scholarly journals Geochemical characteristics and localization of heavy oil fields in the Republic of Tatarstan, Russia

Author(s):  
V. A. Sudakov ◽  
◽  
M. S. Shipaeva ◽  
D. K. Nurgaliev ◽  
Z. M. Rizvanova ◽  
...  

High-viscosity oil belong to unconventional sources of hydrocarbon raw materials, the share of which is growing every year. The development of this complex type of raw material requires modern scientific technologies in order to maintain the production of hydrocarbons at the same level. Technologies for the extraction and processing of heavy oil are different from traditional ones. First of all, these deposits are located at a shallow depth, but are classified as difficult to recover due to the complex geological structure and high anomalous oil viscosity. The objective of this work is a deeper understanding of the geochemical composition of heavy oil deposits, taking into account the peculiarities of their geological structure. This is important for the successful development of new and improvement of existing technologies for the extraction and processing of heavy oil and the implementation of the resource potential of heavy oils in the Republic of Tatarstan. Keywords: heavy oil; unconventional oil; biodegradation; GC-MS; geochemical methods.

2021 ◽  
Vol 13 (2) ◽  
pp. 273-279
Author(s):  
Guishan Li ◽  
Xiankang Xin ◽  
Gaoming Yu ◽  
Yadi Gu ◽  
Qiong Wu ◽  
...  

Many studies have shown that heavy oil with high asphaltene content has a yield stress. Coupled with the solid-liquid interaction between porous media and heavy oil, there is a threshold pressure gradient when heavy oil flows in porous media. Meanwhile, some previous research has indicated that the high viscosity of heavy oil is the decisive factor for its threshold pressure gradient. Hence, this concept needs more clarification, especially because its accuracy is questionable. In this research, different oil samples with the same viscosity and also different asphaltene contents heavy oil samples were prepared. The viscosity of the different heavy oil samples was measured. Threshold pressure gradient experiments under different permeabilities and temperatures were also conducted on heavy oils. The results proved that the viscosity was not directly related to threshold pressure gradient of heavy oil. They also suggested that the heavy oil viscosity increased with the increase of asphaltene content. Moreover, the formula of the factors affecting threshold pressure gradient was regressed, and also its applicability was verified. As the temperature and core permeability increase, the threshold pressure gradient was also proven to decrease significantly. Furthermore, it was found that the threshold pressure gradient increased significantly with the increase of asphaltene content. Therefore, the heavy oil threshold pressure gradient could be characterized as a function of temperature, permeability, and asphaltene content. This study provided some theoretical support for the research attempts on the reduction of threshold pressure gradient and also on the effective development of heavy oil reservoirs.


2020 ◽  
Author(s):  
Sudad H Al-Obaidi ◽  
Smirnov VI ◽  
Kamensky IP

High viscosity of heavy oils at reservoir conditions is one of the main causes of the low production rates of producing wells, and sometimes even their complete absence when trying to develop a field on a natural mode. The rheological properties of heavy oil deposits in a wide temperature range were studied in this work. Special attention was paid to the study of viscous and elastic components of oil viscosity as a function of temperature to justify the optimal conditions for the development of heavy oil fields. Heavy oil samples collected from Pechersky oil field (Russia) were used in this research. Dynamic viscosity tests were carried out on the heavy oil of this field. It was noticed that high values of viscous and elastic components of oil viscosity were observed over the entire temperature range. It has also been remarked that the values of oil viscosity components are inversely proportional to the temperature increase.


2015 ◽  
Vol 1 (12) ◽  
Author(s):  
Slobodan Majstorović ◽  
Vladimir Malbašić ◽  
Miodrag Čelebić

Curent situation of raw material base and study of limestone like construction stone deposits in the Republic of Serbian were relatively poorly considered during the last decades, and the main problems are the following: low production capacity fragmentation of production, needs for raw materials homogenization and delivering of standard quality, undeveloped market, the recession of the domestic economy and the economies in the region, the relatively low level of exploration by many deposits, especially lack of knowledge of the occurrence legality for certain types and quality of raw materials and lack of complete quality indicators for raw material, which sometimes causes the utilization of only the highest quality deposit parts.This paper provides an overview of active quarries in the Republic Srpska with exploitation of limestone like technical building stone and present an attempt to determine the basic quantitative and qualitative characteristics of the raw material and the current working conditions at these quarries. The purpose of such a review would be in an effort to create a clearer picture about production, market, social and other aspects of the limestone exploitation in the Republika Srpska and the realistic possibilities of maintaining and developing of these mineral resources utilization, which can certainlybe interesting for the development of many other industries in the Republic Srpska.


