Enhance Oil Production Research Articles

Evaluation and improvement of CO2 assisted gravity drainage for enhanced oil production in China

In view of the diversity of petroleum reservoir types, most petroleum reservoirs have very strong heterogeneity in properties. For many water flooding reservoirs, with the continuous water injection process, the effect of enhancing oil recovery begins to deteriorate gradually, and a large amount of remaining oil mainly remains at the top of the reservoir formation, becoming as "attic oil". Under the "double carbon" target, in order to cope with the high demand for oil consumption in China, a new oil exploitation technology, CO2 assisted gravity drainage is explored in this study. Taking four cores with similar porosity and permeability as research objects, laboratory displacement experiments were carried out to verify the effectiveness of CO2 assisted gravity drainage in enhancing oil recovery through different CO2 injection methods and injection rates. Moreover, through the comparison of gas flooding recovery factors under different gas injection rates, it is found that the stable control of gas-oil interface is the key to the successful implementation of CO2 assisted gravity drainage. After that, based on references and numerical simulation, this paper analyzes the technical key points of the successful implementation of this technology, proposes the method of introducing "surfactant + CO2" composite system to regulate the stability of gas-oil interface, and clearly points out the issues to be focused in future researches. The study can provide a useful reference for the field implementation of CO2 assisted gravity drainage, and then promote effective carbon utilization and oil production.

Artificial neural networks in predicting of the gas molecular diffusion coefficient

The diffusion coefficient is one of the most important parameters for designing two-phase operations between liquid and gas phases in refineries and petrochemical industries, as well as for the gas injection process in oil fields to enhance oil production. Accurate knowledge of this parameter is essential for the prediction of the dissolution rate of the gas phase into the liquid phase. Ideally, this parameter should be obtained experimentally. Given that setting up laboratory equipment and conducting experiments can be costly and time-consuming, mathematical modeling is used as an alternative. In some cases, this data is not either available or reliable, which poses a challenge for designs. Hence, empirically derived correlations are used to predict molecular diffusion coefficients. However, the success of empirical models depends mainly on the range of data at which they were originally developed. Empirical models are not comprehensive for applying to the other data. Recent studies demonstrated that the alternative approach to modeling complex processes and identifying the effective parameters is the artificial neural network (ANN), a suitable prediction method. This study presents a new model developed to predict the molecular diffusion coefficient of methane in crude oil. The model is developed using 172 data points collected from recent literature. Out of the total laboratory data, 90% (155 data points) were used for training the desired neural network, while 10% (17 data points) were reserved for testing and evaluating the performance of the network. The multi-layer perceptron (MLP) neural network architecture with back-propagation (BP) training algorithm was used successfully for the prediction of diffusion coefficients of methane in crude oil. The developed model is compared with the empirical data, which shows the developed model predicts the methane molecular diffusion coefficient in crude oil with an average absolute error of 4.18%.

Experimental study on countercurrent imbibition in tight oil reservoirs using nuclear magnetic resonance and AFM: Influence of liquid–liquid/solid interface characteristics

