Kazakhstan journal for oil & gas industry

The article analyzes the features of the formation of the Precaspian salt basin and salt dome tectonics in the southeast of the depression. It presents a model of a salt accumulation basin that is linked to its isolation from the Paleotethys Ocean and a unidirectional water inflow. These factors resulted in the deposition of evaporites including thick layers of rock salt under conditions of intense aridification. The halotectonic mechanisms responsible for the formation of salt domes and diapirs were found to be active, passive, and reactive. The first and last cases were identified through the involvement of fault tectonics in the development; the mechanism of passive halotectonics is associated with a prograding wedge, or gradual lateral buildup, of the strata and the rise in the load of overlying rocks. Salt domes are considered to be related to the filling of the basin with terrigenous clastics and the movement of salt layers from the sides to the center. Later, salt diapirs were manifested due to tectonic stress during the formation of the northern margin of the Paleo- and Neotethys, its closure and the collision of small Iranian continental blocks, island arcs and accretionary prisms originating from the south of the Caspian basin.

Background: As demand for hydrocarbons continues to grow, oil and gas industry operators are faced with drilling deeper wells to access previously unattainable hydrocarbons. The importance of deep and ultra-deep well exploration is rapidly increasing to meet the growing global demand for oil and gas. Drilling at such depths poses a wide range of challenges. Most accidents and complications are caused by the use of drilling fluid that does not meet the drilling conditions. The need to develop deep pays requires the use of drilling fluids that can prevent dispersion and hydration of clayey rocks and ensure long-term wellbore stability and high-quality penetration of productive formations.

Aim: The purpose of the analysis on this subject is to consider the dependence of the properties of drilling fluid based on acrylamide polymer additives and to analyse the influence of polyacrylamide concentrations on the technological parameters of drilling fluids.

Materials and methods: This study considers a synthetic high-molecular compound used for treatment drilling fluids – polyacrylamide and gaseous drilling agents. Polyacrylamide works as a filtration reducer only in clayey drilling fluids and is ineffective in this capacity in solutions without a solid phase. However, as an aqueous phase thickener, it can be successfully used in clay-free systems, including mineralized aqueous solutions.

Results: Justification of the parameters and quality of the flushing liquid and the use of solutions used at the Zholamanov field and practically tested by PETRO-UNIT LLP.

Conclusion: The use of aerated fluids provides a number of benefits: minor deterioration of reservoir properties, rapid evaluation of cuttings for hydrocarbons, loss of circulation prevention, and significantly higher penetration rates in hard rock formations. Additional costs associated with the necessary equipment are taken into account, both for drilling with conventional drilling fluids and for drilling with gaseous agents. It is necessary to have properly functioning purificationsystem equipment at the drilling rig in order to ensure effective purification of the drilling fluid from the solid phase, which will reduce the cost of processing the solution, since with an increase in the solid phase content, the density of the solution, rheological properties and clay colloidal phase increase.

Background: In developing mature fields, the issue of technology efficacy is often raised in the context of constrained reservoirs, such as reservoirs with small interstices (barriers) bordering water- or gas-saturated reservoirs. The ability to effectively developing such reservoirs increases the production of current reserves and prolongs the "life" of the fields under development. This study presents the experience of Gazprom Neft Group in the development of terrigenous reservoirs, where there is a high risk of a fracture penetration into water- and gas-saturated intervals, by hydraulic fracturing. This experience can be taken as a basis for increasing the production of current reserves for some mature fields under similar geological conditions, where this problem is particularly acute and requires solutions that minimize risks.

Aim: Selecting the optimal technological approach to ensure the technical and economic viability of projects involving late-stage fields or assetswith with under- or overlying watered reservoirs.

Materials and methods: The materials address several technological trends, consisting of the completion specifics and the technological approach to hydraulic fracturing. As the main solution, a combination of low-viscosity fluids with a polymer concentration ranging from 2.8 to 3.2 kg/m³ in various executitions, 20/40 and 16/20 proppant fractions, as well as completion with a cemented equal-hole diameter tailpipe with burst port collar. The presented vision allows not only to significantly reduce the risks to fracture penetration in lower (upper) layers, but also allows, in cases of Screen Out, to perform clean out jobs without involving expensive Coil Tubing operations.

Findings: The implemented integrated solutions have proven their effectiveness at facilities with restrictions on fracture propagation in height. The use of low-viscosity liquids made it possible to reduce the increase in water saturation of products after stimulation, and design solutions reduced the costs associated with such as Screen Out.

Conclusion: The experience gained in applying new technological solutions to wells with a high risk of a fracture penetration into water- and gas-saturated intervals is quite successful, which confirmed by actual work and well analysis. Hydraulic fracturing on linear gel has a highly potential in the fields of Gazprom Neft Group and can be using on the similar formations.

Background: Nowadays industry best practices demonstrate that routine evaluation of pipeline risk enables more efficient resource allocation, particularly by focusing efforts on critical areas. Consequently, process of analyzing the risks associated with operating different facilities in petroleum industry should be considered a fundamental prerequisite for decision-making, especially while managing pipeline network’s integrity. In the Republic of Kazakhstan, the current decision-making framework is founded upon the "technical condition" management model, which differs significantly from the risk-based approach prevalent in the international oil and gas industry. Moreover, as a result of the absence of the comprehensive failure statistics in the petroleum industry of the Republic of Kazakhstan, it makes it even more complicated to implement proper quantitative risk assessment.

