A Novel Air Flooding Technology for Light Crude Oil Reservoirs Applied under Reservoir Conditions

Abstract

A novel air flooding technology based on catalyst-activated low-temperature oxidation (CLTO) has been researched by static and dynamic oxidation experiments and can be applied in light crude oil reservoirs under reservoir conditions to improve the safety and oil recovery of air flooding. The catalytic effect of additives on the oxidation behavior of three crude oils was researched. The changes in oil recovery, oxygen distribution, and oil characteristics caused by additives were researched by dynamic oxidation experiments, and the influences of crude oil types, additive injection pattern, injection volume, and injection time on the catalytic effect were also researched. The results show that metallic additives can improve the oxygen consumption capacity of crude oils. Furthermore, the addition of additives can delay the oxygen breakthrough time and reduce the oxygen content in the gas produced. During the catalytic air flooding, the oxygen injected reacts mainly with the residual oil near the injection wells, and the influence of CLTO on the properties of oil produced from light oil reservoirs is minor. The key point to guarantee the success of catalytic air flooding is to select the optimal catalyst for the reservoir oil. The preferred catalyst injection pattern is catalyst alternating air injection, and the recommended catalyst injection volume is 0.03–0.05 PV. Catalytic air flooding technology can improve the safety and widen the application of air flooding technology.

Physical Simulation of Gas Injection Mechanism for High Dip Reservoir

“…Although the application scale of gas flooding is not as extensive as that of water flooding, it has continued to increase in recent years, providing another choice for reservoirs with poor water flooding effect or low adaptability. Considering factors such as reservoir development effectiveness, cost, environmental protection, and low carbon emissions, the types of gas sources are also diversified, which has resulted in the evolution of various gas drive methods, including nitrogen drive, air drive, associated gas reinjection, and carbon dioxide drive and so on [4][5][6]. Among them, due to the increased focus on global climate change in recent years, Carbon Capture, Utilization…”

Identification of Gas Channeling and Construction of a Gel-Enhanced Foam Plugging System for Oxygen-Reduced Air Flooding in the Changqing Oilfield

“…In addition, to prevent explosions and ensure the safety and controllability of air flooding, light oil reservoirs are usually flooded with oxygen-reduced air. Oxygen-reduced air flooding (ORAF) is a development method in which deoxidized air whose volume ratio of oxygen is reduced to less than 10% is injected into oil reservoirs to displace crude oil by utilizing deoxidized air generation and pressurized injection systems [ 7 , 8 , 9 ]. Besides maintaining the reservoir pressure, the low-temperature oxidation heat generation, flue gas flooding, and swelling effect can be fully utilized to enhance oil recovery (EOR) during the ORAF process.…”

Exothermal Property and Kinetics Analysis of Oxidized Coke and Pyrolyzed Coke from Fengcheng Extra-Heavy Oil

“…16,17 Additionally, the injected gas results in increasing the reservoir pressure and enhancing crude oil recovery. 18,19 In the ISC process, pyrolysis coke and oxidized coke can be deposited by heavy oil in a nitrogen or air atmosphere. 20−22 The oxidized coking and pyrolyzed coking mechanisms are significantly different.…”

“…In addition, China’s heavy oil resources are dominated by the northwest and Liaohe oilfield, representing more than 60% of the nation’s total oil. Due to the decreasing oil production of conventional and mature reservoirs coupled with the rapid increase in global energy demand in recent years, heavy oils have become an increasingly significant energy resource. − As an effective and potential thermal recovery method for heavy crude oil, in situ combustion (ISC) technology has been increasingly studied. , During the dynamic ISC process, a series of continuous and complex reactions, such as distillation volatilization, low-temperature oxidation (LTO), fuel deposition (FD), and high-temperature combustion (HTC), are generally believed to occur. − Oxygen addition reactions of some active aliphatic compounds are regarded as the main LTO reaction pathways that produce LTO derivatives. , Then, the coke precursors can further generate coke in the FD stage. − The available heat is released by coke combustion, which can promote the in situ cracking and upgrading of heavy oil. , These newly produced light fractions can be distilled into the gas phase and further migrate and condense. , Additionally, the injected gas results in increasing the reservoir pressure and enhancing crude oil recovery. , …”