Table of contents

Preface

ThEOR2018 aims to bring together key researchers and professionals from the industry, R&D centers and academic institutes to share experiences, perspectives, insights and the latest developments in thermal methods for EOR. The workshop's program contains one-day training courses and three days of plenary and keynote lectures, technical and poster sessions on cutting edge issues related to the petroleum industry. At the same time, we try to keep the balance between traditional and emerging fields, fundamentals and applications, modeling and experiment, academic interests and industry needs. The Workshop was be held in Southwest Petroleum University, Chengdu, P.R. China on October 15-19, 2018."

All papers published in this volume of IOP Conference Series: Earth and Environmental Science have been peer reviewed through processes administered by the proceedings Editors. Reviews were conducted by expert referees to the professional and scientific standards expected of a proceedings journal published by IOP Publishing.

Fluid seals are the most important element of oil fields, because they prevent the spread and dispersion of hydrocarbons and contribute to the preservation of deposits. The role of the fluid seals increases in the later stages of oil field development, especially when using thermal methods of intensification. As a result, changes in the mechanical, mineralogical, and lithological properties of the fluid seal rocks can occur. The deposits of natural bitumen of the Volga-Ural petroleum province are a complex geological and geochemical object. The degree of preservation of hydrocarbon deposits is determined by the filtration characteristics of the fluid seal. The composition of the fluid seals is represented by dense clay components of the rock. The use of thermal or steam-thermal methods of exposure to hydrocarbon reservoirs, primarily affects the minerals-indicators (clay minerals of cement collectors). The results of thermal effects on the reservoir can lead to changes in the material composition, parameters of porosity and permeability of the fluid seal rocks: the clay component is destroyed with the active participation of organic matter.

The actual task in the fuel and energy sector is the conversation of alkanes, which are a part of the light hydrocarbon fractions of petroleum, into the top requested chemical feedstock. Perspective technologies are the technologies ofther olefinic and aromatic hydrocarbons production which are used as feedstock for the synthesis of valuable chemical products with a high discount of the market price from the cost of production. A study of the n-hexane conversion over a stationary layer of a catalytic system based on γ-Al₂O₃ containing Pt, Re, In, Ti at 400 and 450 °C and a rate of volume flow of 4 h⁻¹ was performed. The specific surface of the catalytic system is more than 190 m²/g. It was revealed that an increase in the catalysis temperature by 50 °C leads to an increase in both the conversion of n-hexane by a factor of 2 and the methyl-substituted benzenes selectivity to 33.2 wt %. The catalytic system did not change before and after the experiments according to X-ray fluorescence and X-ray spectral analyzes, the elemental and phase composition.

During the work composition and properties of Ni-Al mixed oxides samples were investigated. These oxides were obtained from Ni-Al layered double hydroxide using thermal and hydrothermal methods. Catalytic cracking of a model mixture of alkanes was carried out in the presence of Ni-Al mixed oxides samples. Gas chromatography, chromatography-mass spectrometry, and IR-spectroscopy were used for the analysis of gaseous and liquid products. X-ray structural, X-ray fluorescence, IR-Fourier spectrometry, the specific surface analyzer, particle size analyzer, microphotographic analysis were used for the analysis of the composition and properties of catalytic systems. According to X-ray structural and X-ray fluorescence analyzes, the composition of the supporting structure of the catalyst Ni-Al mixed oxide did not change after catalysis. The content of their low-boiling homologs increases, alkanes of a branched structure is formed in the products of n-alkanes cracking in the presence of the obtained mixed Ni-Al oxide.

Development of resources of heavy hydrocarbons is possible due to the evolution of technologies of their processing, including through the intensification of technological methods implemented in the field of their production at oil treatment plants. The research is devoted to the creation of a method of refining heavy hydrocarbon raw materials based on multiple increases in the working surface of the liquid phase during its intensive evaporation. The intensification of the single evaporation process is based on the fact that the heated raw material is sprayed in a hollow apparatus with the division of the final product into a distillate and a bottomless residue. Due to the spraying of raw materials, the interface of the phases is greatly increased, the supramolecular convective mass transfer becomes so large that it is comparable to the diffusion transfer. The aim of the study is to obtain the data necessary to create energy-saving technologies for the separation of heavy hydrocarbon resources. The paper discusses the possibility of improving the process of single evaporation of heavy oil due to the development of the working surface of the liquid phase, which is realized by spraying the latter. The process of crushing oil into droplets is considered in unity and interrelation with all phenomena occurring in the apparatus. The phase boundary increases several times, which makes supramolecular convective mass transfer comparable to diffusive transfer, which allowed for the separation of heavy oil to increase the distillate selection more than 3 times, with the weighting of the residual product.

