Computational Studies of Two-Phase Cement/CO2/Brine Interaction in Wellbore Environments

Summary Wellbore integrity is essential to ensuring long-term isolation of buoyant supercritical carbon dioxide (CO2) during geologic sequestration of CO2. In this paper, we summarize recent progress in numerical simulations of cement/brine/CO2 interactions with respect to migration of CO2 outside of casing. Using typical values for the hydrologic properties of cement, caprock (shale), and reservoir materials, we show that the capillary properties of good-quality cement will prevent flow of CO2 into and through cement. Rather, CO2, if present, is likely to be confined to the casing/cement or cement/formation interface. CO2 does react with the cement by diffusion from the interface into the cement, in which case it produces distinct carbonation fronts within the cement. This is consistent with observations of cement performance at the CO2-enhanced-oil-recovery Scurry Area Canyon Reef Operators Committee (SACROC) unit in west Texas (Carey et al. 2007). For poor-quality cement, flow through cement may occur and would produce a pattern of uniform carbonation without reaction fronts. We also consider an alternative explanation for cement carbonation reactions as caused by CO2 derived from caprock. We show that carbonation reactions in cement are limited to surficial reactions when CO2 pressure is low (< 10 bar), as might be expected in many caprock environments. For the case of caprock overlying natural CO2 reservoirs for millions of years, we consider the Scherer and Huet (2009) hypothesis of diffusive steady state between CO2 in the reservoir and in the caprock. We find that, in this case, the aqueous CO2 concentration would differ little from that in the reservoir and would be expected to produce carbonation reaction fronts in cements that are relatively uniform as a function of depth.

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Effect of Graphene Nanoplatelet on the Carbonation Depth of Concrete under Changing Climate Conditions

Applied Sciences ◽

10.3390/app11199265 ◽

2021 ◽

Vol 11 (19) ◽

pp. 9265

Author(s):

Yingzi Zhang ◽

Yanze Wang ◽

Mingqian Yang ◽

Huatao Wang ◽

Guofang Chen ◽

...

Keyword(s):

Control Sample ◽

Co2 Concentration ◽

Favorable Effect ◽

Carbonation Depth ◽

Graphene Nanoplatelet ◽

Carbonation Reaction ◽

Climate Conditions ◽

Ordinary Concrete ◽

Changing Climate ◽

Carbon Dioxide Co2

Climate change has been unprecedented in the past decades or even thousands of years, which has had an adverse impact on the mechanical properties of concrete structures. Many researchers have begun to study new concrete materials. Graphene nanoplatelet (GNP) is an attractive nanomaterial that can change the crystal structure of concrete and improve durability. The aim of the present study was to investigate the effect of GNP (0.05%wt) on the carbonation depth of concrete under simulated changing climate conditions (varying temperature, relative humidity, and carbon dioxide (CO2) concentration), and compare it with ordinary concrete. When the concentration of CO2 is variable, the carbonation depth of graphene concrete is 10% to 20% lower than that of ordinary concrete. When the temperature is lower than 33 °C, the carbonation depth of graphene concrete is less than that of the control sample; however, above 33 °C, the thermal conductivity of GNP increases the carbonation reaction rate of concrete. When the humidity is a variable, the carbonation depth of graphene concrete is less than 15% to 30% of ordinary concrete, and when the humidity is higher than 78%, the difference in the carbonation depth between the ordinary concrete and the graphene concrete decreases gradually. The overall results indicated that GNP has a favorable effect on anti-carbonation performance under changing climate conditions.

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Disk/Cavity Wall Cooling Effectiveness Experiments With Air and CO2 as Coolants

Volume 1: Turbomachinery ◽

10.1115/94-gt-068 ◽

1994 ◽

Author(s):

B. V. Johnson ◽

W. A. Daniels

Keyword(s):

Large Scale ◽

Space Shuttle ◽

Co2 Concentration ◽

Scale Model ◽

Large Scale Model ◽

Rotor Wall ◽

Flow Through ◽

Carbon Dioxide Co2 ◽

Momentum Integral ◽

Main Engine

Experiments were conducted with a turbopump drive disk/cavity model to determine the effects of coolant density on the composition of the fluid within a disk cavity. The 3-D, large-scale model simulated the aft cavity of the Space Shuttle Main Engine (SSME) high-pressure-fuel turbopump including the flow through the blade shanks of the second stage turbine and the nuts and bolts on the rotor and cavity walls. Coolant was injected near the bore of the turbine disk and gas sampling measurements were made to determine the fraction of the gas from each fluid source. Air was used as the gas entering the cavity through the blade shanks and air or carbon dioxide (CO2) was used as the coolant injected axisymetrically near the rotor bore. CO2 was also used as a trace gas when air was used as the simulated coolant. All the flow exited the cavity through the rim seal. CO2 concentration measurements were made to deterime the composition of gas withdrawn through pressure taps at selected radii from the disk bore to the simulated airfoil platforms. Results were obtained and are presented for a range of coolant flow rates. When air was used as coolant, the rotor wall concentrations were approximately 100 percent coolant from the disk bore to radii where momentum integral models indicate all the coolant is entrained in the disk boundary layers. When the coolant was CO2, having a density of approximately 1.5 times that of air, the coolant concentrations were generally less on both the rotor and cavity walls, indicating that the higher density coolant produced increased mixing with the upstream flow, entering near the cavity OD through the blade shanks.