Countercurrent imbibition of the fracturing fluid is of much significance for enhancing oil production in tight oil reservoirs during the shut-in period after hydraulic fracturing. The addition of enhanced imbibition agents such as surfactants and nanoparticles into the polymer-based fracturing fluid is conducive to oil production. How different types of imbibition agents affect oil recovery and the applicable conditions for different imbibition agents, however, still need to be clarified. In this article, we used low-field nuclear magnetic resonance (NMR) to measure the one-dimensional (1D) oil signal profiles along the imbibition direction during the countercurrent imbibition process and determine the imbibition distance and water saturation of different imbibition agents including polymer, surfactant, nano-silica (NS) and NS-surfactant complexes. Moreover, by measuring oil–water interfacial tension (IFT), and the adhesion forces between alkanes and the hydrophobic surfaces before/after the imbibition agent treatments by atomic force microscope (AFM), the IFT reduction and wettability alteration abilities of these agents were evaluated. After the NS-surfactant complexes treatment, the adhesion force which represents the force required to pull off oil from the rock surface became the lowest (15.81 pN), merely a quarter of that of NS (73.48 pN) and surfactant (70.01 pN), indicating a superior capability of NS-surfactant to improve wettability. The imbibition efficiency of the four systems in terms of imbibition distance and oil recovery was: NS-surfactant complexes: 38.43 mm 13.2 % > nonionic surfactant: 32.15 mm 9.0 % > NS: 25.88 mm 7.6 % > polymer: 17.64 mm 4.9 %. NS-surfactant nanofluid displayed the longest imbibition distance and highest water saturation, thus possessing the highest imbibition oil recovery. Nonionic surfactant with an IFT of 4.19 mN/m could greatly reduce the IFT compared with NS (35.98 mN/m), but the recovery enhancement induced by IFT reduction was not significant. In contrast, the increase in oil recovery by wettability alteration was distinctly higher than that by IFT reduction, as indicated by the recovery difference between NS-surfactant complexes and surfactant. Accordingly, wettability alteration is the primary mechanism to enhance imbibition oil recovery when ultralow IFT cannot be achieved. This research provides guidance on which type of imbibition agent should be selected to improve imbibition efficiency.

THE USE OF CARBON DIOXIDE AS AN OPTION TO INTENSIFY OIL PRODUCTION IN OIL FIELDS OF TATARSTAN

The use of carbon dioxide in the oil and gas industry is an actual topic. The creation of underground gas storage (UGS) is an important issue for the Republic of Tatarstan. This article examines one of the oil fields in the Republic of Tatarstan as a prospective candidate for carbon dioxide utilization. The analysis in the paper focuses on the geological perspective of the field, considering the rocks reservoir properties, both in terms of core samples and well logging data. Criteria and peculiarities from the standpoint of developing an active oil field are also discussed. The article discusses various methods of using carbon dioxide as an alternative for enhancing oil production. The analysis conducted allows for an assessment of the suitability of using carbon dioxide in the development of the field for both oil production and carbon dioxide sequestration in the reservoir. Consequently, the potential of the field for use as a UGS in the Republic of Tatarstan is examined. The creation of UGS facilities is of great importance today, providing the opportunity to store carbon dioxide underground and serving as an alternative method for intensifying oil production.

Water security threats and solutions in the Grande River basin – One of the Brazilian agricultural frontiers

This paper evaluates the effectiveness of sustainable agricultural management solutions at a farm level to mitigate water security threats in one of Brazil's agricultural frontiers – the Grande River basin. The paper addresses future challenges to water security in the river basin and explores how effective solutions are at a farm level to mitigate current and future water security threats at a basin scale. Based on the assessment of multiple drivers, higher future water security threats in the region are predicted in 2040 due to climate change, land use modification and corresponding changes in water use. The paper finds that the Formosa do Rio Preto region, which is not currently water-insecure, may turn into a water security hotspot area by 2040. The effective response index for water security (ERI-WS), based on the qualitative assessment of the impact at the farm scale, is used to evaluate the effectiveness of current sustainable management practices in addressing water security challenges. The water security dimensions approach of the ERI-WS shows that >50 % of the sites have technologies that can have positive impacts on the “Drinking water and human well-being”, “Economic activities and development”, “Ecosystem” and the “Resilience” dimensions. The paper finds that 66 % of the farms have efficient soil, land, and water management solutions (ERI-WS > 0.5) to address current and future water security issues. These solutions range from sustainable grazing land management to integrated plant nutrition management to enhanced soil productivity. However, 15 % of the farms located in vulnerable areas of the municipalities of São Desidério, Barreiras and Catolândia have lower effectiveness. Results also indicate that 36 % of the sites, distributed in 8 municipalities, employ nature-based solutions to mitigate water security threats, mainly those related to water quality conditions in downstream areas, indicating the relevance of these practices in the region.

