Research and Application of Tapping Potential Remaining Oil of Low Permeability Reservoir in Hei47 Block, Jilin Oilfield

2013 ◽  
Vol 663 ◽  
pp. 753-758 ◽  
Author(s):  
Fang Ding ◽  
Xu Yang

At present, Hei47 block has already entered high water cut period, and it exists many problems, such as imbalance producing reserves, serious water flooded in main small layer, imperfect injection-production well spacing and so on. Aiming at these problems, this paper analyzed from two aspects of the potential: the first is the potentiality of well pattern thickening which would analyze the reasons of the remaining oil enrichment through four different imperfect patterns, the paper proposes different schemes. For example, this study design new wells in the injection-production incongruous area; As for the area without the control of well net, for example, the study design a horizontal well near the fault where concentrated much remaining oil, and the production conditions are good; The second is making some modification measures in high water cut layer, and perforating other potential small layers, in the light of the wells in low location and is high water cut can be considered to transfer to injection wells. Structural reservoir high-yielding well mainly concentrated in the structural high place, flooded well in the low position, this area is suitable for edge water injection.

2020 ◽  
Vol 12 (1) ◽  
pp. 1736-1749
Author(s):  
Jincai Wang ◽  
Zifei Fan ◽  
Lun Zhao ◽  
Li Chen ◽  
Jun Ni ◽  
...  

Abstract After a sandstone oilfield enters the high water-cut period, the viscosity of crude oil has an important influence on remaining oil distribution and waterflooding characteristics under the same factors of, e.g., reservoir quality and development methods. Based on a comprehensive interpretation of the waterflooded layers in new oil wells, physical simulation experiments, and reservoir numerical simulations, we analyzed the waterflooding laws of a high water-cut sandstone reservoir with different oil viscosities in Kazakhstan under the same oil production speed, and we clarified the remaining oil potential of reservoirs with different viscosities and proposed corresponding development measures. The results show that low-viscosity oil reservoirs (1 mPa s) have uniform waterflooding, thick streamlines, small waterflooding areas, and low overall waterflooding degrees because of their homogeneous oil–water viscosities. However, within waterflooded areas, the reservoirs have high oil displacement efficiencies and high waterflooding degrees, and the remaining oil is mainly concentrated in the unwaterflooded areas; therefore, the initial production and water cut in new oil wells vary significantly. High-viscosity oil reservoirs (200 mPa s) have severe waterflooding fingering, large waterflooding areas, and high overall waterflooded degrees because of their high oil–water mobility ratios. However, within waterflooded areas, the reservoirs have low oil displacement efficiencies and low waterflooding degrees, and the remaining oil is mainly concentrated in both the waterflooded areas and the unwaterflooded areas; therefore, the differences in the initial production and water cut of new oil wells are small. Moderate-viscosity oil reservoirs (20 mPa s) are characterized by remaining oil distributions that are somewhere in between those of the former two reservoirs. Therefore, in the high water-cut period, as the viscosity of crude oil increases, the efficiency of waterflooding gradually deteriorates and the remaining oil potential increases. In the later development, it is suggested to implement the local well pattern thickening in the remaining oil enrichment area for reservoirs with low viscosity, whereas a gradual overall well pattern thickening strategy is recommended for whole reservoirs with moderate and high viscosity. The findings of this study can aid better understanding of waterflooding law and the remaining oil potential of reservoirs with different viscosities and proposed corresponding development measures. The research results have important guidance and reference significance for the secondary development of high water-cut sandstone oilfields.


Author(s):  
Yanlai Li ◽  
Jie Tan ◽  
Songru Mou ◽  
Chunyan Liu ◽  
Dongdong Yang

