Improved capacitance model considering bottom-hole flowing pressure and interference between oil wells

With the continuous production of oil wells, the reservoir properties, such as permeability and porosity, are changing accordingly, and the reservoir heterogeneity is also enhanced. This development is vulnerable to the problem of the one-way advance of injected water and low efficiency of water flooding. The interwell connectivity between injection and production wells controls the flow capacity of the subsurface fluid. Therefore, the analysis of interwell connectivity helps to identify the flow direction of injected water, which is of great significance for guiding the profile control and water plugging in the later stage of the oilfield. In this study, based on the principle of mass conservation, a capacitance model considering the bottom-hole flowing pressure was established and solved by using the production dynamic data of injection–production wells. Then, the validity of the capacitance model was verified by numerical simulation, and the influences of well spacing, compression coefficient, frequent switching wells, injection speed, and bottom-hole flowing pressure on interwell connectivity were eliminated. Finally, a practical mine technique for inversion of connectivity between wells using dynamic data was developed. The advantage of this model is that the production dynamic data used in the modeling process are easy to obtain. It overcomes the shortcomings of previous models and has a wider range of applications. It can provide a theoretical basis for the formulation of profile control and water-plugging schemes in the high-water-cut period.

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Soft Computation Application: Utilizing Artificial Neural Network to Predict the Fluid Rate and Bottom Hole Flowing Pressure for Gas-lifted Oil Wells

10.2118/193052-ms ◽

2018 ◽

Author(s):

Mazen Bahaa ◽

Eissa Shokir ◽

Ismail Mahgoub

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Oil Wells ◽

Bottom Hole ◽

Bottom Hole Flowing Pressure ◽

Artificial Neural

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Method and Application of Reducing Pressure and Increasing Production in Nanometer Porous Coal Seam

Tobacco Regulatory Science ◽

10.18001/trs.7.5.2.27 ◽

2021 ◽

Vol 7 (5) ◽

pp. 4608-4620

Author(s):

Jia Liu ◽

Yinghong Liu ◽

Ruyong Feng ◽

Na Li

Keyword(s):

Coalbed Methane ◽

Simulation Method ◽

Gas Production ◽

Coal Seams ◽

Bottom Hole ◽

Stable Production ◽

Production Wells ◽

Bottom Hole Flowing Pressure ◽

Coalbed Methane Production ◽

Production Period

Objectives: In order to deeply analyze the feasibility of reducing pressure and increasing production of coalbed methane wells in nano-porous coal seams and clarify the principle of well selection. Methods: The sensitivity of bottom hole flowing pressure to coalbed methane production is analyzed by establishing productivity equation in stable production period of coalbed methane wells. Combined with the numerical simulation method, the drainage and production effect of L-1 well in the Block A is simulated after reducing the flowing pressure at the bottom of the well. Results: The results show that for CBM wells that have been put into production, the effect of increasing the production can be achieved by reducing the bottom hole flowing pressure, and when the bottom hole flowing pressure is large, reducing the bottom hole flowing pressure can obtain a larger increase in gas production. The cumulative gas production of Well L-1 can be increased by 110x104m3 compared with the previous measures, and the increase rate can reach 85%. Conclusion: Combining with the pressure-reducing and increasing production wells in the Block A, the applicable conditions for pressure-dropping and increasing production to increase the production of CBM wells are proposed, that is, continuous and stable drainage and production, and there is a certain height of liquid column between the moving liquid level and the coal roof before operation.

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Investigation on Circulating Path of Injected Water for High Water-Cut Oilfield

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1073-1076.2201 ◽

2014 ◽

Vol 1073-1076 ◽

pp. 2201-2204

Author(s):

Sui Ting Zhao ◽

Qi Li ◽

Xiao Ru He ◽

Kao Ping Song ◽

Ji Cheng Zhang

Keyword(s):

Mathematical Model ◽

Fuzzy Theory ◽

Water Injection ◽

High Water ◽

Water Flooding ◽

Profile Control ◽

Production Wells ◽

High Water Cut ◽

Water Cut ◽

Swept Volume

In this paper, the indexes have been determined for identifying ineffective injection-production circulation and corresponding mathematical model was constructed with fuzzy theory. Application examples show that this method is simple, fast and accurate. For high and extra-high water cut oilfields, because of the long-term erosion of injected water, there are some high penetrative channels between the injection and production wells, resulting in most injected water along the channel to cause the invalid injection and production, for which it is hard to increase water flooding swept volume, causing flooding and high water cut well and reducing oil production. To improve the effectiveness of water injection to achieve stable yields, it is important to take the measures of ineffective injection-production wells profile control, plugging and so on for fast and accurate identifying ineffective injection-production wells. To that end, this paper applied fuzzy theory to establishing the mathematical model for identifying ineffective injection-production wells.