Depositions of the Domanic type in the territory of Tatarstan are stratigraphically associated with carbonate-siliceous deposits of the Upper Devonian part of the section. These deposits, enriched with organic matter, are characterized by the ability to generate liquid and gaseous hydrocarbons and accumulate them in the form of deposits of unconventional type. In this paper, the results of geochemical studies of rock samples from the depth interval 1705-1728 m of the Semi-Bug-Buregian deposits of the Berezovskaya area of the Romashkino oil field are presented. It is shown that the rocks, in spite of the narrow core sampling interval, differ in the content of quartz and calcite, as well as in the admixture of minerals such as muscovite, pyrite and albite. The content of organic matter according to thermal analysis data varies from 1.97 to 35.48 %, a significant part of which falls on an insoluble organic matter - kerogen. The influence of hydrothermal processes on the production capacity of the organic matter of these rocks is shown to generate hydrocarbons at temperatures of 200, 250, 300 and 350°C in a carbon dioxide medium. The yield and quality of the products obtained is estimated. The results of the research give grounds to believe that: firstly, the rocks of the Berezovskaya area of the Romashkino oil field have not fully realized their oil potential and the hydrothermal effect on them contributes to the thermal maturation of organic matter in the rock; second, at these temperatures, more intensive recovery of free hydrocarbons from the rock occurs. Thus, the hydrocarbon potential of the house rock is determined by the composition and content of liquid bituminous components that are in a free state in the rock, as well as the products of destruction of tar-asphaltene substances and macromolecules of insoluble kerogen and, consequently, it can be successfully realized with further optimization of hydrothermal processes directed to increase the quantity and improve the quality of the extracted fluids.

For many years, enhancing heavy crude oil recovery has been widely considered as an important challenge for many researchers who, as a result, proposed the use of catalytic systems as an alternative way to solve it. Among a wide range of catalytic systems, nano-sized catalysts based on transition metals in several studies showed an effective catalytic activity and high diffusion through reservoir rock porous media during the process of oil aquathermolysis. This paper aims to widen our current knowledge about catalytic oil aquathermolysis by studying the ability of using catalysts based on iron oxide (II, III) nanoparticles combined with hydrogen donor in order to improve heavy oil hydrocarbon content and to reduce its viscosity. Therefore, we performed oil aquathermolysis at 200 and 300°C for 24 hours. In the case of the catalytic process, catalyst content was 0.3 wt % and hydrogen donor content was 3 wt %. As result, SARA analysis of upgraded oil showed a decrease in the resins content by 25 % and an increase in aromatic fractions due to the destruction of C-S bonds compared to the initial oil. Despite the fact that asphaltenes content remained practically constant, their molecular weight decreased. The evidence from this study suggests that heavy oil viscosity decreases by more than 67 % in the presence of nanoparticles based on iron oxide (II, III).

This work is devoted to selection of acidic compositions for use in the process of acid fracturing of carbonate oilfields. The selection is based on the stability of the compositions and their compatibility with oil and corrosion influence on oilfield equipment. The object of research was highly viscous bituminous oil and carbonate rock of Tatarstan Republic (Russian Federation). The object of research was oil and carbonate rock samples from the Vereian horizon of the Vishnevo-Polyanskoe oil field, which is characterized by oil containing in carbonate rocks. The chosen oil can be pertained to highly viscous bituminous oil according to its density and viscosity, what makes the process of its extraction from oil formations complicated. As the result there were selected two acid compositions which contained hydrochloric acid 15 wt %, demulsifier, dispersant, iron converter (for Fe³⁺ 2000 and 5000 ppm concentration) and corrosion inhibitor. The effectiveness degree of selected compositions was also demonstrated.

Structural characterization of asphaltenes in complex systems is in the focus of scientific and industrial interests since many years. Asphaltenes isolated from the high-viscous Ashal'cha oil (2500 mPa·s) were studied. Five asphaltene fractions were obtained by stepwise extraction with an alcohol-benzene solvent with different alcohol contents after precipitating the asphaltenes from the oil with hot isooctane. Redistribution of paramagnetic centers between the fractions of asphaltenes is revealed by electron paramagentic resonance (EPR) while no significant changes in EPR spectral parameters are found. The results can be used for tracking the asphatenes formation as well as following the changes of their supramolecular structure.

Currently, the world is intensively exploring the possibility of obtaining highly active catalysts for hydrothermal processing of high-viscosity oils through the synthesis of new carriers, optimization of the composition, structural parameters in order to increase the degree of conversion of high-molecular hydrocarbons. The work is devoted to the study of the composition and properties of a montmorillonite intercalated with γ-Al₁₃O₄(OH)₂₄(OH₂)₁₁(OH)₆⁺ and containing catalytically active pillars agents γ-Al₂O₃ in the reactions of hydrothermal transformation of high-viscosity oils. Experiments conducted in a catalytic laboratory setup in a flow-down reactor with a stationary layer of pillared montmorillonite at a temperature above 450 °C and a pressure of not more than 0.5 MPa showed an increase in the conversion of high molecular weight n-alkanes 1.3 times, with the formation of low-boiling n-alkanes and alkanes branched structure.

