Hasnah Mohd Zaid

The Effect of Nanoparticles Crystallite Size on the Recovery Efficiency in Dielectric Nanofluid Flooding

Application of nanotechnology in enhanced oil recovery (EOR) has been increasing in recent years. After secondary flooding, more than 60% of the original oil in place (OOIP) remains in the reservoir due to trapping of oil in the reservoir rock pores. One of the promising EOR methods is surfactant flooding, where substantial reduction in interfacial tension between oil and water could sufficiently displace oil from the reservoir. In this research, instability at the interfaces is created by dispersing 0.05 wt% ZnO nanoparticles in aqueous sodium dodecyl sulfate (SDS) solution during the core flooding experiment. The difference in the amount of particles adsorbed at the interface creates variation in the localized interfacial tension, thus induces fluid motion to reduce the stress. Four samples of different average crystallite size were used to study the effect of particle size on the spontaneous emulsification process which would in turn determine the recovery efficiency. From the study, ZnO nanofluid which consists of larger particles size gives 145% increase in the oil recovery as compared with the smaller ZnO nanoparticles. In contrast, 63% more oil was recovered by injecting Al2O3 nanofluid of smaller particles size as compared to the larger one. Formation of a cloudy solution was observed during the test which indicates the occurrence of an emulsification process. It can be concluded that ultralow Interfacial tension (IFT) value is not necessary to create spontaneous emulsification in dielectric nanofluid flooding.

Microscopic evolution of dielectric nanoparticles at different calcination temperatures synthesized via sol-gel auto-combustion

Dielectric nano powder synthesis is carried by a simple and fast sol-gel auto-combustion method. The transformation of crystalline phases of as-synthesized nano powders is investigated through the detailed transmission electron microscopy (TEM), revealed the crystallographic alterations and morphological information even at lattice scale. From specific area electron diffraction (SAED) pattern, has specified the d-spacing and corresponding planes supported by the observed lattice fringes. The morphological characterization of nanoparticles is performed through field-emission scanning electron microscopy (FESEM), exhibiting the increment in particle size due to agglomeration with the increase in annealing temperature. Furthermore, EDX pattern has been used to verify the formation of nanoparticles by revealing the presence of required elements.

Application of Electromagnetic Waves and Dielectric Nanoparticles in Enhanced Oil Recovery

Enhanced oil recovery (EOR) refers to the recovery of oil that is left behind in a reservoir after primary and secondary recovery methods, either due to exhaustion or no longer economical, through application of thermal, chemical or miscible gas processes. Most conventional methods are not applicable in recovering oil from reservoirs with high temperature and high pressure (HTHP) due to the degradation of the chemicals in the environment. As an alternative, electromagnetic (EM) energy has been used as a thermal method to reduce the viscosity of the oil in a reservoir which increased the production of the oil. Application of nanotechnology in EOR has also been investigated. In this study, a non-invasive method of injecting dielectric nanofluids into the oil reservoir simultaneously with electromagnetic irradiation, with the intention to create disturbance at oil-water interfaces and increase oil production was investigated. During the core displacement tests, it has been demonstrated that in the absence of EM irradiation, both ZnO and Al2O3 nanofluids recovered higher residual oil volumes in comparison with commercial surfactant sodium dodecyl sulfate (SDS). When subjected to EM irradiation, an even higher residual oil was recovered in comparison to the case when no irradiation is present. It was also demonstrated that a change in the viscosity of dielectric nanofluids when irradiated with EM wave will improve sweep efficiency and hence, gives a higher oil recovery.

