Feasibility Study on Steam and Gas Push with Dual Horizontal Wells in a Moderate - Depth Heavy Oil Reservoir

Abstract

Non-condensable gas (NCG) with steam co-injection makes steam assisted gravity drainage less energy-intensive as well as reduces greenhouse gas emission and water consumption. Numerous studies have shown that the technology called steam and gas push (SAGP) is feasible for heavy oil and bitumen. However, most of these studies have focused on shallow heavy oil reservoirs and only a few works have investigated moderate-depth heavy oil reservoirs. In this study, laboratory experiments and numerical simulations were conducted to study shape change, steam chamber expansion, and temperature change after co-injecting NCG with steam into an actual moderate-depth heavy oil reservoir. Results showed that after co-injecting NCG with steam, the transverse expansion rate of the steam chamber accelerated, vertical expansion slowed down, thermal utilization increased, and oil-steam ratio improved. In addition, the injection parameters of SAGP were also optimized via numerical simulation, which indicated that SAGP could effectively improve development effect and recovery for moderate-depth heavy oil reservoirs.

Experimental study on the mechanism and development effect of multi-gas assisted steam huff and puff process in the offshore heavy oil reservoirs

“…What's more, as the pressure decreases in the course of development, CO 2 and N 2 will extract from crude oil and generate dissolved gas drive in the later stage. In view of these, injection CO 2 and N 2 would have positive effect for production heavy oil in the course of steam injection (Hong and Ault 1984;Butler et al 2000;Fan et al 2016;Jin et al 2017;Yan et al 2020).…”

Experimental study on horizontal-well multi-thermal fluid stimulation process in offshore heavy oil reservoirs

“…Heavy oil with the viscosity of less than 350 mPa•s can be effectively developed by water flooding as well as a series of techniques such as chemical flooding, well pattern thickening, and so on (Ji 2012). However, just limited reserves could be developed by the cold recovery technology for heavy oil with the viscosity greater than 350 mPa s; at this time, steam injection will show its unique advantages and high recovery (Fengrui et al 2017a, b, c;Fan et al 2016).…”