AbstractFor offshore reservoirs with a big bottom water range, the water cut rises quickly and soon enters the ultra-high water cut stage. After entering the ultra-high water cut stage, due to the influence of offshore production facilities, there are few potential tapping measures, so it is urgent to explore the feasibility study of artificial water injection development. The quasi-three-dimensional and two-dimensional displacement experiments are designed using the experimental similarity criteria according to the actual reservoir parameters. Several experimental schemes are designed, fluid physical properties, interlayer distribution, and development mode according to the actual reservoir physical properties. Through the visualization of experimental equipment, the bottom water reservoir is visually stimulated. The displacement and sweep law of natural water drive and artificial water injection in bottom water reservoir with or without an interlayer, different viscosity, and different well spacing is analyzed. The following conclusions are obtained: (1) For reservoirs with a viscosity of 150 cp. The recovery factor after water injection is slightly higher than before water injection. However, the recovery factor is lower than that without injection production. The reason is that the increment of injection conversion is limited to reduce one production well after injection conversion. (2) For reservoirs with a viscosity of 30 cp. The recovery factor after injection is 39.8%, which is slightly higher than 38.9% without injection. (3) For reservoirs with a viscosity of 150 cp. In the case of the interlayer. The recovery factor after injection is 30.7%, which is significantly higher than 24.8% without injection. (4) After the well spacing of the low-viscosity reservoir is reduced, the recovery factor reaches 46.1%, which is higher than 38.9% of the non-infill scheme. After the infill well in a low-viscosity reservoir is transferred to injection, the recovery factor is 45.6%, which has little change compared with non-injection, and most of the cumulative production fluid is water. The feasibility and effect of water flooding in a strong bottom water reservoir are demonstrated. This study provides the basis for the proposal of production well injection conversion and the adjustment of production parameters in the highest water cut stage of a big bottom water reservoir.


Author(s):  
Kuiqian Ma ◽  
Ao Li ◽  
Shuhao Guo ◽  
Jieqiong Pang ◽  
Yongchao Xue ◽  
...  

The multi-layer co-exploitation method is often used in offshore oilfields because of the large spacing between the injection and production wells. As oilfields gradually enter the high water-cut stage, the contradiction between the horizontal and vertical directions becomes more prominent, and the distribution of the remaining oil is more complex. Oilfields are facing unprecedented challenges in further enhancing oil recovery. Using oilfield A, which is in the high water-cut stage, as the research object, we compiled a detailed description of the remaining oil during the high water-cut stage using the information collected during the comprehensive adjustment and infilling of the oilfield. In addition various techniques for tapping the potential reservoir, stabilizing the oil, and controlling the water were investigated. A set of key techniques for the continuous improvement of the efficiency of water injection after comprehensive adjustment of high water-cut fields was generated. Based on the determined configuration of the offshore deltaic reservoir, a set of detailed descriptive methods and tapping technology for extracting the remaining oil in the offshore high water-cut oilfield after comprehensive adjustment was established. By considering the equilibrium displacement and using a new quantitative characterization method that includes displacement, a new technique for determining the quantity of water that needs to be injected into a stratified injection well during the high water-cut stage was established. Based on the principle of flow field intensity reconfiguration, a linear, variable-intensity, alternating injection and withdrawal technique was proposed. With the application of this series of techniques, the increase in the water content was controlled to within 1%, the natural reduction rate was controlled to within 9%, and the production increased by 1.060 × 107 m3.


2014 ◽  
Vol 522-524 ◽  
pp. 1346-1350
Author(s):  
Jian Huai Wang ◽  
Wei Nan Zhang

Taking M reservoir of D field as an example, analyzing the development feature of a thick sandstone reservoir in the high water cut stage which is driven by natural water, and studying the distribution law of remaining oil for this reservoir through 3 aspects: sweeping of the edge-bottom water, completeness of the well pattern and barrier of the partial interbed, and expounding the development method and effect of this thick sand reservoir in the high water cut stage through exploiting 3 kinds of remaining oil rich regions as fellows: the region which is not swept by the edge-bottom water; incomplete region of the well pattern and barrier region of the partial interbed.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Gaocheng Feng ◽  
Yuhui Zhou ◽  
Weiying Yao ◽  
Lingtong Liu ◽  
Zhao Feng ◽  
...  

