Oil Flow Rate Research Articles

METHOD FOR FORECASTING INCREASE IN LIQUID PRODUCTION FOR OPTIMIZE SELECTION OF CANDIDATES FOR HYDRAULIC FRACTURING

Over the past 20 years, the structure of reserves of Russian oil fields has undergone significant changes: with a general increase in reserves, there has been a significant increase in the share of hard to recover reserves (HTR). In the HTR structure of the Russian Federation, low-permeability and heterogeneous reservoirs are identified as the main subgroup (64 %), in 2022, approximately 30 % of all Russian oil was produced from HTR (166 from 535 million tons). In such reservoirs, to maintain and ensure high levels of oil recovery, a workovers such as hydraulic fracturing (HF) is used.Petroleum production companies have various technical and infrastructal capabilities for the selection of candidate wells for workover. Some oil companies use the support of design institutes and service companies that mining andhave specialized geological software products for monitoring and selection of workovers, others make do with the knowledge and skills of selecting their own specialists. However, due to the development of residual recoverable reserves and the unprofitability of the workover every year to select candidate wells, it is becoming increasingly difficult to select candidate wells. Working out the entire well stock and selection candidate wells using standard techniques takes a huge amount of time for a specialist. The article proposes a solution to the topical issue of optimizing the selection of candidate wells for hydraulic fracturing by predicting the dynamics of production wells based on historical data for various geological conditions. The developed method for forecasting the flow rate of liquid and oil on the basis of the rate of change in reservoir pressure and water cut of the well allows you to predict the flow rate for two years ahead, monthly estimates the possible increase from hydraulic fracturing and allows you to determine the optimal time for repeated or primary hydraulic fracturing at the well. This approach sharply narrows the number of potential candidates from a coupe of hundred to two to three dozen potential candidates.

An Investigation of Thrust Bearing Temperature Rise in Unit 2 Koto Panjang Hydropower Plant

Turbines and generators are the main components of hydropower plants that are supported by several bearings, one of them is the thrust bearing. Thrust bearing unit 2 experienced a temperature rise that exceeded the alarm limit (77℃). This study aims to investigate the temperature rise and provide a solution. The investigation was conducted by visual observation; collating temperature and oil flow rate data; and reviewing the hydropower design. The results showed that the temperature rise was attributed to air (oil vapor) trapped in the lubricant circulation system. Therefore, the lubricant circulation system was modified by adding a pipe to the stayring as an outlet for trapped lubricant vapor. This measure effectively normalized the thrust-bearing temperature and flow rate.

Utilization of machine learning for the estimation of production rates in wells operated by electrical submersible pumps

AbstractIn this study, a neural network model is developed for the prediction of oil flow rates in wells lifted by electrical submersible pumps (ESPs). Three attributes of the model in this work make this study unique. First, the knowledge on the computational cost of models has been presented, a rarity in most neural network models on this subject; second, the models have been explicitly presented, a feature uncommon in published ANN predictive modelling studies; and third, it includes a sensitivity analysis of input variables. The dataset utilized for the model development comprises 275 data points collected from ESP-lifted wells in the Middle East. Statistical evaluation of the model’s performance using the metrics such as mean square error, root mean square error and coefficient of determination demonstrates high predictive accuracy with respective values of 0.0000201861, 0.00449 and 0.999. In order to ascertain the parametric importance of the inputs, Garson’s algorithm was utilized. In this regard, choke size and upstream pressure had the highest influence (19% and 16%, respectively), while casing head pressure had the least effect (4.8%) on oil flow rate. In terms of memory requirements and processing speed for software applications, the model had a memory footprint of 888 bytes and required 191 multiply and accumulate operations to give an output. By utilizing the proposed models, the time-consuming separator tests measurements of flow rate would no longer be necessary and real-time results could be provided in the field. This work would be useful to production engineers who seek a quick and accurate means of estimating oil flow rate from ESP wells in real time.

