Improved oil recovery by raw water injection using horizontal wells

2009 ◽  
Vol 49 (1) ◽  
pp. 453
Author(s):  
Pavel Bedrikovetsky ◽  
Mohammad Afiq ab Wahab ◽  
Gladys Chang ◽  
Antonio Luiz Serra de Souza ◽  
Claudio Alves Furtado
Keyword(s):  
Oil Recovery ◽  
Filter Cake ◽  
Produced Water ◽  
Water Injection ◽  
Horizontal Wells ◽  
Water Flooding ◽  
Sweep Efficiency ◽  
Improved Oil Recovery ◽  
The North ◽  
Reservoir Simulator

Injectivity formation damage with water-flooding using sea/produced water has been widely reported in the North Sea, the Gulf of Mexico and the Campos Basin in Brazil. The damage is due to the capture of solid/liquid particles by the rock with consequent permeability decline; it is also due to the formation of a low permeable external filter cake. Yet, moderate injectivity decline is not too damaging with long horizontal injectors where the initial injectivity is high. In this case, injection of raw or poorly treated water would save money on water treatment, which is not only cumbersome but also an expensive procedure in offshore projects. In this paper we investigate the effects of injected water quality on waterflooding using horizontal wells. It was found that induced injectivity damage results in increased sweep efficiency. The explanation of the phenomenon is as follows: injectivity rate is distributed along a horizontal well non-uniformly; water advances faster from higher rate intervals resulting in early breakthrough; the retained particles plug mostly the high permeability channels and homogenise the injectivity profile along the well. An analytical model for injectivity decline accounting for particle capture and a low permeable external filter cake formation has been implemented into the Eclipse 100 reservoir simulator. It is shown that sweep efficiency in a heterogeneous formation can increase by up to 5% after one pore volume injected, compared to clean water injection.

Investigation of Significance of Critical Components in Optimization of WAG Injection Processes under Uncertainty

2014 ◽  
Author(s):  
C.. Temizel ◽  
S.. Purwar ◽  
A.. Agarwal ◽  
A.. Abdullayev ◽  
K.. Urrutia ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Large Fraction ◽  
Water Injection ◽  
Sweep Efficiency ◽  
Improved Oil Recovery ◽  
Injection Process ◽  
Water Alternating Gas ◽  
Gas Flooding ◽  
Reservoir Simulator ◽  
Wag Injection

Abstract Water alternating gas (WAG) injection has been widely used for the last 50 years throughout the world. The typical improved oil recovery (IOR) potential for WAG injection compared with water injection is 5 to 10%. It was originally intended to improve sweep efficiency during gas flooding, with intermittent slugs of water and gas designed to follow the same route through the reservoir. Mechanisms in WAG injection include microscopic effects, particularly in cases where three-phase flow and hysteresis are important for the IOR effect. Injection of gas usually aids an ongoing waterflood, and finding technical and commercial methods to reduce gas costs would be useful. Water injection alone tends to sweep the lower parts of a reservoir, while gas injected alone sweeps more of the upper parts of a reservoir because of gravitational forces. Gas represents a large fraction of the total cost, making WAG injection an expensive method. Thus, optimizing WAG injection is not only crucial in terms of recovery but also economics, especially where gas is expensive and/or limited. In this study, the significance of key components in a WAG injection process on SPE's 5th Comparative Solution Project (CSP) is presented that models the WAG process through a pseudo-miscible formulation by means of coupling a full-physics reservoir simulator with commercial optimization and uncertainty software. The results are analyzed and presented in a comparative manner by means of tornado charts showing the significance of each decision and uncertainty variable.

Use of Downhole Oil-Water Separation System in Horizontal Wells

2021 ◽  
Author(s):  
Ahmed Alshmakhy ◽  
Ali Abdelkerim ◽  
Nils Braaten
Keyword(s):  
Oil Recovery ◽  
Produced Water ◽  
Financial Analysis ◽  
Mechanical Design ◽  
Flow Simulation ◽  
Horizontal Wells ◽  
Processing Plant ◽  
Water Separation ◽  
Improved Oil Recovery ◽  
Water Cut

