Design, Operation, and Laboratory Work for Single-Well Tracer Test Campaign in Handil Field Indonesia

Abstract

This paper focuses on the design, the operation and the laboratory work needed for performing a successfull Single Well Tracer Test (SWTT) campaign in the Handil mature field Indonesia. Three tests have been performed in different waterflooded reservoirs to assess the repartition of Remaining Oil Saturation (ROS) in the field. An extensive laboratory work has been performed prior to tests to screen chemicals that could be used and then to measure the two main parameters needed for the design of the tests: the partitioning coefficient of the primary tracer between water and oil (Kd) and the hydrolysis reaction rate (kH) of the primary tracer into the water. Measurements were performed at reservoir temperature and pressure conditions using recombined live oil sample and recombined brine with respect to the salinity of each reservoir. Results indicate very low discrepancy of Kd value between reservoirs (4 to 5), while kH show a strong linear dependency with salinity (from 0.12 to 0.45 day−1). To take into account the presence of trapped gas saturation, we measured also the partitioning coefficient of AcOET between the water and the gas phase at reservoir pressure and temperature. As expected the Kd water/gas was low compare to the water/oil with a value of 0.5. Tests were performed in parallel after the installation and the calibration of laboratory equipments and the commissionning of the injection barge. The tracer profiles quality recorded from the three tests was very good with high tracer recovery and low scattering data. However the interpretation was challenging, and numerical simulation was necessary to handle non ideal phenomenan occurring during these tests and to get reliable ROS estimation. The ROS values range between 20-30% which allows moving forward in the identification of potential EOR reservoir candidates and locations of future pilot zones for the more promising EOR processes.

The Value of Inter-well and Single Well Tracer Technology for De-Risking and Optimizing a CEOR Process - Caracara Field Case

“…This phenomenon is known as chromatographic separation. The distribution of the partitioning tracer is governed by the partitioning coefficient (Kd) which can be measured accurately in the laboratory at reservoir conditions (Deans et al 1986, Mechergui et al 2013, Callegaro et al 2014.…”

Численно-Аналитическая Модель Для Интерпретации Результатов Индикаторных Исследований Нефтяных Пластов: Решение Прямой Задачи При Наличии Каналов Низкого Фильтрационного Сопротивления

“…Односкважинный трассерный тест запатентован еще в начале 1970-х годов [12], но получил распространение лишь в последнее время, с расширением практики применения методов увеличения нефтеотдачи [13][14][15]. Многочисленные публикации показывают следующие качественные и количественные результаты.…”

Evaluation of the Kinetic and Thermodynamic Behavior of Tracers for Their Applicability in SWCTT

“…Compared to expensive well logging operations or complex core studies, an alternative way to determine the oil saturation used in the field is through single-well tracer studies (having a larger exploration radius ~3-7 m) [4,5]. The single-well chemical tracer test (SWCTT) technology, used to evaluate the efficiency of EOR, makes it possible to measure oil saturation by injecting substances (usual esters) partitioned between phases (oil-water) into the reservoir through a production well, which undergo a hydrolysis reaction to form a secondary tracer (alcohol) and acid during a well shut-in time [2,[4][5][6]. The duration of the well shut-in depends on the reactivity of the primary tracer in reservoir conditions.…”

“…Since the secondary tracer, alcohol, does not dissolve in oil, it is extracted before the ester, which is predominantly in oil. Based on the difference in the arrival time to the wellhead between the two tracers and the K-value, the residual oil saturation S or is calculated [5,6]:…”