Compositional Modeling for Optimum Design of Water-Alternating CO2-LPG EOR under Complicated Wettability Conditions

The addition of LPG to the CO2stream leads to minimum miscible pressure (MMP) reduction that causes more oil swelling and interfacial tension reduction compared to CO2EOR, resulting in improved oil recovery. Numerical study based on compositional simulation has been performed to examine the injectivity efficiency and transport behavior of water-alternating CO2-LPG EOR. Based on oil, CO2, and LPG prices, optimum LPG concentration and composition were designed for different wettability conditions. Results from this study indicate how injected LPG mole fraction and butane content in LPG affect lowering of interfacial tension. Interfacial tension reduction by supplement of LPG components leads to miscible condition causing more enhanced oil recovery. The maximum enhancement of oil recovery for oil-wet reservoir is 50% which is greater than 22% for water-wet reservoir. According to the result of net present value (NPV) analysis at designated oil, CO2, propane, and butane prices, the optimal injected LPG mole fraction and composition exist for maximum NPV. At the case of maximum NPV for oil-wet reservoir, the LPG fraction is about 25% in which compositions of propane and butane are 37% and 63%, respectively. For water-wet reservoir, the LPG fraction is 20% and compositions of propane and butane are 0% and 100%.

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Techno-economic analysis of intermediate hydrocarbon injection on coupled CO2 storage and enhanced oil recovery

Energy Exploration & Exploitation ◽

10.1177/0144598720927078 ◽

2020 ◽

pp. 014459872092707 ◽

Cited By ~ 1

Author(s):

Jinhyung Cho ◽

Moon S Jeong ◽

Young W Lee ◽

Hye S Lee ◽

Kun S Lee

Keyword(s):

Economic Evaluation ◽

Economic Analysis ◽

Enhanced Oil Recovery ◽

Mole Fraction ◽

Oil Recovery ◽

Net Present Value ◽

Geological Storage ◽

Liquefied Petroleum Gas ◽

Present Value ◽

Oil Viscosity

This study proposes economic evaluation of CO2 geological storage with enhanced oil recovery. The procedures consider capital expenditures and operating costs of infrastructures and revenues from oil recovery and carbon tax credits. Extensive CO2 geological storage with enhanced oil recovery simulations was conducted to determine the most promising scenario among cases, where miscibility was controlled by the addition of liquefied petroleum gas. The addition of liquefied petroleum gas into a CO2 injection stream can accelerate reduction of oil viscosity, interfacial tension, and oil density, which cause improved displacement efficiency. The larger was the amount of liquefied petroleum gas injected, the greater was the miscibility due to minimum miscibility pressure reduction, resulting in higher oil recovery and less CO2 sequestration. Although liquefied petroleum gas addition enhances the performance of CO2 enhanced oil recovery, economic analysis should be conducted for CO2 geological storage with enhanced oil recovery due to the higher price of liquefied petroleum gas than that of CO2. Net present value decreased from liquefied petroleum gas mole fraction of 0–2% and started to increase from mole fraction 2–13% due to the miscibility effect. Then, net present value started to decrease, because the purchasing and injecting prices of the required liquefied petroleum gas exceeded that of the oil produced. Economic evaluation showed that addition of 13% liquefied petroleum gas was the most promising scenario, with a net present value of 91 MM$. Thus, we confirmed an optimum liquefied petroleum gas concentration in the CO2 geological storage with enhanced oil recovery process.

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Optimization of engineered water injection performance in heterogeneous carbonates: a numerical study on a sector model

Journal of Petroleum Exploration and Production Technology ◽

10.1007/s13202-020-00912-6 ◽

2020 ◽

Vol 10 (8) ◽

pp. 3803-3826

Author(s):

Jamiu Oyekan Adegbite ◽

Emad Walid Al-Shalabi

Keyword(s):

Sensitivity Analysis ◽

Oil Recovery ◽

Net Present Value ◽

Numerical Study ◽

Water Injection ◽

Design Parameters ◽

Present Value ◽

Tax Rate ◽

Sector Model ◽

Evolution Algorithms

Abstract One of the emerging technologies for boosting oil recovery in both sandstone and carbonate reservoirs is engineered/low-salinity water injection (EWI/LSWI). In this paper, optimization of engineered water injection is investigated using three synthetic sector models representing homogeneous, heterogeneous with channeling, and heterogeneous with gravity underride reservoirs. Both oil recovery and net present value were investigated as objective functions for the study. Eighteen design parameters were selected for the study including reservoir, operational, and economic parameters. Response Surface Methodology and Designed Exploration and Controlled Evolution algorithms were implemented for sensitivity analysis and optimization studies, respectively. The study highlighted that NPV is more representative as an objective function compared to oil recovery where the three optimized models have about similar oil recovery, but different NPVs. The sensitivity analysis showed that oil price, tax rate, and initial oil saturation are the three most influential design parameters on the net present value for the three models investigated. Moreover, the findings showed that developing the gravity underride model requires more attention as being the most sensitive model with 13 influential design parameters. The optimization study highlighted that secondary EWI is recommended to achieve the best profitability out of the three models. However, a high maximum exposure is expected due to the capital and operational costs related to early EWI application. This study is one of the very few that discusses the economic aspect of EWI while incorporating the complexity of geochemical reactions and the heterogeneity of carbonates.

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Undersaturated Hydrocarbon Reservoir Waterflooding: A simulation Approach to Performance Assessment

10.2118/207148-ms ◽

2021 ◽

Author(s):

Adekunle Tirimisiyu Adeniyi ◽

Miracle Imwonsa Osatemple ◽

Abdulwahab Giwa

Keyword(s):

Oil Recovery ◽

Net Present Value ◽

Oil Production ◽

Base Case ◽

Present Value ◽

Sweep Efficiency ◽

Recovery Method ◽

Solution Approach ◽

Hydrocarbon Reservoir

Abstract There are a good numbers of brown hydrocarbon reservoirs, with a substantial amount of bypassed oil. These reservoirs are said to be brown, because a huge chunk of its recoverable oil have been produced. Since a significant number of prominent oil fields are matured and the number of new discoveries is declining, it is imperative to assess performances of waterflooding in such reservoirs; taking an undersaturated reservoir as a case study. It should be recalled that Waterflooding is widely accepted and used as a means of secondary oil recovery method, sometimes after depletion of primary energy sources. The effects of permeability distribution on flood performances is of concerns in this study. The presence of high permeability streaks could lead to an early water breakthrough at the producers, thus reducing the sweep efficiency in the field. A solution approach adopted in this study was reserve water injection. A reverse approach because, a producing well is converted to water injector while water injector well is converted to oil producing well. This optimization method was applied to a waterflood process carried out on a reservoir field developed by a two - spot recovery design in the Niger Delta area of Nigeria that is being used as a case study. Simulation runs were carried out with a commercial reservoir oil simulator. The result showed an increase in oil production with a significant reduction in water-cut. The Net Present Value, NPV, of the project was re-evaluated with present oil production. The results of the waterflood optimization revealed that an increase in the net present value of up to 20% and an increase in cumulative production of up to 27% from the base case was achieved. The cost of produced water treatment for re-injection and rated higher water pump had little impact on the overall project economy. Therefore, it can conclude that changes in well status in wells status in an heterogenous hydrocarbon reservoir will increase oil production.

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