The use of branched horizontal wells at the Zhanazhol field to increase oil recovery

The research presents an analysis and experiment on horizontal wells of the Zhanazhol field, an analysis of the operation of horizontal wells is carried out. The analysis of the factors affecting the efficiency of oil production by horizontal wells is carried out, experimental and industrial methods of operation are proposed for further implementation of horizontal well technology. The design of the construction of branched horizontal wells has been carried out. The purpose of this work is to substantiate the feasibility of switching to fundamentally new development systems using horizontal wells to increase the flow rate of liquid hydrocarbons using the example of the Zhanazhol field. The results of pilot tests of drilling branched horizontal wells to increase oil recovery at the Zhanazhol field are summarized. At the Zhanazhol field, the maximum capacity of oil reservoirs reaches about 190 m. The average capacity of oil–saturated reservoirs is about 3 m. There are intervals of impermeable interlayers in the productive formation. The thickness of most impermeable layers varies within 5 m. An impenetrable layer with a thickness of about 10 m is spreading widely. This affects the nutrition and energy supplementation of oil reservoirs, resulting in a rapid decrease in oil production and reservoir pressure. For example, the average daily flow rate of oil with a 15 mm fitting is more than 150 tons, but the current flow rate of oil with a 7 mm fitting is 52 tons (horizontal well No. 2407). The technology of drilling branched horizontal wells in certain geological conditions allows: to obtain initial flow rates 10 times higher than the flow rates of conventional wells with an increase in the cost of drilling only 1.5 - 2 times; to ensure accumulated production over 10-15 years of operation 10 times higher at the cost of extracted oil 3-5 times lower than for neighboring conventional wells; to increase the total oil recovery from productive formations by 20-30 percent; to thin the well development grids.

Adjusting for unbalanced phenomena using a hydro-pulser in flowing-gaslift wells

The article deals with the regulation of the gas-liquid mixture movement pattern by creating hydraulic impact pulses during the operation of gaslift wells, keeping it dispersed throughout the lift, reducing energy consumption for its lifting and, consequently, increasing the useful work factor. In this connection, a new high-frequency amplitude hydro-pulsing device has been developed. The device is placed inside tubing strings of gaslift wells, having a swivelling mechanism consisting of a body, two pairs of screens, located at right angles to each other, and wings, mounted on an axis. During well operation as a result of rotation of the blades and opening and closing of the gate the pressure under the blades changes, which causes separation of gas from liquid and creation of rarefaction. As a result, different velocity gradients of different magnitudes are created in different sections of the lifter, and the fluid pressure along the flow path changes discretely, i.e. the fluid acts “compressively” in one section and “tensile” in another cross section. The resulting impulse waves generated by this characteristic pressure distribution are transmitted to the bottomhole zone, ensuring that the gas-liquid mixture is dispersed through the lifter. The device was applied at well № 2187 of “Neft Dashlari” OGED. As a result, correction of unbalanced influences in the well bottomhole zone and lifting elevator was provided, oil flow rate increased from 2 t/day to 3 t/day.

Experiment and Simulation Study on the Cooling Performance of Oil-Cooling PMSM with Hairpin Winding

In this paper, the cooling performance of oil-cooling PMSM with hairpin winding under various oil parameters is analyzed via a simulation and an experiment. The effects of oil jet positions, oil temperatures, and oil flow rates on the cooling performance are analyzed. It is found that increasing the oil temperature in the range of 20 °C to 60 °C, increasing the flow rate of oil jets whose position angle is from 15° to 45°, and increasing the flow rate in the range of 1 L/min to 2 L/min will significantly improve the cooling performance. The apertures of the oil spray ring are optimized using the Taguchi algorithm. The cooling performance is the best when the flow ratio is m(0°):m(15°):m(30°):m(45°):m(60°):m(75°) = 4%:19%:10%:10%:4%:4%. This study provides a guide for the design of the oil-cooling system for the hairpin winding of the PMSM.

