Gazovaya promyshlennost’ Спецвыпуск № 2 2019

It is hard to overestimate the role of flow meters in modern industrial society; it has significantly increased recently due to the need for saving and rational use of continuously appreciating energy and water resources throughout the world. Flow meters enable automated process control and optimization of operating conditions in almost every industry. Contemporary requirements for flow meters include high precision of measurement, reliability, fast response, large measurement range (Qmax/Qmin), ability to measure under extreme conditions (within temperature range from –220 to 600 °C), readings stability, low power consumption, etc. These requirements are completely met by ultrasonic method, which has become widespread over the last years, due to the immanent physical measurement principle and specific features that allow to use ultrasound for non-contact measurements in corrosive and explosive environments. Another important advantage of ultrasonic flow meters over the other types is that they make it possible to obtain some additional information on the physical and chemical parameters of measurement medium and flow, through indirect calculations. The paper provides an example of practical implementation of built-in self-diagnostics system for UFG ultrasonic flow meter. This system is fully compliant with the requirements of GOST 8.611–2013, which includes monitoring the signal amplification level, signal quality, signal-to-noise ratio, monitoring the ratio between the gas velocity through acoustic channels to average gas velocity in flow transducer, as well as sound velocity. The diagnostic system has been repeatedly tested in actual operating conditions and has also other benefits, such as control of electronic unit status and flow properties (profile, symmetry, turbulence evaluation), informativeness, records archiving, and an intuitive user-friendly interface. Some perspective directions for the further development of ultrasonic flow meters are described. They include density and viscosity calculations and acoustic estimation of measurement medium composition, in order to obtain information on the energy value of energy carriers.

Today it is necessary to bring the information and measurement systems into compliance with the requirements of ANSI/NACE MR0175/ISO 15156 Petroleum and natural gas industries – Materials for use in H2S-containing environments in oil and gas production for the purpose of technical re-equipment and reconstruction of Astrakchan and Orenburg oil fields facilities. These fields' formation fluid contains hydrogen sulphide as well as mercaptan sulfur. The environmental parameters set by the general designer, YuzhNIIgiprogaz, should be considered. Thus, there is a need for the development of Gazprom’s regulatory documents stipulating the requirements for measuring instruments and information and measurement systems applied at Astrakhan and Orenburg gas condensate fields as part of the import substitution program. This will help local producers assess the compliance of their equipment with these requirements and ensure safe operation of production facilities.

The telemechanical systems are the most important systems for automation of pipeline gas transmission process. Linear telemechanical systems provide to the staff the on-line control over process parameters of linear gas pipeline facilities distributed at significant distances and timely management of the facilities in standard and emergency situations. Therefore, ensuring the reliability of process data is especially relevant. The paper covers individual aspects of the metrological support of linear telemechanical systems and leak detection systems – main types of metering channel errors, reasons of occurrence and ways to reduce them.

The article summarizes the experience of implementation and maintenance of laboratory information systems aimed to improve the efficiency of Gazprom PJSC subsidiaries» chemical analysis laboratories in accordance with STO Gazprom 5.50‑2014. Specialized software such as laboratory information systems is needed because of the laboratory staff's responsibilities to perform routine operations, generate reports, and conduct procedures aimed to maintain a high level of laboratory competence. Over the years, laboratory information systems has allowed laboratories to resolve such tasks as obtaining, using and storing experimental data. The article considers functional tasks formalized in STO Gazprom 5.50‑2014 and peculiarities of their execution through implementation of laboratory information systems in subsidiary companies. These tasks include ensuring the following: examination of laboratories» competence and validation of delivered results (which includes self-audit and interlaboratory comparison tests); automatic transfer of measurement results and reducing the likelihood of errors that arise when the data is transferred manually; rapid data transfer to central laboratory from geographically remote ones; data transfer to the Federal Service for Accreditation. The time spent on internal laboratory control calculations using laboratory information systems has been estimated in comparison with other calculating options. Software functions available for laboratory after the successful implementation are also specified in the article. It is concluded that LIS can be a reliable software tool for automation of laboratory work, along with meeting the requirements of regulations and controlling entities.

