The paper discusses the feasibility study approach of polymer flooding enhanced oil recovery. This work is focused on understanding and quantifying key aspects of polymer flooding and design parameter optimization case. A synthetic reservoir simulation model was employed for the study.
The first stage is to identify and understand key factors that have most significant impact to polymer flooding response. There are eight parameters that are considered in the analysis, such as polymer concentration, polymer thermal degradation, polymer injection duration, and polymer-rock properties (adsorption, residual resistance factor, etc.). The impact of each parameter to oil recovery response was sensitized with its low, mid, and high values. The difference of high to low oil recovery output for all parameters was ranked to determine their significance levels. The top three parameters obtained from the sensitivity analysis are polymer injection duration, thermal degradation, and polymer concentration. Sensitivity cases of polymer injectivity and thermal degradation effects were covered in this work.
The second stage is to determine optimum design parameters of polymer flooding. The most significant parameters from the sensitivity analysis results were considered for further optimization. Three parameters that were selected for design optimization include polymer injection duration, polymer concentration, and well spacing. An optimization workflow with simplex algorithm is linked with a reservoir simulator to generate optimization cases by varying values of optimized parameters. The optimization iteration stops when the maximum value of the objective function, which is the net revenue, is reached. The optimization cycle was done for rock permeability of 500 md and 1000 md.
For a low rock permeability reservoir, the well spacing should be short and a lower polymer concentration is sufficient to provide a good response, in addition to avoiding potential injectivity problem. There should be minimum injectivity problem for reservoir with permeability above 1000 md. It is very important to apply polymer thermal degradation in the simulation model to avoid an optimistic performance prediction. The sensitivity analysis results provide a good understanding on the significance impact of parameters controlling polymer injection response and potential challenges. The optimization approach used in the study aids in investigating many optimization scenario within a short period of time.
ExxonMobil’s hot streak of offshore discoveries have sparked investor interest in the Guyana-Suriname basin. How did the company get there, and why do industry representatives feel optimistic about future deepwater prospects in the region? In the 30 years of operations on Suriname’s Tambaredjo field, the prime mechanism for lifting the 15.6 °API crude to surface has been that of progressing cavity pumps (PCPs).
The second round will offer 19 offshore blocks clustered in five zones to continue natural gas development in the eastern Mediterranean’s Levant Basin. Devon Energy will be getting simpler and smaller by selling two no-growth assets—gas acreage in the Barnett Shale in Texas and oil sand operations in Canada. Its future is staked on growing oil production in the Permian’s Delaware Basin and three other unconventional oil plays. The Oklahoma City independent has a new-look portfolio and new operational and financial priorities. And now it has enlisted an energy research firm to leverage advanced analytics and machine learning to help get the most out of its assets.
The Pluma-1 discovery could turn the southeast portion of Stabroek Block off Guyana "into a major new development area," the company says. Odds on the World vs. Permian Fight Are Narrowing While US onshore still holds an edge, international oil companies are finding attractive options for diversifying their portfolios, mixing onshore with offshore conventional fields, where finding and development costs are down, and the time it takes to bring them on line. Already poised to produce more than 500,000 B/D offshore Guyana, ExxonMobil added yet another discovery to its bounty in the emerging regional oil powerhouse, meaning a fourth development phase could be in order. ExxonMobil’s hot streak of offshore discoveries have sparked investor interest in the Guyana-Suriname basin. How did the company get there, and why do industry representatives feel optimistic about future deepwater prospects in the region?
Petrobras and Shell have brought online the Lula field’s seventh FPSO as the firms continue to ramp up production from the pre-salt Santos Basin. The French major is racking up barrels of deepwater production as part of its large-scale West African push. This paper describes how a technique known as applied-surface-backpressure managed-pressure drilling (ASBP-MPD) can alleviate the limitations of conventional deepwater well control. Majors BP and Chevron have overcome development challenges and delays to launch their respective Clair Ridge and Big Foot projects. The unit is flowing oil and gas from the Lula Extremo Sul area, 290 km off Rio de Janeiro state in 2150 m of water.
