CORRELATIONS FOR ESTIMATING CHANGE IN RESIDUAL OIL SATURATION DURING LOW SALINITY WATER FLOODING

Abstract Handil Field is a giant mature oil and gas field situated in Mahakam Delta, East Kalimantan Indonesia. Peripheral Low Salinity Water injection was performed since 1978 with an extraordinary result. The paper is intending to describe the success story of this secondary recovery by low salinity water injection application in the peripheral of Handil field main zone, which successfully increased the oil recovery and brought down the remaining oil saturation beyond the theoretical value of residual oil saturation number. Water producer wells were drilled to produce low salinity water from shallow reservoirs 400 - 1000 m depth then it was injected to main zone reservoirs where the main accumulation of oil situated. This low salinity water reacted positively with the rock properties and in-situ fluids which was described as wettability alteration in the reservoir. It is related to initial reservoir condition, connate water saturation, rock physics and connate water salinity. This peripheral scheme then observed having the sweeping effect on top of pressure maintenance due to long period of injection. The field production performance was indicating the important reduction of residual oil saturation in some reservoirs with continuous low salinity water injection. From static Oil in Place calculation, some reservoirs have high current oil recovery up to 80%. This was proved by in situ residual oil saturation measurement which was performed in 2007 and 2011. It was indicating the low residual saturation as low as 8% - 15%. This excellent result was embraced by a progressive development plan, where water flooding with pattern and chemical injection will be performed later on. The continuation of this peripheral injection is in an on-going development with patterns injection which is called water flooding development. An important oil recovery can be achieved with a simple scheme of low salinity injection, performed in a close network injection, where the water treatment is simple yet significant oil gain was recovered. This innovation technique brings more revenue with less investment compared to chemical EOR injection.

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http://archives.datapages.com/data/ipa_pdf/2021/IPA21-BC-205.html

10.29118/ipa21-e-9 ◽

2021 ◽

Author(s):

J. Sianturi

Keyword(s):

Oil Recovery ◽

Water Injection ◽

Water Flooding ◽

Residual Oil ◽

Oil Saturation ◽

Residual Oil Saturation ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water ◽

Low Salinity Water Injection

Handil Field is a giant mature oil and gas field situated in Mahakam Delta, East Kalimantan Indonesia. Peripheral Low Salinity Water injection was performed since 1978 with extraordinary results. This paper describes the success story of this secondary recovery by low salinity water injection application in the peripheral of Handil field main zone, which successfully increased the oil recovery and brought down the remaining oil saturation beyond the theoretical value of residual oil saturation. Water producer wells were drilled to produce low salinity water from shallow reservoirs 400 - 1000 m depth then it was injected to main zone reservoirs where the main accumulation of oil is situated. This low salinity water reacted positively with the rock properties and in-situ fluids which is described as wettability alteration in the reservoir. It is related to initial reservoir condition, connate water saturation, rock physics and connate water salinity. This peripheral scheme then observed having the sweeping effect on top of pressure maintenance due to long period of injection. The field production performance was indicating the important reduction of residual oil saturation in some reservoirs with continuous low salinity water injection. From static Oil in Place calculation, some reservoirs have high current oil recovery up to 80%. This was proved by in situ residual oil saturation measurement which was performed in 2007 and 2011. It was indicating the low residual saturation as low as 8% - 15%. This excellent result was embraced by a progressive development plan, where water flooding with pattern and chemical injection will be performed later on. The continuation of this peripheral injection is in an on-going development with patterns injection which is called water flooding development. An important oil recovery can be achieved with a simple scheme of low salinity injection, performed in a close network injection, where the water treatment is simple yet significant oil gain was recovered. This innovation technique brings more revenue with less investment compared to chemical EOR injection.

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New Wettability Method for Sandstone Using High-Salinity/Low-Salinity Water Flooding at Residual Oil Saturation

10.2118/190464-ms ◽

2018 ◽

Cited By ~ 5

Author(s):

Hasan N. Al-Saedi ◽

Ali K. Alhuraishawy ◽

R. E. Flori ◽

P. V. Brady ◽

P. Heidari ◽

...

Keyword(s):

High Salinity ◽

Water Flooding ◽

Residual Oil ◽

Oil Saturation ◽

Residual Oil Saturation ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water

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Capillary desaturation curve: does low salinity surfactant flooding significantly reduce the residual oil saturation?

