Enhanced oil recovery for emergent energy demand: challenges and prospects for a nanotechnology paradigm shift.

Renewable and non-renewable energy sources remain the two fronts for meeting global emergent energy demand. Renewable energy sources such as crude oil, in meeting energy needs, is a function of new hydrocarbon discoveries and improving the recovery of existing oil fields. However, new crude oil discoveries are made at a decreasing rate; likewise, existing fields are at a declining phase with conventional recovery techniques not being able to produce as much as two-thirds of the oil in place. In complementing existing oil recovery techniques, research into the use of nanotechnology has emerged as a potential alternative for tertiary oil recovery scheme. Despite the promising results, there has not been any reported large-scale field application of nanotechnology in the oil and gas industry except for some small-scale field trials. In this paper, a detailed review of developments on nano-enhanced oil recovery (Nano-EOR) and its attendant challenges are presented. Furthermore, key recommendations were given for future research on Nano-EOR. While the adoption of new technologies has its associated risks, the future prospects of Nano-EOR remains very high

Predictive modelling of the impact of silica nanoparticles on fluid loss of water based drilling mud

Research into the use of nanoparticles for drilling mud formulation is gaining momentum but a key challenge involves predicting the effect of nanoparticles on the properties of the modified mud. Mathematical models used in the description of drilling muds allow for a generalised computation of drilling performance. In other words, such models cannot quantitatively capture the contributions of nanoparticles to the overall performance of the nano-modified drilling mud. In this work, a new model was derived which describes the fluid loss of nanoparticle enhanced water based drilling mud under static filtration. This was done taking into account the structural kinetics of the bentonite suspension and colloidal behaviour of the nanoparticles.The new fluid loss model was compared with the known API static fluid loss model using statistical measures,Root Mean Square Error (RMSE) and Coefficient of Determination (R2). The new model compares favourably with the API static model with RMSE and R2 values of 0.41–0.81 cm3 and 99.3–99.89% respectively.The new fluid loss model was able to predict a value for the maximum fluid loss. It also accounted for variation in mud cake permeability and solid fraction, which could not be explained by the API fluid loss model

Evaluating the Oil Mobilization Properties of Nanoparticles Treated with Arabic Gum and Xanthan Gum for Trapped Oil in Porous Media

The flow of multiple fluid phases in porous media often results in trapped droplets of the non-wetting phase. Recent experimental and theoretical studies have suggested that nanoparticle aqueous dispersions may be effective at mobilizing trapped droplets of oil in porous media. Hypotheses to explain the observation include the nanoparticles' modification of solid wettability, changes in interfacial tension and interface rheology. The difficulty in observing droplet behavior on the pore scale has made the understanding of such mechanism still unclear. In this work, the relationship between nanoparticle concentration and microscopic diversion of flow was investigated and how this impacts on the oil mobilization efficiency. Also investigated in this work was how the rheology of the dispersion medium for nanoparticles impacts on the overall recovery of trapped oil in porous media. A core flooding experiment was carried out on which aqueous solutions of different concentrations of the nanoparticle dispersion was used as the displacing fluid likewise rheological modified solutions of the nanofluids. The output of this work showed that the nanoparticle concentration impacts on the recovery of trapped oil through the microscopic diversion of fluid flow in porous media and this phenomenon in conjunction with earlier mention hypothesis effectively showed how nanoparticles enhances the recovery of trapped oil in porous media

Oil Price Slump: Investigating the Market Dynamics of the Role of the Oil Titans and its Global Impact

The oil price decline has been the subject of major captions in the last months and has been outlined virtually in terms of the economics of oil market with a number of media outlets accusing Saudi Arabia and its OPEC Trojan horse of deliberately bringing low the price of crude oil. The widely reported aim of this oil price slump brought about by Saudi Arabia and OPEC is to initiate severe harm to the world's major oil exporters – particularly Russia. Also, Saudi Arabia and its OPEC cartel have a vested desire in getting rid of higher-cost competitors, such as US shale oil producers, who will definitely be hurt by the slump in oil price. High prices spurred companies in North America to begin production of “difficult to produce crude” in the shale formation of North Dakota and oil sand of Alberta. Before the price slump, Saudi Arabia was selling its oil to China at a rebate. OPEC's rejection to reduce production looked like the plainest evidence yet that the oil price decline was indeed an oil price battle between Saudi Arabia and the US. This paper looked at the role of the various oil titans in the current oil price decline and investigates if the reasoning behind it goes beyond OPEC simply driving down the price of crude oil to gain back lost market share and get rid of US shale oil competition. Keywords: Crude Oil Price, OPEC, Shale Oi

Effect of aluminum oxide nanoparticles on the rheology and stability of a biopolymer for enhanced oil recovery.