The experimental results and the character of the heavy oil transformation in a vapor-air medium, at temperatures and pressures providing the water availability in superheated steam state, in addition in subcritical and supercritical states are shown. Due to various thermodynamic conditions, there was the detection that water reactivity to the transformation of heavy oil hydrocarbon components is different. It was proved that supercritical water ensures the vastest yield of light fractions, boiling point of which is above 350 °C

The paper reveals the distinctive features of the change in the composition heavy oils of various types and of natural bitumen - asphaltite from the sandstones of the Permian sediments of the Spiridonovsky field in the territory of Tatarstan, in model experiments at a temperature of 250°C, characteristic for steam-thermal impact on the formation, and the pressure in the system of not more than 2 MPa. The choice of low pressure is due to the fact that bituminous rocks in the Permian sediments occur at relatively shallow depths in the near-surface deposits of the sedimentary strata, which necessitates the development of special technologies for their extraction. The experiments used natural iron oxide - hematite. As a part of the products of asphaltite conversion under the influence of hydrothermal-catalytic factors, the content of hydrocarbons almost 4-fold, the content of alcohol-benzene resins and asphaltenes decreases. The content of benzene resins increases somewhat. The composition of asphaltite proved to be less stable than of heavy oils from age-old sediments, apparently due to special conditions for the formation of its composition in natural conditions under the influence of secondary low-temperature biochemical processes that led to the accumulation of thermally unstable resinous-asphaltene components. Compared with the original asphaltite, in the products of the experiment, the content of alkanes of composition C₁₀-C₃₀ substantially increases with an obvious predominance of homologues with an even number of carbon atoms in the molecule. The product is characterized by a lesser degree of aromaticity and content of sulfoxide groups. The results of the studies showed the possibility of upgrading the composition of solid bitumen - asphaltite in in situ conversion by diluting its composition with lighter newly formed hydrocarbons, due to the destruction of its high molecular weight components.

Increasing steam-thermal methods efficiency for heavy using various catalysts is generating considerable interest in scientific research all over the world. Thus, it is worth to optimize catalyst effectiveness during their in-situ formation from oil soluble precursors using different transition metals. In this paper, a physical simulation of heavy oil catalytic aquathermolysis from the Ashalchinskoye field was carried out. The process was carried out in the presence of a hydrogen donor and a mixture of oil-soluble iron and cobalt metal tallate (1:1 weight ratio) at temperatures 250 °C and different exposure time (6 and 24 h). It was found that the most effective conditions for the thermal conversion of the oil under study are a temperature of 250 °C at 24 hours. In this case, a significant decrease in the proportion of high molecular weight components, mainly resins (by 39 %) and viscosity (about 45 %) occurs due to the course of destructive processes. At the same time, GCMS analysis of the aromatic oil fraction showed that an increase in time promotes the redistribution of mono- and polyaromatic structures.

Heavy oil in-situ combustion process has many benefits among other thermal enhancing oil recovery methods. However, its application is still a complex task due to the irregular propagation of combustion front in the reservoir and its early breaking down. Recent finding regarding in-situ combustion development have led to use catalysts based on transition metals in order to stabilize and enhance combustion front flow. Transition metals was chosen rather than other types of catalysts because of their practical, feasible and economic impact in a wide range of industrial processes.

Current solutions to catalytic in-situ combustion are inconsistent with their application in real fields due the problems associated to the injection of catalysts in the reservoir from one side and to the high cost that can be generated from the use of certain type of catalysts. In this context, we studied the effect of copper and manganese tallates in different metal ratios on the oxidation of heavy oil by applying various physical and physical-chemical methods. As a result, we have obtained accurate results demonstrating the potential effect of Cu-Mn tallates in stabilizing combustion front during high temperature oxidation reactions.

The asphaltene fractions from initial crude oil of Ashal'cha field were extracted for the further investigation. Moreover, the non-catalytic and catalytic products of aquathermolysis in the presence of cobalt-containing catalyst precursor and hydrogen donor dependent on treatment time were studied. Five fractions of asphaltenes and carben-carboids were obtained by batch extraction method. The catalytic hydrothermal treatment revealed a redistribution of group composition and the reduction of resins and asphaltenes because of destructive hydrogenation processes mainly on carbon – heteroatom bonds. In this paper, we have obtained comprehensive results regarding the redistribution between the asphaltene fractions (extracted by solvents with various compositions) due to catalytic aquathermolysis.