Alternative stable microbiome state triggered by the introduction of functional microbes in oil reservoirs drives sustainable microbial enhanced oil recovery

Microbial enhanced oil recovery (MEOR) is a promising substitute for other enhanced oil recovery methods in terms of sustainable development. However, the response mechanism of the microbial community to the introduction of functional microbes remains unclear, which limits MEOR strategic planning to achieve a long-term effect. In this study, we reveal the existence of alternative stable states in an oil reservoir for the first time and examine the correlation between the microbiota status and the oil production increment. There existed a basal state A and alternative state B in the reservoir microbial community, and this resulted in a differential microbial oil displacement effect. The oil production increased by up to 50% in basal state A, because Halomonas dominated most niches and restrained other functional microbes. The introduction of biosurfactant-producing bacteria triggered the microbiota status to shift to the alternative state B associated with higher oil recovery. In state B, the high microbial diversity and positive interaction among Dietzia, Bacillus and other species significantly activated the effectiveness of the microbial oil displacing function. Due to the hysteresis of the microbial community, it required frequent and intensive introduction of functional microbes to improve the microbiota in the reservoir and sustainably promote oil recovery. Overall, this study provides new insights into the response mechanism of the microbial community to the introduction of functional microbes in an oil reservoir. This study also provides guidance for effective management of a MEOR strategy to achieve sustainably enhanced oil production.

Soil Science and Sustainable Farming: Paving the Way for Food Security

The review titled "Soil Science and Sustainable Farming: Paving the Way for Food Security" explores the critical role of soil science in achieving sustainable agriculture and ensuring global food security. The review focuses on key aspects of soil science that contribute to sustainable farming practices, including soil health assessment, soil management practices, soil conservation strategies, soil amendments and nutrient management, and soil-water interactions. Each subheading delves into specific topics within soil science, highlighting their importance in promoting soil fertility, preventing erosion and land degradation, balancing crop nutrition, and optimizing irrigation and water use efficiency. By understanding and implementing these soil science principles, farmers can adopt sustainable practices that enhance soil productivity, preserve natural resources, and support long-term food security.

Impact of extended dryland crop rotation on sustained potato cultivation in Northwestern China

Sustainable agricultural development is challenged by the growing population and increasing instances of drought. Over multiple years, the continuous planting of potatoes can lead to a decrease in both potato yield and soil quality. Crop rotation proves to be a viable solution for enhancing soil productivity, especially in arid and semi-arid areas. A 5-year field experiment was conducted in northwestern China's semi-arid region to evaluate the impact of different potato rotation treatments (1-year rotation with maize, 3-year rotation with maize, oil flax and broad bean; 2-year continuous potato planting rotated with maize and 5-year continuous potato planting) and mulching techniques (unmulched and plastic film) on potato yield and soil fertility. The results showed that crop rotation (1-year and 3-year) improved plant height, dry matter accumulation, soil quality, and reduced water footprint. Under plastic film mulching mode, 1-year rotation resulted in an increase in number of potatoes per plant by 38.24%, economic benefits by 9.70%, water use efficiency by 41.86 and soil fertility in comparison to the 5-year continuous planting, the tuber yield significantly increased by 78.86%, and the green/grey/total water footprint reduced by 28.8%–46.4%. We recommend the 1-year rotational cropping system using plastic film mulch as an effective technique for addressing the challenges of continuous potato cultivation in arid and semi-arid regions.

Fast co-pyrolysis behaviors and synergistic effects of corn stover and polyethylene via rapid infrared heating