Effect of EM propagation medium on electrorheological characteristics of dielectric nanofluids

ABSTRACT The effect of dielectric loss on the electrorheological (ER) characteristic of dielectric nanofluids under shear was studied. When nanofluids are activated by an applied electric field, it behaves like a non-Newtonian fluid under ER effect by creating the chains of nanoparticles. ER characteristics of ZnO and Al2O3 nanofluids with various nanoparticles concentration (0.1, 0.05, 0.01 wt%) were measured. For this purpose, a solenoid-based electromagnetic (EM) transmitter was used under different propagation media including air, tap water, and salt water. The result shows that all the nanofluids exhibit pseudo-plastic behavior, while the electric field causes a significant increase in viscosity in the presence of tap water, followed by salt water. Additionally, the viscosity of nanofluid shows a high dependence on particle loading. A possible mechanism was also proposed to describe the effect of dielectric properties on the ER behavior of dielectric nanofluids. GRAPHICAL ABSTRACT

Novel Enhanced Oil Recovery Method Using Co2+xFe2+1-xFe3+2O4 as Magnetic Nanoparticles Activated by Electromagnetic Waves

Research on the application of nanoparticles, specifically magnetic nanoparticles in enhanced oil recovery has been increasing in recent years due to their potential to increase the oil production despite having to interact with reservoirs of high salinity, high pressure and temperature and un-natural pH. Unlike other conventional EOR agents e.g. surfactants and polymers, a harsh environment will cause degradation and failure to operate. Magnetic nanoparticles which are activated by a magnetic field are anticipated to have the ability to travel far into the oil reservoir and assist in the displacement of the trapped oil. In this work, ferromagnetic Co2+xFe2+1-xFe3+2O4 nanoparticles were synthesized and characterized for their morphological, structural and magnetic properties. At a composition x = 0.75, this nanomaterial shows its best magnetisation parameters i.e. highest value of saturation magnetization, remanence and coercivity of 65.23 emu/g, 12.18 emu/g and 239.10 Oe, respectively. Subsequently, a dispersion of 0.01 wt% Co2+0.75Fe2+0.25Fe3+2O4 nanoparticles in distilled water was used for core flooding test to validate its feasibility in enhanced oil recovery. In a core flooding test, the effect of electromagnetic waves irradiation to activate the magnetization of Co2+0.75Fe2+0.25Fe3+2O4 nanofluid was also investigated by irradiating a 78 MHz square wave to the porous medium while nanofluid injection was taking place. In conclusion, an almost 20% increment in the recovery of oil was obtained with the application of electromagnetic waves in 2 pore volumes injection of a Co2+0.75Fe2+0.25Fe3+2O4 nanofluid.

Improved Oil Recovery by High Magnetic Flux Density Subjected to Iron Oxide Nanofluids

Oil recovery in offshore environments can be increased by using nanofluids with electromagnetic waves generated from an antenna in the oil reservoir. In the case of offshore environments, these constraints can be avoided if a horizontal antenna is towed close to the seabed, which maximises the electromagnetic energy transferred from the overburden to the reservoir and nanofluids in the reservoir. In this research, a new enhanced antenna is used with iron oxide (Fe2O3) and zinc oxide (ZnO) nanofluids for oil recovery applications at the laboratory scale. In the antenna study, it was observed that the curve antenna with magnetic feeders gave a 1978% increase in the magnetic field signal strength compared to the case without magnetic feeders. The curve antenna with magnetic feeders produced a 473% increase in the electric field signal strength compared to the case without magnetic feeders. Iron oxide (Fe2O3) nanoparticles were prepared by the sol-gel method. The iron oxide (Fe2O3) nanoparticle sizes were in the range of 30.27-37.60 nm. FESEM and HRTEM images show that the samples have good crystallinity and that the grain size increased as temperature increased. Iron oxide (Fe2O3) samples sintered at 500°C showed a high initial permeability and Q-factor and a low loss factor compared to samples sintered at 500°C. The sample had a very high initial permeability and a low loss at low frequencies; therefore, it was suitable for the preparation of the nanofluid and oil recovery applications. Oil recovery through the usage of 0.1 % (w/w) iron oxide (Fe2O3) nanofluid with an EM field generated from the curve antenna with magnetic feeders was 33.45% of OOIP (original oil in place). In a similar case where 0.1 % (w/w) zinc oxide (ZnO) nanofluid with an EM field was used, 22.46 % of OOIP was recovered. These results imply that injecting 0.1% w/w iron oxide nanofluid coupled to the curve antenna with magnetic feeders has potential for oil recovery for improved water flooding systems because the high magnetic flux density that acts on the nanoparticles is proportional to the magnetic field strength.

