The Effect of Bottom Water Coning and Its Monitoring for Optimization in SAGD

Masih, Shahbaz; Ma, K.; Sanchez, Julio; Patino, Fabian; Boida, Lindsey

doi:10.2118/157797-ms

Cited by 16 publications

(9 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Relative permeability relationships of oil/water and gas/liquid systems for the clean sand and low-quality sand (LQS) are adopted from Mohebati et al (2010), as shown in Fig. 3.…”

Section: Multiphase-flow Functions (Relative Permeability and Capillamentioning

confidence: 99%

“…Those difficulties with experimental analysis can be partially overcome with numerical simulation, which was widely used to monitor the advancement of steam chambers (Lerat et al 2010;Leskiw and Gates 2012) and to optimize operational strategies (Zhao et al 2007;Mohebati et al 2010;Nguyen et al 2012). Law et al (2003) investigated field-scale SAGD performance in the presence of confined and unconfined top water.…”

Section: Introductionmentioning

confidence: 99%

“…Their results suggest that increasing the pressure difference between the steam chamber and the top-water zone would lead to unfavorable SAGD performance. In reservoirs with underlying bottomwater (Masih et al 2012), the performance of SAGD depends on the vertical offset and pressure differential between the producer and the water zone. Ricardo (2013) confirmed through numerical simulations that the negative impacts of bottomwater increase with its thickness; a vertical offset of 5 m was determined to be the optimum in terms of project economics.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Characterizing the Effects of Lean Zones and Shale Distribution in Steam-Assisted-Gravity-Drainage Recovery Performance

Wang

Leung

2015

SPE Reservoir Evaluation &Amp; Engineering

View full text Add to dashboard Cite

Performance of steam-assisted gravity drainage (SAGD) is influenced significantly by the distributions of lean zones and shale barriers, which tend to impede the vertical growth and lateral spread of a steam chamber. Previous literature has partially addressed their effects on SAGD performance; however, a comprehensive and systematic investigation of the heterogeneous distribution (location, continuity, size, saturation, and proportions) of shale barriers and lean zones is still lacking.In this study, numerical simulations are used to model the SAGD process. Capillarity and relative permeability effects, which were ignored in many previous simulation studies, are incorporated to model bypassed oil. Numerous ranking schemes are formulated to analyze various aspects of SAGD performance. A detailed sensitivity analysis is performed by varying the location, continuity, size, proportions, and saturation of these heterogeneous features. Lean zones and shale lenses (imbedded in a region of degraded rock properties) with different sizes and degrees of continuity are placed in areas above the injector, below the producer, or in between the well pair. It is noted that among numerous parameters that influence the ultimate recovery, remaining bypassed oil, chamber advancement, and heat loss, continuity and position of these features in relation to the well pair play a particularly crucial role. Neural network modeling is subsequently used for constructing data-driven models to identify and propose a set of input variables for correlating relevant parameters or measures, which are descriptive of the heterogeneity and properties of the shale barriers and lean zones, to recovery and ranking results.This work provides a guideline for assessing the impacts of reservoir and saturation heterogeneities on SAGD performance. A set of input variables and parameters that have significant impacts on the ensuing recovery response is identified. One can define readily the proposed set of variables from well logs and apply immediately in data-driven models with field data and scaleup analysis of experimental models to assist field-operation design and evaluation. One can also extend the approach presented in this paper to analyze other solvent-assisted SAGD processes.

show abstract

“…Relative permeability relationships of oil/water and gas/liquid systems for the clean sand and low-quality sand (LQS) are adopted from Mohebati et al (2010), as shown in Fig. 3.…”

Section: Multiphase-flow Functions (Relative Permeability and Capillamentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Characterizing the Effects of Lean Zones and Shale Distribution in Steam-Assisted-Gravity-Drainage Recovery Performance

Wang

Leung

2015

SPE Reservoir Evaluation &Amp; Engineering

View full text Add to dashboard Cite

show abstract

“…To find its volume, the steam condensate volume must be known and subtracted from the total water production. However, even a very comprehensive monitoring of temperature and pressure cannot provide a reasonable estimate of steam condensation (Masih et al 2012). In this study, volume of steam condensate production is estimated using material balance at steady-state condition.…”

Section: Concept Assumptions and Approachmentioning

confidence: 99%

Improved Thermal Heavy Oil Recovery from Strong Bottom-Water-Drive Reservoir by Combining SAGD with Downhole Water Sink