The growth of production rates and the rise in energy price necessitates the need for metering devices, while placing high demands on their reliability, accuracy and measurement results reproducibility. Among a wide variety of measuring gas flow methods and facilities, ultrasonic flow meters occupy a leading position due to their characteristic features and high accuracy. In view of the global trend towards the energy efficient use, the ultrasonic method is being increasingly used in gas composition indirect measurements for identifying its energy value due to its ability to determine the sound speed in the environment. This paper outlines the principle of gas flow ultrasonic measurement, describes the main destabilizing factors that have a direct impact on the measurement results, discusses methods for improving the metrological reliability of metering devices. The paper assesses metrological properties of the flowmeters, the satisfactory values of which confirm the efficiency of methods used to reduce the destabilizing effects.

The article gives an overview of gas supply by Gazprom Mezhregiongaz LLC Group of Companies in Russian Federation and addresses challenges of measurement uniformity assurance for gas consumption (volume) and process parameters during gas transfer to distribution grids and consumer distribution. The article also describes core activities to improve the state of measurement and gas metering system in general by developing legal and methodological frameworks, applying advanced measuring equipment and control tools, and enhancing the skill level of staff.

With increasing quality requirements for gas exported to European Union and introduction of the new regulations on oxygen content in natural gas, development and implement of advanced methods for trace oxygen determination is becoming an immediate task. The article proposes to consider spectral luminescent method of analysis for determination of trace oxygen in natural gas. This method has a number of advantages over methods currently used by various manufacturers of flow oxygen analyzers, including chemical, chromatographic and electrochemical ones. Detection is based on luminescence quenching as luminophore’s triplet state annihilates effectively with ground state singlet oxygen. According to this, molecular oxygen content is determined on the basis of luminescence intensity. A large quantum yield of luminescence, high sensitivity of modern equipment, as well as wavelength options, enable the automated solutions for determination of less than 1 ppm oxygen. Oxygen content measurement in gas medium is based on luminescence quenching intensity of a polyatomic organic compound (luminophore) on a solid support, which is an adsorbing material with large BET surface area, in gas medium varying with oxygen content in that medium. Compositions and films, for instance, based on flavonoids, polynuclear aromatics, polymers or coloring agents, can be used as luminophores. Actual values obtained for intrinsic absolute errors are 3–6 times lower than reference values for 1.0–200 ppm range and at least an order of magnitude lower for 50–10,000 ppm range. Construction of Oksi-OMA flow analyzer prototype for trace oxygen in natural gas is provided. The instrument has 2 modifications: for molar fraction measurement range of 1.00–200 ppm with an accuracy of ±(0.15+0.05·Свх) and for 50-10,000 ppm range with an accuracy of ±(7.5+0.03·Свх). The analyzer’s explosion-proof marking is as follows: 1Ex d op pr [ia Ga] IIВ+Н2 T4 Gb X. Analyser ensures generation of current analog output signal of (4–20 mA) and (or) via RS 485 serial interface card, or Ethernet digital signal.

This paper highlights the current problems of analyzing the composition of natural gas of variable composition. The authors consider in depth the composition of natural gas, methods of its production and the peculiarities of measuring the content of gas components, the composition of which varies in the period between consecutive measurements. The results of testing MAG process gas chromatograph "MAG" according to STO Gazprom 5.67–2016 Methodology for Measuring the Molar Fraction of Components and Determining the Physical-Chemical Parameters of Natural Gas for Measuring Units with Variable Gas Composition are observed. The main attention is paid to checking the linearity of the detectors that make up the chromatograph, checking the acceptability of the calibration characteristics and assessing the variance of the measurement results according to STO Gazprom 5.67–2016 and GOST 31371.7–2008.

