Derivation of water flooding characteristic curve for offshore low-amplitude structural reservoir with strong bottom water

AbstractThe water flooding characteristic curve method is one of the essential techniques to predict recoverable reserves. However, the recoverable reserves indicated by the existing water flooding characteristic curves of low-amplitude reservoirs with strong bottom water increase gradually, and the current local recovery degree of some areas has exceeded the predicted recovery rate. The applicability of the existing water flooding characteristic curves in low-amplitude reservoirs with strong bottom water is lacking, which affects the accurate prediction of development performance. By analyzing the derivation process of the conventional water flooding characteristic curve method, this manuscript finds out the reasons for the poor applicability of the existing water flooding characteristic curve in low-amplitude reservoir with strong bottom water and corrects the existing water flooding characteristic curve according to the actual situation of the oilfield and obtains the improvement method of water flooding characteristic curve in low-amplitude reservoir with strong bottom water. After correction, the correlation coefficient between $$\frac{{k_{ro} }}{{k_{rw} }}$$ k ro k rw and $$S_{w}$$ S w is 95.92%. According to the comparison between the actual data and the calculated data, in 2021/3, the actual water cut is 97.29%, the water cut predicted by the formula is 97.27%, the actual cumulative oil production is 31.19 × 104t, and the predicted cumulative oil production is 31.31 × 104t. The predicted value is consistent with the actual value. It provides a more reliable method for predicting low-amplitude reservoirs' recoverable ability with strong bottom water and guides the oilfield's subsequent decision-making.

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A New Growth Curve for Predicting Production Performance of Water-Flooding Oilfields

Mathematical Problems in Engineering ◽

10.1155/2021/7787850 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Feng Liu ◽

Yancheng Liu ◽

Xiao Guo ◽

Fei Yang ◽

Ahuan Zhou ◽

...

Keyword(s):

Growth Curve ◽

Growth Curves ◽

Oil Production ◽

Production Performance ◽

Water Flooding ◽

Production Data ◽

New Model ◽

Well Production ◽

Curve Method ◽

Water Cut

Oil production and water cut prediction is one of the most important research contents of reservoir production performance analysis. The growth curve method has the advantages of the general water drive curve method and the combined solution model method with fewer parameters and simple and fast calculation process and so it has been widely used in well production prediction. Based on the analysis of 4W and 4Y4 model growth curves, a new generalized growth curve of the well production performance is proposed. The new model can forecast cumulative oil production, annual oil production, and water cut at different oilfield development periods. A MATLAB program was developed to derive the parameters in the new model. The built model was applied to the production data of the Samattalol oilfield and Daqing oilfield. The predicted cumulative oil production, annual oil production, and water cut are all close to the actual production data, and satisfactory results are obtained, which demonstrates the practicability and reliability of the new model.

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Study on Effect Evaluation Method of Weak Gel Flooding Control in Ordinary Heavy Oil Reservoirs

E3S Web of Conferences ◽

10.1051/e3sconf/202021302020 ◽

2020 ◽

Vol 213 ◽

pp. 02020

Author(s):

Fachao Shan ◽

Lun Zhao ◽

Anzhu Xu ◽

Bing Bo ◽

Gang Ma ◽

...

Keyword(s):

Heavy Oil ◽

Evaluation Method ◽

Characteristic Curve ◽

Oil Reservoirs ◽

Water Flooding ◽

Effect Evaluation ◽

Application Range ◽

Heavy Oil Reservoirs ◽

Single Well ◽

Curve Method

Generally the dynamic methods are used to calculate the oil increase after flooding control in the oilfield, but the evaluation results of different methods are quite different, and the evaluation results are uncertain. Therefore, for flooding control well groups in heavy oil reservoirs, the water flooding characteristic curve method, decline method and net oil increase method are used to calculate the oil increase, and the influence of the method parameter values on the results are analyzed, and the parameter value limits and calculation errors of each method are determined. Based on this, the adaptability of each method is proposed. The results show that the effect evaluation of the whole region flooding control is suitable to use the water flooding characteristic curve method or the decline method, the effect evaluation of the single well group flooding control is more suitable to use the decline method, the net oil increase method is not recommended. The application range and parameter value limit of the effect evaluation method of flooding control are put forward, which can guide the actual production effect evaluation in the oilfield.