The purpose of the work is to identify patterns of transformation of high-molecular components of super-heavy oil by hydrothermal-catalytic processes, namely in the presence of a supercritical state of water. The regularities of changes of the component, structural-group, fractional and elemental compositions of heavy oil during the conversion under the above conditions were established, rheological characteristics of the initial crude oil and converted oil were studied as well. As a result of carrying out aquathermolysis in the supercritical water environment and in the presence of carbonaceous substances, the high-molecular weight components of the initial crude oil were degraded with the formation of light distillate fractions, which were scarcely present in the initial crude oil.

Structural characterization of asphaltenes in complex systems such as native hydrocarbons is in the focus of scientific and industrial interests since many years. Various analytical tools and approaches are used for that. We present the results of our study of asphaltene fractions A1 and A2 with the predominantly "island" type and "archipelago" type asphaltene molecules by conventional and pulsed electron paramagnetic resonance (EPR) at X-band (9 GHz) and W-band (95 GHz) with aim to expand the abilities of EPR technique for asphaltene characterization. Shift to the higher frequencies allows to separate spectrally the contributions from paramagnetic complexes of different origin, define the EPR parameters more accurately comparing to the conventional X-band EPR. Application of pulsed techniques allows (at least partially) to separate the radicals in time domain. Features of the obtained spectra are described. Electronic relaxation times are found to be different for stable "free" radical for A1 and A2 fractions. We suggest that the obtained results can be used for investigation of various petroleum systems.

We report the observation of the conventional and pulsed electron paramagnetic resonance (EPR), electron-nuclear double resonance (ENDOR) spectra from ¹⁹F and ⁷Li nuclei on impurity Nd³⁺ ions in LiYF₄ crystal doped with Nd³⁺ ions in parallel orientation at microwave frequency of ν ≈ 95 GHz (W-band). The resolved structure from the nearby and remote nuclei in spectra is observed. The outcome shows that LiYF₄:Nd³⁺ system can be exploited as a convenient matrix for performing spin manipulations and adjusting quantum computation protocols while ENDOR technique is usable for the investigation of electron-nuclear interaction with the nuclei of the system.

Overhauser dynamic nuclear polarization (ODNP) in solutions of various paramagnetic complexes has been studied for 60 years, but only in recent years has found applications of broad interest to biophysical and biomedical sciences, for the investigation of soft materials and biomolecules. Relatively few aplications are focused on the ODNP in petroleum dispersed systems (PDS) like oils, bitumen, their fractions and solutions. This work present a short review of the ODNP studies of PDS with aim to introduce the basic concepts and key values for the effective petroleum ODNP in low and high magnetic fields. Experimental results obtained in our Laboratory by using home-made spectrometer are included. The study can be used for designing ODNP spectrometers, proton precession magnetometers for geological and geophysical exploration, investigation of supramolecular organisation of PDS and their components.

Pure and substituted hydroxyapatites (Ca₁₀(PO₄)₆(OH)₂, HAp) have been recently gaining special importance in catalysis for selective reactions where the synergetic functioning of acid–base active site pair facilitates the molecular transformations. Transition to the nanostructured HAp materials and ion incorporation can cause lattice distortions and influence physicochemical properties of HAp. We have investigated powders of HAp synthesized by wet techniques from the nitrogen-containing solutions with the average particle sizes of 30 (nanosized) and 1000 nm (microsized) with pulsed electron paramagnetic resonance (EPR). Electronic relaxation times (T_1e) for the stable impurity paramagnetic NO₃²⁻ centers were measured in the temperature range of 10-300 K. It is revealed that T_1e shortens with the size reduction of factor two in the whole temperature range. The results are discussed in the framework of the modified Debye model taking into account non-Debye HAp phonon density. The obtained results show the feasibility of pulsed EPR techniques for characterization HAp based materials.

In this work, the in-situ upgrading of heavy oil from Tatarstan oilfield using steam and copper stearate as a catalyst at 250 °C and 35 bar for 24 hours was studied in stainless-steel reactor. Changes in the density/API gravity, viscosity, chemical composition (SARA-analysis), elemental composition and structure (FTIR-spectroscopy) of heavy oil before and after conversion were determined. Generally, we can summarize, that the content of resins and asphaltenes as well as the average molecular weight of heavy oil were reduced after conversion process. Whereas, amount of saturated and aromatic hydrocarbons was increased due to the destruction of its high molecular weight components. Also, irreversible decrease of viscosity was fixed.

