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Around the globe, only 30–50% of the amount of oil estimated to be in reservoirs ("original oil in place") can be obtained using primary and secondary oil recovery methods. Enhanced oil recovery methods are required in the oil processing industry, and the use of microbially produced amphiphilic molecules (biosurfactants) is considered a promising efficient and environmentally friendly method. In the present study, biosurfactants produced by the Pseudomonas putida PP021 isolate were extracted and characterized, and their potential to enhance oil recovery was demonstrated. It was found that the cell-free biosurfactant-containing supernatant decreased the air–water interface tension from 74 to 28 mN m−1. Using TLC and FTIR methods, the biosurfactants produced by the isolate were classified as mono- and di-rhamnolipid mixtures. In the isolates' genome, the genes rhlB and rhlC, encoding enzymes involved in the synthesis of mono- and di-rhamnolipids, respectively, were revealed. Both genes were expressed when the strain was cultivated on glycerol nitrate medium. As follows from the sand-packed column and core flooding simulations, biosurfactants produced by P. putida PP021 significantly enhance the degree of recovery, resulting in additional 27% and 21%, respectively. [ABSTRACT FROM AUTHOR]

To this day, the petroleum industry is still searching for alternative ways to improve the recovery of hydrocarbon from the reservoir. The residual oil blotches may consist of about 30%–40% or more of a volume fraction. Seismic stimulation has great potential for IOR (improved oil recovery), because of its advantages on low cost, high effectivity, and environment-friendly as they introduce no formation damage, etc. The investigation and application of seismic stimulation have been launched for over 70 years. In this study, a literature review on the mechanism for IOR, including laboratory and theoretical modeling work, and oilfield application, is present here. Firstly, four different manners of vibration are introduced, and the seismic vibration with 1 Hz–100 Hz (frequency) and 1 μm–100 μm (amplitude) is the commonly used; Secondly, the mechanisms of IOR by seismic stimulation are summarized as: effect on capillary pressure, pore deformation, relative permeability, thermal and degassing effects, however, further tests and understanding of the mechanisms are necessary. Thirdly, the reviews of experimental research and mathematical modeling based on the published literature are made. Especially, the mathematical modeling of seismic vibration for the real reservoir development (such as non-Darcy flow, low permeability reservoirs, the coupling of non-Newtonian fluid, etc.) is still insufficient. Finally, some successful oilfield applications (in Russia, North America, and China) and prospects are proposed in this work. It will be more efficient to stimulate the reservoirs if the seismic wave is at the formation's resonant frequency. In our work, we don't expect to provide an exhaustive review of the work presented. On the contrary, we hope that our work can provide an introduction for other researchers to get a brief understanding of the seismic stimulation technology and possible results under which conditions the seismic stimulation works well. • Mechanisms of seismic stimulation based on the published literature are introduced. • Reviews of experiments and mathematical modeling on seismic stimulation are made. • Mathematical modeling of seismic vibration for real reservoir is insufficient. • Seismic wave at the formation's resonant frequency can efficient stimulate reservoir. • Seismic stimulation can work together with some chemical-based EOR methods. [ABSTRACT FROM AUTHOR]

Yarega heavy oil field (YHOF) is a naturally fractured heavy oil field where only recently steam‐assisted gravity drainage (SAGD) technology has been introduced. SAGD employed in this field has so far resulted in early steam breakthrough leading to producer well abandonment and recurrent drilling procedures invariably increasing costs. Therefore, as opposed to SAGD, we propose the joint application of cyclic steam injection (CSS) technology with fishtail wells. The advantages of CSS are well documented. The addition of fishtail wells to this strategy assists in reducing the travel time the mobilized oil takes to arrive at a well perforation. Our results demonstrate that the synergy between these two strategies can further improve recoveries in heavy oil reservoirs. A reservoir simulation model of a sector in the YHOF is employed to understand heat/mass transfer mechanisms and for production enhancement recommendations. Different well configuration strategies were tested on this model. Results from the three‐dimensional sector in the YHOF model suggest that in addition to the thermal development technologies employed in this reservoir, CSS coupled with fishtail wells provided favorable steam‐oil ratios, cumulative energy‐oil ratios, and enhanced cumulative oil recovery for a naturally fractured reservoir. Well abandonment issues arising from SAGD approach currently being applied can therefore be eliminated. Based on results from this research, we recommend the testing of a fishtail well development plan with CSS that includes a 10‐day steam injection, 10‐day soaking period, and 10‐day production period. In comparison with continuous steam injection recovery (4.5% over 3 years), our simulation results showed an improved recovery of 7% over the same period with this concept. In addition to the technical advantage of this strategy, favorable steam‐oil and energy‐oil ratios imply that minimal economic costs are achieved and carbon footprints are lessened. [ABSTRACT FROM AUTHOR]