Most multilayer sandstone reservoirs in the Bohai Sea have already entered the middle or high water cut production stage with large amounts of remaining oil being scattered distributed. Therefore, there is an urgent need to find a suitable countermeasure to reduce water cut and increase oil recovery. In this study, taking the narrow-channel reservoirs in the M oilfield as an example, we qualitatively described the sand body scale and the contact relationships between different sand bodies, in addition to carefully analyzing the material base and remaining oil distribution characteristics. Accordingly, we proposed a countermeasure based on the injection-production structural adjustment to reduce water cut and increase oil recovery from high water cut, narrow-channel reservoirs. Herein, three optimization strategies were developed based on the proposed development mode: a seepage field optimization strategy was developed based on the quantified injection-production index; a well pattern optimization strategy for narrow-channel reservoirs was developed to overcome the production energy refueling problem; an injection-production measure optimization strategy was developed to tap the different types of remaining oil. Additionally, the well pattern optimization and injection-production optimization strategies were integrated to optimize and adjust the seepage field system. The findings reported herein this paper help understand the development of similar offshore oilfields with a high water cut.


2013 ◽  
Vol 734-737 ◽  
pp. 1131-1134
Author(s):  
Jian Zhong Liu ◽  
Jin Cheng Xu

The remaining oil distribution and its potential evaluation are the keys to the well network adjustments and comprehensive potential exploration on the later stage production. In view of the vagueness of the influence factors of remaining oil potentiality, a set of quantitative evaluate method about how to suit remaining oil potentiality of heavy oil reservoir at high water-cut stage is established. Six factors are taken into consideration, including oil saturation, reservoir thickness, permeability, porosity, water injection distance and sedimentary facies. First, make sure the evaluate criterion and the influence weight of a single effect factor. And then, use the fuzzy theory to calculate the latent capacity of the block, comprehending many factors. In the end, certain the foundation of remaining oil potentialities according to the value of the latent capacity. Using this method, remaining oil potentiality of the east of Beierxi is calculated at high water cut period. This provides a theoretical guide to formulation and implementation of the in-situ potential measurement.


2021 ◽  
Author(s):  
Hongfu Shi ◽  
Yingxian Liu ◽  
Lifu Jiang ◽  
Jingding Zheng ◽  
Liqin Gan

Abstract Abundant faults, long oil-bearing intervals (up to 500m), and diverse fluids including conventional oil and heavy oil, result in P oilfield became one of the most complex oil fields in the Bohai Bay. The main characters ofinitial development plan are directional well with commingle production, open hole completion, large draw down, high oil production rate, and reverse nine-point well pattern. At present, the oilfield has entered a stage of high water cut, with average water cut more than 85%. What can we do next, decommissioning or rebirthing? An integrated solution was proposed to redevelop the oilfield which focus on the layers’ subdivision, the fine description of the sand body,a large number of horizontal wells on the top of the water-flooded layer are used to tap the potential, increase the water injector to transform the stream lines and rebuild the reservoir pressure, and search for potential sand bodies to increase reserves.


2014 ◽  
Vol 628 ◽  
pp. 348-353
Author(s):  
Tao Li ◽  
Zian Li ◽  
Jiang Wang

Sanan oilfield has entered late stage of high water cut development. It urgently needs accurate prediction of remaining oil distribution. But previous studies on 3D structure were far could not meet the requirements of fine reservoir description. This paper applied RMS, a piece of excellent geological modeling software establishing the 3D fine structural model of typical block in Sanan oilfield on the bases of 3D fine seismic structural interpretation data. It included the 28 faults’ model, 11 horizons’ model and the structural model. And then measured and analyzed the faults elements data. Based on abundant geologic data, well data and seismic data of the block, this structural model reproduced the fine seismic interpretation results accurately. It was really fine enough to meet the requirements of the fine reservoir description. This research solved the problem that traditional modeling techniques could not handle complex cutting relationship of faults’ model. It laid a solid foundation for reservoir numerical simulation and remaining oil distribution prediction.


2021 ◽  
Vol 19 (3) ◽  
pp. 848-853
Author(s):  
Liliya Saychenko ◽  
Radharkrishnan Karantharath

To date, the development of the oil and gas industry can be characterized by a decline in the efficiency of the development of hydrocarbon deposits. High water cut-off is often caused by water breaking through a highly permeable reservoir interval, which often leads to the shutdown of wells due to the unprofitability of their further operation. In this paper, the application of straightening the profile log technology for injection wells of the Muravlenkovsky oil and gas field is justified. In the course of this work, the results of field studies are systematized. The reasons for water breakthrough were determined, and the main ways of filtration of the injected water were identified using tracer surveys. The use of CL-systems technology based on polyacrylamide and chromium acetate is recommended. The forecast of the estimated additional oil produced was made.


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