Обоснование выбора винтовых насосных установок как энергоэффективной технологии механизированной добычи

The paper analyzes the main techniques and technologies of oil fluid recovery in the context of energy consumption, significantly rising over the latest decade. It is recognized that the number of publications in the area of energy efficiency is growing steadily. Currently Russian oil and gas industry are facing the task of accelerating reduction of energy consumption while preserving, or even increasing, production rates. The task is complicated by the fact that the majority of deposits in Russia either have already entered (primarily, Volga-Ural region) or are now entering (West Siberia) their last stage of exploration, whereas new deposits in East Siberia are only being brought into production. Furthermore, a lot of new deposits, which provide for high recovery rates, are profitable a priori as at the first stage of exploration they do not need any artificial lift due to their free flow production without any oil well pumps. However, there is a significant share of new deposits with low-permeability reservoirs, which require either a system of reservoir pressure maintenance or periodic hydraulic fracturing. At the same time deposits at the late stages of exploration, apart from the use of pump units, systems of reservoir pressure maintenance and hydraulic fracturing, require regular repair and restoration, measures against salt and heavy oil sediments, mechanical impurities, flooding, etc., which all has a negative effect on well profitability. In order to solve these problems, the authors review existing methods and calculate specific energy consumption using various pump systems for hypothetical wells, varying in yield. According to the research results, it has been revealed that from the point of view of energy efficiency, it is desirable to equip low- and low-yield wells with sucker rod progressive cavity pump units, medium-yield ones – with electric progressive cavity pumps driven by permanent magnet motor, medium- and high-yield wells – with electric progressive cavity pumps or electric submersible pumps driven by permanent magnet motor, depending on the characteristics of the pumpedout oil fluid.В статье проанализированы основные техники и технологии добычи нефтяного флюида в условиях значительного роста цен на электроэнергию за последнее десятилетие. Отмечен стабильный рост публикаций по теме энергоэффективности. Для российской нефтегазодобывающей промышленности актуальна задача снижения энегозатрат при  сохранении или даже увеличении темпов производства. Она осложняется тем, что большинство месторождений либо уже вступило (Волго-Уральский регион), либо вступает (Западная Сибирь) в последнюю стадию разработки, тогда как новые месторождения Восточной Сибири еще только вводятся в эксплуатацию. Кроме того, многие новые месторождения, обеспечивающие высокий дебет, рентабельны априори, на первом этапе эксплуатации не требуют механизации, поскольку разрабатываются фонтанным способом, без использования скважинных насосных установок. Но при этом немало и новых месторождений с низкопроницаемыми коллекторами, на которые необходимо воздействовать системой поддержания пластового давления либо проведением периодически гидравлического разрыва пласта. На месторождениях поздней стадии разработки необходимо регулярно осуществлять ремонтно-восстановительные работы, вести борьбу с отложениями солей, асфальтосмолопарафинов, механическими примесями, обводнением и пр., что негативно сказывается на рентабельности скважин. Для решения этих задач в статье рассмотрены существующие методики и проведены расчеты удельных энергозатрат при использовании различных насосных установок для условных скважин, отличающихся дебитом. По результатам исследований выявлено, что с точки зрения энергоэффективности низко- и малодебитные скважины желательно оснащать штанговыми винтовыми насосными установками, среднедебитные – электровинтовыми с вентильными двигателями, средне- и высокодебитные – электровинтовыми или электроцентробежными в зависимости от характеристик выкачиваемого нефтяного флюида

Анализ эффективности применения двух рабочих жидкостей с различными вязкоупругими характеристиками при гидродинамическом воздействии на призабойную зону пласта