Bazhenov formation is the key kerogen-bearing oil shale reserve in Russia. Therefore, as recovery from conventional reservoirs decreases, the need to find enhanced oil recovery (EOR) techniques in order to develop Bazhenov formation becomes evident. Despite the huge amount of reserves, oil shales in Russia have not been developed extensively due to the absence of suitable recovery technique. High pressure air injection (HPAI) is one of the recovery techniques that has a potential to become the main recovery method. In order to design this method correctly, different aspects must be investigated. To do that, thermal analysis methods should be implemented. In this work, thermomicroscopy, simultaneous thermal analysis and open system pyrolysis were performed to investigate kerogen conversion process. The optical thermomicroscopy showed changes in the macrostructure and the morphology of the Bazhenov shale sample during heating up to 720 °C with the heating rate 10 °C/min. It was demonstrated that the conversion of kerogen into hydrocarbons caused increasing in sample porosity. Geometrical characteristics of pores such as size and shape were determined, dynamic events during the heating were investigated. During the air purge, intensive fracturing occurred along the voids formed due to oxidation of organic matter at 450 °C. The simultaneous thermal analysis (STA) revealed linear relationship between TOC and heat value for single well samples. Interval of oxidation reactions was determined. Bulk-kinetic parameters (activation energy and frequency factor) were calculated by numerical inversion of pyrolysis data using the Kinetics2015 optimization software. Fixing the A factor to a 2×10 14 s −1 and using a spacing of 1 kcal/mole in the discrete activation energy distribution were investigated. In result, solution for different samples along the well was rather stable comparing to traditional approach. [ABSTRACT FROM AUTHOR]

The problem of effective technology for heavy oil recovery nowadays has a great importance, because of worsening geological conditions of the developed deposits, decreasing recovery factor, increasing the part of heavy oil. For the future sustainable development of oil producing industry the involved technologies must require energy effectiveness and ecological safety. The paper proves the enhanced oil recovery methods necessity for heavy oil deposits, highlighted thermal technologies as the most effective. But traditional thermal treatment technologies is a source of air pollutant emission, such as CO, NO etc. The calculation of emissions for traditional steam generator is provided. Besides, the paper shows the effectiveness of electrical enhanced oil recovery methods. The advantages of associated gas as a fuel for cogeneration plants is shown. The main approaches to implementation of carbon dioxide sequestration technologies in the oil and gas industry of Russia are defined. Conceptual view of CO2-EOR technologies potential within the context of sustainable development of oil and gas industry are presented. On the basis of the conducted research a number of scientific research and practical areas of the CCS technology development are revealed. [ABSTRACT FROM AUTHOR]

Development of oil fields by the most common waterflooding method leads to an increase in the water cut of the recoverable oil and a low oil recovery factor (for Russia, about 30–40%). The solution to this actual problem seems to be in the combination of the applied waterflooding method with the elastic wave action. This paper presents the results of the use of acoustic stimulation as an unconventional but promising approach to enhanced oil recovery. This study developed a borehole emitter and acoustic action technology to stimulate oil production. In this borehole hydrodynamic emitter, based on the jet-driven Helmholtz oscillator, the generation of intense acoustic pressure oscillations occurs due to the energy of the fluid flow injected into the formation. Bench tests made it possible to determine the operating parameters and frequency characteristics of the device. Field tests were carried out in Russia at an oil field that is in a late stage of development. An increase in oil production has been achieved; the water cut of the produced oil has been reduced; the injectivity of the injection well has been increased due to the restoration of the filtration properties of the bottom-hole zone. Thus, the developed technical devices, operating at kilohertz frequencies, and the production technology can be used as a promising method for stimulating oil flow and enhancing oil recovery. The advantages of the proposed acoustic treatment are their relatively low cost, simplicity of device design, high efficiency, and environmental friendliness, as well as the possibility of combining this technology with almost all traditional methods of enhanced oil recovery. • Borehole emitter and acoustic technology to stimulate oil production are developed. • Sound oscillations increase the well injectivity with contaminated bottom-hole zone. • Average increase in the oil production rate is 1.68 tons per day (11.8%). • The advantages - small-size equipment, ecologically safe and low operating costs. [ABSTRACT FROM AUTHOR]