Rapid infrared heating with fast heating rates and the capacity to load materials on the gram scale help investigate the co-pyrolysis behaviors, minimizing the gap of materials’ pyrolysis temperature and volatile release during the co-pyrolysis. This work explored the effects of temperature and heating rate on the co-pyrolysis product s behaviors and synergistic interactions of corn stove and polyethylene. Initial increases in oil yield were followed by decreases when the heating rate rose, and when the temperature increased from 500 °C to 600 °C, the oil yield rose from 17.91 wt% to 20.58 wt% before falling to 14.75 wt% at 800 °C. High heating rate promoted the oil generation, and the maximum oil yield was at 25 °C/s with varying heating rates from 15 °C/s to 35 °C/s. The pyrolysis gas produced at 25 °C/s exhibited the highest LHV (Low heating value) and lowest CO2 yield, which were 17.23 MJ/nm3 and 39.29 vol%, respectively. The suitability of heating rate and temperature may improve the interaction between H-radicals of PE and oxygenated groups of CS to generate stable macromolecular compound and enhance oil production. GC–MS studies of the oil products demonstrated that oxygenated compounds such as furans, phenols and acids from lignocellulosic depolymerization had been converted to high molecular weight long chain alcohols (mostly C26, C20 and C14 alcohols) via stronger interactions during fast infrared-heated co-pyrolysis. The alcohols increased from 32.29 % to 65.06 % as temperatures rose from 500 °C to 800 °C. Few furan heterocycles, acids and phenols were detected, suggesting that the oil presented higher quality and stronger synergistic effects. Rapid infrared heating accelerated the synergistic effects between volatile-volatile interactions during co-pyrolysis of corn stover and polyethylene, and the increases in temperature and heating rates further enhanced the release of many volatile substances and the formation of fine pores. Raman results showed char of 600 °C deposited more pure aromatic structures, the influence of temperature on aromatization was stronger than that of heating rate.

Comparative studies on numerical sensitivity of different scenarios of enhanced oil recovery by water-alternating-gas (CO2) injection

Enhanced oil recovery by CO2 injection technology (CO2-EOR) plays a crucial role in enhancing oil production and the permanent sequestration of anthropogenic CO2 in depleted oil reservoirs. However, the availability of CO2 in oil field locations and its mobility in contrast with reservoir fluids are prime challenges in CO2-EOR. The cost of CO2 and its availability at the oil fields has prompted investigations on efficient injection of CO2 at the fields to achieve the best sweep efficiency possible. Injection strategies such as water-alternating-gas (WAG), simultaneous vertical and horizontal WAG, simultaneous water injection into the aquifer and vertical WAG, water and gas injection simultaneously but separately (SS-WAG), and water and gas injection simultaneously but not separately (SNS-WAG) play a significant role, as well as the purity of CO2. In this work, the significance of the above criteria was investigated individually and in combination. The coupled sequence of injection rate, soaking time, WAG ratio, and purity of injected CO2 for enhancement of oil production were delineated. A realistic reservoir simulation model conceptualizing the CO2-EOR system with five spot injection patterns was developed by the company CMG. The history-matched model that was developed was used to investigate the sensitivity of the coupled effects to the criteria listed above on oil recovery. Numerical investigations quantitatively emphasized that purity and soaking time of CO2 have an inverse effect in the oil production rate and that SNS-WAG resulted in a better oil production rate than SS-WAG.

Laboratory tests and field pilot of foam-assisted deoxidized-air flooding in a low-permeability sandstone reservoir

Foam-assisted deoxidized-air flooding is a promising technique for improving oil recovery, particularly in low-permeability oil reservoirs. However, significant differences in displacement efficiency have been observed. A comprehensive program including field pilot analysis in Wuliwan oil reservoir, a low-permeability reservoir in China, and laboratory experiments was initiated to investigate the displacement mechanism of foam-assisted deoxidized-air flooding. We carried out a series of laboratory experiments of foam-assisted deoxidized-air flooding with different gas–liquid ratios at different water cut stages, while using nuclear magnetic resonance technology to monitor the distribution of crude oil in pores. The results revealed that increasing gas–liquid ratio enhanced oil recovery during the high water cut stage, but reduced it during the middle water cut stage. The differences in oil recovery at different water cut stage appear to be linked to changes of the displacement mechanism. We indeed observed that oil was produced from a wide range of pores at the high water cut stage, but only from the macropores at the middle water cut stage. The field pilot analysis supported our conclusion based on the experimental findings, that foam-assisted deoxidized-air flooding using an appropriate gas–liquid ratio can efficiently lower water cut and enhance oil production at different water cut stages. The combination of laboratory and field pilot tests used here can serve as a template for future studies in other oil reserves.