The Band Structures of Single-Walled Carbon Nanotubes and ZnO Nanoparticles Used for Oil Recovery in Water Flooding System

A major challenge for the oil industry is increasing the oil recovery from reservoirs. Nanofluid injection with the aid of electromagnetic (EM) waves can improve oil recovery. Nanoparticles of zinc oxide (ZnO) were synthesised using a sol-gel method and characterised using X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). Nanofluids of SWCNT and zinc oxide (ZnO) were used in this oil recovery study. It was observed that curved antennae with magnetic feeders gave a 472% larger D-field signal than those without magnetic feeders. The Dmol3 simulations showed that the band gap of ZnO is 1.088 eV, and the band gap of the SWCNT was 0.326 eV. The particle sizes of the ZnO nanoparticles were in the range of 30-39 nm. FESEM and HRTEM images showed that the samples were highly crystalline, and the grain size increased as the temperature increased. As a result, these nanoparticles were suitable for the preparation of the nanofluid and oil recovery applications. Oil recovery using 0.001% (w/w) ZnO nanofluid and EM was 16.10 % of OOIP, and using 0.01% SWNT nanofluid yielded an oil recovery of 23 ROIP %. These results imply that injecting a ZnO oxide nanofluid of 0.001% w/w coupled with a curved antenna and magnetic feeders has the potential to improve oil recovery in waterflooding systems.

Effect of Zinc Oxide Nanoparticle Sizes on Viscosity of Nanofluid for Application in Enhanced Oil Recovery

Zinc oxide (ZnO) with different nanoparticle (NP) sizes was prepared and synthesized by using the sol-gel method with organic precursor, followed by the characterization of the ZnO nanoparticle by using X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) to identify the effect of nanoparticle sizes of ZnO on the viscosity of the nanofluid. The impact of nanoparticle sizes on EOR was investigated. Results showed both viscosity and interfacial tension (IFT) increased with the nanoparticle size.

Effect of Annealing Temperature on the Crystallization of Hematite-Alumina (Fe2O3-Al2O3) Nanocomposite and its Influence in EOR Application

Usage of magnetic materials is not unusual in oil and gas research, specifically in enhanced oil recovery (EOR) where various magnetic micro-and nanoparticles were used to enhance sweep efficiency, reducing interfacial tension and heat generation. Magnetic nanoparticles which are activated by a magnetic field are anticipated to have the ability to travel far into the oil reservoir and assist in the displacement of the trapped oil. In this work, magnetic Fe2O3-Al2O3 nanocomposite was synthesized and characterized for its morphological, structural and magnetic properties. At an annealing temperature of 900°C, this nanomaterial starts to exhibit magnetization as the composite structure crystallizes to the stable Fe2O3 and Al2O3. Subsequently, dispersion of the 0.01 wt% Fe2O3-Al2O3 nanocomposite in distilled water was used for displacement tests to validate its feasibility to be applied in EOR. In the displacement test, the effect of electromagnetic waves on the magnetization of Fe2O3-Al2O3 nanofluid was also investigated by irradiating a 13.6 MHz square wave to the porous medium while nanofluid injection is taking place. In conclusion, an almost 20% increment in the recovery of oil was obtained with the application of electromagnetic waves in 2.4 pore volumes (PV) injection of Fe2O3-Al2O3 nanofluid.

Development of novel electromagnetic antenna for deep target marine CSEM survey

Marine controlled source electromagnetic method (MCSEM) is a new and versatile method for hydrocarbon detection. Deep sea hydrocarbon reservoir exploration is still challenging and expensive. Due to unreliability for the detection of DHIs using seismic data, new methods have been investigated. Sea bed logging (SBL) is a new technique for the detection of deep target hydrocarbon and has potential to reduce the risks of DHIs (direct hydrocarbon indicators) in deep sea environment. The magnitude of EM waves is very important for the detection of deep target hydrocarbon reservoir below 4000m from the sea floor. Nanotechnology has been introduced very effective and shows promising results in many research fields. Ferrite magnetic materials play an important role in many applications due to its versatile magnetic properties. The aluminum based EM antenna is developed and NiZn, YIG ferrite as magnetic feeders are used to increase the field strength from EM antenna. FESEM images show that grain size increases wit...