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A Fuzzy Method to Judge Water Passages with Ineffective Injection-Production for Heterogeneous Sandstone Reservoir

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.524-527.1306 ◽

2012 ◽

Vol 524-527 ◽

pp. 1306-1309 ◽

Cited By ~ 1

Author(s):

Peng Xiao Sun

Keyword(s):

Mathematical Model ◽

Fuzzy Theory ◽

Water Injection ◽

High Water ◽

Water Flooding ◽

Profile Control ◽

Production Wells ◽

High Water Cut ◽

Water Cut ◽

Swept Volume

In this paper, the indexes have been determined for identifying ineffective injection production circulation and corresponding mathematical model was constructed with fuzzy theory. Application examples show that this method is simple, fast and accurate. For high and superhigh water cut oilfields, because of the long-term erosion of injected water, there are some high penetrative channels between the injection and production wells, resulting in most injected water along the channel to cause the invalid injection and production, for which it is hard to increase water flooding swept volume, causing flooding and high water cut well and reducing oil production. To improve the effectiveness of water injection to achieve stable yields, it is important to take the measures of ineffective injection-production wells profile control, plugging and so on for fast and accurate identifying ineffective injection-production wells. To that end, this paper applied fuzzy theory to establishing the mathematical model for identifying ineffective injection-production wells.

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Prediction of Bottom-Hole Flowing Pressure using general regression neural network

2014 International Conference on Computer and Information Sciences (ICCOINS) ◽

10.1109/iccoins.2014.6868849 ◽

2014 ◽

Cited By ~ 2

Author(s):

Paras Q. Memon ◽

Suet-Peng Yong ◽

William Pao ◽

Pau J. Seanl

Keyword(s):

Neural Network ◽

General Regression Neural Network ◽

Bottom Hole ◽

Bottom Hole Flowing Pressure ◽

General Regression

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DEVELOPMENT OF AN ASPHALT-RESIN-PARAFFIN DEPOSITS INHIBITOR AND SUBSTANTIATION OF THE TECHNOLOGICAL PARAMETERS OF ITS INJECTION INTO THE BOTTOM-HOLE FORMATION ZONE

Periódico Tchê Química ◽

10.52571/ptq.v17.n34.2020.793_p34_pgs_769_781.pdf ◽

2020 ◽

Vol 17 (34) ◽

pp. 769-781 ◽

Cited By ~ 2

Author(s):

Karina Shamilevna KHAIBULLINA ◽

Grigory Yurievich KOROBOV ◽

Aleksandr Viktorovich LEKOMTSEV

Keyword(s):

Core Material ◽

Hole Formation ◽

Technological Parameters ◽

Oil Saturation ◽

Bottom Hole ◽

Formation Zone ◽

Production Wells ◽

Bulk Model ◽

Corrosive Activity ◽

The Impact

The problem of the formation of asphalt-resin-paraffin deposits (ARPD) in oil fields within the “well – bottom-hole formation zone” system is still relevant. To prevent the formation of ARPD in the “bottom-hole formation zone – well” system, the ARPD inhibitors must have high adsorption and low desorption properties concerning the rock. The composition of inhibitors often includes surfactants. Nonionic surfactants, namely, polyesters, are widely used to prevent the formation of ARPD. However, currently, little is known about inhibitors with a combined effect, for example, possessing depressor-dispersing properties for ARPD. This work aimed to develop a combined inhibitor possessing not only depressor-dispersing properties but also having good adsorption and desorption properties to the rock to prevent the formation of ARPD. The paper presents the research results on the development of an ARPD inhibitor, as well as the effects of determination of its depressor dispersing, inhibiting, and corrosive properties; the temperature of oil saturation with paraffin is determined as well. The studies of the ARPD inhibitor adsorption were carried out by the static and dynamic methods. In contrast, the process of the inhibitor desorption was studied by oil filtering through a saturated sample of the rock using a bulk model and core material. The impact of the fluid flow rate on the inhibitor desorption rate was studied. The technological parameters of the ARPD inhibitor solution injection into the bottom-hole formation zone of production wells were calculated. The developed composition has high inhibiting properties concerning the ARPD, depressor dispersing properties, low corrosive activity for a metal surface, and is capable of lowering the temperature of oil saturation with paraffin.

