Research of Improving Water Injection Effect by Using Active SiO2 Nano-Powder in the Low-Permeability Oilfield

2010 ◽  
Vol 92 ◽  
pp. 207-212 ◽  
Author(s):  
Ke Liang Wang ◽  
Shou Cheng Liang ◽  
Cui Cui Wang

SiO2 nano-powder is a new type of augmented injection agent, has the ability of stronger hydrophobicity and lipophilicity, and can be adsorbed on the rock surface so that it changes the rock wettability. It can expand the pore radius effectively, reduce the flow resistance of injected water in the pores, enhance water permeability, reduce injection pressure and augment injection rate. Using artificial cores which simulated geologic conditions of a certain factory of Daqing oilfield, decompression and augmented injection experiments of SiO2 nano-powder were performed after waterflooding, best injection volume of SiO2 nano-powder under the low-permeability condition was selected. It has shown that SiO2 nano-powder inverted the rock wettability from hydrophilicity to hydrophobicity. Oil recovery was further enhanced after waterflooding. With the injection pore volume increasing, the recovery and decompression rate of SiO2 nano-powder displacement increased gradually. The best injected pore volume and injection concentration is respectively 0.6PV and 0.5%, the corresponding value of EOR is 6.84% and decompression rate is 52.78%. According to the field tests, it is shown that, in the low-permeability oilfield, the augmented injection technology of SiO2 nano-powder could enhance water injectivity of injection wells and reduce injection pressure. Consequently, it is an effective method to resolve injection problems for the low-permeability oilfield.

2014 ◽  
Vol 1073-1076 ◽  
pp. 2310-2315 ◽  
Author(s):  
Ming Xian Wang ◽  
Wan Jing Luo ◽  
Jie Ding

Due to the common problems of waterflood in low-permeability reservoirs, the reasearch of finely layered water injection is carried out. This paper established the finely layered water injection standard in low-permeability reservoirs and analysed the sensitivity of engineering parameters as well as evaluated the effect of the finely layered water injection standard in Block A with the semi-quantitative to quantitative method. The results show that: according to the finely layered water injection standard, it can be divided into three types: layered water injection between the layers, layered water injection in inner layer, layered water injection between fracture segment and no-fracture segment. Under the guidance of the standard, it sloved the problem of uneven absorption profile in Block A in some degree and could improve the oil recovery by 3.5%. The sensitivity analysis shows that good performance of finely layered water injection in Block A requires the reservoir permeability ratio should be less than 10, the perforation thickness should not exceed 10 m, the amount of layered injection layers should be less than 3, the surface injection pressure should be below 14 MPa and the injection rate shuold be controlled at about 35 m3/d.


2013 ◽  
Vol 779-780 ◽  
pp. 1457-1461
Author(s):  
Xian Wen Li ◽  
Chun Mei Xu ◽  
Fang Yuan Guo ◽  
Xing Hong Wang

This paper from the research of the porous medium pore structure characteristics of ultra-low permeability reservoir, combined the core flow test with reservoir characteristics analysis and fluid properties analysis studying the reservoir water injection development effect. The research results show that: the microscopic heterogeneity of ultra-low permeability reservoir is strong, pore connectivity of porous medium is poor, seepage throat is very fine and microcrack is growth. During the process of water injection development there exist particle migration phenomenon, could easily cause pore throat blockage, and lead to water injection pressure rebound. According to the research result targeted on the organic mud acid deep broken down experiment, the result shows that it can achieve the purpose of depressure and increasing injection rate.


2021 ◽  
Author(s):  
Sultan Ibrahim Al Shemaili ◽  
Ahmed Mohamed Fawzy ◽  
Elamari Assreti ◽  
Mohamed El Maghraby ◽  
Mojtaba Moradi ◽  
...  