Comparative Study between Different Oil Production Enhancement Scenarios in an Iraqi Tight Oil Reservoir

This paper presents a comparative study between different oil production enhancement scenarios in the Saadi tight oil reservoir located in the Halfaya Iraqi oil field. The reservoir exhibits poor petrophysical characteristics, including medium pore size, low permeability (reaching zero in some areas), and high porosity of up to 25%. Previous stimulation techniques such as acid fracturing and matrix acidizing have yielded low oil production in this reservoir. Therefore, the feasibility of hydraulic fracturing stimulation and/or horizontal well drilling scenarios was assessed to increase the production rate. While horizontal drilling and hydraulic fracturing can improve well performance, they come with high costs, often accounting for up to 100% of the total well cost. To ensure economically viable flow rates and achieve maximum ultimate oil recovery, a technical and economic comparative study was conducted. The results indicate that hydraulic fracturing offers promising outcomes, with a total oil production of 153,816 Mbbl over 30 years from 25 fractured wells, resulting in a final Net Present Value (NPV) of 3,583.32 MM$. In contrast, the planned two horizontal wells exhibit lower eventual production and NPV compared to the majority of fractured wells. However, the 2000 m lateral section of well HF00Y-S00YH shows a slightly higher NPV. Considering the operational benefits and profitability, hydraulic fracturing should be seriously considered for the further development of the Saadi reservoir. This comparative study provides valuable insights into the most effective approach for enhancing oil production in tight reservoirs like Saadi, balancing the technical feasibility and economic viability of different stimulation scenarios. The findings can guide decision-making processes and contribute to maximizing oil recovery in similar challenging reservoirs.

Nanocomposite of binary colloids in effective CO2 utilization in porous media for enhanced oil production and wettability alteration

Carbon dioxide injection is a renowned enhanced oil recovery method, where the inclusion of a novel material is appreciated via mobility control of injected CO2 during flow through porous and permeable oil reservoirs. Therefore, the combination of nanoparticles and their associated additives is recommended for foam flooding schemes. Thus, this study reports the use of nanocomposites of SiO2 (0.1 – 2 wt%) and TiO2 (0.1 wt%) in promoting CO2 utilization in oil recovery projects. The assessment of a foam emulsion is a crucial and interesting task to understand the basic fundamental of three-phase interactions viz., Crude oil (oil phase), nanocomposites (aqueous phase), and CO2 (gas phase) in the context of foam-emulsion, and was examined via microscopic and rheological characterization. CO2 foam showed temperature tolerance capability and a shear-thinning viscoelastic nature due to the inclusion of nanocomposites. Furthermore, wettability alteration was understood via contact angle measurements between CO2 and nanocomposite. Interestingly, the contact angle was reduced to 39° after the inclusion of 0.1 wt% TiO2 and CO2 in the system. Finally, nanocomposite stabilized CO2 foam demonstrated a total cumulative oil recovery of 78 % at (40 °C), higher than the cumulative oil recovery (70 %) associated with nanocomposite without CO2. The results of this study suggest that CO2 utilization for oil recovery can be enhanced by developing its viscous foam, stabilized by a nanocomposite of SiO2 and TiO2 nanoparticles.

Blue ammonia an attractive pathway to decarbonize conventional ammonia plants

Ammonia is one of the basic ingredients for the fertilizer and mining explosive industries. Conventional ammonia production technologies have a high environmental impact owing to its high carbon dioxide (CO2) emissions. This study evaluates the prospects of blue ammonia through integration of different available technologies within conventional ammonia plants: the Kellogg Braun & Root (KBR) Purifier process, Topsoe and the Linde Ammonia process. Carbon Capture and Sequestration (CCS) and Gas Switching Reforming (GSR) technology are attractive pathways toward blue ammonia due to cost effectiveness and ease of implementation. Blue ammonia technology development has its own challenges to overcome while it has massive advantages and opportunities like blue ammonia utilization as an alternative fuel, availability of pre-existing infrastructure available for storage, enhanced oil production through CO2 pressurization. Given the increasing demand and international ammonia trade, advanced blue ammonia production from different available technologies like CCS & GSR offers an alluring way for natural gas exporting regions to contribute to global decarbonization.