Enhancing virtual flow metering on offshore oil platforms through parallel computing and data reconciliation

Technological advances in recent years have facilitated data accessibility and increased computational resources; consequently, more remarkable numerical performances in data analysis and computational tests have become possible. In this context, parallel computing techniques are considered relevant tools in applications necessitating reduced computational time, such as online and real-time monitoring of industrial processes. For these reasons, the present work develops and implements online and real-time monitoring of offshore oil and gas production, using parallel computing to improve the performance of the data reconciliation methodology implemented, which will estimate the virtual flow metering with more reliability and in real time. To achieve this, three optimization methods (DA, L-BFGS-B, and SLSQP) and two approaches of parallelization schemes were considered: (1) parallelization of the simulations of each production well; (2) parallelization of the numerical gradient, performed by the deterministic optimization method. Parallel implementations allowed the reduction of up to 80% (type 1) and up to 89% (type 2) of the simulation time compared to their serial counterparts. Hence, the parallel execution of type 2 exhibited more promising results, while type 1 demonstrated greater adaptability to optimization methods. Finally, the results indicate that parallel computing techniques facilitate data reconciliation in real-time, enabling online monitoring in a much shorter time and more accurately than achieved with similar sequential procedures. Moreover, the implemented methodology has proven effective for virtual flow metering of each well’s flow rates of oil, water, and gas. In this context, parallelism techniques present the potential for developing the global monitoring of the virtual flow meters for real-time oil, water, and gas flow rates in each well.

Investigation of the potential of application Frac-Pack technology as a solution to the problem of sand control and increasing the production of high-viscosity oils at M field

Background: In this paper, the potential of applying hydraulic fracturing with the installation of a gravel pack in the Cretaceous horizons of the M field is investigated. The relevance of the work is due to the fact that today the selection of optimal technologies to increase the rate of oil production from the Cretaceous deposits an open platform for proposals and discussions. The low oil recovery coefficient is due to the existing restrictions on the oil production process: high oil viscosity, the presence of gas and water-oil zones, abundant sand production in a poorly cemented reservoir.
 Aim: The purpose of the work is to study the potential application of Frac-Pack technology in the wells of the M field.
 Materials and methods: In order to assess the potential of using Frac-Pack in a special FracPro software, a model of geomechanical and filtration properties of the formation was developed and a simulation of the design with various injection parameters was performed. Based on the results of laboratory studies of the content of mechanical impurities in liquids sampled at the M field, the diameter of the proppant and the flow section of the filter were determined.
 Results: As a result of the study, hydraulic fracturing was simulated for a well from a sample of potential candidates, the oil flow rate was calculated after the application of the proposed technology, materials for the implementation of Frac-Pack technology were selected based on laboratory studies.
 Conclusion: The study showed that the proposed pre-development strategy is the most optimal for shallow wells of the M field, as it is aimed not only at solving the problem of combating the removal of mechanical impurities, but also increasing oil production.

Piezo-viscous-polar lubrication of hybrid conical journal bearing with slip boundary conditions

Various anti-wear and anti-corrosion coatings are applied on the surface of journal and bearing to maximise service life of a bearing system. These coatings influence the wettability of surfaces consequently causes velocity slip phenomena in the bearing system. This article addresses a novel investigation to examine the influences of velocity slip and PVP (Piezo-viscous-polar) lubrication on multirecessed hybrid conical journal bearing (MHCJB). For various cases of velocity slip, novel forms of Reynolds equation are derived and solved numerically by using FEM. The results reveal that velocity slip severely affects the generation of oil film pressure. Consequently, it deteriorates the bearing characteristics viz. load carrying capacity, oil flow rate and rotordynamic coefficients. Further, PVP lubricant offers substantial enhancement in bearing characteristics.

Intense field dielectric purification of oil droplets in machining buildings

Intense field dielectric (IFD) exhibits environmental friendliness and high efficiency in particle purification, with varying efficiencies based on the physical properties of the particles. However, limited research has been conducted on the application of IFD for purifying indoor air polluted by oil droplets. This study experimentally investigated the efficacy of IFD in purifying machining-generated oil droplets. The primary objectives were to clarify the advantages, applicability, and recommended parameters for the purification of oil droplets using IFDs. The results indicate that the efficiency and pressure drop of using IFD for oil droplet purification can reach three times and half, respectively, compared to the conventional low-resistance filter (G4 filter). Furthermore, a formula was derived through fitting to describe the efficiency and pressure drop of IFD for oil droplet purification. IFD achieved a purification efficiency of over 90 % with a deviation of less than 8 % for oil droplet diameters greater than 5.0 μm or airflow velocities below 0.5 m/s. IFD exhibited over 4 % and 2 % higher purification efficiency for atomized and soluble oil droplets, respectively, in comparison to evaporated-condensed and straight oil droplets. At airflow velocities below 1.0 m/s, IFD demonstrated purification efficiencies exceeding 80 % for oil droplets generated by evaporation-condensation and over 90 % for those generated by atomization. Increasing the atomized oil flow rate from 20 to 60 ml/h resulted in corresponding 15 % improvement in purification efficiency, attributed to the larger droplet diameters. This study laid the groundwork for effective utilization of IFDs in the context of machining-generated oil droplet purification.

