Low-Temperature Oxidation Kinetic Parameters for In-Situ Combustion Numerical Simulation

1987 ◽  
Vol 2 (04) ◽  
pp. 573-582 ◽  
Author(s):  
K.O. Adegbesan ◽  
J.K. Donnelly ◽  
R.G. Moore ◽  
D.W. Bennion
Keyword(s):  
Numerical Simulation ◽  
Low Temperature ◽  
Kinetic Parameters ◽  
Oxidation Kinetic ◽  
Low Temperature Oxidation ◽  
In Situ Combustion ◽  
Temperature Oxidation

Chemical-structural properties of the coke produced by low temperature oxidation reactions during crude oil in-situ combustion

Fuel ◽  
2017 ◽  
Vol 207 ◽  
pp. 179-188 ◽  
Author(s):  
Qianghui Xu ◽  
Zhiming Liu ◽  
Hang Jiang ◽  
Qiang Zhang ◽  
Cheng Zan ◽  
...  
Keyword(s):  
Low Temperature ◽  
Crude Oil ◽  
Structural Properties ◽  
Oxidation Reactions ◽  
Low Temperature Oxidation ◽  
In Situ Combustion ◽  
Temperature Oxidation

Behavior and Effect of SARA Fractions of Oil During Combustion

2000 ◽  
Vol 3 (05) ◽  
pp. 380-385 ◽  
Author(s):  
M.V. Kok ◽  
C.O. Karacan
Keyword(s):  
Low Temperature ◽  
Crude Oil ◽  
Combustion Process ◽  
Crude Oils ◽  
Low Temperature Oxidation ◽  
In Situ Combustion ◽  
Temperature Oxidation ◽  
Sara Fractions ◽  
Fuel Deposition

Summary In this study, saturate, aromatic, resin, and asphaltene fractions of two Turkish crude oils (medium and heavy) were separated by column chromatographic techniques. Combustion experiments were performed on whole oils and fractions by a thermogravimetric analyzer (TG/DTG) and differential scanning calorimeter (DSC) by using air and a 10°C/min heating rate. TG and DSC data were analyzed for the determination of weight loss due to possible reactions, and for reaction enthalpies of individual fractions, which have to be known for in-situ combustion technology utilization. Introduction In-situ combustion is a process of recovering oil thermally, by igniting the oil to create a combustion front that is propagated through the reservoir by continuous air injection. Success of such a process depends mainly on the crude oil properties and rock properties as well as operational conditions. In-situ combustion is considered as an effective process not only for heavy oil reserves but also for depleted light and medium oil reservoirs. Unfortunately, the lack of better understanding of the process variables in terms of the conversion of oil during combustion and reservoir characteristics, as well as the costs, limits the more effective application of this technology. In combustion, three different reaction regions were identified, known as low-temperature oxidation, fuel deposition, and high-temperature oxidation. In low-temperature oxidation (LTO), mainly small and weak chains of hydrocarbons are broken and pyrolyzed and oxidized to give ketones, alcohols, etc. In fuel deposition or middle-temperature oxidation, products of low-temperature oxidation are transformed to heavier hydrocarbons to be combusted at higher temperatures. High-temperature oxidation (HTO) is the main combustion region where hydrocarbons are fully oxidized by air. During the course of these processes, hydrocarbons are continuously converted to other types of hydrocarbons, which makes the combustion process very complicated. Heat values and reaction parameters of crude oils are also obtained from differential scanning calorimeter (DSC) thermogravimetry (TG/DTG) experiments. Many studies have been conducted on different phases of the in-situ combustion process, mainly on the fluid and rock interactions during combustion of the fluid phase. Vossoughi et al.1 concluded that the addition of clay to porous media significantly affected the combustion of crude oil. Bae2 investigated the thermo-oxidative behavior and fuel forming properties of various crude oils. The results indicated that oils could be classified according to their oxidation characteristics. Vossoughi3 has used TG/DTG and DSC techniques to study the effect of clay and surface area on the combustion of selected oil samples. The results indicate that there was a significant reduction in the activation energy of the combustion reaction regardless of the chemical composition of additives. Vossoughi and Bartlett4 have developed a kinetic model of the in-situ combustion process from thermogravimetry and differential scanning calorimeter. They used the kinetic model to predict fuel deposition and combustion rate in a combustion tube. Kok5 characterized the combustion properties of two heavy crude oils by DSC and TG/DTG. Individual fractions of the crude oils have been studied before in a variety of purposes in different reactions. Ciajolo and Barbella6 used thermogravimetric techniques to investigate the pyrolysis and oxidation of some heavy fuel oils and their separate paraffinic, aromatic, polar, and asphaltene fractions. The thermal behavior of fuel oil can be interpreted in terms of the low-temperature phase in which the polar and asphaltene fractions pyrolyze and leave a particular carbon residue. Ranjbar and Pusch7 studied the effect of oil composition, characterized on the basis of light hydrocarbons, resin, and asphaltene contents, on the pyrolysis kinetics of the oil. The results indicate that the colloidal composition of oil, as well as the transferability and heat transfer characteristics of the pyrolysis medium, has a pronounced influence on the fuel formation and composition. Karacan and Kok8 studied the pyrolysis behavior of crude oil saturate, aromatic, resin, and asphaltene (SARA) fractions to determine the effect of each constituent to the overall pyrolysis behavior of oils. Several authors, such as Geffen,9 Iyoho,10 and Chu11 have conducted feasibility studies for the in-situ combustion process. Yannimaras and Tiffin12 applied the accelerating rate calorimetry to screen crude oils for applicability of the air-injection/in-situ combustion process. Testing was performed at reservoir conditions for four medium and high gravity oils and results were compared with the combustion tube and air-injection/in-situ combustion process on the basis of continuity of the resulting plot in the region between the LTO and HTO reactions. Although combustion studies on both oil samples and oil-rock mixtures had been conducted, studies on the behavior of crude oil SARA fractions under an oxidizing environment and the investigations on the effects of each of these fractions to the whole oil combustion process have been scarce. This research was conducted to fulfill this partial need in the field of crude oil combustion. The results are aimed to serve for better understanding and accurate modeling of in-situ combustion by using the effects of individual fractions on whole oil combustion. This enables the operators to adapt the changes in the compositional properties of oil during combustion and fine tune the operational parameters.

