In-situ Combustion Simulation from Laboratory to Field Scale

Zhouyuan Zhu,Yang Song,Canhua Liu,Yuning Gong,Junshi Tang,Yajing Chen,Qiqing Wang

doi:10.1155/2021/8153583

Abstract

In-situ combustion simulation from laboratory to field scale has always been challenging, due to difficulties in deciding the reaction model and Arrhenius kinetics parameters, together with erroneous results observed in simulations when using large-sized grid blocks. We present a workflow of successful simulation of heavy oil in-situ combustion process from laboratory to field scale. We choose the ongoing PetroChina Liaohe D block in-situ combustion project as a case of study. First, we conduct kinetic cell (ramped temperature oxidation) experiments, establish a suitable kinetic reaction model, and perform corresponding history match to obtain Arrhenius kinetics parameters. Second, combustion tube experiments are conducted and history matched to further determine other simulation parameters and to determine the fuel amount per unit reservoir volume. Third, we upscale the Arrhenius kinetics to the upscaled reaction model for field-scale simulations. The upscaled reaction model shows consistent results with different grid sizes. Finally, field-scale simulation forecast is conducted for the D block in-situ combustion process using computationally affordable grid sizes. In conclusion, this work demonstrates the practical workflow for predictive simulation of in-situ combustion from laboratory to field scale for a major project in China.

Highlights

In-situ combustion (ISC) is an enhanced oil recovery (EOR) method in which air is injected into a reservoir to burn small amount of the crude oil to generate heat, driving the remaining oil towards the producers [1,2,3]
We demonstrate the ISC simulation workflow from laboratory to field scale for D block in Liaohe Oilfield
We present the following specific conclusions: (1) The reaction kinetics of D block crude is characterized in the kinetic cell (RTO) experiment, through ramping of temperature and measurement of flue gas compositions

Summary

Introduction

In-situ combustion (ISC) is an enhanced oil recovery (EOR) method in which air is injected into a reservoir to burn small amount of the crude oil to generate heat, driving the remaining oil towards the producers [1,2,3]. Serious grid size effect and numerical error are observed, mainly because the mass and energy conservation equations in commercial thermal reservoir simulator are solved with the Arrhenius kinetic reaction terms calculated using the average grid block properties that result in poor spatial and temporal resolution of the reaction front This often leads to an excessive amount of fuel consumed, reaction zone temperature being too high and slower movement of the reaction front, when large-sized grid blocks are used in field-scale simulations. A novel reaction upscaling method has been proposed in order to minimize the grid size effect in fieldscale ISC simulations [14, 15] Both the temporal and spatial scales of kinetics and advection are very different in the ISC process. This work provides a practical guideline for the predictive numerical simulation and process design for ISC

D Block In-situ Combustion Field Description

Characterization of Reaction Kinetics

Simulation of 1D In-situ Combustion Displacement Process

Reaction Upscaling for Large-Scale In-situ Combustion Simulation

Field-Scale Simulation of D Block In-situ Combustion Process

Conclusions