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Formulation Development of High Strength Gel System and Evaluation on Profile Control Performance for High Salinity and Low Permeability Fractured Reservoir

International Journal of Analytical Chemistry ◽

10.1155/2017/2319457 ◽

2017 ◽

Vol 2017 ◽

pp. 1-9 ◽

Cited By ~ 5

Author(s):

Chengli Zhang ◽

Guodong Qu ◽

Guoliang Song

Keyword(s):

High Salinity ◽

Crosslinking Agent ◽

High Strength ◽

Gel Strength ◽

Water Flooding ◽

Low Permeability ◽

Control Performance ◽

Formulation Development ◽

Profile Control ◽

Gel System

For the large pores and cracks of reservoirs with low temperatures, high salinity, and low permeability, a new type of high strength gel ABP system is developed in this paper. The defects of conventional gels such as weak gel strength, no gelling, and easy dehydration are overcome under the conditions of low temperature and high salinity. The temperature and salt resistance, plugging characteristics, and EOR of the gel system are studied. Under the condition of 32°C and 29500 mg/L salinity, the ABP system formulation is for 0.3% crosslinking agent A + 0.09% coagulant B + 3500 mg/L polymer solution P. The results show that when the temperature was increased, the delayed crosslinking time of the system was shortened and the gel strength was increased. The good plugging characteristics of the ABP system were reached, and the plugging rate was greater than 99% in cores with different permeability. A good profile control performance was achieved, and the recovery rate was improved by 19.27% on the basis of water flooding. In the practical application of the gel system, the salinity of formation water and the permeability of fractures are necessary to determine the appropriate formulation.

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A Calculation Method for Bottom Hole Flowing Pressure Based on Radial Basis Function

Journal of Convergence Information Technology ◽

10.4156/jcit.vol7.issue12.10 ◽

2012 ◽

Vol 7 (12) ◽

pp. 76-84

Author(s):

Jun Ni ◽

Zhanli Ren

Keyword(s):

Radial Basis Function ◽

Basis Function ◽

Calculation Method ◽

Bottom Hole ◽

Radial Basis ◽

Bottom Hole Flowing Pressure

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Role of Gas Viscosity for Shale Gas Percolation

Geofluids ◽

10.1155/2020/8892461 ◽

2020 ◽

Vol 2020 ◽

pp. 1-10

Author(s):

Xiaoming Wang ◽

Junbin Chen ◽

Dazhong Ren ◽

Zhaolong Shi

Keyword(s):

Pressure Drop ◽

Shale Gas ◽

Double Porosity ◽

Gas Viscosity ◽

Important Index ◽

Bottom Hole ◽

Fracture Systems ◽

Bottom Hole Flowing Pressure ◽

Porosity Model

Viscosity is an important index to evaluate gas flowability. In this paper, a double-porosity model considering the effect of pressure on gas viscosity was established to study shale gas percolation through reservoir pressure, gas velocity, and bottom hole flowing pressure. The experimental results show that when pressure affects gas viscosity, shale gas viscosity decreases, which increases the percolation velocity and pressure drop velocity of the free state shale gas in matrix and fracture systems. And it is conducive to the desorption of adsorbed shale gas and effectively supplemented the bottom hole flowing pressure with the pressure wave propagation range and velocity increasing, so that the rate of pressure drop at the bottom of the well slows down, which makes the time that bottom hole flowing pressure reaches stability shortened. Therefore, the gas viscosity should be fully considered when studying the reservoir gas percolation.

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