Influence of pressure, temperature and the nature of gas on the viscosity of heavy crude oil from the Tatarstan field was studied using rheology method (rheometer MCR 302). The effect of temperature from 25 to 125 °C and pressure from 0.1 to 12.5 MPa on crude oil viscosity was investigated. It was found that an increase in temperature of 125 °C leads to a decrease of viscosity by 8 times. At the same time, an increase of pressure up to 10 MPa leads to an increase in viscosity by 38% at low temperatures. Also the influence of the nature of gas (nitrogen, argon and air) on the viscosity of crude oil at different temperatures and pressures was analyzed. It is shown that crude oil viscosities depend on gas composition. On the other hand, the influence of the composition of binary gas mixtures in a wide range of temperatures and pressures on the viscosity of heavy oil has been studied. The activation energies of flow are calculated for two types of gas mixture. It is shown that the gas phase at different ratios of the components does not significantly affect the rheological parameters of crude oil.

Deficiency of fossil minerals, limited reserves of conventional hydrocarbon raw materials indicates the need to involve in the fuel and energy complex of other sources of hydrocarbons. Fields of super-viscous oil are one of the sources. Development of super-viscous oil deposits opens new challenges in the field of building geological models associated with the shallow occurrence of these deposits. This article is devoted to the study of sediments of the Permian sedimentary complex containing super-viscous oil deposits. Study object is Sheshmian sandstone pack of the Ufimian stage. The pack is composed of sands and sandstones with different degree of carbonate cementation with small interlayers of siltstones. Cementation is the main factor which affect reservoir quality. In the process of analysis and preparation of the initial data and, subsequently, the geological model construction, the main features of the super-viscous oil deposits were revealed.

In order to regulate temperature of oil saturation with paraffins to avoid asphaltene, resin and paraffin substances (ARP-S) deposition using thermal method as well as chemical reagents and additives implementation was considered. A particular attention is paid to the chemical composition of the produced hydrocarbons, as well as to the effect of individual high-molecular components of hydrocarbons during the extraction and further transportation at low temperatures and with a temperature gradient difference. The paper presents the influence of hydrocarbon composition on the development mechanism, the composition and the properties of ARP-S. The methods for the removal of deposits associated with the use of various additives and reagents, as well as the methods for the prevention of these sediments development are considered. A brief description of the main classes of chemicals used for the solution of ARP-S prevention and removal problem is given. It was shown that in order to select the most effective ways of organic substance sediment prevention and removal from the physical-chemical point of view, it is necessary to obtain an idea about the composition and the properties of the initial oil and the developed deposits.

Natural accumulations of bitumen in the Volga-Ural oil and gas province are unconventional sources of hydrocarbons. They are mainly concentrated in the Republic of Tatarstan and are confined to psammitic (sandy) rocks of lower Permian age (Sheshmian Horizon of Ufimian Stage). Sands and sandstones belong to the greywacke group, so rock-forming minerals are represented by quartz, feldspars and effusive fragments. The internal structure of the bitumen-containing reservoir is characterized by an extreme degree of lithological and mineralogical heterogeneity, which is the result of the imposition of a whole complex of processes. Since the beginning of the development of bitumen deposits by thermal methods, the issues of studying the internal heterogeneity and its influence on the production process become particularly acute. Internal reservoir heterogeneity may prevent uniform heating and the formation of a full-fledged steam chamber. Sands and sandstones of the productive part are divided into three rock types (bituminous sands, bituminous sandstones and residual bituminous sandstones). Thermal studies using methods of thermogravimetry (TG) and differential scanning calorimetry (DSC) showed differences in rock types in terms of the decomposition of mineral and organic components, as well as the removal of gaseous components. As a result of thermal studies, it was found that not only loose, bitumen-saturated sands, but also denser, cemented rock types can serve as a reservoir for hydrocarbons. This is due to the conservation of hydrocarbon fractions in the intergranular space during the formation of carbonate cement.

Using of thermal methods of influence on the formation allows engaging in the extraction unconventional sources of hydrocarbons. One of the most important unconventional oil and gas objects are highly carbonaceous deposits. On the territory of the Volga-Ural oil and gas province, such objects is the Domanik Formation, which are clayey-siliceous-carbonate shale rocks with a high content of organic matter (OM). To identify and clarify the mechanisms of formation of oil and gas fields, as well as forecast and search for promising areas in the area of distribution of shale strata, the method of measuring the reflectivity of vitrinite is used. However, the absence of residues of plant organic matter in the Domanikites creates difficulties in applying the method. To assess the prospects of individual sections of the Domanik Formation, it is possible to use the paleotemperatures of the field of adjacent and overlying sediments, where coal seams and inclusions of plant organic matter are present. The basis of this approach is the paragenetic association of oil, coal and shale sediments. The formation of shale and coal-bearing formations is due to the primary conditions of sedimentation, and the formation of oil and gas deposits is associated with deep thermal effects during periods of tectonic activation on the territory. The structure of modern thermal fields, due to changes in temperature values, is controlled by the location of zones of deep faults in the crystalline basement of the platforms. Paleotemperatures are determined quite accurately by the degree of catagenetic transformation of organic matter (OM), which can be used to reconstruct the structure of ancient thermal fields in sedimentary formations and identify areas of maximum warming. Regional patterns of change in the degree of coal metamorphism can be used as a basis for forecasting and identifying promising areas of oil and gas shale raw materials.