Combination of hydrodynamic impact on the formation with acid treatment may be seen as a promising direction in the field of well development and repair in complex geological conditions. With multiple repetition of hydraulic shocks in conjunction with the injection of acid solution, the depth and opening of cracks gradually increases, which contributes to a deeper penetration of the acid solution into the reservoir. The article presents analytical studies, which are aimed at determining the effectiveness of applying the technology of hydrodynamic impact on the bottomhole zone of an oil reservoir when using two fluids with different viscoelastic characteristics as a working fluid. They are devoted to determining the pressure drop at the borehole bottom depending on the initial applied pressure at the wellhead, the velocity of the shock wave, the viscosity of the working and well fluid, and their quantity. These studies were based on the well-known models of Thomson – Tаt and Maxwell, considering viscous liquid flow. The dependence obtained proves that with an increase in the pressure pulse generated at the wellhead, the development of pressure pulses at the borehole bottom is a power-law dependence, and with significant volumes of fluid in contact with the bottomhole formation zone, the pressure drop generated at the borehole bottom does not depend only on pressure pulses generated at the wellhead, but also on the dynamic viscosity of this fluid. Conducted studies have shown the effectiveness of hydrodynamic impact technology application when using two liquids with different viscoelastic characteristics and obtaining a synergistic effect during the development and repair of wells in low-permeable reservoirs. Analytical studies were based on data from previously conducted experimental industrial tests on the operating injection well.Перспективным направлением разработки технологии освоения и ремонта скважин в сложных геологических условиях является совмещение гидродинамического воздействия на пласт с кислотной обработкой. При многократном повторении гидроударов в совокупности с закачкой кислотного раствора постепенно увеличиваются глубина и раскрытость трещин, что способствует более глубокому проникновению кислотного раствора в пласт. В статье проводятся аналитические исследования, направленные на установление эффективности применения технологии гидродинамического воздействия на призабойную зону нефтяного пласта при использовании в качестве рабочей жидкости двух жидкостей с различными вязкоупругими характеристиками. Определен перепад давления на забое скважины, зависящий от начального прикладываемого давления на устье, скорости ударной волны, вязкости рабочей и скважинной жидкостей и их количества. Исследования базировались на известных моделях течения вязкой жидкости Томсона – Тэта и Максвелла. Полученная зависимость доказывает, что при увеличении импульса давления, сгенерированного на устье скважины, развитие импульсов давления на забое происходит по степенной зависимости при значительных объемах жидкости, контактирующей с призабойной зоной пласта; перепад давления, создаваемый на забое скважины, зависит не только от импульсов давления, генерируемых на устье скважины, но и от динамической вязкости этой жидкости. Проведенные исследования доказывают эффективность применения технологии гидродинамического воздействия при использовании двух жидкостей с различными вязкоупругими характеристиками и получение синергетического эффекта при освоении и ремонте скважин в низкопроницаемых коллекторах. Аналитические исследования базировались на данных ранее проведенного опытно-промышленного испытания на действующей нагнетательной скважине

Электроснабжение станции нагрева нефти в скважине от ветроэлектрической установки