Aim: This article aims to demonstrate how customized risk model can be developed to reflect specific conditions and challenges related with the working environment, dangers and threats, as well as data’s quality and availability in Kazakhstan.

Materials and methods: QPRAM (quantitative pipeline risk assessment model), industrial data for the given pipeline X.

Results: The model illustrates fundamental and most important risk factors at high-resolution intervals along the pipeline’s network and was calibrated using real data from the industry to ensure that the resulting risk profiles are reflective of the possible threats and existing operating experience in the given region.

Conclusion: Through the adoption of QPRAM's guiding concepts and methods, all parties in industry may strengthen operational resilience and safety standards against potential threats, protecting the long-term stability and dependability of critical infrastructure networks.

Background: Due to the exhaustibility of active reserves of light oil, every year it becomes more and more important to improve the developmental efficiency of heavy high-viscosity oil fields. There is a need for a deeper study of the properties of high-viscosity oil in order to improve enhanced oil recovery technologies.

Aim: The investigation of West Kazakhstan’s high-viscosity oils’ rheological properties by studying their physical and chemical characteristics and content of high-molecular compounds.

Materials and methods: As objects of the study, oils from Western Kazakhstan's Karazhanbas, Northern Buzachi and Zhalgyztobe oil fields were selected. To accomplish the given tasks, laboratory studies were conducted using contemporary methods of chemical and physicochemical analysis.

Results: This article presents the results of laboratory studies to determine the density, viscosity, and content of asphalt-resin-paraffin substances with a comparison of the results obtained. As well as the results of the study of the rheological characteristics of heavy high-viscosity oil with different water cut on the example of fields in Western Kazakhstan. The temperature limits and the influence of water cut on the manifestation of non-Newtonian properties were determined.

Conclusion: It was found that the rheological behavior of high-viscosity heavy oil with different water cut exhibits pronounced properties of pseudoplastic liquid, where the most pronounced non-Newtonian properties are manifested at the content of bound water exceeding 50%. The expression of non-Newtonian properties of West Kazakhstan oil is due to the increased content of high-molecular components. The obtained results are of practical interest in creating a composite model of hydrodynamic and technological system of collection and transportation of heavy, high-viscosity oil.

Background: The world’s population is currently experiencing a daily decline in mineral resources, aggravating environmental problems and energy deficit, and economic and social instability . The rising number of consumers and the wasteful use of natural resources are two factors contributing to these processes. One strategy to prevent these issues is to find alternative and renewable energy sources and efficiently use resources—the so-called "green economy" transition.

Aim: The aim is to identify the prerequisites for the nation to become one of the developed nations of the world by 2050 by implementing the "green economy" concept and guaranteeing the systematic development of economic, social, and political values of Kazakhstan.

Materials and methods: The research was conducted using generalisation and analysing data from countries implementing the "green economy" programme. The application of general scientific research methods within the framework of a comparative, logical, and static analysis of the Republic of Kazakhstan's "green economy" concept served as the foundation for solving the assigned tasks.

Results: According to the study, the application of the "green economy" concept—which aims to improve living conditions for the populace through the utilising technologies based on the economical consumption of natural resources and the efficient and rational use of renewable energy resources—is unquestionably necessary in order to meet the basic prerequisites.

Conclusion: The introduction of renewable energy sources will improve the energy efficiency of the economy and enable it to move to low-carbon technologies. The transition to a green economy will allow Kazakhstan to avoid the environmental crisis that has already affected many countries.

Background: This study is aimed at reducing liquid waste in the process of reverse osmotic demineralization of water using an electromagnetic treatment. A side effect of this is the deposition of salts on the reverse osmotic membranes used, which reduces their service life. This leads to a decrease in the performance of the equipment, and, respectively, the membranes used are subjected to further flushing or replacement. The article presents data on long-term tests conducted by Pavlodar Petrochemical Plant LLP on the effectiveness of electromagnetic treatment technology in the process of reverse osmotic purification of water vapor condensate to ensure a minimum volume of concentrate (brine) of no more than 10% and to prevent intensive salt deposition on reverse osmotic membranes.

Aim: Investigate the possibility of using an electromagnetic treatment device to extend the service life of reverse osmotic membranes during steam condensate purification of Pavlodar Petrochemical Plant LLP.

Materials and methods: For this study, "Termite" electronic hardness salt converter was used, which treats water with electromagnetic waves and not only prevents the formation of scale, but also removes the scale already present in the equipment.

Findings: After being treated with an electromagnetic treatment device in the reverse osmosis process, samples of treated water showed a decrease in total salt content to 1.26 mg/kg and iron content from 84 to 10 µg/dm³. At the same time, the water's pH virtually stayed the same. The specific electrical conductivity of steam condensate was found to be 5.0 microns/cm, which corresponds to a value that does not exceed the required standards.

Conclusion: Tests on steam condensate purification carried out by the Pavlodar Petrochemical Plant using pulsed electromagnetic treatment in the reverse osmosis process showed a positive result in reducing the total salt content, in particular iron, as well as water hardness.