This article presents the distribution of natural bitumen in the sediments of the Kazan tier of the middle Permian. Natural bitumens, concentrated in the Permian sediments of the Republic of Tatarstan, occur at shallow depths and are heavy, highly viscous, hypergenically converted oils. In the tectonic relation, the area of maximum Kazan bitumen occurrence is confined to the Melekess depression and the adjacent slope of the South Tatar arch.

The present paper shows the thermal features of the treatment on the reservoir, geochemistry of sediments, and intensity of chemical weathering of terrigenous rocks of the Ufimian-Kazanian natural reservoir of the section of Karkali in the basin of the r. Sheshma and r. Inesh, to predict the efficiency forecast of the application of heat-treat at the object and decipher the genesis of sedimentary formations in the area. Changes in the main elements in rocks are represented in the variation diagram.

The settings, scale and geometry of lab facilities to simulate enhanced recovery methods play a significant role in the approximation of underground conditions of oil fields. The reliability more or less of the best replication of these conditions is a question of the reservoir engineer when forecasts are made for cases when enhanced recovery methods are applied. This paper presents the results of two experiments carried on in a steam flooding tube facility adding clay in one of them to assess the influence in temperature growth and production rates and onset times of a highly viscous oil field of the Tatarstan Republic. The results of the runs show that 4% (by weight) of clay content in the porous media has a strong effect on the overall oil recovery, reducing the temperature growth rate in average 73% when steam stimulation methods are used.

The author in this paper determined the coefficient of porosity from well log data and carried on a study of core samples using X-ray microtomography and traditional methods. A method was elaborated and later tested for measurement of porosity of samples taken from the production interval of shallow super viscous oil deposits of the Tatarstan's Republic. Also determination of mineralogical composition and characteristics of the reservoir rock for application to future steam flooding experiments. On the basis of the data obtained, was concluded which of the methods gives the most reliable information on this of the reservoir rock under study.

In the research is built the mathematical model of the isoprene polymerization process in the presence of microheterogeneous neodimium catalytic systems. The direct problem is solved and is analyzed the molecular-mass distribution of the polymer. An algorithm of solving the inverse problem for search and elaboration of the kinetic parameters of the research process is developed.

A set of algorithms for determining the averaged molecular characteristics of the polymer and finding the optimal initial concentrations was built on the basis of the mathematical software for solving rigid and non-rigid systems of ordinary differential equations describing various polymerization processes. With the help of the developed mathematical and software computational experiments were carried out for various technological parameters and production recipes for the considered processes. The dependencies of the molecular mass characteristics of the copolymer on the time of polymerization or conversion of monomers were built, which showed agreement with the data obtained as a result of experiments in the central factory laboratory of Synthez-Kauchuk OJSC (Sterlitamak, Republic of Bashkortostan) and the laboratory of physico-chemical studies of polymers of BashSU.

With the development of unconventional resources the standard task of evaluation the porosity and oil saturation needs new approach. Heavy oil and bitumen can act as cement in many sand reservoirs, which excludes the use of standard measuring techniques. A new method for estimating the porosity and oil saturation of heavy oil reservoirs, based on wavelet X-ray computed tomography histogram analysis, was proposed. Its advantages are the ability to work with loose sand reservoirs, for which it is not possible to use standard assessment methods. A comparative analysis of the proposed method with a standard method for estimating porosity based on sample saturation with kerosene showed that the values of the porosity coefficient in the tomography resolution range 5-15 μm differed by 3-7% in the direction of the wavelet analysis method. This effect is due to the presence of transient voxels – mixels.

As the global supply of traditional oil shrinks, the energy industry invests heavily in the unconventional energy resources, such as oil shale. One of big potential resources of oil shale that locates on the territory of Volga-Ural Basin in the East of Russian plate is Domanik. Its increasing significance led to the necessity for deeper understanding of Domanik porous space structure. The main idea of this work is to establish the changing of pore structure during the heating. As result, increasing the porosity to 3 times as a result of heating of the oil shale was established. The distribution of heated to 350° C sample demonstrated decreasing the ratio of pores with sizes 1.5-5 µm and significant increasing the ratio of pores with sizes 5-10 µm. It means that main changing of pore structure during the heating happened with organic matter pores. The increasing of the volumes of pores with sizes 10-25 µm that could be connected with generation of elongated cracks along the shale lamination. The results opens new opportunities for evaluation of maturity of organic matter based on pore structure analysis.