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A New Method of Plugging the Fracture to Enhance Oil Production for Fractured Oil Reservoir using Gel Particles and the HPAM/Cr3+ System

Polymers ◽

10.3390/polym11030446 ◽

2019 ◽

Vol 11 (3) ◽

pp. 446 ◽

Cited By ~ 6

Author(s):

Lei Zhang ◽

Nasir Khan ◽

Chunsheng Pu

Keyword(s):

Oil Recovery ◽

Oil Production ◽

Oil Reservoirs ◽

New Method ◽

Water Flooding ◽

Whole Process ◽

Gel Particles ◽

The Matrix ◽

Water Cut ◽

Enhance Oil Recovery

Due to the strong heterogeneity between the fracture and the matrix in fractured oil reservoirs, injected water is mainly moved forward along the fracture, which results in poor water flooding. Therefore, it is necessary to reduce the water cut and increase oil production by using the conformance control technology. So far, gel particles and partially hydrolyzed polyacrylamide (HPAM)/Cr3+ gel are the most common applications due to their better suitability and low price. However, either of the two alone can only reduce the conductivity of the fracture to a certain extent, which leads to a poor effect. Therefore, to efficiently plug the fracture to enhance oil recovery, a combination of gel particles and the HPAM/Cr3+ system is used by laboratory tests according to their respective advantages. The first step is that the gel particles can compactly and uniformly cover the entire fracture and then the fracture channel is transformed into the gel particles media. This process can enhance the oil recovery to 18.5%. The second step is that a suitable HPAM/Cr3+ system based on the permeability of the gel particles media is injected in the fractured core. Thus, the fracture can be completely plugged and the oil in the matrix of the fractured core can be displaced by water flooding. This process can enhance oil recovery to 10.5%. During the whole process, the oil recovery is increased to 29% by this method. The results show that this principle can provide a new method for the sustainable and efficient development of fractured oil reservoirs.

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New Waterflooding Characteristic Curves Based on Cumulative Water Injection

Mathematical Problems in Engineering ◽

10.1155/2020/7415236 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12

Author(s):

Zhiwang Yuan ◽

Zhiping Li ◽

Li Yang ◽

Yingchun Zhang

Keyword(s):

Characteristic Curve ◽

Water Injection ◽

Material Balance ◽

Oil Production ◽

High Water ◽

Difficult Problem ◽

Prediction Errors ◽

High Water Cut Stage ◽

High Water Cut ◽

Water Cut

When a conventional waterflooding characteristic curve (WFCC) is used to predict cumulative oil production at a certain stage, the curve depends on the predicted water cut at the predicted cutoff point, but forecasting the water cut is very difficult. For the reservoirs whose pressure is maintained by water injection, based on the water-oil phase seepage theory and the principle of material balance, the equations relating the cumulative oil production and cumulative water injection at the moderately high water cut stage and the ultrahigh water cut stage are derived and termed the Yuan-A and Yuan-B curves, respectively. And then, we theoretically analyze the causes of the prediction errors of cumulative oil production by the Yuan-A curve and give suggestions. In addition, at the ultrahigh water cut stage, the Yuan-B water cut prediction formula is established, which can predict the water cut according to the cumulative water injection and solve the difficult problem of water cut prediction. The application results show Yuan-A and Yuan-B curves are applied to forecast oil production based on cumulative water injection data obtained by the balance of injection and production, avoiding reliance on the water cut forecast and solving the problems of predicting the cumulative oil production of producers or reservoirs that have not yet shown the decline rule. Furthermore, the formulas are simple and convenient, providing certain guiding significance for the prediction of cumulative oil production and water cut for the same reservoir types.

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Mechanisms of water flooding characteristic curve upwarping at high water-cut stage and influencing factors

Chinese Science Bulletin (Chinese Version) ◽

10.1360/tb-2019-0132 ◽

2019 ◽

Vol 64 (26) ◽

pp. 2751-2760 ◽

Cited By ~ 1

Author(s):

Jun Yao ◽

Lei Zhang ◽

Hai Sun ◽

Tao Huang ◽

Yongfei Yang ◽

...

Keyword(s):

Influencing Factors ◽

Characteristic Curve ◽

High Water ◽

Water Flooding ◽

High Water Cut Stage ◽

High Water Cut ◽

Water Cut

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A Method to Determine the Optimal Water Injection Intensity Based on Oil Production Rate and Water Cut

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.2442 ◽

2012 ◽

Vol 594-597 ◽

pp. 2442-2445 ◽

Cited By ~ 1

Author(s):

Ji Cheng Zhang ◽

Ying Jia ◽

Xiao Na Cui

Keyword(s):

Production Rate ◽

Water Injection ◽

Oil Production ◽

Water Flooding ◽

Water Intensity ◽

Water Cut ◽

Relationship Of ◽

The Relationship ◽

Oilfield Development ◽

Zone Water

Water injection is one of the important ways to maintain reservoir pressure and improving the oilfield development effect. And separate zone water injection is the main technology in water flooding oilfield. The optimal water intensity which has been allocated plays an important role in all kinds of reservoir. This paper proposed a method to optimize the water injection intensity based on oil production rate and water cut. Conceptual model was constructed on the basis of real reservoir. By numerical simulation, a chart board was derived which describes the relationship of water injection intensity versus oil production rate and water cut. Using this chart, we can determine the optimal water injection intensity on different oil production rate and water cut.