Integrated model "reservoir-well" based on D-CRMP

The active use of integrated modeling in reservoir engineering of oil fields has led to research to overcome the problems of its practical application. Typically, a 3D hydrodynamic model is used as a component characterizing the fluid flow in the reservoir. The downsides of the model are high computational complexity and low reliability of the initial data. Therefore, the objectives of the study are to construct an integrated reservoir-well model that does not have these drawbacks and to verify its adequacy. The article presents an integrated model for fast decision-making in the development of oil fields, as well as for analysis of the characteristics of the inter-well space, which doesn't require prior information about the reservoir. The integrated model is based on a representation of the analytical capacitance-resistance model (CRM), which considers shutdown periods of production wells. Oil flow rates are calculated using the Koval method. The pressure distribution in wells is calculated using a correlation similar to that used in the tNavigator software. A comparison was made between the calculation results obtained using the integrated model based on D-CRMP and the calculations in the tNavigator.

АНАЛИЗ ПОКАЗАТЕЛЕЙ НАДЕЖНОСТИ ЭЛЕМЕНТОВ СИСТЕМЫ ВЕРХНЕГО ПРИВОДА ПРИ ЭКСПЛУАТАЦИИ НА МЕСТОРОЖДЕНИЯХ ЗАПАДНОЙ СИБИРИ

Oil and gas companies carry out routine and major repairs of wells using mobile drilling complexes equipped with top drive systems (TDS) in order to increase the fl ow rate of oil and gas wells. Statistical data on the operation of more than sixty TDSs in the fi elds of Western Siberia were collected and analyzed. The TDS’s main reliability indicators, such as the probability of failure-free operation and the failure rate, were calculated. The fi ndings can be used to improve drilling equipment maintenance and repair procedures. The insuf fi cient level of reliability of the TDS elements, along with intense operating conditions in the fi elds of Western Siberia, causes failures and halts the entire technological process of well repair, necessitating the need for repair and renewal operations. The fi rst priority of oil and gas companies lies in increasing the TDS reliability based on the high requirements for the reliability of drilling equipment operated at hazardous production facilities, as well as driven by the purpose of continuous operation on routine and major repairs of wells.

Efficience of multistage fracturing in horizontal wells of the Kashiro-Podolsk deposits

The article is devoted to the methods of extracting reserves from complex carbonate reservoirs based on a complex of geological and technical measures. The parameters influencing the technological efficiency and the increase in oil production are analyzed. These include geological and filtration-capacitive heterogeneity, as well as technological parameters. The division of carbonate rocks into petrotypes is considered in order to assess their impact on input technological indicators – water content, oil flow rate. Geological conditions have been studied, as well as geological and technical parameters that have a significant impact on oil production and reservoir flooding during the multistage acid fracturing. The studied relationships allow for a detailed analysis of the success of events and a detailed approach to the selection of candidate wells.

Coordinated control strategy for concentrated solar power systems considering active defocusing

With an increasing proportion of renewable energy in the energy structure, concentrated solar power plants are required to respond rapidly to automatic generation control (AGC) commands, to ensure the grid stability when connected to the grid. Active defocusing affects the collecting capacity of the collector, which not only serves as a safety protection measure for system operation, but also improves the system load shedding rate and provides the possibility of system participation in the auxiliary service of grid frequency regulation. In this paper, a coordinated control strategy for parabolic through concentrated solar power (PTCSP) system considering active defocusing of collector is proposed. The coordinated controller utilizes four manipulated variables, including mass flow rate of heat transfer oil in the collector, active defocusing angle, mass flow rate of molten salt in the heat storage system, and main steam valve opening, to regulate three output variables, namely, collector outlet temperature, turbine power, and main steam pressure. By integrating the steady-state defocusing angle in the optimization function, the controller can utilize the extra control freedom degree to improve the control effect, and ensure that the final steady-state defocusing angle to be small, which reduces the unnecessary heat collection loss. The proposed control strategy improves the power response rate and also avoids excessive heat transfer oil temperature and main steam pressure. In the simulations featuring two 20% variations in load target value, the root mean square error of the outlet temperature of the collectors is reduced by 0.094, and the heat storage is reduced by 0.99 MWh.