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ANALYTICAL SOLUTION OF TWO-PHASE INCOMPRESSIBLE FLOW EQUATION IN A HOMOGENEOUS POROUS MEDIUM

INTERNATIONAL JOURNAL OF MATHEMATICS AND COMPUTER RESEARCH ◽

10.47191/ijmcr/v9i7.03 ◽

2021 ◽

Vol 9 (7) ◽

Author(s):

Zuonaki vaOngodiebi ◽

Keyword(s):

Porous Medium ◽

Analytical Solution ◽

Oil Recovery ◽

Incompressible Flow ◽

Flow Equation ◽

Pressure Variation ◽

Two Phase ◽

Depth Profiles ◽

Homogeneous Porous Medium ◽

Flow Through

In this research, we present analytical solution of two phase incompressible flow through a homogeneous porous medium. Water was injected at one end of the porous medium to stimulate oil recovery at the other end. From the modelled equations, we are able to determine pressure variation at different depth profiles. The results revealed increase in pressure as depth increases. This is in line with what is obtainable in practical scenarios.

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Simple and Robust Algorithm for Multiphase Equilibrium Computations at Temperature and Volume Specifications

SPE Journal ◽

10.2118/205499-pa ◽

2021 ◽

pp. 1-20

Author(s):

Chang Lu ◽

Zhehui Jin ◽

Huazhou Li ◽

Lingfei Xu

Keyword(s):

Oil Recovery ◽

Trust Region Method ◽

Trust Region ◽

Co2 Injection ◽

Effective Equation ◽

Two Phase ◽

Robust Algorithm ◽

Equation Solving ◽

Carbon Dioxide Co2 ◽

Nested Approach

Summary Two-phase and three-phase equilibria are frequently encountered in a variety of industrial processes, such as carbon dioxide (CO2) injection for enhanced oil recovery in oil reservoirs, multiphase separation in surface separators, and multiphase flow in wellbores and pipelines. Simulation and engineering design of these processes using isothermal/isochoric (VT) multiphase equilibrium algorithms are sometimes more convenient than that using the conventional isothermal/isobaric (PT) algorithms. This work develops a robust algorithm for VT multiphase equilibrium calculations using a nested approach. The proposed algorithm is simple because a robust PT multiphase equilibrium algorithm is used in the inner loop without any further modifications, while an effective equation-solving method (i.e., Brent’s method; Brent 1971) is applied in the outer loop to solve the pressure corresponding to a given volume/temperature specification. The robustness of the VT algorithm is safeguarded by using a highly efficient trust-region-method-based PT algorithm. We demonstrate the good performance of the newly developed algorithm by applying it to calculate the isochores of fluid mixtures that exhibit both two-phase and three-phaseequilibria.

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Evaluating the Effects of CO2 Injection in Faulted Oil Reservoirs

10.2118/spe-169933-ms ◽

2014 ◽

Author(s):

A.. Augustus ◽

D.. Alexander

Keyword(s):

Carbon Dioxide ◽

Oil Recovery ◽

Injection Rate ◽

Oil Reservoirs ◽

Co2 Injection ◽

Geologic Sequestration ◽

Sweep Efficiency ◽

Fracture Pressure ◽

Carbon Dioxide Co2 ◽

Migration Pathways

Abstract The geologic sequestration of carbon dioxide (GCS) into depleted reservoirs has been contemplated and tested in several projects globally both for permanent storage of carbon dioxide (CO2) and enhancing oil recovery (EOR). Utilization of geologic sequestration as a mitigation strategy to reduce the effects of anthropogenic CO2 into the atmosphere may be costly without proper incentives. This cost can be lowered when incremental oil is recovered in mature fields because of rising oil prices and possibly earning carbon credits for sequestered CO2. The injection of CO2, for most of the infrastructure should be in place for mature fields. Therefore many EOR coupled with CO2 sequestration projects attempt to maximize the recovery of oil whilst storing as much CO2 as possible. Many oil reservoirs are reaching or have reached their maturity therefore secondary and tertiary methods for EOR have become increasingly important for sustainable volumes of oil to be produced. Reservoir simulators have become increasingly important in the pre-evaluation of these projects for proper reservoir management and evaluation. One of the most critical problems when considering the geologic storage of CO2 is the risk of leakage which can lead to seepage from the storage area. In Trinidad and Tobago (T&T) many reservoirs are highly faulted. Some faults form an integral part of the structural traps whilst others are leaky and provide migration pathways for the injected CO2 to return to surface. A simulation study was conducted using the commercial compositional simulator CMG-GEM. The model described in this paper seeks to optimize the injection of CO2 into an oil reservoir with some degree of compartmentalization due to faulting whilst maximizing the amount of incremental oil that can be produced. One of the main considerations will be to maximize the sweep efficiency below the fracture pressure and fault entry pressure. The model is intended for a type of formation likely to be used for storage in Trinidad. We conducted sensitivity analysis on the injection rate and fault transmissibity in an analogous field to those located offshore Trinidad. It was concluded that faults transmissibility affect the overall production of oil reservoirs. Sealing faults stored less CO2 and had less cumulative production than non sealing faults.

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