Enhanced aquathermolysis of extra-heavy oil by application of transition metal oxides submicro-particles in relation to steam injection processes

Xian Zhang,Hongchang Che,Yongjian Liu

doi:10.1007/s13202-021-01293-0

Abstract

In order to investigate the catalytic effects of transition metal oxides submicro-particles on aquathermolysis of Liaohe extra-heavy crude oil, the catalysts NiO, α·Fe2O3 and Co3O4 are used and evaluated during the experiments. The optimum mass fraction of the catalyst and water was determined to be 5.0 wt% and 30 wt%, respectively. The optimum reaction time for aquathermolysis was 24 h, and the optimum reaction temperature was 240 °C. The analysis results showed the heavy oil was upgraded dramatically by addition of the catalysts based upon viscosity reduction, saturate/aromatics/resins/asphaltenes analyses, elemental analysis, Fourier transform infrared spectroscopy and gas chromatography. All results show the heavy oil is in situ updated dramatically by catalytic aquathermolysis under the optimum operating conditions. A five-lump model is proposed for estimating kinetic parameters of aquathermolysis and agrees well with the experimental data.

Highlights

Heavy crude oils represent a significant share of the total oil reserves, and steam injection is the most commonly used method for recovering heavy crude oils (Santos et al 2014)
A total of thirteen components are included in the model, and the prediction of gas emissions is in line with the results reported from field
The results showed good agreement for bitumen conversion and evolved gases volumes

Summary

Introduction

Heavy crude oils represent a significant share of the total oil reserves, and steam injection is the most commonly used method for recovering heavy crude oils (Santos et al 2014). In the 1980s, the researchers discovered chemical reactions called aquathermolysis leading to in situ upgrading of heavy oils during steam injection processes (Clark and Hyne 1984). Smaller fragments are produced from organosulphur compounds and subsequently take part in a series of reactions during aquathermolysis, resulting in generation of smaller components such as H2S, CO2, CH4 and H2. Increases in light components and decreases in heavy components and significant viscosity reduction of heavy crude oils are observed after aquathermolysis in most of the literature (Kapadia et al 2015). Perez-Perez et al (2011) constructed a kinetic model to mimic H2S and CO2 emissions during aquathermolysis of Athabasca bitumen. The model was composed of seven reactions that represent production of non-condensable gases from Athabasca

Methods

Results

Conclusion