The US majors plan to produce around 1 million BOE/D each from the basin, which has become a primary focus of their upstream operations. An assortment of sustainability initiatives shows how the oil and gas industry, leveraging its reach, diversity, and resources, is going well beyond just supplying energy to impact the world for the better. The discovery is world’s third-largest natural gas discovery in the past 2 years. Exxon Mobil is reorganizing and creating three new upstream companies and a global projects company. Natural gas prices have risen in the US but not in west Texas.
Funding for startups in the upstream industry does not always guarantee that oil and gas companies will want to test the new technology. A new venture and accelerator model hopes to change this through guaranteed pilots. The Pluma-1 discovery could turn the southeast portion of Stabroek Block off Guyana "into a major new development area," the company says. ExxonMobil and Hess led the way in the most active regionwide US gulf lease sale thus far. Operators are working with a young startup company to overhaul how the unconventional sector has traditionally interpreted one the most common tests used to influence well completion designs.
Siv Marie Åsen, UiS, IRIS, and The National IOR Centre of Norway; Arne Stavland and Daniel Strand, IRIS; and Aksel Hiorth, UiS, IRIS, and The National IOR Centre of Norway Summary In this work, we examine the common understanding that mechanical degradation of polymers takes place at the rock surface or within the first few millimeters of the rock. The effect of core length on mechanical degradation of synthetic enhanced-oil-recovery (EOR) polymers was investigated. We constructed a novel experimental setup for studying mechanical degradation at different flow velocities as a function of distances traveled. The setup enabled us to evaluate degradation in serial mounted core segments of 3, 5, 8, and 13 cm individually or combined. By recycling, we could also evaluate degradation at effective distances up to 20 m. Experiments were performed with two different polymers [high-molecular-weight (MW) hydrolyzed polyacrylamide (HPAM) and low-MW acrylamide tertiary butyl sulfonic acid (ATBS)] in two different brines [0.5% NaCl and synthetic seawater (SSW)]. In the linear flow at high shear rates, we observed a decline in degradation rate with distance traveled. Even after 20 m, some degradation occurred. However, the observed degradation was associated with high pressure gradients of 100 bar/m, which at field scale is not realistic. It is possible that oxidative degradation played a significant role during our experiments, where the polymer was cycled many times through a core.
A bulk of near-term output will come domestically, but the subsidiary of state-owned China National Offshore Oil Corporation is leaning on its international projects to boost production longer-term. The company said it expects to produce 1.33 million BOE/D in 2019, an increase of 2% from its 2018 average, with domestic output accounting for 67% of this year’s production. The ExxonMobil-operated Guyana consortium has tallied 10 discoveries to date. CNOOC expects six new projects to come on stream this year. The four other projects are the Shell-operated Appomattox project in the US gulf and CNOOC’s Bozhong 34-9 oil field, Caofeidian 11-1/11-6 comprehensive adjustment project, and Wenchang 13-2 comprehensive adjustment project off China.
In the fluid flow study of polymer solutions through porous media in chemical enhanced oil recovery (ChemEOR) it is important to take into account very important properties such as the adsorption of polymer on mineral substrates, the residual resistance factor (Rk), the resistance factor (Rm), the wettability of the medium and cumulative recovery factor. For these reasons, this study has as main objective to evaluate rock-fluid behavior in presence of polymeric formulations by coreflood tests in porous media representative of extra-heavy crude reservoir conditions. To do this, an experimental methodology was proposed and a range of concentrations (800, 1500 and 2000 ppm) was established as the main variable of this study. Subsequently, relative permeability curves (Kr) on real sand cores were generated with an average absolute permeability of 7486.60 mD. Resulting in endpoints of the area of interest of: 29.0% and 65.6% of Swirr (Irreducible water saturation) and Sor (Residual oil saturation) respectively and a primary recovery factor of 36.4%. The amount of polymer adsorbed under dynamic regime was 19.1, 124.1 and 136.9 ug polymer/g rock. Following the same order, the values of additional oil recovery factor under polymer injection were 5.4, 10.2 and 15.2%, indicating a proportional increase with respect to injected concentration. However, there was no apparent correlation between the polymer concentration and residual resistance factor. Additionally, the initial wettability of the medium was preferential to water and this property increased with the injection of polymer formulations. Finally, using a methodology developed in this study, recycled polymer produced efficient results in ChemEOR processes generating an additional recovery factor of 2.38%. It also reduced the mobility of water in 98% (of that reported initially) and lastly its injection proportion per volume of crude produced was 3.522.