Abstract This paper will focus on a new system for separation of water in downhole horizontal wells. The advantages with the system are related to the fact that the water produced from the well is not lifted to the surface, but re-injected into suitable parts of the reservoir, either for pressure support or for diposal. The method of water separation and re-injection has been evaluated for oil producing fields. The paper presents details of the technical solutions and analysis done related to the financial analysis/payback. The mechanical design is basically a main pipe section of a few meters of length, with a special geometry utilizing gravity-based separation. A technical and economic analysis of a downhole processing plant (DPP) using a horizontally installed water/oil separator has been performed. The Improved Oil Recovery (IOR)part has been analysed with a relevant flow simulation tool. Based on the given reservoir depth/pressure, flow rate, viscosity/density and water cut, the simulations show that a significant improved production rate/income can be achieved by extracting the produced water downhole and performing re-injection into the producing reservoir to maintain reservoir pressure. In addition, the expected lifetime of the well is increased by several years. The conclusion is that the earlier the separator is installed, the greater the total well income. In addition, details regarding not only multi-lateral wells through level 5 junctions but also production string with separator and valve system has been evaluated and is concluded to be feasible for the well in question The removal of water downhole has several advantages, for example the removal of the water column up to the surface will reduce the reservoir back pressure and will improve recovery /production rates. In addition, not lifting the water will reduce energy consumption/CO2 footprint, and removal of water will reduce surface processing and possible re-injection and chemical treatment cost. In general, water separation downhole is advantageous, due to the higher pressure.

scholarly journals Development of Proxy Models for Screening Water Flood and Gas Flood Candidates

2021 ◽  
pp. 51-57
Author(s):  
Moyosore, Olanipekun ◽  
Akpabio, Julius U. ◽  
Isehunwa, Sunday O.
Keyword(s):  
Oil Recovery ◽  
Gas Injection ◽  
Water Injection ◽  
Screening Method ◽  
Water Flooding ◽  
Improved Oil Recovery ◽  
Screening Criteria ◽  
Recovery Techniques ◽  
Oil Formation Volume Factor ◽  
Proxy Models

Fluid-flood and other improved oil recovery techniques are becoming prominent in global petroleum production because a large proportion of production is from mature oil fields. Although water flooding and gas injection are well established techniques in the industry, several of the screening criteria in literature are discipline which could sometimes be subjective. This work used experimental design techniques to develop proxy models for predicting oil recovery under water-flood and gas-flood conditions. The objective of the study is to develop a quantitative screening method that would allow for candidates to be evaluated and ranked for water flood or gas injection. The model was applied to some field cases and compared with published models and the well-known Welge Analysis method. The coefficient constants for the oil formation volume factor for water flooding and gas injection was 0.0139 and 0.0434 respectively. Similarly, the coefficient constants for water injection and gas injection for the generated proxy model was -2.34* 10-8 and -6.1 *10-5 respectively. The results show that the proxy models developed are quite robust and can be used for first pass screening of water and gas flood candidates. 

RESERVOIR SIMULATION IN THE MEREENIE FIELD

1986 ◽  
Vol 26 (1) ◽  
pp. 428
Author(s):  
B.F. Towler
Keyword(s):  
Oil Recovery ◽  
Reservoir Simulation ◽  
Water Injection ◽  
Gas Oil ◽  
The North ◽  
Stock Tank ◽  
Bottom Hole Flowing Pressure ◽  
Steep Decline ◽  
Oil Rim ◽  
Reservoir Simulator

The Mereenie Field in the Amadeus Basin was discovered in 1964 and contains an estimated 240 million barrels of oil and 480 billion (USA) cubic feet of gas in three formations. The field commenced production at 1500 barrels of oil per day from seven wells in September 1984. The structure is large and elongated and the oil in the permeable sands appears as a rim round the structure. This paper describes a reservoir simulation study initiated to evaluate the recovery of oil from wells sited on the north and south flanks of the anticline where the steep dips cause the oil rim to become very narrow.Ten studies were made on a 21 × 15 cell pattern model using a three phase semi-implicit black oil reservoir simulator. The ten runs compared oil recovery and gas/oil ratio as a function of formation dip, bottom hole flowing pressure, gas injection and water injection. These showed that the flank wells could be expected to recover 300 000 stock tank barrels of oil from primary and secondary operations which represents about 25 per cent of the oil in place for wells sited on half mile spacings. However the wells will experience high gas/oil ratios and a steep decline in oil rate.

Synergy of Polymer for Mobility Control and Surfactant for Interface Elasticity Increase in Improved Oil Recovery

2021 ◽  
Author(s):  
Taniya Kar ◽  
Abbas Firoozabadi
Keyword(s):  
Oil Recovery ◽  
Sea Water ◽  
Synergistic Effects ◽  
Water Injection ◽  
Mobility Control ◽  
Residual Oil ◽  
Sweep Efficiency ◽  
Improved Oil Recovery ◽  
Low Salinity ◽  
Low Salinity Waterflooding