Europe is dangerously dependent on Russian natural gas (NG): 13 European nations rely on Russian NG for over 50 % of their requirements. In addition, Europe relies on Russia for about one third of its oil imports. Europe is acutely aware of this high level of energy dependence, which has been, once again, highlighted by the Ukrainian crisis. The European Council March 2014 Brussels Summit Meeting focused on Europe's energy dependence on Russia, especially for NG. The Summit recommended that efforts be intensified to reduce Europe's gas energy dependency and that the EU accelerate diversification of its energy supply. However, via a carefully thought out strategy, Europe can significantly reduce its dependence on Russian energy supplies through greater utilization of clean coal. [ABSTRACT FROM AUTHOR]

Because of the geological characteristics and low permeability of Western Siberia hydrocarbon reservoirs, hydraulic fracturing is the most effective method for improving hydrocarbon production. During recent years, the massive fracturing treatments in this area have led to a reduction of well candidates for this type of production- enhancement technique. Currently, the majority of selected wells for fracture stimulation are considered risky because of significant water cut increase after stimulation. The question arises: How to reduce water production while enhancing oil production? This paper reviews 26 case histories exemplifying the use of relatively permeability modifiers (RPMs) in hydraulic fracturing to enhance oil recovery and control water production. Also, results of laboratory studies are included to support the RPM-fracturing concept and -placement techniques. [ABSTRACT FROM AUTHOR]

In this study, we obtained the first data on the compositional kinetics of the Bazhenov kerogen decomposition, which are essential for estimation of the amount and composition of hydrocarbon products in petroleum system modeling and for simulation of organic matter transformation in the processes of thermal enhanced oil recovery. The Bazhenov Formation is one of the priority oil shale formations in the world and is the principal source rock in the West Siberian Petroleum Basin, Russia. The kinetic study was performed on source rock samples with organic matter spanning the range of thermal maturity from immature to early and middle mature. The experiments included (1) the determination of bulk kinetic spectrum from pyrograms obtained using linear heating of rock samples, (2) a series of isothermal pyro-GС-TOFMS/FID experiments carried out at several levels of organic matter conversion, and (3) the calculation of the compositional kinetic spectrum from the experimental data. The kinetic characteristics of the samples were correlated with organic matter maturity. We have demonstrated that with an increase of organic matter maturity, the maximum of activation energy distribution shifts from 51 to 53 kcal/mol (for a fixed frequency factor A = 1⋅1014 s-1). The kerogen destruction products analyses reveal that for the immature sample the total gas yield is 39%, the percentage of heavy hydrocarbons С 16+ is 16%, and the percentage of С 7 -C 10 is two times higher than that of С 11 -C 15 : 30 and 15%, respectively. With the increase of organic matter maturity, the proportion of gas and heavy products decreases. Regardless of organic matter maturity nor conversion degree, the main products of the Bazhenov kerogen transformation are liquid hydrocarbons C 7 –C 10 , the percentage reaches 54% in the maximum of oil generation. • Compositional kinetic spectra for the Bazhenov kerogen decomposition in open system. • Oil content in kerogen transformation products reaches 62% in oil window zone. • Gas and heavy hydrocarbons yield decreases with maturation of the Bazhenov kerogen. • Kinetic data are applicable in petroleum system modeling and EOR optimization. [ABSTRACT FROM AUTHOR]