A 3-Step Reaction Model For Numerical Simulation of In-Situ Combustion

2021 ◽  
Author(s):  
Allan A. Rojas ◽  
Chengdong Yuan ◽  
Dmitrii A. Emelianov ◽  
Emil R. Saifullin ◽  
Seyedsaeed Mehrabi-Kalajahi ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Oxygen Consumption ◽  
Low Temperature ◽  
Simulation Model ◽  
Reaction Model ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation ◽  
Oil Fractions ◽  
Isothermal Measurements

Abstract In-situ combustion (ISC) is an effective thermal enhanced oil recovery method. However, it is still not widely implemented in oilfields. One of the factors limiting the wide application of ISC is the challenge in its simulation and prediction. In this work, the oxidation experiments of maltenes and asphaltenes in reservoir rock were performed in the porous media thermo-effect cell (PMTEC) to establish a simplified reaction model based on non-isothermal measurements and to use it in numerical simulation of ISC process. It was found that the oxidation reaction process of oil fractions can be divided into different regions depending on generated self-energy rate and oxygen consumption rates that is up to the temperature. In order to propagate reactions from one mode to another, a specific oxygen consumption per unit mass of oil fractions is required. The average oxygen requirement for crossing LTOad (low temperature oxidation, oxygen addition reactions) boundary into LTC (low temperature combustion) mode was 64 mgO2/g(maltenes) and 10.4 mgO2/g(asphaltenes). To propagate reactions into HTO mode from the LTC mode, it requires about 646 mgO2/g(asphaltenes) for asphaltenes fraction. Moreover, this characterization seems to be a key tool when designing air injection in field pilots. Additionally, it was revealed that asphaltenes are more exothermic and require lower oxygen uptake per unit of temperature increment in comparison to maltenes. Furthermore, the mass conversion data obtained from non-isothermal measurements of oil fractions allow for the estimation of the stoichiometry coefficients of two low temperature oxidation reactions, i.e. oxidation and cocking processes, which can be included into a numerical simulation model to replicate combustion tube (CT) results. The numerical simulation model reveals that the simplified reaction model from a 6-step into a 3-step reaction scheme can reproduce ignition process, temperature profiles, combustion velocity, and fluid production, which thus makes it suitable for the upscaled modelling of ISC.

scholarly journals Kinetic Parameters for Biomass under Self-Ignition Conditions: Low-Temperature Oxidation and Pyrolysis

2019 ◽  
Vol 33 (9) ◽  
pp. 8606-8619 ◽  
Author(s):  
Lars Schwarzer ◽  
Zsuzsa Sárossy ◽  
Peter Arendt Jensen ◽  
Peter Glarborg ◽  
Oskar Karlström ◽  
...  
Keyword(s):  
Low Temperature ◽  
Kinetic Parameters ◽  
Low Temperature Oxidation ◽  
Temperature Oxidation
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