In this article, the authors reviewed a new technology to prevent the formation of asphalt-resin-paraffin deposits by the thermal method of electrothermal impact on the oil wellbore shaft using a wind-electric installation as an autonomous power source. The advantage of this thermal stimulation technique lies in its continuous nature, which will allow keeping the clear opening of the tubing constant. The scheme of the autonomous system for down-hole electric heating of oil is presented. A tubular or induction heater can serve as an electric heating element placed in the well. The heating element of the system can be used in the wells exploited by freeflow, gas lift and mechanized methods, while its installation does not require an overhaul. The paraffin oil saturation temperature and temperature distribution over the depth of the well were defined. The amount of heat, which must be transferred to the oil mixture in the tubing in order to ensure effective operation of the well, taking into account the dynamic state of the system, is calculated. The optimal depth of the heating element's location in the well and its power was determined. The calculation of the required power for wind-electric installation to maintain the set temperature in the wellbore was performed. Having conducted the studies, it was revealed that in order to prevent the asphalt-resin-paraffin deposits formation on the tubing walls of oil wells, it is expedient to use the in-line heater, which maintains the average steady-state temperature along the wellbore and at the wellhead above the initial crystallization point of the asphaltresin-paraffin deposits. The application of the developed electrothermal system is relevant in the conditions of formation of asphalt-resin-paraffin deposits in the wellbore shaft at the fields, which do not have a connection to the centralized power grid.Рассмотрена новая технология предупреждения образования асфальтосмолопарафиновых отложений тепловым методом электротермического воздействия на ствол нефтяной скважины с применением ветроэлектрической установки в качестве автономного источника питания. Достоинством данного теплового способа воздействия является его непрерывный характер, что позволяет сохранять пропускное сечение насосно-компрессорных труб постоянным. Представлена схема автономного комплекса для внутрискважинного электропрогрева нефти. В качестве электронагревательного элемента, размещаемого в скважине, может выступать трубчатый или индукционный нагреватель. Нагревательный элемент комплекса может применяться в скважинах, эксплуатируемых фонтанным, газлифтным и механизированным способами, при этом для его установки не требуется проведения капитального ремонта. Определены температура насыщения нефти парафином и ее распределение по глубине скважины. Рассчитано количество теплоты, которое необходимо сообщить скважинной продукции в насосно-компрессорных трубах для обеспечения эффективного режима эксплуатации скважины с учетом динамического состояния системы. Установлены оптимальная глубина расположения нагревательного элемента в скважине и его мощность. Выполнен расчет необходимой мощности ветроэлектрической установки для поддержания заданной температуры в стволе скважины. Проведенные исследования показали, что для предотвращения образования асфальтосмолопарафиновых отложений на стенках насосно-компрессорных труб нефтяных скважин целесообразно использовать проточный электронагреватель, который обеспечивает поддержание средней установившейся температуры по стволу и на устье скважины выше точки начальной кристаллизации асфальтосмолопарафиновых отложений. Применение разработанного электротермического комплекса является актуальным в условиях образования асфальтосмолопарафиновых отложений в стволе скважины на месторождениях, не имеющих подключения к централизованной энергосистеме установки для поддержания заданной температуры в стволе скважины

Анализ эффективности применения двух рабочих жидкостей с различными вязкоупругими характеристиками при гидродинамическом воздействии на призабойную зону пласта

Combination of hydrodynamic impact on the formation with acid treatment may be seen as a promising direction in the field of well development and repair in complex geological conditions. With multiple repetition of hydraulic shocks in conjunction with the injection of acid solution, the depth and opening of cracks gradually increases, which contributes to a deeper penetration of the acid solution into the reservoir. The article presents analytical studies, which are aimed at determining the effectiveness of applying the technology of hydrodynamic impact on the bottomhole zone of an oil reservoir when using two fluids with different viscoelastic characteristics as a working fluid. They are devoted to determining the pressure drop at the borehole bottom depending on the initial applied pressure at the wellhead, the velocity of the shock wave, the viscosity of the working and well fluid, and their quantity. These studies were based on the well-known models of Thomson – Tаt and Maxwell, considering viscous liquid flow. The dependence obtained proves that with an increase in the pressure pulse generated at the wellhead, the development of pressure pulses at the borehole bottom is a power-law dependence, and with significant volumes of fluid in contact with the bottomhole formation zone, the pressure drop generated at the borehole bottom does not depend only on pressure pulses generated at the wellhead, but also on the dynamic viscosity of this fluid. Conducted studies have shown the effectiveness of hydrodynamic impact technology application when using two liquids with different viscoelastic characteristics and obtaining a synergistic effect during the development and repair of wells in low-permeable reservoirs. Analytical studies were based on data from previously conducted experimental industrial tests on the operating injection well

Обоснование выбора винтовых насосных установок как энергоэффективной технологии механизированной добычи

