Experimental study and numerical simulation of nitrogen-assisted SAGD in developing heavy oil reservoirs

Impacts of pore size distribution on gas injection in intraformational water zones in oil sands reservoirs

“…Gao et al (2017) performed a study to select the most appropriate gas to deal with an oil sands reservoir with top water, and they recommended nitrogen for their study area. Yuan et al (2018) performed experimental and simulation studies to show that a Non-Condensable Gas (NCG) can decrease the consumption of steam and increase an oil rate. Wang et al (2019) employed an experiment to study the gas injection into an interlayer to improve the SAGD production performance, and their study indicated that a gas addition can help a SAGD steam chamber to break through the interlayer.…”

3D experimental investigation on enhanced oil recovery by flue gas assisted steam assisted gravity drainage

“…From 4000 min to 4600 min, due to the flue gas had relatively low density and weak heattransfer capability, and can firstly enter along the pore, reducing the seepage resistance of steam, the loss of steam along the way was also decreased and the heat exchange with the reservoir was more sufficient . Furthermore, nitrogen density was relatively low, which resulted in the diffusion coefficient was high, and the interfacial tension between nitrogen and heavy oil was small (Yuan et al, 2018), therefore, nitrogen readily expands longitudinally, the steam chamber was developed laterally again. The swept zone and saturation temperature zone encroached to the sides gradually, as shown in Figure 11 (a1) and (b1).…”

“…However, this technique also has some defects, including that high consumption of steam, serious heat loss, and incomplete steam chamber development, which restricts the oil recovery factor (Lawal, 2014;Li et al, 2013;Shin and Polikar, 2006). To solve the above problems, non-condensable gas such as flue gas and natural gas was proposed to inject into the production of SAGD (Butler, 1999;Butler et al, 1999;Butler et al, 2001), an abundance of subsequent experiments and simulations confirm that it could effectively reduce the heat loss of the top of the reservoir (Canas and Kantzas, 2012;Lin et al, 2012) by forming a heat insulation layer, expand the sweep range of the steam chamber (Fatemi,2010;Yuan et al, 2018), slow down the topwater drainage, contributing for improving the oil-steam ratio and the production of SAGD (Jiang et al, 2000;Li et al, 2011Li et al, , 2017Pang et al, 2017). In addition, by taking advantage of gas lifting, non-condensate gas, such as natural gas and carbon dioxide, can be injected into reservoir through the tubing, which can reduce crude oil density and bottomhole pressure, the fluidity of crude oil is enhanced and well production is increased.…”

Potential Analysis of Enhanced Oil Recovery by Superheated Steam during Steam‐Assisted Gravity Drainage

“…In addition, due to a large amount of gas generated, the effect of gas fingering on the expansion of the steam chamber was no longer apparent, and the increase in thermal resistance of the gases was dominant. [26] Figure 11 shows a quantitative description of the lateral expansion of the steam chamber. It is shown in Figure 11d that the steam chamber was pushed to expand by 1 and 3 m further in the horizontal direction by the steam of 20 and 50 of superheat compared with the saturated steam at the 1250th day.…”