Abstract Improved oil recovery in carbonate rocks through modified injection brine has been investigated extensively in recent years. Examples include low salinity waterflooding and surfactant injection for the purpose of residual oil reduction. Polymer addition to injection water for improvement of sweep efficiency enjoys field success. The effect of low salinity waterflooding is often marginal and it may even decrease recovery compared to seawater flooding. Polymer and surfactant injection are often effective (except at very high salinities and temperatures) but concentrations in the range of 5000 to 10000 ppm may make the processes expensive. We have recently suggested the idea of ultra-low concentration of surfactants at 100 ppm to decrease residual oil saturation from increased brine-oil interfacial elasticity. In this work, we investigate the synergistic effects of polymer injection for sweep efficiency and the surfactant for interfacial elasticity modification. The combined formulation achieves both sweep efficiency and residual oil reduction. A series of coreflood tests is performed on a carbonate rock using three crude oils and various injection brines: seawater and formation water with added surfactant and polymer. Both the surfactant and polymer are found to improve recovery at breakthrough via increase in oil-brine interfacial elasticity and injection brine viscosification, respectively. The synergy of surfactant and polymer mixed with seawater leads to higher viscosity and higher oil recovery. The overall oil recovery is found to be a strong function of oil-brine interfacial viscoelasticity with and without the surfactant and polymer in sea water and connate water injection.

A Microvisual Study of the Displacement of Viscous Oil by Polymer Solutions

2011 ◽  
Vol 14 (03) ◽  
pp. 269-280 ◽  
Author(s):  
M.. Buchgraber ◽  
T.. Clemens ◽  
L. M. Castanier ◽  
A. R. Kovscek
Keyword(s):  
Polymer Solution ◽  
Oil Recovery ◽  
Polymer Solutions ◽  
Pore Space ◽  
Polymer Concentration ◽  
Water Injection ◽  
Sweep Efficiency ◽  
Improved Oil Recovery ◽  
Associative Polymers ◽  
Displacement Front

Summary Of the various enhanced-oil-recovery (EOR) polymer formulations, newly developed associative polymers show special promise. We investigate pore and pore-network scales because polymer solutions ultimately flow through the pore space of rock to displace oil. We conduct and monitor optically water/oil and polymer-solution/oil displacements in a 2D etched-silicon micromodel. The micromodel has the geometrical and topological characteristics of sandstone. Conventional hydrolyzed-polyacrylamide solutions and newly developed associative-polymer solutions with concentrations ranging from 500 to 2,500 ppm were tested. The crude oil had a viscosity of 450 cp at test conditions. Our results provide new insight regarding the ability of polymer to stabilize multiphase flow. At zero and low polymer concentrations, relatively long and wide fingers of injectant developed, leading to early water break-through and low recoveries. At increased polymer concentration, a much greater number of relatively fine fingers formed. The width-to-length ratio of these fingers was quite small, and the absolute length of fingers decreased. At a larger scale of observation, the displacement front appears to be stabilized; hence, recovery efficiency improved remarkably. Above a concentration of 1,500 ppm, plugging of the micromodel by polymer and lower oil recovery was observed for both polymer types. For tertiary polymer injection that begins at breakthrough of water, the severe fingers resulting from water injection are modified significantly. Fingers become wider and grow in the direction normal to flow as polymer solution replaces water. Apparently, improved sweep efficiency of viscous oils is possible (at this scale of investigation) even after waterflooding. The associative- and conventional-polymer solutions improved oil recovery by approximately the same amount. The associative polymers, however, showed more-stable displacement fronts in comparison to conventional-polymer solutions.

Water Injection, Polymer Injection and Polymer Alternating Water Injection for Enhanced Oil Recovery: A Laboratory Study

2013 ◽  
Author(s):  
Marcelo F. Zampieri ◽  
Rosangela B. Z. L. Moreno
Keyword(s):  
Oil Recovery ◽  
Produced Water ◽  
Water Injection ◽  
Mobility Ratio ◽  
Sweep Efficiency ◽  
Polymer Injection ◽  
Paraffin Oil ◽  
Water Viscosity ◽  
Water Volumes ◽  
Expensive Process

Developing an efficient methodology for oil recovery is extremely important in this commodity industry, which may indeed lead to wide spread profitability. In the conventional water injection method, oil displacement occurs by mechanical behavior between fluids. Nevertheless, depending on mobility ratio, a huge quantity of injected water is necessary. Polymer injection aims to increase water viscosity and improve the water/oil mobility ratio, thus improving sweep efficiency. The alternating banks of polymer and water injection appear as an option for the suitable fields. By doing so, the bank serves as an economic alternative, as injecting polymer solution is an expensive process. The main objective of this study is to analyze and comparison of the efficiency of water injection, polymer injection and polymer alternate water injection. For this purpose, tests were carried out offset in core samples of sandstones using paraffin oil, saline solution and polymer and were obtained the recovery factor and water-oil ratio for each method. The obtained results for the continuous polymer injection and alternating polymer and water injection were promising in relation to the conventional water injection, aiming to anticipate the oil production and to improve the water management with the reduction of injected and produced water volumes.

scholarly journals Evaluation of Polymer Flooding in a Highly Stratified Heterogeneous Reservoir. A Field Case Study