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-020-01074-1 ◽

2021 ◽

Author(s):

Davood Zivar ◽

Peyman Pourafshary ◽

Nikoo Moradpour

Keyword(s):

Hybrid Method ◽

Capillary Number ◽

Residual Oil ◽

Surfactant Flooding ◽

Oil Saturation ◽

Residual Oil Saturation ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water ◽

The Difference

AbstractDifferent oil displacement experiments conducted on sandstone and carbonate samples show that low salinity water (LSW) injection can reduce the residual oil saturation (ROS). Recently, surfactant flooding (SF) in combination with low salinity water (known as low salinity surfactant (LSS) flooding) is proposed as a potentially promising hybrid enhanced oil recovery (EOR) process. A lower ROS is reported for a LSS process compared to that seen in SF or with LSW at the same capillary number. The capillary desaturation curve (CDC) is a well-known tool to study the effect of viscous and capillary forces on ROS for different EOR techniques. In this study, ROS data of various LSW, SF, and LSS flooding experiments at different capillary numbers are collected to develop a CDC to analyze the performance of the hybrid LSS method. This can help to analyze the effect of the hybrid method on an extra improvement in sweep efficiency and reduction in residual oil. A lower ROS is observed for LSS compared to LSW and SF in the same capillary number range. Our study shows different behaviors of the hybrid method at different ranges of capillary numbers. Three regions are identified based on the capillary number values. The difference in ROS is not significant in the first region (capillary number in the range of 10−7–10−5), which is not applicable in the presence of surfactant due to the low interfacial tension value. A significant reduction in ROS is observed in the second region (capillary number in the range of 10−5–10−2) for LSS compared to SF. This region is the most practical range for SF and LSS flooding. Hence, the application of LSS provides a noticeable benefit compared to normal EOR techniques. In the third region (capillary numbers greater than 10−2), where the surfactant flooding is a better performer, the difference in ROS is negligible.

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Mysteries behind the Low Salinity Water Injection Technique

Journal of Petroleum Engineering ◽

10.1155/2014/304312 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 9

Author(s):

Emad Waleed Al-Shalabi ◽

Kamy Sepehrnoori ◽

Gary Pope

Keyword(s):

Relative Permeability ◽

Oil Recovery ◽

History Matching ◽

Water Injection ◽

Residual Oil ◽

Oil Saturation ◽

Low Salinity ◽

Low Salinity Water ◽

Salinity Water ◽

Low Salinity Water Injection

Low salinity water injection (LSWI) is gaining popularity as an improved oil recovery technique in both secondary and tertiary injection modes. The objective of this paper is to investigate the main mechanisms behind the LSWI effect on oil recovery from carbonates through history-matching of a recently published coreflood. This paper includes a description of the seawater cycle match and two proposed methods to history-match the LSWI cycles using the UTCHEM simulator. The sensitivity of residual oil saturation, capillary pressure curve, and relative permeability parameters (endpoints and Corey’s exponents) on LSWI is evaluated in this work. Results showed that wettability alteration is still believed to be the main contributor to the LSWI effect on oil recovery in carbonates through successfully history matching both oil recovery and pressure drop data. Moreover, tuning residual oil saturation and relative permeability parameters including endpoints and exponents is essential for a good data match. Also, the incremental oil recovery obtained by LSWI is mainly controlled by oil relative permeability parameters rather than water relative permeability parameters. The findings of this paper help to gain more insight into this uncertain IOR technique and propose a mechanistic model for oil recovery predictions.

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Investigation of Clay Type on Low Salinity Water Flooding Using a Glass Micromodel

Frontiers in Energy Research ◽

10.3389/fenrg.2020.600448 ◽

2020 ◽

Vol 8 ◽

Author(s):

Xuemei Wei ◽

Wenchao Jiang ◽

Yanyu Zhang ◽

Zhao Wang ◽

Xiaojun Li ◽

...

Keyword(s):

Zeta Potential ◽

Clay Minerals ◽

Oil Recovery ◽

Wetting Angle ◽

Water Flooding ◽

Residual Oil ◽

Low Salinity ◽

Low Salinity Water ◽

Displacement Experiments ◽

Salinity Water

Clay minerals are usually regarded as an important factor affecting the results of low salinity water (LSW) flooding. However, experiments on clay minerals are mainly in qualitative stage, the mechanism of clay minerals has not been studied completely. In this paper, Zeta potential of four kinds of clay minerals (montmorillonite; chlorite; illite; kaolinite) in different brine was measured, microscopic models of these clay minerals were made to measured wetting angle in different brine, and montmorillonite and kaolinite were chosen to conduct microscopic displacement experiments through customized micro-glass etching models. From experiment results, the following conclusions can be get: 1). With the decrease of salinity of injected water, the negative zeta potential of clay minerals increases and the wetting angle decreases. 2). Clay minerals are more sensitive to monovalent Na+ than bivalent Ca2+. 3). The results of microscopic experiments show that LSW can effectively improve oil recovery, whether kaolinite or montmorillonite. The recovery of montmorillonite is better with a relatively high salinity of LSW and kaolinite is better with a relatively low salinity of LSW. The mechanism of LSW improves kaolinite recovery factor is the change of wettability while that of montmorillonite is the increase of water phase wettability. However, a lot of droplet-like residual oil cannot be displaced in the montmorillonite throat. In filed production, both kaolinite-rich and montmorillonite-rich reservoirs are suitable for LSW flooding to improve oil recovery. However, for kaolinite reservoirs, a lower salinity of injected water would produce a better result, while for montmorillonite reservoirs, residual oil droplets in the throat are noteworthy.

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