Qin

Wojtanowicz

Li³

2014

Day 1 Mon, December 08, 2014

View full text Add to dashboard Cite

While SAGD (Steam Assisted Gravity Drainage) can be used to recovery heavy oil from strong bottom water drive reservoir, the bottom water is known to have a detrimental effect on the SAGD performance, may cause unsuccessful SAGD application. During SAGD process, the common practice to control the water encroachment is to keep the steam chamber pressure at or above the aquifer pressure. At higher pressure, less latent heat is available, leading to unprofitable SAGD project with low oil production rate and low oil recovery.In this paper, an innovative approach is proposed to tackle the problem by combining the use of SAGD with DWS (Downhole Water Sink). The concept of DWS is the first to be integrated into SAGD production process. With a new type of well completion design, along with the two separated wells of SAGD, another well is completed in the water zone to decrease the aquifer pressure through continuous water production. As the aquifer pressure decreasing, low steam chest pressure can be maintained, thus allowing for more latent heat available in the formation which would ensure high oil rate and high oil recovery.A theoretical study of SAGD-DWS performance on improving heavy oil recovery is conducted in this paper. A design model is developed to predict the optimum ranges of the SAGD-DWS production parameters under various operation scenario. The effects of the new approach on increasing oil rate and improving oil recovery in comparison to that of conventional SAGD are quantified. The results demonstrate that unlike other thermal recovery methods, the combined use of SAGD with DWS can prevent the water invasion into the steam chamber while allowing for low steam chamber pressure with high heat efficiency.

show abstract

“…For the startup phase of SAGD process, there are three approaches, including cyclic steam stimulation, steam circulation and fracturing. The factors to influence the development results of SAGD process included the following aspects [16][17][18][19]. (1) Reservoir thickness.…”

Section: Introductionmentioning

confidence: 99%

Feasibility of the Steam-Assisted-Gravity-Drainage Process in Offshore Heavy Oil Reservoirs with Bottom Water

et al. 2014

View full text Add to dashboard Cite

Due to the water-coning problem, cycle steam stimulation (CSS) in the heavy oil reservoirs with bottom water is often less effective, and the oil recovery is even below 10%. Steam assisted gravity drainage (SAGD) is the oil-producing process with a constant pressure-drop (about 0.30 MPa), and it is a potential technique for this reservoirs. Through the implementation of SAGD, bottom water could be effectively controlled. Aiming at the LD heavy oil block in Bohai offshore oilfield, the SAGD performance in heterogeneous heavy oil reservoir with bottom water was numerically studied in this paper. In these simulation models, the water was broken into three components (connate water, injected water and bottom water) to study the water producing in SAGD process. Thus, the influences of startup approach, oillayer thickness, water thickness and the distance between well-pair and bottom-water on the water rising were all simulated. Thereafter, a set of numerical simulations were performed to assess the shale issues in SAGD process, e.g. the vertical and horizontal position of shalebarriers, the shale distribution range, the barrier permeable condition and the macroscopic vertical permeability.Results indicated that bottom water reduced the ultimate recovery of SAGD process by about 10% of the OOIP. The startup by steam-circulation was much suitable for the bottom water heavy oil reservoir instead of CSS approach. The bottom water tremendously reduced the startup pressure-decline rate, and thus the startup-time was prolonged. The distance between well pair and water zone had a great influence on the SAGD performance, and a small distance would delay the beginning time of the steam-chamber rising. For reservoir heterogeneity, the vertical and horizontal heterogeneity have great influence on the drainage process, especially the shale cases. It tremendously decreased the recovery rate by about one time. This investigation could be used as a tool for the successful design of SAGD process in heavy oil reservoirs with bottom water.

show abstract

The Effect of Bottom Water Coning and Its Monitoring for Optimization in SAGD

Cited by 16 publications

References 4 publications

Characterizing the Effects of Lean Zones and Shale Distribution in Steam-Assisted-Gravity-Drainage Recovery Performance

Characterizing the Effects of Lean Zones and Shale Distribution in Steam-Assisted-Gravity-Drainage Recovery Performance

Improved Thermal Heavy Oil Recovery from Strong Bottom-Water-Drive Reservoir by Combining SAGD with Downhole Water Sink

Feasibility of the Steam-Assisted-Gravity-Drainage Process in Offshore Heavy Oil Reservoirs with Bottom Water

Contact Info

Product

Resources

About