ВЛИЯНИЕ ГИПЕРРАЗВЕТВЛЕННОГО ПОЛИМЕРА НА ЗНАЧЕНИЯ ВЯЗКОСТИ ДЛЯ ТРУБОПРОВОДНОЙ ПЕРЕКАЧКИ ЖИДКИХ УГЛЕВОДОРОДОВ

The article presents the results of studies of the industrial hyperbranched polymer Boltorn W300 on the values of the dynamic viscosity of oil from Yakut fields in various concentrations and in different temperature ranges from 5 to 25 ° C in increments of 5 ° C, which can positively influence the processes of pipeline transportation of oils in conditions of complex rheological parameters of pipeline operation networks. A preliminary analysis of oil for physical and chemical properties was carried out and the rheological characteristics of the base oil were studied. It has been established that, according to the results of structural group analysis, the chemical composition of the oil is paraffinic. Using a rotational viscometer, the dynamic viscosity of the shear rate of an oil system containing an additive component in concentrations of 10, 30, 50, 80 and 100 ppm. It was revealed that the effectiveness of the hyperbranched polymer Boltorn W300 is observed only at low temperatures (below 10 0C); an increase in the effectiveness of the hyperbranched polymer Boltorn W300 from an increase in the concentration of the polymer additive in the oil system was also revealed. The most effective additive concentration in this study is 100 ppm, where the viscosity index is reduced by 40,7 %. The greatest effectiveness of the hyperbranched polymer Boltorn W300 in reducing dynamic viscosity and improving rheological properties is observed in the region of low shear rates - up to 3 s-1, which can be preliminarily assessed as a positive quality for use on pipelines for pumping oil media during the pipeline commissioning period, at which low shear rates are observed. shear rates and low oil flow rates.

ФОРМИРОВАНИЕ И РЕДУКЦИЯ БАЗЫ ЗНАНИЙ ДЛЯ ОЦЕНКИ ЦЕЛЕСООБРАЗНОСТИ БУРЕНИЯ СКВАЖИН НА НЕФТЯНЫХ МЕСТОРОЖДЕНИЯХ

The article discusses the issues of forming and reducing a fuzzy knowledge base designed to assess the feasibility of drilling wells in oil fields as part of a decision support system. The initial knowledge base was formed using a specially developed software package that implements neuro-fuzzy modeling technology based on a group of fuzzy neural networks. To train them and form a knowledge base, initial data were required that described the dependence of the influence of the characteristics of producing wells on their efficiency in terms of the production rate of oil produced. The initial data for the analysis of 3187 records were presented for 46 oil field objects with carbonate reservoirs. Each record was characterized by the values of the input parameters “absolute rock permeability”, “rock porosity”, “average flow rate of neighboring wells” and “minimum water cut of neighboring wells”. The output parameter determined the efficiency of the well as the average oil flow rate for the first 3 years of operation. When training a team of 5 fuzzy neural networks, 5 gradations of input parameters were selected. The total number of fuzzy rules in the original knowledge base was 319. To assess its classification ability, the values of the Accuracy, Precision, Recall and F1-Score metrics were calculated. To reduce the knowledge base, a specially developed software package was used that implements 2 stages of genetic optimization: structural-parametric transformations of the fuzzy rules of the original knowledge base to obtain an intermediate knowledge base and minimizing the composition of the fuzzy rules of the intermediate knowledge base to obtain the desired (reduced) knowledge base. As a result of the reduction, the quantitative composition of knowledge bases, as well as the values of classification quality metrics, changed. The number of rules in the intermediate knowledge base was 131, and in the reduced one - 33. The overall reduction in the volume of the knowledge base was 89.66%. After the 1st stage of reduction, the values of the Accuracy, Precision, Recall and F1-Score metrics on the test data set increased, respectively, by 7.88%, 6.8%, 0.34% and 0.53%. After the 2nd stage of reduction, the overall increase in the values of these metrics was, respectively, 9.02%, 7.55%, 1.58% and 1.68%. The results obtained were tested at Tatneft and used to form and optimize the knowledge base when developing a decision support system for assessing the feasibility of drilling wells in oil fields.

