E. A. Araújo

Economical evaluation of heavy oil production from the Brazilian Northeast

ABSTRACT The technology involved for the recovery of heavy oils demands an insightful study of their technical and economic viability to make possible its implementation. Hence, this research proposes a study of the effects of managing the steam injection rate (Qinj), from the time the steam arrives to the producer well (steam breakthrough), in the oil recovery factor (RF), and net present value (NPV). For reaching these goals, numerical simulations were performed by using a heavy oil reservoir model representative of the Brazilian Northeast. By varying operational parameters, the behavior of the oil recovery factor and NPV was evaluated, for 15 years. Results showed that the injection of low steam injection rates, from the breakthrough time, resulted in improving the RF. Hence, this condition also promotes an improvement in the NPV, especially when there was injected 5 t/day after the breakthrough time.

Analysis of oil production by applying in situ combustion

ABSTRACT The THAI (toe-to-heel air injection) process is a process of enhanced oil recovery, which consists of integrating the in situ combustion process with technological advances of horizontal wells drilling, and has not yet been applied in Brazil. Motivated by this context, the authors aimed to studying the application of the THAI process in a semisynthetic reservoir, with characteristics similar to those ones found in the Brazilian Northeast. It was analyzed the air injection rate, indicating that there is a limit to reach a good efficiency.

Economic analysis of oil production by applying in situ combustion

ABSTRACT THAITM (Toe-to-Heel Air Injection) is a process of enhanced oil recovery, not yet applied in Brazil, which consists of integrating the in situ combustion process with technological advances of horizontal well drilling. Motivated by this fact, this research aimed at studying the application of the THAITM process in a semi-synthetic reservoir, with characteristics similar to those found in the Brazilian Northeast. The air injection rate was analyzed, indicating that there is a limit to reach the highest efficiency and improve the net present value (NPV).

Analysis of oxygen production by applying in situ combustion

ABSTRACT THAI (toe-to-heel air injection) is a process of enhanced oil recovery that consists of integrating the in situ combustion process with technological advances of horizontal wells drilling, and has not yet been applied in Brazil. Motivated by this context, this research aimed at studying the application of the THAI process in a semisynthetic reservoir, with characteristics similar to those found in the Brazilian Northeast. It was analyzed the air injection rate and produced oxygen, indicating that there is a limit to reach a good efficiency and minimized risk explosion.

Study of thermal efficiency in heavy oil reservoirs submitted to steam injection by using numerical simulation

Abstract In the steam injection applied to heavy oil recovery, just a fraction of the supplied heat can effectively heat the reservoir. To account this effect, it is possible calculating the fraction of the remaining heat, known as the reservoir’s thermal efficiency. This paper presents a comparative study of the thermal efficiency calculation, obtained from a numerical simulator and analytic models proposed by Marx and Langenheim (1959), by using reservoir parameters and operational parameters of steam injection. Among the obtained results, it was verified similarity between the analytic and numeric models, before the steam breakthrough. However, after the breakthrough, the thermal efficiency presented lower values for the numerical model, because the analytic model does not consider heat losses for producer wells, while that other model considers it.