The paper analyzes the main techniques and technologies of oil fluid recovery in the context of energy consumption, significantly rising over the latest decade. It is recognized that the number of publications in the area of energy efficiency is growing steadily. Currently Russian oil and gas industry are facing the task of accelerating reduction of energy consumption while preserving, or even increasing, production rates. The task is complicated by the fact that the majority of deposits in Russia either have already entered (primarily, Volga-Ural region) or are now entering (West Siberia) their last stage of exploration, whereas new deposits in East Siberia are only being brought into production. Furthermore, a lot of new deposits, which provide for high recovery rates, are profitable a priori as at the first stage of exploration they do not need any artificial lift due to their free flow production without any oil well pumps. However, there is a significant share of new deposits with low-permeability reservoirs, which require either a system of reservoir pressure maintenance or periodic hydraulic fracturing. At the same time deposits at the late stages of exploration, apart from the use of pump units, systems of reservoir pressure maintenance and hydraulic fracturing, require regular repair and restoration, measures against salt and heavy oil sediments, mechanical impurities, flooding, etc., which all has a negative effect on well profitability. In order to solve these problems, the authors review existing methods and calculate specific energy consumption using various pump systems for hypothetical wells, varying in yield. According to the research results, it has been revealed that from the point of view of energy efficiency, it is desirable to equip low- and low-yield wells with sucker rod progressive cavity pump units, medium-yield ones – with electric progressive cavity pumps driven by permanent magnet motor, medium- and high-yield wells – with electric progressive cavity pumps or electric submersible pumps driven by permanent magnet motor, depending on the characteristics of the pumpedout oil fluid

Электроснабжение станции нагрева нефти в скважине от ветроэлектрической установки

In this article, the authors reviewed a new technology to prevent the formation of asphalt-resin-paraffin deposits by the thermal method of electrothermal impact on the oil wellbore shaft using a wind-electric installation as an autonomous power source. The advantage of this thermal stimulation technique lies in its continuous nature, which will allow keeping the clear opening of the tubing constant. The scheme of the autonomous system for down-hole electric heating of oil is presented. A tubular or induction heater can serve as an electric heating element placed in the well. The heating element of the system can be used in the wells exploited by free-flow, gas lift and mechanized methods, while its installation does not require an overhaul. The paraffin oil saturation temperature and temperature distribution over the depth of the well were defined. The amount of heat, which must be transferred to the oil mixture in the tubing in order to ensure effective operation of the well, taking into account the dynamic state of the system, is calculated. The optimal depth of the heating element's location in the well and its power was determined. The calculation of the required power for wind-electric installation to maintain the set temperature in the wellbore was performed. Having conducted the studies, it was revealed that in order to prevent the asphalt-resin-paraffin deposits formation on the tubing walls of oil wells, it is expedient to use the in-line heater, which maintains the average steady-state temperature along the wellbore and at the wellhead above the initial crystallization point of the asphalt-resin-paraffin deposits. The application of the developed electrothermal system is relevant in the conditions of formation of asphalt-resin-paraffin deposits in the wellbore shaft at the fields, which do not have a connection to the centralized power grid

Электроснабжение станции нагрева нефти в скважине от ветроэлектрической установки

In this article, the authors reviewed a new technology to prevent the formation of asphalt-resin-paraffin deposits by the thermal method of electrothermal impact on the oil wellbore shaft using a wind-electric installation as an autonomous power source. The advantage of this thermal stimulation technique lies in its continuous nature, which will allow keeping the clear opening of the tubing constant. The scheme of the autonomous system for down-hole electric heating of oil is presented. A tubular or induction heater can serve as an electric heating element placed in the well. The heating element of the system can be used in the wells exploited by free-flow, gas lift and mechanized methods, while its installation does not require an overhaul. The paraffin oil saturation temperature and temperature distribution over the depth of the well were defined. The amount of heat, which must be transferred to the oil mixture in the tubing in order to ensure effective operation of the well, taking into account the dynamic state of the system, is calculated. The optimal depth of the heating element's location in the well and its power was determined. The calculation of the required power for wind-electric installation to maintain the set temperature in the wellbore was performed. Having conducted the studies, it was revealed that in order to prevent the asphalt-resin-paraffin deposits formation on the tubing walls of oil wells, it is expedient to use the in-line heater, which maintains the average steady-state temperature along the wellbore and at the wellhead above the initial crystallization point of the asphalt-resin-paraffin deposits. The application of the developed electrothermal system is relevant in the conditions of formation of asphalt-resin-paraffin deposits in the wellbore shaft at the fields, which do not have a connection to the centralized power grid