Comparison of the effectiveness of flow diverting technologies with hydrodynamic oil recovery improvement methods

In this paper, two methods of increasing the efficiency of oil recovery at the final stage of development are compared - the distribution of filtration flows using various compositions and technologies, as well as changing the operating mode of the injection well to prevent the movement of the injected liquid at the most flushed intervals. Based on the use of various hydrodynamic, geological-physical and geological-statistical models, calculations related to the identification of the distribution trend of the injected liquid in a porous medium have been carried out. Using the calculation of the required indicators on various simulators, curves for the distribution of oil flow rates and product water content were constructed in dynamics depending on the permeability of reservoirs. Based on the results obtained, it is concluded that with the effective displacement of residual oil reserves within the framework of changing the dynamics of the injection well, it is necessary only to use the method of distribution of filtration flows with a decrease in productivity.

Моделирование работы самотечных участков нефтепровода

In the modern world it is difficult to underestimate the role of oil in the economy of each country. It is a raw material for chemical processing, an energy carrier with a long history of production and transportation. The prevailing volume is delivered overland by pipeline transportation due to high transportation speed, flow rate and the possibility of regulating pumping stops. However, the main difficulty in pipeline operation is the selection of the optimal pumping mode. Due to terrain peculiarities, as well as variable oil flow rates along the length of the pipeline route, gravity pumping sections occur. Operation of the oil pipeline with these sections is complicated due to the change of pumping from single-phase to two-phase and the influence of vapor-air mixture on oil pumping indicators. In this paper the main indicators of gravity mode of oil pumping are considered, numerical modeling methods are applied to derive a new formula that considers the influence of gas mixture on the transported oil flow; a 3D model of the stand is proposed, on which this mathematical model will be verified, as well as the invented instruments (devices) for determining the coefficient of oil pipeline filling will be tested.

Modeling and semi-analytical solution for immiscible and miscible fingers formation during enhanced oil recovery

ABSTRACT The fingering phenomenon arises during the secondary and tertiary oil recovery processes when injected fluid (water, gases, nano/biomaterials, or polymer particles) shoots through a porous medium at a relative speed. Oil recovery is influenced by various factors including the fluid type, capillary pressure, permeability, and porous material structure. All these elements play crucial roles in determining the success and efficiency of the oil recovery process. Many scientists have debated the fingering phenomenon from different perspectives. Here, we developed mathematical models with and without considering mass flow rates of oil and water for an inclined oil layer flowing through a homogenous porous medium to generate immiscible fingers. Furthermore, a mathematical model of miscible viscous finger formation with carbonated water injection (flooding) during the enhanced oil recovery process (EOR) has been analyzed in this paper. To solve each of these mathematical models, we used the recently developed approach known as the Method of Directly Defining the inverse Mapping (MDDiM). We found approximate solutions to the nonlinear partial differential equations (PDEs), which describe each modeling of the fingering phenomenon in a homogeneous porous medium by incorporating gravitational effects for several types of flooding and discussed the effects of the saturation rate.

FACTORS AFFECTING THE PERFORMANCE OF HORIZONTAL OIL WELLS OF THE KARACHAGANAK FIELD

The article is devoted to carrying out calculations of the productivity of a horizontal oil well by various methods, comparing the results of calculations and developing recommendations for determining the flow rate of oil, taking into account the influence of other previously unexplored factors. The obtained results of calculating the flow rates of horizontal wells at different reservoir thicknesses h, the length of the horizontal trunk L, the absolute permeability k, depression on the reservoir ΔP in which calculated by the method of Yu.P. Borisov, S.D Joshi, F.M. Giger, G.I. Renard, J.M. Dupug, Z.S. Aliyev, V.V. Sheremet.