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Low Permeability Reservoir Water Displacing Oil and Water Flooding Characteristic Curve Theory

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.556-562.4701 ◽

2014 ◽

Vol 556-562 ◽

pp. 4701-4704

Author(s):

Chun Sen Zhao ◽

Qing Lin Ren ◽

Pei Jing Li

Keyword(s):

Characteristic Curve ◽

Water Injection ◽

Oil Field ◽

Water Flooding ◽

Practical Significance ◽

Low Permeability ◽

Reservoir Water ◽

Field Development ◽

Recoverable Reserves ◽

The Impact

The so-called water flooding characteristic curve refers to the oilfield water injection (or natural water drive) development process, a relationship between curve cumulative oil production, cumulative water production and accumulation of fluid production. These curves have been widely used for water injection development of dynamic and recoverable reserves forecast. After many years of practical application, summed up the four kinds of water drive characteristic curve, they have a good practical significance. Recoverable reserves are important indicators of field development is the main basis for planning and design, the application of waterflooding characteristic curve can be predicted oil recoverable reserves. Four water flooding characteristics discussed above curve is mainly applied in high-permeability oil field, which did not consider starting pressure, but should consider the impact of low permeability oilfield actuating pressure gradient on the moisture content.

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Evaluating Water Coning Control for Horizontal Well in Bottom-Water Sandstone Reservoirs by Numerical Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.292 ◽

2012 ◽

Vol 524-527 ◽

pp. 292-296

Author(s):

Rong Wang ◽

Kui Zhang ◽

Yong Gang Duan ◽

Ting Kuan Cao

Keyword(s):

Horizontal Well ◽

Bottom Water ◽

Negative Impact ◽

Oil Production ◽

High Water ◽

Control Effect ◽

Water Coning ◽

Sandstone Reservoirs ◽

High Water Cut Stage ◽

Water Cut

Horizontal well is the main technology to develop bottom-water sandstone reservoirs. Water coning has a significant influence on development effect, and shut-in coning control is one of coning suppression methods. Based on the geological model of a given oilfield, this paper has made an evaluation of water coning control by numerical simulation. It can be concluded that the method of shut-in coning control is effective for low water cut wells. When shutting in, the lower the water cut is, the greater decline extent of water cut can be obtained and the higher cumulative oil production can be achieved after well reopening. The longer the close time is, the better water coning control effect can be acquired, however it will affect oil production undoubtly. When horizontal well enters into high water cut stage, shut-in coning control not only has almost no effect, but also has a negative impact on the normal oil production.

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Combined Oil Displacment System and Field Test of Composite Surfactant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.77 ◽

2013 ◽

Vol 641-642 ◽

pp. 77-81

Author(s):

Xiao Lin Wu ◽

Jian Jun Le ◽

Ming Jun Wang ◽

Wei Li ◽

Meng Hua Guo ◽

...

Keyword(s):

Field Test ◽

Oil Recovery ◽

Oil Production ◽

Water Flooding ◽

Laboratory Evaluation ◽

Reservoir Permeability ◽

Single Well ◽

Average Water ◽

Displacement System ◽

Water Cut

Laboratory evaluation showed that rhamnolipid combined displacement system with low and wide effective concentration (0.125%~1.0%) can reduce interfacial tension with Pubei oil and water to 10-2mN/m. Injection of 0.5PV of rhamnolipid combined displacement system in natural core simulating reservoir permeability can increase recovery by 7.9%~9.3% more than water flooding. Field test for rhamnolipid combined displacement system was carried out with 2 injectors and 9 producers. Alternating injection is performed with two slugs with total volume of 19895.5m3, containing 250.9t of dosage. During 13 months of field test, stageous cumulative incremental oil production was 2014t, with 224t of average single well incremental oil. Daily oil production increased from 1.5t/d to 1.85t/d, average water cut decreased by1.5%, and input-output ratio was 1:2.4. This study provided a new way to improve oil recovery for other similar water flooded reservoirs.

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