being evenly dispersed and stable in aqueous solution. The particles' surface charge increased from -5 to -27 mV when the pH was changed from 1 to 13. The HAP NFs at 0.1 wt % altered the wettability of sandstone core plugs from oil-wet at 111.7 to water-wet at 9.0 contact angles at salinity ranges of 5000 ppm to 30,000 ppm. Additionally, the IFT was reduced to 3 mN/m HAP with an incremental oil recovery of 17.9% of the initial oil in place. The HAP NF thus demonstrated excellent effectiveness in EOR through IFT reduction, wettability change, and oil displacement in both low and high salinity conditions

Rheological and filtration control performance of water-based drilling muds at different temperatures and salt contaminants using surfactant-assisted novel nanohydroxyapatite

Today, the high-performance rheological and filtration properties of nanosized particles (NPs) in water-based muds (WBMs) are continuously reported. Nevertheless, NP's properties performance at different temperatures and salt environments, specifically the salt-screening process, needs additional knowledge. Hence, this study developed a WBM system using sodium dodecyl sulfate (SDS)-assisted nanohydroxyapatite (Nano-HAp) for different temperatures and salt contaminants. The impacts of the newly-produced Nano-HAp on the density, pH, rheology, and filtration characteristics of WBM at 298 K and 353 K were examined. The effects of salt cations (Ca2+/Na+) on a bentonite-based suspension (BN-WBM) at 298 K and 393 K and SDS-aided Nano-HAp as a salt-tolerant ingredient in drilling muds were also examined. The Herschel-Buckley and Power law models best described SDS-aided Nano-HAp drilling mud's rheology at 298 K and 353 K, respectively. Nano-HAp improved the rheological and filtration capabilities in salt and water solutions at 298 K, 353 K, and 393 K, making it a perfect field additive. 1.0 g of SDS-aided Nano-HAp is recommended, and it is thermally very stable, according to the thermal gravimetric analysis findings. It increased the viscosity performance by 78.6% at 298 K and by 79.2% at 353 K, provided desirable shear stress between 1.0 and 1000 s−1 shear rates, and decreased the fluid loss by 31.8% (≤ 8 mL) at 298 K and 25% (≤ 11 mL) at 353 K. In BN-WBM, it decreased the viscosity of the BN-salt solution from a 35-fold increase to less than a 5-fold increase and made the BN-based suspension less salt-reliant. It operated by attaching to the BN platelets' positive edge and negative face surfaces, shielding Ca2+/Na+ cations from the BN's ion-susceptible regions to decrease the viscosity and filtration of the BN-based suspension. This study demonstrates the possible use of Nano-HAp particles as effective filtration and rheological control additives in WBMs. It further demonstrates that Nano-HAp was appropriate for enhancing the drilling performance of BN-WBMs while increasing their resistance to salt cation contamination

Experimental investigation of the effects of silica nanoparticle on hole cleaning efficiency of water-based drilling mud

Effective cuttings transports and hole cleaning is crucial for obtaining an efficient drilling operation. Recently, the use of nanotechnology have been exploited to improve rheological and filtration properties of water-based mud. Herein, water-based mud (WBM) was formulated with nanosilica to enhance cuttings and solid particles transports from the wellbore to the surface. Different weight percent concentrations of nanosilica (0.001–1.5 wt%) at three different flow rates in litres/seconds (0.4, 0.6 and 1.0) and cuttings sizes (small, medium and large) were used to investigate the formulated water-based mud lifting capacity of the drilled cuttings. Experimental results show that addition of the nanosilica concentrations to the WBM enhances the viscosity, thereby increasing the muds carrying and circulating capacity. Moreover, nanosilica water-based mud (n-WBM) displays improved mud stability with high propensity to prevent intrusion of formation fluids. The effect of cuttings size on the wellbore cleaning is minimal. The large cuttings size shows a lower degree of cuttings transportation compared with the small and medium cutting size. Accordingly, the small cuttings size has higher cuttings recovery to the surface. Finally, though increase in flow rate leads to more cuttings recovery, there is every tendency that much fluid flow rate will cause an increase in frictional pressure losses and equivalent circulating density, high pump pressure requirement and potential hole erosion

Synergistic application of aluminium oxide nanoparticles and oilfield polyacrylamide for enhanced oil recovery

Due to the inherent limitation of oilfield polyacrylamide in reservoir temperature and salinity, nanoparticles (NPs) have been extensively studied for their application in enhanced oil recovery (EOR) because of their unique properties and availability in large quantities. Recent trend in nanotechnology involves incorporating NPs as additive with polymer to form novel materials termed polymeric nanofluids (PNF's) for EOR. However, previous studies have investigated and focussed more on the suitability of silica (SiO2) polymeric nanofluids. In this work, the potential application of metal oxide polymeric nanofluid for EOR was explored and evaluated. Aqueous HPAM-based Al2O3 PNF's were formulated and characterised using Transmission Electron Microscopy (TEM) and Fourier-transform infrared (FTIR) spectroscopy. The performance of aluminium oxide (Al2O3) NP on the rheological properties of HPAM in the presence of different electrolyte concentrations representative of field brine and typical reservoir temperatures were investigated. Wettability alteration study of Al2O3 PNF was carried out using DataPhysics optical contact angle (OCA) instrument. Results obtained for Al2O3 PNF were compared to the widely reported SiO2 PNF and base polymer without nanomaterial. Experimental results show that the rheological properties improved while degradation of HPAM macromolecule was inhibited due to the addition of NPs. At 2,000 ppm HPAM solution (25 mol. % degree of hydrolysis), 0.1 wt% NP concentration was found to be the optimal choice for Al2O3 NP which gives rise to the highest viscosity on the rheological characterization. Al2O3 PNF exhibited better steady shear viscosity performance under the different electrolyte concentrations and temperatures studied. Al2O3 PNF altered the wettability of the porous media from oil-wet to water-wetting condition. Finally, oil displacement test in sandstone cores at typical reservoir temperature and salinity showed that Al2O3 PNF had 11.3% incremental oil recovery over conventional HPAM. This study is beneficial for extending the frontier of knowledge in nanotechnology application for EOR

Recent advances and prospects in polymeric nanofluids application for enhanced oil recovery

Enhanced-oil-recovery (EOR) processes are used to recover bypassed and residual oil trapped in the reservoir after primary and secondary recovery methods. Recently, novel materials formed from incorporation of polymer and nanoparticles have gained attention and are proposed for EOR applications due to their fascinating properties. Herein, we review the recent advances and prospects of the application these polymeric nanofluids in crucial aspects of EOR such as stability and adsorption, wettability alteration, interfacial tension reduction and emulsion stability, and rheology. The mechanisms of their improved efficiency were elucidated, gaps in the research were highlighted, and recommendation for future works were outlined