2020 ◽  
Vol 16 ◽  
Keyword(s):  
Oil Recovery ◽  
History Matching ◽  
Lower Layer ◽  
Polymer Flooding ◽  
Economic Life ◽  
Water Flooding ◽  
Base Case ◽  
Sweep Efficiency ◽  
Sector Model ◽  
Reservoir Simulator

Oil and gas companies are looking for proven hydrocarbon reserves from their mature drained reservoirs to extend the production and economic life of these fields. The chemical enhanced oil recovery (CEOR) is an attractive water-based EOR method for these mature fields. The polymer flooding (PF) is a widely applied process in reservoirs with low sweep efficiency after the water flooding (WF). The target Colombian field has one of the first polymer pilots in the region with positive results of oil recovery in “A” sands. Thus, the operator is interested in the expansion of PF for the same reservoir and even in deeper reservoir sands. This paper focuses in the evaluation of different scenarios of PF for the producer in layers A and B with a mechanistic simulation model, thus obtaining new recommendations for the recovery strategy in the field. A sector model was constructed from a full field model using a commercial reservoir simulator to the in-house chemical flooding reservoir simulator: UTCHEMRS. This sector model was also migrated to a second commercial simulator allowing a performance comparison for these three simulators. UTCHEMRS model results were compared with the commercial simulators through the history matching (HM) phase. The primary and waterflood history match was in agreement with the field data. Simulation results suggested that PF for the base case in “A” sands presented an incremental oil recovery of up to 12% additional to water flooding. Additionally, PF was extended to the lower layer “B” sand to investigate the potential of polymer injection. The PF injection in both reservoirs simultaneously loses sweep efficiency and decreases the oil recovery to about 3%. However, a hypothetical case of new infill producer wells with the objective of testing the individual reservoir performance has revealed that PF is having significant upside from B sands as well.

60 Years Field Performance Data-Driven Analytics to Generate Updated Waterflood Field Development Plan in a North Kuwait Giant Carbonate Reservoir

2021 ◽  
Author(s):  
Basel AL-Otaibi ◽  
Issa Abu Shiekah ◽  
Manish Kumar Jha ◽  
Gerbert de Bruijn ◽  
Peter Male ◽  
...  
Keyword(s):  
Oil Recovery ◽  
Water Injection ◽  
Oil Production ◽  
Horizontal Wells ◽  
Carbonate Reservoir ◽  
Development Plan ◽  
Data Driven ◽  
Water Flooding ◽  
Field Development ◽  
The Impact

Abstract After 40 years of depletion drive, a mature, giant and multi-layer carbonate reservoir is developed through waterflooding. Oil production, sustained through infill drilling and new development patterns, is often associated with increasingly higher water production compared to earlier development phases. A field re-development plan has been established to alleviate the impact of reservoir heterogeneities on oil recovery, driven by the analysis of the historical performance of production and injection of a range of well types. The field is developed through historical opportunistic development concepts utilizing evolving technology trends. Therefore, the field has initially wide spacing vertical waterflooding patterns followed by horizontal wells, subjected to seawater or produced water injection, applying a range of wells placement or completion technologies and different water injection operating strategies. Systematic categorization, grouping and analyzing of a rich data set of wells performance have been complemented and integrated with insights from coarse full field and conceptual sector dynamic modeling activities. This workflow efficiently paved the way to optimize the field development aiming for increased oil recovery and cost saving opportunities. Integrated analysis of evolving historical development decisions revealed and ranked the primary subsurface and operational drivers behind the limited sweep efficiency and increased watercut. This helped mapping the impact of fundamental subsurface attributes from well placement, completion, or water injection strategies. Excellent vertical wells performance during the primary depletion and the early stage of water flooding was slowly outperformed by a more sustainable horizontal well production and injection strategy. This is consistent with a conceptual model in which the reservoir is dominated by extensive high conductive features that contributed in the early life of the field to good oil production before becoming the primary source of premature water breakthrough after a limited fraction of pore volume water was injected. The next level of analysis provided actual field evidence to support informed decisions to optimize the front runner horizontal wells development concept to cover wells length, orientation, vertical placement in the stratigraphy, spacing, pattern strategy and completion design. The findings enabled delivering updated field development plan covering the field life cycle to sustain and increase field oil production through adding ~ 200 additional wells and introducing more structured water flooding patterns in addition to establishing improved wells reservoir management practices. This integrated study manifests the power, efficiency and value from data driven analysis to capture lessons learned from evolving wells and development concepts applied in a complex brown field over six decades. The workflow enabled the delivery of an updated field development plan and production forecasts within a year through utilizing data analytics to compensate for the recognized limitations of subsurface models in addition to providing input to steer the more time-consuming modeling activities.

Sign in / Sign up

Export Citation Format

Share Document