Unveiling the molecular interactions of surface wetting modification in porous medium: A groundbreaking insight into wettability alteration

Recently, discussions have been raised surrounding the cause of changing wettability during brine salinity engineering. The goal of this study is to decode the reason behind wettability changes by introducing a novel approach involves both monovalent (Na+) and divalent (Ca2+) ions. Through molecular dynamics simulations, the study investigates the underlying physiochemical interactions responsible for wettability modification via configuring the amorphous cells and integrated layers. Various metrics were analyzed including the radial distribution function, diffusion coefficient, adsorption energy, mixing energy, solubility parameter, and molecular configurational changes. The results demonstrate the significant influence of oil polarity and the role of sodium ions with a maximum diffusivity of 1.2 × 10−4 cm2/s. Calculations reveal that sodium chloride ions are two orders of magnitude more active than calcium chloride ions. The most notable finding of this study involves the identification of two new mechanisms termed the "brine Prong" and "oil Vortex" effects that play a crucial role in separating oil from the surface and inducing changes in the wetting state. Overall, the results offer significant insights into the fields of engineering water flooding and the interaction between brine, oil, and rock to elucidate the wettability alteration phenomenon in porous medium and secure enhancement of oil production.

Effect of silica-based hybrid nano-surfactant on interfacial tension reduction for enhanced oil recovery

Crude oil production has considerably stabilized economic growth on a global scale. Unfortunately, the difficulties of oil production from a reservoir is being a global concern. Enhanced oil recovery (EOR) is one of the methods employed recently to increase oil production rate. Nanotechnology has been identified as one of the effective EOR techniques employed using nanoparticles (NPs) as a suitable candidates. Altering a reservoir's petrophysical property such as reducing interfacial tension (IFT) between crude oil and other liquids is an essential factor that plays a significant role in EOR. Considering the significant effects shown by silicon dioxide (SiO2) and iron dioxide (Fe2O3) NPs in EOR, the present study is aimed at investigating the influence of Fe2O3-SiO2 hybrid NPs supported with a surfactant on IFT. The hybrid NPs were produced and separately incorporated with surfactants of anionic sodium dodecylbenzene sulfonate (SDBS) and polyvinylpyrrolidone (PVP). The physical and chemical properties of the hybrid NPs were analyzed using X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectroscopies, respectively. According to the results, the XRD pattern of the Fe2O3-SiO2 hybrid NPs displayed a crystalline structure of Fe2O3 NPs. The FTIR spectra of Fe2O3-SiO2 hybrid NPs showed characteristic absorptions of Fe2O3 and SiO2, indicating successful hybrid formation. The viscosity of Fe2O3-SiO2 nanofluids has increased from 0.95 to 1.85 cP. Upon introducing a hybrid nano-surface of SDBS and PVP, the viscosity values increased to 1.95 cP and 1.90 cP, respectively. Moreover, the Fe2O3-SiO2 hybrid NPs has reduced oil/brine/nanofluids IFT from 17.39 mN m−1 to 5.03 mN m−1. Additional reductions were observed when the surfactants were included. Consequently, IFT (mN m−1) was reduced from 17.39 to 3.08 for Fe2O3-SiO2-PVP and from 17.39 to 2.55 for Fe2O3-SiO2-SDBS. The finding of this study can help for a better understanding of the significant effect of silica-based hybrid nano-surfactant for IFT reduction which in turn could enhance oil production.