2021 ◽  
pp. 201-209
Author(s):  
Kamola Vakhabjanova Raimova ◽  
Nodira Gulomzhanovna Abdulladzhanova ◽  
Farrukh Nazimovich Toshpulatov ◽  
Nurali Azamovich Ergashev ◽  
Alimzhan Davlatbaevich Matchanov

The results of studies of the content of polyphenolic compounds and their antioxidant activity in the Pontic hawthorn plant Crataegus pontica K.Koch., growing in the mountainous regions of the Tashkent region of the Republic of Uzbekistan are presented. The collection of raw materials took place in the spring at the beginning of October 2019 and at the end of April 2020. The conditions for the isolation of polyphenolic compounds were selected under various conditions. It was shown that the optimal content of polyphenols is extracted with 70% acetone, followed by fractionation of the aqueous residue with ethyl acetate and precipitation with hexane. It was shown that in the plants harvested in spring, the amount of polyphenols was 4.28%, and the collected volume was 2.6%, of the air-dry mass of the raw material. Chromatographic methods (BC and TLC) revealed that the composition of plant leaves collected in spring contains more polyphenols than those collected in autumn. This plant contains compounds belonging to the class of flavonols, phenolic acids and flavan-3-ols. Polyphenols were identified by rutin, quercetin, quercetin-3-O-β-galactoside, catechin, and gallic acid by BC and TLC methods. The antioxidant activity of the sum of polyphenolic compounds was studied in the model of lipid peroxidation (LPO) in rat liver mitochondria. It was found that polyphenols have a protective effect on mitochondria, a reduced damaging effect of Fe2+ / ascorbate and antioxidant activity depends on the concentration of the studied polyphenolic substances. The introduction of rutin into the incubation medium in 5 μM medium inhibits LPO processes by 32.0%, and at 10 μM – by 85.9% and in 20 μM – by 96.8%, compared with the control.


Author(s):  
Jorge Luiz Biazussi ◽  
Cristhian Porcel Estrada ◽  
William Monte Verde ◽  
Antonio Carlos Bannwart ◽  
Valdir Estevam ◽  
...  

A notable trend in the realm of oil production in harsh environments is the increasing use of Electrical Submersible Pump (ESP) systems. ESPs have even been used as an artificial-lift method for extracting high-viscosity oils in deep offshore fields. As a way of reducing workover costs, an ESP system may be installed at the well bottom or on the seabed. A critical factor, however, in deep-water production is the low temperature at the seabed. In fact, these low temperatures constitute the main source for many flow-assurance problems, such as the increase in friction losses due to high viscosity. Oil viscosity impacts pump performance, reducing the head and increasing the shaft power. This study investigates the influence of a temperature increase of ultra-heavy oil on ESP performance and the heating effect through a 10-stage ESP. Using several flow rates, tests are performed at four rotational speeds and with four viscosity levels. At each rotational speed curve, researchers keep constant the inlet temperature and viscosity. The study compares the resulting data with a simple heat model developed to estimate the oil outlet temperature as functions of ESP performance parameters. The experimental data is represented by a one-dimensional model that also simulates a 100-stage ESP. The simulations demonstrate that as the oil heat flows through the pump, the pump’s efficiency increases.


2021 ◽  
Vol 143 (7) ◽  
Author(s):  
Ali Alarbah ◽  
Ezeddin Shirif ◽  
Na Jia ◽  
Hamdi Bumraiwha

Abstract Chemical-assisted enhanced oil recovery (EOR) has recently received a great deal of attention as a means of improving the efficiency of oil recovery processes. Producing heavy oil is technically difficult due to its high viscosity and high asphaltene content; therefore, novel recovery techniques are frequently tested and developed. This study contributes to general progress in this area by synthesizing an acidic Ni-Mo-based liquid catalyst (LC) and employing it to improve heavy oil recovery from sand-pack columns for the first time. To understand the mechanisms responsible for improved recovery, the effect of the LC on oil viscosity, density, interfacial tension (IFT), and saturates, aromatics, resin, and asphaltenes (SARA) were assessed. The results show that heavy oil treated with an acidic Ni-Mo-based LC has reduced viscosity and density and that the IFT of oil–water decreased by 7.69 mN/m, from 24.80 mN/m to 17.11 mN/m. These results are specific to the LC employed. The results also indicate that the presence of the LC partially upgrades the structure and group composition of the heavy oil, and sand-pack flooding results show that the LC increased the heavy oil recovery factor by 60.50% of the original oil in place (OOIP). Together, these findings demonstrate that acidic Ni-Mo-based LCs are an effective form of chemical-enhanced EOR and should be considered for wider testing and/or commercial use.