The article considers organization of metrological support measuring operations during geophysical works at oil and gas wells. Specific features of measurement process and a measuring object are noted, which require consideration when setting up an effective metrological service at geophysical company and arranging technological processes during measuring operations. A metrological service structure with full equipment is shown exampled with the main contractor of Gazprom PJSC in the field of geophysical service, OOO Gazprom Georesurs. The article highlights the contribution of reference base for geophysical parameters to measurement uniformity assurance during geophysical well surveys at Gazprom PJSC facilities. It also lists contemporary basic reference and working standards that have proved successful in calibration of measuring equipment used at production site. Metrological support for geotechnical well testing during drilling operations is presented as an important dimension in geophysical service.

The article considers the main issues related to functioning of testing laboratories at Gazprom PJSC subsidiaries and companies. It is stressed that testing laboratories are vital in quality compliance of commercial output. Testing laboratories play an important role in determining the environmental parameters of production, as well as in receiving inspection of materials used, and in control of process parameters. In order to identify the laboratories’ qualification and their ability to meet production objectives at the required level, procedures are carried out to confirm the competence of laboratories in various accreditation systems. As a result of introduction of Technical Regulation of Eurasian Economic Union 046/2018, the procedure for compliance confirmation for all types of natural gas is to be changed. Furthermore, due to development of a significant number of new methods for determination of physical and chemical properties and component composition of natural gas, testing laboratories at Gazprom PJSC subsidiaries have to implement a set of measures to introduce new methods as well as to change the relevant guidance documents.

The paper presents the main types of flow meters used to measure natural gas flow rate and volume in Gazprom’s Unified Gas Supply System. The paper outlines the need to develop a unified European cubic meter for the Russian Federation and Europe. It shows the importance of examination, calibration and tests for modern natural gas flow meters under the wide range of flow rates and pressures. The paper studies the content, main functions and operation modes of the three lines of Gazprom’s Ural regional metrological centre. The conclusion points to the relevance of the Ural regional metrological centre development as an industrial research and production centre designed for examination, calibration and testing of modern natural gas flow meters and as a centre with a reference natural gas cubic meter, which allows to join the European gas flow metering control system.

The growing expansion of gas networks leads to an increase of natural gas transfer points. As a result, demand grows for reliable and stable reference values for measurement of high-pressure natural gas consumption. As there is no state primary special standard for the units of high-pressure natural gas flow rate in the Russian Federation, the gas meters at key points of supplied natural gas volume determination use the same measurement units as standards rooms of natural gas importing countries, which makes the Russian natural gas export system dependent. Currently, Federal State Unitary Enterprise «All-Russian Research Institute of Flow Metering» together with Gazprom PJSC is developing proposals on a project dedicated to development of a state primary special standard for the units of high-pressure natural gas flow rate, based on the advanced infrastructure of the Ural Regional Metrology Center OOO «Gazprom transgaz Yekaterinburg». These proposals include an action plan for project implementation and also concern organizational steps to recognize the entity as a national laboratory within the public-private partnership framework envisaged by the recommendations of CIPM 2005‑09. The main planned activities are: development of the reference standard; modernization of the Ural Regional Metrology Center to interface the reference standard with the existing measuring system, equipping the entity with facilities needed to transfer flow rate units step-by-step from the reference standard to working standards and measuring instruments via transfer standards. An analogue of the well-proven HPPP reference piston provers, which are primary standards for natural gas flow rate units in Germany and China, can be used as a reference standard. If HPPP are used as a reference standard, the procedure for transferring the gas flow rate unit to working measurement equipment can also be performed in line with the scheme implemented in Germany. Yet, the expanded uncertainty of working measuring equipment calibration in the range of natural gas flow rate 20‑70,000 m3/h at pressure up to 7.5 MPa shall not exceed 0.23 %, which corresponds to world»s leading standards rooms» characteristics for reproducing the units of high-pressure natural gas flow rate. Developing a state primary special standard for the units of high-pressure natural gas flow rate in the Russian Federation will make it possible to resolve a number of issues related to domestic gas consumption market as well as gas export market. It will also enhance the country»s energy security and strengthen the position of domestic fuel and energy complex in the international metrological community, in terms of measurement uniformity assurance for natural gas flow rate.