Static and dynamic evaluation of formation damage due to barium sulfate scale during water injection in carbonate reservoirs

One of the major challenges during water injection into oil reservoirs is mineral scales formation. Barium sulfate is one of the hardest inorganic scales in oil fields and insoluble in chemical solvents. Therefore, in this study, the formation conditions of barium sulfate scale were investigated. The experiments were performed in two parts including static and dynamic compatibility tests and the impact of brines volume ratio, temperature, pH, and salinity of injection water were explored. In addition, the scale formation tendency was simulated and the results were compared with the measured data. The results of static experiments indicated that the maximum amount of barium sulfate scale equals 63 mg/l forms at 90% formation water. Comparing the results of static and dynamic compatibility tests revealed that the increase of pH value increases barium sulfate scale in dynamic tests while having no effect in static experiments. This finding confirms that a different scale formation mechanism prevails in the presence of reservoir rock. The experimental results also approve that the amount of barium sulfate scale decreases by reducing the salinity of injection water, so that by diluting injection water 5 times, the maximum amount of scale decreased 21% and 44% at ambient and reservoir temperatures, respectively. The findings of this study help for better determination of water properties to increase the efficiency of water injection operations, enhance oil production and simultaneously diminish formation damage. Concurrent assessment of static and dynamic tests leads to determining the dominant mechanisms of scale formation in the presence of reservoir rock which helps to select the appropriate remediation methods.

Soil Physical Properties as Influence by Poultry and Cow Dung from Different Housing and Stacking Types Following Telfairia occidentalis (Hook F.) Production

Soil physical properties play significant function in the yield of crop produce. Sustaining food supply of the teeming population depends on the degree of preserving soil physicalproperties, therefore enhancing soil productivity. Experiments were conducted to establish the influence of poultry and cow dung from different housing and stacking types on physical properties of soil following Telfairia occidentalis production in 2017 and 2018. Amendments were applied in both years after which data were analyzed using Analysis of Variance. The experiment reveals that amendments statistically increased soil porosity, moisture content, hydraulic conductivity and therefore reduced bulk density above control in both years. It is concluded that for improved soil physical properties in the study area, bagged poultry manure in palm fronds house (PPB) at 5.4 tha-1 is recommended to farmers.

A hybrid connectionist enhanced oil recovery model with real-time probabilistic risk assessment

An effective enhanced oil recovery (EOR) method requires an evidence-based, data-driven assessment of the impacts of the governing parameters on the rate of oil production. In this research, an innovative and comprehensive approach is developed to analyze the optimization of oil production by carbon dioxide (CO2) injection and associated risks as a function of time in a shale formation reservoir. The data-driven approach is used to perform risk analysis. This study integrates a commercial simulator with a deep learning network and probabilistic method to predict oil production enhancement with the associated risks. The integrated approach presented in this study creates evidence from the Spatio-temporal model based on geological data of the shale formation. The data-driven model uses the long short-term memory (LSTM) network to forecast oil production based on Spatio-temporal datasets. The possible risks are assessed using a dynamic Bayesian network with an early warning index system (EWIS) derived from the data-driven model. The findings of the Spatio-temporal model show that CO2 injection would lead to the maximum oil recovery rate of 22% of the original oil-in-place with associated risks in each cycle of operation. This study confirms that the introduced model can serve as a multifunctional tool for oil production optimization with a clear understanding of associated risks.

Laboratory experiment and field application of chemical assisted steam flooding

ABSTRACT There are serious problems such as steam channeling and low oil-steam ratio when it comes to steam flooding. In order to improve its performance and to enhance oil recovery, foam agents and oil displacement agents are used to enhance the sweep efficiency and the displacement efficiency in steam flooding process. The design, development, and syntheses of high-performance low-cost foam agent and oil displacement agent were put forward in this paper. Evaluation experiment results showed excellent foaming performance and the high-temperature resistance of the foam agent. In addition, good interfacial performance and thermal stability of the oil displacement agent were also observed. The developed system was able to achieve ultra-low interfacial tension under steam flooding conditions. Laboratory experiments of chemical assisted steam flooding showed that the injection of the high-temperature foam agents and oil displacement agents totally enhanced oil recovery of 11.67%. Chemical assisted steam flooding field test has also been carried out in Gudao Zhongerbei Block of Shengli Oilfield. By June 2020, the cumulative oil production in the pilot area was 4.02 × 105 t with the reserve recovery percent of 54.6%, the enhanced oil production was 3.56 × 105 t and the enhanced oil recovery factor was 19.3%.