2012 ◽  
Vol 268-270 ◽  
pp. 547-550
Author(s):  
Qing Wang Liu ◽  
Xin Wang ◽  
Zhen Zhong Fan ◽  
Jiao Wang ◽  
Rui Gao ◽  
...  

Liaohe oil field block 58 for Huancai, the efficiency of production of thickened oil is low, and the efficiency of displacement is worse, likely to cause other issues. Researching and developing an type of Heavy Oil Viscosity Reducer for exploiting. The high viscosity of W/O emulsion changed into low viscosity O/W emulsion to facilitate recovery, enhanced oil recovery. Through the experiment determine the viscosity properties of Heavy Oil Viscosity Reducer. The oil/water interfacial tension is lower than 0.0031mN•m-1, salt-resisting is good. The efficiency of viscosity reduction is higher than 90%, and also good at 180°C.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Yong Du ◽  
Guicai Zhang ◽  
Jijiang Ge ◽  
Guanghui Li ◽  
Anzhou Feng

Oil viscosity was studied as an important factor for alkaline flooding based on the mechanism of “water drops” flow. Alkaline flooding for two oil samples with different viscosities but similar acid numbers was compared. Besides, series flooding tests for the same oil sample were conducted at different temperatures and permeabilities. The results of flooding tests indicated that a high tertiary oil recovery could be achieved only in the low-permeability (approximately 500 mD) sandpacks for the low-viscosity heavy oil (Zhuangxi, 390 mPa·s); however, the high-viscosity heavy oil (Chenzhuang, 3450 mPa·s) performed well in both the low- and medium-permeability (approximately 1000 mD) sandpacks. In addition, the results of flooding tests for the same oil at different temperatures also indicated that the oil viscosity put a similar effect on alkaline flooding. Therefore, oil with a high-viscosity is favorable for alkaline flooding. The microscopic flooding test indicated that the water drops produced during alkaline flooding for oils with different viscosities differed significantly in their sizes, which might influence the flow behaviors and therefore the sweep efficiencies of alkaline fluids. This study provides an evidence for the feasibility of the development of high-viscosity heavy oil using alkaline flooding.


2020 ◽  
Vol 17 (34) ◽  
pp. 915-924 ◽  
Author(s):  
Oleg M PRISCHEPA ◽  
Yury V NEFEDOV ◽  
Olga E KOCHNEVA

The estimation of the share of hard-to-extract oil reserves in the deposits of Russia varies by different sources, in a fairly wide range (from 30 to 70 %). Due to the absence of a common approach to their definition, the variety of parameters used to estimate this share and fundamentally different conditions for the development of the groups of reserves classified as hard-to-extract become challanging. A significant share of the proven oil reserves of Russian oil fields - about 34 % (6.3 million tons) - belongs to heavy (oil density more than 0.871 g/cm3) and super-heavy (oil density more than 0.895 g/cm3). In general, the share of high-viscosity and super-highviscosity oils is about 13% (2.4 million tons). The largest share refers to the deposits of three districts. In lowpermeable collectors (permeability less than 0.05 μm2), huge reserves are concentrated – 8.2 million tons or 44.6 % of all oil. Comparison of oil extraction and reserves structure indicates a good correlation for oil extraction from low-permeable collectors in 41.8 % with reserves percentage in 44.6 % as well as a relatively good correlation in super-heavy oil in 13.4% with reserves percentage in 18 % and low rates for super-high-viscosity oil in 1.7% with reserves perecentage in 6 %. Significant proven reserves of high-viscosity oil in Russia indicate the possibility of increasing production with the introduction of modern, existing and proven, technologies under appropriate economic conditions. Full-scale involvement in the development of only the largest deposits of high-viscosity oil would allow the Russian Federation to produce at least 25-30 million tons in the medium term.


2021 ◽  
Author(s):  
S.K. Mustafin ◽  
◽  
A.V. Rasskazov ◽  
◽  

The state and prospects of development of phosphorite ore resources as agrochemical raw materials of the Russian Federation are analyzed. The geological structure, composition of ores and the prospects for forecasting, assessing and integrated development of phosphorite deposits of the South Ural phosphorite basin are characterized.


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