Nowadays, cases of the joint use of thermal and chemical methods of enhanced oil recovery have become more frequent. In this regard, acid treatment has an important role, which allows increasing the productivity of wells with low-permeability carbonate reservoirs. At the experimental level, the presence of an optimal injection mode has been proven, that depends on the dimensionless of Damköhler number and leads to the formation of "wormholes" of dissolution with increasing reservoir permeability. In this work, a new optimized method for calculating the Damköhler number based on X-ray computed tomography data is proposed. A comparison of the calculation of values by the classical and the new technique for different wormholes is presented.

The study of the staging of the thermal conversion of oil shale, common in the Middle Volga region, was carried out. It is established that the organic matter of rocks due to the polycomponent composition undergoes multi-stage pyrolysis in the temperature range 200-600°C. The most favorable temperature of pyrolysis, when up to 80% of the potential heat of shale is released, falls within the interval of 460-480°C. The main thermal transformations of the ash component are carried out at temperatures above 480°C. They are due to the release from the structure of clay minerals of the OH group, the oxidation of pyrite, the decomposition of calcite and the formation of spinels.

Summing up the obtained results, we can draw to the following conclusions:

1. Oil shale of the Middle Volga region is characterized by significant variations in the content of organic matter from 9 to 40%. The light isotopes C12 predominance in the composition of organic carbon indicates the predominantly biochemical origin of the organic matter.

2. The configuration of the DSC curve in the temperature range of 200–600°C indicates both the multicomponent composition of the organic compounds of oil shale and their multi-stage pyrolysis.

3. The most favorable pyrolysis temperature, when up to 80% of the potential heat of shale is released, is in the range of 460-480°C.

4. In the process of burning oil shale, the ash component of the rock also subjected to thermal transformation. The composition of rock-forming minerals determined the main temperature ranges of transformation in the areas of 480–600°C (extraction of hydroxyl water from clays, oxidation of pyrite with the formation of hematite), 680–800°C (destruction of calcite), 880–900°C (formation of spinels).

Aquathermolysis process is one of the key technologies of reducing the viscosity and exploitation of huge deposits of heavy crude oil. That process combines thermal and catalytical effects in the presence of water. There are a lot of types of catalysts used in aquathermolysis process, such as water and oil soluble, heterogeneous catalysts and minerals. One of the type of heterogeneous catalysts are pillared clays that used in catalytic, sorption and separation processes. Pillared clays (PILC) are the class of two-dimensional micro-mesoporous materials that have a high specific surface area, constant porosity, developed texture and active compaunds in the structure, i.e. combine both the carrier and the catalyst. In this study the physico-chemical properties of Fe-pillared clays and its application in the "reconnaissance" heavy oil catalytic aquathermolysis experiments of has been investigated.

In order to increase hydrocarbon reserves in recent years, begun to actively involve natural bitumens in the development. On the territory of Tatarstan, one of the experimental sites for testing various technologies for the extraction of bitumen is the Lower-Karmalinsky bitumen deposit. Currently, on the field is testing the SAFD method. According to this technology for the extraction of hydrocarbons, steam is pumped in large volumes at a temperature of about + 180°C. Superheated steam reduces the viscosity of hydrocarbons, making them mobile. However, focusing on the reduction of bitumen viscosity, the problem of mineral phase's transformation due to anthropogenic impact in reservoir is not taken into account. In this work, using thermodynamic modeling, it was shown that the injection of superheated steam into the formation of bitumen-saturated sandstone will lead to the dissolution of calcite cement. Moreover, depending on the salinity of the injected water in the form of steam, the dissolution of carbonates will occur at different temperatures. To improve the technological characteristics and to increase the recoverability of bitumen from reservoir, it is recommended to pump hot water with as little mineralization as possible into sandstone layers. Temperature intervals were established, which should be followed in the process of technological development of bitumen collectors at the stage of heating the reservoir and at the stage of extracting water-bitumen solutions.

Authors of the article identified the influence of sedimentation conditions on reservoir thickness and the patterns of change in reservoir properties of superviscous oil field from the following three zones of the sandstone sequence of the Sheshminsky horizon: Northern, Southern and Central identified by PJSC Tatneft and prepared for initial development. The following relationships have been investigated: open porosity relation with bitumen content (by weight and by volume), open porosity relation with carbonate content, open porosity relation with bulk density, carbonate content relation with bulk density, bitumen content (by weight and by volume) relation with carbonate content, and also bitumen content relation with their depth. The revealed patterns of changes in reservoir properties and bitumen content within the sandstone sequence can be the result of not only changing conditions of sedimentation, but also the result of post-sedimentation processes resulting in calcitization or redistribution of carbonate cement in the rock under the influence of aggressive products (oxidation, biodegradation) of oil deposits destruction.