The article deals with the issues related to operation of standards rooms of subsidiaries and organizations of PJSC Gazprom. These standards rooms are aimed at ensuring uniformity of measurements. They are vital in preventing fallout from inaccurate measurement results. Laboratory staff confirms the serviceability of measuring equipment at industrial facilities by verification and calibration. In order to determine laboratories» qualification and their ability to perform production tasks at the required level, procedures are carried out to confirm their competence in various accreditation systems. There is a continuous process towards improvement of the corporate calibration system; the standard base is being strengthened, and documentary standards are being developed and updated.

Тhe article provides an overview of the developed by D.I. Mendeleyev Institute for Metrology methods and means of metrological support of measurements and new regulatory and technical documentation intended for carrying out quality control over hydrocarbon feedstock and its processing products using hardware-software chromatographic complexes based on laboratory and stream chromatographs. The paper covers the current state of the metrological support of measurements performed in the process of determining the component composition and physical and chemical properties of natural gas, liquefied hydrocarbon gases, unstable gas condensate and liquefied natural gas for the purposes of their commercial accounting.

The paper covers main issues related to various aspects of the activity of Technical Committee (TC) 052 on standardization. It provides detailed information on the main areas of activity of TC 052 subcommittees, outlines current and future objectives of the technical committee conditioned by the introduction of a new technical regulation ТР ЕАЭС 046/2018 On Combustible Natural Gas Prepared for Transportation and (or) Use and lists Gazprom’s product quality standards developed or planned for development under the auspices of TC 052. The paper describes the process of drawing up and prospects of developing the current set of standards on natural and liquified gases and provides the information on the activity of Intergovernmental Technical Committee on Standardization Natural and Liquified Gases. The paper covers the interaction of TC 052 with dedicated committees of the International Standardization Organization (ISO) and reveals the role of experts of the technical committee in the development of new international standards.

The article discusses the combined approach to solving the problem of unbalance of gas in the pipeline gas transportation system using formal and informal methods for constructing a mathematical model of an object (analytical and statistical methods) and algorithms for identifying its possible sources and causes. When calculating the gas balance in the transportation system, both directly measured and calculated parameters are used. The measurement error and the calculated definition of non-measurable parameters significantly affect the formation of balance. Theoretical solution and practical implementation of algorithms for quick identifying and eliminating the causes of a possible unbalance of gas will provide a qualitatively new level of control over the transportation system.

The article considers the main directions of business processes metrological support at Gazprom Energo LLC. Special attention is given to development, operation and updating of the multilevel automated system for commercial accounting of energy resources, as well as to metrological supervision, standard-setting activities aimed to regulate the metrological support and provide a detailed description of measuring equipment's life cycle phases. Metrological support attends all the stages of business processes at Gazprom Energo LLC, its subsidiaries and Gazprom PJSC companies, and is being implemented within existing integrated management system. This allows to focus the efforts effectively on primary goals. High level of metrological support is the keystone of providing high-quality service and production safety. This field of activity is regulated by legislation of the Russian Federation and local regulations of Gazprom PJSC and Gazprom Energo LLC. Due to increasing number of operated power assets and importance of timely and proper fulfillment of metrological support tasks, automation and establishment of data exchange are under way between the employees’ working places at company’s metrology service. Development of the company’s own standards room is in progress, as well as improvement in maintenance and repair. The standards room will be accredited to verify measuring instruments. Much attention is paid to professional growth of metrology service staff, their advanced training and skill-building. The joint development of technical and legal basis, as well as human resources, entitles Gazprom Energo LLC metrology service to play an important role in implementation business processes at the company.