Heavy oil recovery

Initially, steam is injected into the formation for a period of time by way of an injection well and a production well. Thereafter, a combustion-supporting gas is injected through the injection well into the top of the formation to form a fluid conductive path between injection and production wells. Subsequently, steam is injected into the formation, preferably near the bottom of the formation and flows through the fluid conductive path. Heated oil adjacent to the top of the formation is produced by steam drag into the producing well or wells. 

Air has also been used in heavy oil reservoirs to generate heat and steam to mobilize oil in place. For light oil applications however, the in situ generated flue gas (85% N2 + 15% CO2) is the main driving force for oil displacement. The flue gas pressures up the reservoir, mobilizes, strips, and swells the oil in place, and at sufficient pressures can result in miscible and near-miscible displacement of the oil. For deeper reservoirs, the generated supercritical steam (above 22.1 MPa and 374 °C) also efficiently extracts and displaces in situ crude oil components. 

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Table 8. Projects for Bitumen and Heavy Oil Recovery/Conversion...

A linear correlation is obtained between bitumen extraction with the paddle mill and the adhesion tension against water saturated pyrophyllite. That the degree of water saturation of the pyrophyllite is important in explaining the difference between the 2 extraction processes indicates that it will be necessary to study each process in terms of the relevant adhesion tensions. These results demonstrate that adhesion tension is the most important parameter found to date in determining the degree of separation in the presence of surfactants. Measurements of adhesion tension between surfactant solutions and minerals similar to those found in tar sand may be of considerable value in studies of surfactant utility in both aqueous-surfactant, solvent-aqueous-surfactant and in situ extraction processes. In addition, if appropriate model situations can be developed, measurements of adhesion tension may be useful in upgrading bitumen-water-clay emulsions obtained by a variety of in situ and heavy oil recovery processes. 

Liu Q, Dong M, Ma S, Tu Y (2007) Surfactant enhanced alkaline flooding for western canadan heavy oil recovery. Colloids Surf A 293 63-71... 

Producing (well-bore) foams in cold, heavy-oil recovery G/O... 

Producing (well-head) solids in primary heavy oil recovery S/W ... 

Retention Time. To effectively demulsify an oil-in-water emulsion, it must be held at a suitable treating temperature for a specific time period. In the absence of experimental data, 20-30 min is usually a realistic estimate for retention time for conventional oil projects for heavy-oil recovery operations, retention times could be several hours. Nonetheless, the vessel geometry and specifications required for a specific retention time may not necessarily be the same as those dictated by the settling requirements. The solution is to select the larger geometry and dimensions determined by either of the two criteria. The retention time is determined as follows (3). For horizontal vessels. 

Inagaki, M., Toyoda, M., and Nishi, Y. (2001). Sorption, recovery and recychng of heavy oils by carbon materials. Kagaku Kougaku, 65, 179—82 (in Japanese). Inagaki, M., Toyoda, M., Iwashita, N., et al. (2001). Exfohated graphite for spilled heavy oil recovery. Carbon Sci., Korea, 2, 1-8. 

SYNERGY BETWEEN ALKALI AND SURFACTANT IN HEAVY OIL RECOVERY... 

Synergy between Alkali and Surfactant in Heavy Oil Recovery... 

Because heavy oils have higher content of acid components, alkali and oil reaction will generate in situ surfactant (soap). It is expected that alkalis would play a more important role in heavy oil recovery and the synergy between alkali and surfactant would be more significant. This section considers the work of Liu et al. (2006b) as an example to illustrate the alkaline-surfactant synergy in heavy oils. 

Bryan, J., Kantzas, A., 2007. Enhanced heavy-oil recovery by alkali-surfactant flooding. Paper SPE 110738 presented at the SPE Annual Technical Conference and Exhibition, Anaheim, 11-14 November. 

Dong, M., Ma, S., Liu, Q., 2009. Enhanced heavy oil recovery through interfacial instability A study of chemical flooding for Brintnell heavy oil. Fuel 88, 1049—1056. 

Produced (wellbore) foams in cold, heavy oil recovery Oil flotation process froths Firefighting foam Heavy oil pipeline emulsions Well stimulation emulsions Oil and oil sand flotation process emulsions Emulsion drilling fluid Oil-emulsion mud Oil-base mud Asphalt emulsion... 

Figure 9. Effect of Molecular Properties (e.g. Chain Length Compatibility) of Mixed Surfactants on Surface Properties of Foaming Agents, Bubble Size and Heavy Oil Recovery in Porous Media.

Table II. Heavy Oil Recovery by Steam Flooding in the Presence of Different Concentration of Calgon 835 Polymer. 

Sharma, M.K. and Shah, D.O., Interfacial Phenonena in Foam Flooding Process for Heavy Oil Recovery., 18th Intersociety Energy Conversion Engineering Conference, pp. 527-534 (1983). 

The thermal stability of several petroleum sulphonates and non-ionic surfactants has bem investigated in relation to heavy oil recovery by several workers . The stability of toe surfactants is reported in terms of toe time required for half of toe surfactant to decompose (i.e. half life). In order to determine toe half-lives for petroleum sulphonates at different temperatures, the activation energy... 

Many research laboratories are actively involved in investigating the use of surfactants in light and heavy oil recovery. Surfactant and foam flooding may become more widely acc ted as more is learned about the mechanism of oil displacement and as these processes are improved and tested in the fi. The contact of surfactants with residual oil. 

Major cogeneration applications are highly energy intensive and diverse, including such processes as those associated with heavy oil recovery, tar sands oil recovery, coal liquefaction, h-coal liquefaction, coal gasification, steel mill and aluminum mill processes. Several process heat applications were also considered in the design too, which are discussed in more detail later. 

Polymer Flood Application to Improve Heavy Oil Recovery at East Bodo... 

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