«Oilfield engineering»

INDIRECT METHODS FOR ESTIMATING CURRENT FORMATION PRESSURE IN A WELL TO BE APPLIED WHEN BUILDING INTEGRATED MODELS OF FIELDS

UDC: 622.276.26
DOI: 10.33285/0207-2351-2021-7(631)-39-45

Authors:

¹ LUKOIL-Engineering Limited PermNIPIneft Branch Office in Perm, Perm, Russian Federation

Keywords: geological and hydrodynamic model, hydrodynamic studies of wells, integrated model, productivity factor, well model, regression analysis, reservoir pressure

Annotation:

Integrated models building is based on the use of up-to-date initial data for modeling the process of oil production. Due to the inability to estimate reservoir pressure using hydrodynamic studies (HDT) with the required discreteness, outdated information is often used in well models, which, in turn, affects the accuracy of predictive calculations. Up-to-date reservoir pressure data are required to improve the quality of the models. The paper provides an assessment of the indirect methods applicability for determining the current reservoir pressure in a well for use when building integrated field models in the Petroleum Experts software. The following methods are highlighted: regression analysis, the use of Prosper, the use of a geological and hydrodynamic model (GGDM). The regression analysis is based on finding the most important factors affecting the dependent variable. The method is applicable if there are more than three measurements of reservoir pressure in the well for the period under consideration and there have been no changes in the reservoir development mode since the last study (for example, the introduction of a reservoir pressure maintenance system). The result of the analysis is a mathematical model for estimating the formation pressure in the well, which makes it possible to determine the value based on the known parameters. Reservoir pressure assessment using Prosper is possible if the well has been subjected to at least one hydrodynamic test conducted no more than a year ago, and no measures affecting the productivity of the well have been carried out since the last survey. The use of GGDM allows estimating the reservoir pressure provided that the well is adjusted by at least one actual value during the period of operation. To assess the applicability of the methods under consideration, they were tested in the wells of LLC "LUKOIL-PERM" field, including the calculation of reservoir pressure values and comparison of the obtained data with actual data. Based on the comparison results, the average error of each method was calculated. When determining the reservoir pressure of the field’s entire well stock, it is reqired to use indirect methods in aggregate. For this purpose, an algorithm has been formed that allows selection for each well of a suitable method with the smallest error, based on the availability of the initial data. The algorithm has been tested in production wells of 14 fields of LLC "LUKOIL-PERM".

Bibliography:

1. Ерофеев А.А., Пономарева И.Н., Мордвинов В.А. К определению пластового давления при гидродинамических исследованиях скважин в карбонатных коллекторах // Нефт. хоз-во. - 2011. - № 4. - С. 98-100.
2. Унгуряну Т.Н., Гржибовский А.М. Корреляционный анализ с использованием пакета статистических программ STATA // Экология человека. - 2014. - № 9. - С. 60-64.
3. Коновалов Ю.В. Статистическое моделирование с использованием регрессионного анализа: методические указания к выполнению курсовой работы по дисциплине "Компьютерное и статистическое моделирование". - М.: МГТУ им. Н.Э. Баумана, 2013.
4. Марченко Б.И. Здоровье на популяционном уровне: статистические методы исследования: руководство для врачей. - М.: Cфинкс, 1997. - 432 с.
5. Орлов А.И. Ошибки при использовании коэффициентов корреляции и детерминации // Заводская лаборатория. Диагностика материалов. - 2018. - Т. 84, № 3. - С. 68-72.
6. Курзаева Л.В. Регрессионный анализ в электронных таблицах // Международный журнал прикладных и фундаментальных исследований. - 2016. - № 12-7. - С. 1234-1238.
7. Petroleum Experts User Manual IPM Prosper Version 16 // Petroleum Experts Ltd. - January 2020.
8. Лиа Д., Дунхам К., Роулан Л. Моделирование работы скважины: Оптимизация добычи и выявление устранение проблем с использованием метода узлового анализа // Российские нефтегазовые технологии. - 2007. - № 11. - С. 72-85.
9. Временный регламент оценки качества и приемки трехмерных цифровых геолого-гидродинамических моделей, представляемых пользователями недр в составе технических проектов разработки месторождений углеводородного сырья на рассмотрение ЦКР Роснедр по УВС: протокол ЦКР Роснедр по УВС от 19 апреля 2012 г. № 5370.