Abstract Several techniques have been applied to improve the water conformance of injection wells to eventually improve field oil recovery. Standalone Passive flow control devices or these devices combined with Sliding sleeves have been successful to improve the conformance in the wells, however, they may fail to provide the required performance in the reservoirs with complex/dynamic properties including propagating/dilating fractures or faults and may also require intervention. This is mainly because the continuously increasing contrast in the injectivity of a section with the feature compared to the rest of the well causes diverting a great portion of the injected fluid into the thief zone which ultimately creates short-circuit to the nearby producer wells. The new autonomous injection device overcomes this issue by selectively choking the injection of fluid into the growing fractures crossing the well. Once a predefined upper flowrate limit is reached at the zone, the valves autonomously close. Well A has been injecting water into reservoir B for several years. It has been recognised from the surveys that the well passes through two major faults and the other two features/fractures with huge uncertainty around their properties. The use of the autonomous valve was considered the best solution to control the water conformance in this well. The device initially operates as a normal passive outflow control valve, and if the injected flowrate flowing through the valve exceeds a designed limit, the device will automatically shut off. This provides the advantage of controlling the faults and fractures in case they were highly conductive as compared to other sections of the well and also once these zones are closed, the device enables the fluid to be distributed to other sections of the well, thereby improving the overall injection conformance. A comprehensive study was performed to change the existing dual completion to a single completion and determine the optimum completion design for delivering the targeted rate for the well while taking into account the huge uncertainty around the faults and features properties. The retrofitted completion including 9 joints with Autonomous valves and 5 joints with Bypass ICD valves were installed in the horizontal section of the well in six compartments separated with five swell packers. The completion was installed in mid-2020 and the well has been on the injection since September 2020. The well performance outcomes show that new completion has successfully delivered the target rate. Also, the data from a PLT survey performed in Feb 2021 shows that the valves have successfully minimised the outflow toward the faults and fractures. This allows achieving the optimised well performance autonomously as the impacts of thief zones on the injected fluid conformance is mitigated and a balanced-prescribed injection distribution is maintained. This paper presents the results from one of the early installations of the valves in a water injection well in the Middle East for ADNOC onshore. The paper discusses the applied completion design workflow as well as some field performance and PLT data.


2012 ◽  
Vol 5 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Gustavo-Adolfo Maya-Toro ◽  
Rubén-Hernán Castro-García ◽  
Zarith del Pilar Pachón-Contreras. ◽  
Jose-Francisco Zapata-Arango

Oil recovery by water injection is the most extended technology in the world for additional recovery, however, formation heterogeneity can turn it into highly inefficient and expensive by channeling injected water. This work presents a chemical option that allows controlling the channeling of important amounts of injection water in specific layers, or portions of layers, which is the main explanation for low efficiency in many secondary oil recovery processes. The core of the stages presented here is using partially hydrolyzed polyacrylamide (HPAM) cross linked with a metallic ion (Cr+3), which, at high concentrations in the injection water (5000 – 20000 ppm), generates a rigid gel in the reservoir that forces the injected water to enter into the formation through upswept zones. The use of the stages presented here is a process that involves from experimental evaluation for the specific reservoir to the field monitoring, and going through a strict control during the well intervention, being this last step an innovation for this kind of treatments. This paper presents field cases that show positive results, besides the details of design, application and monitoring.


2012 ◽  
Vol 524-527 ◽  
pp. 1190-1195
Author(s):  
Jian Jun Liu ◽  
Quan Shu Li ◽  
Gui Hong Pei

Channeling flow frequently occurs during the high pressure water injection of low permeability reservoir. The injection process is complex and covers so many parameters of which the contribution to channeling flow is necessarily to be studied. In this paper, numerical simulation is combined with sensitivity analysis method to calculate the significance of the weight of parameters to the channeling flow. First the values of different parameters are produced by using Latin hypercube method; second, by using these parameters, finite element model have been established and simulated, and the quantity of channeling flow has been calculated; then Spearman rank relation is applied to measure the relation of parameters and channeling flow. The results states that, in 10 years continuous injection, the well spacing and injection pressure have significant impact on the channeling flow. This states that during the application of high pressure water injection, the pressure and well spacing should be controlled especially.


2013 ◽  
Vol 631-632 ◽  
pp. 140-144
Author(s):  
Li Li

In this paper, the produced water in Daqing oilfield was detected, includes the viscosity and concentration ratio of living polymer (LH-1), interfacial tension and swelling rate of particle polymer (LHP-1). And its adaptability in low permeable fracture core was also tested. The results show that the injection property is good if the living polymer (LH-1) and the particle polymer (LHP-1) are used together, the volume-expansion particle polymer can effectively plugging the high permeable layer in bottom of the reservoir and improve water injection profile. The best injection volume of LH-1is 0.32 PV, and enhances oil recovery rate is 18.4%.


2013 ◽  
Vol 680 ◽  
pp. 295-300
Author(s):  
Ye Fei Chen ◽  
Zi Fei Fan ◽  
Jun Ni ◽  
Yun Juan Li ◽  
Qing Ying Hou

Kenkiyak oilfield in kazakstan is a low porosity, extremely low permeability and overpressure carbonate reservoir. There are different reservoir and fracture characteristics in different region. The formation pressure decline seriously and water cannot be injected into the low permeability zone. Referring to the domestic and oversea research achievement, integrating regional geologic characteristics, numerical simulation results and reservoir engineering research results, we optimize a series of the development technology policy, including the reasonable gas and water injection modes and injection opportunity, the suitable well patterns and well spacing. Meanwhile, the development mode of energy supplement in the extremely low permeability and overpressure reservoir is explored.