The area of the Volga-Ural oil and gas basin belongs to the "old" oil and gas bearing regions. The most part of easily recoverable reserves of large and unique oil fields already have been developed within the area. Therefore, super-viscous oil reservoirs, natural bitumen deposits and shale hydrocarbons seized the attention of local petroleum geologists. Tatarstan is a classic example in that sense. The Republic of Tatarstan is a leader in the development of heavy oil resources, a leader in the degree of knowledge of natural bitumen accumulations, as well as a leader in technological readiness for their development. In the depths of Tatarstan, there are more than 450 fields of ultra-viscous oil and natural bitumen with reserves ranging from 2 to 7 billion tons of this type of hydrocarbons. However, their industrial development due to low profitability is slow. To solve the problem, it is necessary to search for and commercialize economically viable technologies for the production, transportation and processing of hydrocarbons, which take into account its features and do not require increased energy and other material costs. Therefore, the search for the right unconventional hydrocarbons production concept is an urgent problem of our time.

In recent years, the expansion of the base of energy raw materials occurs through the involvement of new unconventional sources into operation. The development of new technologies made it possible to extract methane and its homologues from sedimentary formations that were not previously considered as sources of natural gas. One of these formations are coal-bearing strata. In some cases, the development of coal seams using traditional methods (quarry and mine) is impossible due to mining, geological, economic, technical and other reasons. The volume of industrial production of coalbed methane in foreign countries is beginning to have a significant impact on global gas markets. Industrial extraction of methane is conducted in the USA, China, Canada and other industrialized countries. It should be noted that the potential of unconventional resources of methane is huge - the resources of coal in the world reach 15 trillion tons. Coals are a promising source of coalbed methane. Gas output can be increased by thermal exposure to the coal seam. We have carried out studies of residual gas components from samples of fossil coal by the method of combined thermogravimetry (TG) and IR spectroscopy (IR). The method of thermogravimetry allows us to estimate the amount of gas sorbed in the coals, and IR spectroscopy to identify the composition of the emitted gases in each temperature range. Data on the composition of gas fractions in various temperature ranges was obtained.

Currently, the role of unconventional facilities for hydrocarbons is increasing. Such objects include the Domanik rocks (Republic of Tatarstan) and Bazhenov deposits (Western Siberia). The article presents the results of studying the type of organic matter of the Bazhenov suite and studying the process of pyrolysis of organic matter. It is established that the formation of new free hydrocarbon radicals occurs at temperatures up to 350°C (pyrolysis of organic matter). This indicates that the rocks of the Bazhenov suite did not fully realize their hydrocarbon potential. The deposits of the "normal" section of the Bazhenov suite not only contain a large amount of ready and hard to recover hydrocarbons, but also have an additional generation potential.

The article describes the results of implementation tracer studies at one of the super-viscous oil deposits in the Republic of Tatarstan. Accurate information on the flow of liquid in oil deposits is absent, this is an obstacle to the successful development of such deposits. The information obtained as a result of tracer studies is an addition to the general history of field development and is used to reduce uncertainties in the construction of geological and hydrodynamic models of deposits. The main tasks were the determination of the hydrodynamic connection between the wells along channels with low filtration resistance, the determination of the filtration rates of the condensate in the reservoir and the heterogeneity of the reservoir in the inter-well space of the investigated section of the oilfield. In order to determine the quality of the hydrodynamic connection within the bituminous deposit, the geological structure, as well as the direction of the filtration streams, a solution of the chemical eosin indicator was pumped into one of the steam injection wells, followed by registration in the samples of the surrounding production wells. To detect fluorescent indicators in the wells, unique equipment was used that significantly reduces the previous sample processing and detection time.

In this study, thermal conversion experiments of heavy oil using steam and formic acid as a hydrogen donor were carried out in a batch reactor at T = 380 °C and P = 165 bar. Material balance and products distribution were calculated after the experiments. Properties of crude oil before and after thermal conversion were analyzed including: viscosity, API gravity, SARA and elemental analysis measurements. It was shown, that application of formic acid as a hydrogen-donor solvent leads to the reduction of coke and gaseous products formation and to the increase of liquid products yield. In addition, the viscosity of upgraded oil was decreased by 23.2% due to addition of formic acid in comparison with thermal conversion without the hydrogen-donor solvent.

The purpose of this work is to test the upgrading technology by supercritical water of two different raw materials heavy oil and vacuum distillation residue. The experiments were carried out under the same conditions (temperature 400 °C, pressure 236 bar). The products obtained after upgrading were analyzed. Density, viscosity, SARA-composition, elemental composition and composition of saturates fraction were determined. The results revealed that after upgrading at 400 °C during 60 minutes raw materials heavy oil and vacuum residues yielded light oil 85.6 % and 64.7 %, coke at level of 11.3 % and 13.7 % and gaseous products 3.1 % and 21.6 %.