Uncommon and untested biopolymers in field pilot studies, but applied in laboratory studies are combined with Al2O3 nanoparticles to form nanocomposites for enhanced oil recovery (EOR) performance evaluation. Core plug samples of the Niger Delta region and Berea sandstone were used as the porous media for EOR experiments. Incremental oil recovery sequel to waterflooding (secondary recovery) was 5–12% and 5–7% for potato starch nanocomposite (PSPNP) and gum Arabic nanocomposite (GCNP) respectively. The biopolymer nanocomposites showed improved viscosity over the biopolymers. Thus, the nanoparticle served as a viscosity modifier on one-hand and stability enhancer on the other. EOR was affected by biopolymer and nanoparticle concentration with the attendant catch-22 situation of permeability impairment. The overall higher incremental recovery of applying PSPNP came by an intermediate potato starch (PSP) flooding between waterflooding and PSNP flooding. Consequently, slugs of biopolymer and biopolymer nanocomposite may be the way forward knowing that the biopolymers studied have surface-active constituents

Properties and application of Nigerian bentonite clay deposits for drilling mud formulation: Recent advances and future prospects

The vast deposits of Nigerian bentonite clay have many significant uses in different aspects of industrial fields of which the oil and gas industry is a potential consumer of this clay mineral. In this review article, the key mineralogical characteristics and rheological properties of these clay deposits in various locations and their related application for drilling mud formulation were comprehensively reviewed. Various research efforts on these bentonite clay deposits over the past couple of years were summarized with some critical comments and analysis. Attention was given to the clay reserve estimates, mineralogy of the clay deposits, chemical modification of the clays, rheological properties of drilling mud formulated from these clays and its suitability for drilling operations. Moreover, future prospects and key problems to be solved regarding the use of Nigerian bentonite deposits for drilling mud formulation were discussed. This review shed new light on both fundamental and practical studies that are concentrated on the use of Nigerian bentonite for drilling mud formulation

Time since faecal deposition influences mobilisation of culturable E. coli and intestinal enterococci from deer, goose and dairy cow faeces

Mobilisation is a term used to describe the supply of a pollutant from its environmental source, e.g., soil or faeces, into a hydrological transfer pathway. The overarching aim of this study was to determine, using a laboratory-based approach, whether faecal indicator bacteria (FIB) are hydrologically mobilised in different quantities from a typical agricultural, wildlife and wildfowl source, namely dairy cattle, red deer and greylag goose faeces. The mobilisation of FIB from fresh and ageing faeces under two contrasting temperatures was determined, with significant differences in the concentrations of both E. coli and intestinal enterococci lost from all faecal sources. FIB mobilisation from these faecal matrices followed the order of dairy cow > goose > deer (greatest to least, expressed as a proportion of the total FIB present). Significant changes in mobilisation rates from faecal sources over time were also recorded and this was influenced by the temperature at which the faecal material had aged over the course of the 12-day study. Characterising how indicators of waterborne pathogens are mobilised in the environment is of fundamental importance to inform models and risk assessments and develop effective strategies for reducing microbial pollution in catchment drainage waters and associated downstream impacts. Our findings add quantitative evidence to support the understanding of FIB mobilisation potential from three important faecal sources in the environment

Impact of Freeze-Thaw Cycles on Die-Off of E. coli and Intestinal Enterococci in Deer and Dairy Faeces: Implications for Landscape Contamination of Watercourses

Characterising faecal indicator organism (FIO) survival in the environment is important for informing land management and minimising public health risk to downstream water users. However, key gaps in knowledge include understanding how wildlife contribute to catchment-wide FIO sources and how FIO survival is affected by low environmental temperatures. The aim of this study was to quantify E. coli and intestinal enterococci die-off in dairy cow versus red deer faecal sources exposed to repeated freeze–thaw cycles under controlled laboratory conditions. Survival of FIOs in water exposed to freeze–thaw was also investigated to help interpret survival responses. Both E. coli and intestinal enterococci were capable of surviving sub-freezing conditions with the faeces from both animals able to sustain relatively high FIO concentrations, as indicated by modelling, and observations revealing persistence in excess of 11 days and in some cases confirmed beyond 22 days. Die-off responses of deer-derived FIOs in both faeces and water exposed to low temperatures provide much needed information to enable better accounting of the varied catchment sources of faecal pollution and results from this study help constrain the parameterisation of die-off coefficients to better inform more integrated modelling and decision-making for microbial water quality management

Persistence of E. coli in Streambed Sediment Contaminated with Faeces from Dairy Cows, Geese, and Deer: Legacy Risks to Environment and Health

Legacy stores of faecal pollution in streambed sediments can result in delayed impacts on environmental quality and human health if resuspended into the overlying water column. Different catchment sources of faecal pollution can contribute to a legacy store of microbial pollutants, with size of stores influenced by microbial die-off and faecal accrual rates in the streambed. The aim of this study was to use a mesocosm experiment to characterise the persistence of E. coli derived from faeces of dairy cows, deer, and geese once introduced to streambed sediment under different temperature regimes. The settling rate of solid constituents of faecal material into streambed sediment once delivered into an aquatic environment was also quantified. The persistence patterns of E. coli in streambed sediment were found to vary as a function of faecal source and temperature; die-off of E. coli in sediment contaminated with goose faeces was more rapid than in sediments contaminated with dairy cow or deer faeces. Goose faeces also recorded a more rapid settling rate of faecal particles through the water column relative to dairy cow and deer faeces, suggesting a more efficient delivery of E. coli to streambed sediments associated with this faecal source. Our findings provide new evidence to improve understanding of the potential longer-term risks to both the environment and public health posed by sediments when contaminated with livestock, wildlife, and wildfowl faeces