2020 ◽  
Vol 10 (6) ◽  
pp. 6652-6668

Historically, smart water flooding is proved as one of the methods used to enhance oil recovery from hydrocarbon reservoirs. This method has been spread due to its low cost and ease of operation, with changing the composition and concentration of salts in the water, the smart water injection leads to more excellent compatibility with rock and fluids. However, due to a large number of sandstone reservoirs in the world and the increase of the recovery factor using this high-efficiency method, a problem occurs with the continued injection of smart water into these reservoirs a phenomenon happened in which called rock leaching. Indeed, sand production is the most common problem in these fields. Rock wettability alteration toward water wetting is considered as the main cause of sand production during the smart water injection mechanism. During this process, due to stresses on the rock surface as well as disturbance of equilibrium, the sand production in the porous media takes place. In this paper, the effect of wettability alteration of oil wetted sandstones (0.005,0.01,0.02 and 0.03 molar stearic acid in normal heptane) on sand production in the presence of smart water is fully investigated. The implementation of an effective chemical method, which is nanoparticles, have been executed to prevent sand production. By stabilizing silica nanoparticles (SiO2) at an optimum concentration of 2000 ppm in smart water (pH=8) according to the results of Zeta potential and DLS test, the effect of wettability alteration of oil wetted sandstones on sand production in the presence of smart water with nanoparticles is thoroughly reviewed. Ultimately, a comparison of the results showed that nanoparticles significantly reduced sand production.


Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Xiang Li ◽  
Yuan Cheng ◽  
Wulong Tao ◽  
Shalake Sarulicaoketi ◽  
Xuhui Ji ◽  
...  

The production of a low permeability reservoir decreases rapidly by depletion development, and it needs to supplement formation energy to obtain stable production. Common energy supplement methods include water injection and gas injection. Nitrogen injection is an economic and effective development method for specific reservoir types. In order to study the feasibility and reasonable injection parameters of nitrogen injection development of fractured reservoir, this paper uses long cores to carry out displacement experiment. Firstly, the effects of water injection and nitrogen injection development of a fractured reservoir are compared through experiments to demonstrate the feasibility of nitrogen injection development of the fractured reservoir. Secondly, the effects of gas-water alternate displacement after water drive and gas-water alternate displacement after gas drive are compared through experiments to study the situation of water injection or gas injection development. Finally, the reasonable parameters of nitrogen gas-water alternate injection are optimized by orthogonal experimental design. Results show that nitrogen injection can effectively enhance oil production of the reservoir with natural fractures in early periods, but gas channeling easily occurs in continuous nitrogen flooding. After water flooding, gas-water alternate flooding can effectively reduce the injection pressure and improve the reservoir recovery, but the time of gas-water alternate injection cannot be too late. It is revealed that the factors influencing the nitrogen-water alternative effect are sorted from large to small as follows: cycle injected volume, nitrogen and water slug ratio, and injection rate. The optimal cycle injected volume is around 1 PV, the nitrogen and water slug ratio is between 1 and 2, and the injection rate is between 0.1 and 0.2 mL/min.


2021 ◽  
Author(s):  
Abhinandan Kohli ◽  
Oscar Kelder ◽  
Ralph Castelijns ◽  
Rob van Eijs ◽  
Maxim Volkov

Abstract For maintenance of the reservoir pressures and enhanced oil recovery in oil producing formations, waterflooding is often implemented by the Operators. This is achieved by drilling injection wells or converting the oil producing wells into injectors. The injection wells are located at carefully selected points in the oilfield so that the water displaces as much oil as possible to the production wells before the water starts to break through. A significant saving in an oilfield development can be obtained by reducing the actual number of injecting wells and increasing each of the injector wells’ capacity for injection. Balancing the injection and produced volumes often involves injecting at high pressures leading to the fracture of the reservoir rocks along a plane intersecting the wellbore. This happens when injection pressure exceeds the minimal principal stress and the tensile strength of the rock, thereby creating a hydraulic fracture. With continuous injection, these fractures start propagating into the reservoir and may reach the reservoir caprock, which may decrease the integrity and possibly lead to out of zone injection. The study of evaluation of downhole fracture monitoring is divided into two parts. In the first part of the paper (Kohli, et al., 2021), a downhole verification approach to identify the fracture initiation point(s) is the focus. It describes the planning, execution and interpretation of the downhole data. This includes spectral acoustic monitoring and modelling of the temperature responses to quantify the injectivity profile. In this second part of the paper, the direct business impact is discussed by further integration of acoustic monitoring and temperature modeling data with detailed results from of fracture dimension (height) measurement by means of pressure fall off tests. Combined, both studies form an integrated approach that the operator took to prove that the fracture network propagation remains within the reservoir and that the top seal integrity is maintained.


Sign in / Sign up

Export Citation Format

Share Document