Scaled Model Studies Of Solvent-Steam Injection, Under Bottom Water Conditions

1989 ◽  
Author(s):  
D. Oracheski ◽  
S. Farouq Ali ◽  
A. George
Keyword(s):  
Bottom Water ◽  
Steam Injection ◽  
Scaled Model ◽  
Model Studies ◽  
Water Conditions

Steamflooding Wabasca Tar Sand Through the Bottomwater Zone--Scaled Model Tests

1983 ◽  
Vol 23 (01) ◽  
pp. 92-98 ◽  
Author(s):  
Hans H.A. Huygen ◽  
W.E. Lowry
Keyword(s):  
Bottom Water ◽  
Surface Mining ◽  
Steam Injection ◽  
Laboratory Model ◽  
Layer By Layer ◽  
Scaled Model ◽  
Oil Saturation ◽  
Tar Sands ◽  
Steam Flooding ◽  
Water Zone

Abstract Steam flooding a tar sand with a communicating bottom-water zone was investigated in a three-dimensional, scaled, laboratory model. Scaling is discussed and equipment and procedures are described. We studied the process mechanisms and the influence of steam rate and initial oil saturation, and compared performance of single and multiple patterns. The bottom water was found to counteract gravity segregation of the steam. If the steam rate is high enough, no gravity override occurs, and much of the formation is swept layer by layer, resulting in high recovery of oil. But oil/steam ratios are rather low, particularly at low initial oil saturation and in the single pattern pilot where oil bypasses the production wells. Introduction In a world of decreasing conventional oil reserves, a number of alternative sources of hydrocarbons are being evaluated. One of the major alternatives, because of its size, is tar sands. Deposits are located primarily in Canada and Venezuela; each has an estimated reserve of nearly 1 trillion bbl (159 × 10(9) m3). At present, only 10% of these tar sands are shallow enough to be recovered economically by surface mining, pointing to the need for methods of in-situ recovery for the remaining 90%. Steam injection is highly effective in delivering heat and work to a tar sand. Heat raises the temperature of the tar, which greatly reduces its viscosity, thus increasing the reservoir fluid flow potential. Work provides the drive to recover the mobilized oil from tar sands that normally have no primary production. Steam drives exhibit good sweep and displacement efficiencies, even in heavy oil and tar reservoirs, because of the favorable effects of steam condensation. The principal problem in tar sands is the lack of injectivity caused by the very low mobility of the highly viscous tar, even though permeability of the sand is high. Steam could be injected above fracturing pressure or into a naturally permeable channel like a bottom water zone. But control and prediction of the direction, the orientation, and the extent of fractures in tar sands are uncertain. By contrast, a bottom water zone is already in the right location, linking wells, and allowing high steam injection rates. A disadvantage is that the water zone may be too thick, soaking up heat and oil. Gulf Canada Resources Inc. (GCRI) holds leases in Wabasca, Alta., which contain a very viscous, 6 degrees API (1.029-g/cm3) tar [5 million cp at the reservoir temperature of 55 degrees F (5 kPas at 13 degrees C)] in an unconsolidated sand. The deposit is located at a depth of about 800 ft (244 m) and consists of a 32- to 36-ft (10-m) oil zone overlying an 8- to 9-ft (2.5-m) bottom water zone, thought to be at least in partial communication. Permeability averages 400 md vertically and 1,000 md horizontally. The tar is high in asphaltenes and shows no significant distillation at anticipated steam temperatures. Various laboratory studies have been reported in the literature. Pursley steam flooded Cold Lake crude in a 500-psi (3.5-MPa) scaled model and concluded that steaming through a bottom water recovers more oil than steaming through a gas cap. Bursell and Pittman studied the behavior of Kern River crude in a 300-psi (2.1-MPa) model. SPEJ P. 92^

OSTRACOD-BASED RECONSTRUCTION OF BOTTOM WATER CONDITIONS IN THE INNER SEA OF THE MALDIVES DURING THE PLEISTOCENE (IODP SITE U1467, NORTHERN INDIAN OCEAN)

2017 ◽  
Author(s):  
Carlos A. Alvarez Zarikian ◽  
◽  
Chimnaz Nadiri ◽  
Montserrat Alonso-Garcia ◽  
Loren Petruny ◽  
...  
Keyword(s):  
Indian Ocean ◽  
Bottom Water ◽  
Northern Indian Ocean ◽  
Water Conditions

Millennial-scale changes of surface and bottom water conditions in the northwestern Pacific during the last deglaciation

2017 ◽  
Vol 154 ◽  
pp. 33-43 ◽  
Author(s):  
Sunghan Kim ◽  
Boo-Keun Khim ◽  
Ken Ikehara ◽  
Takuya Itaki ◽  
Akihiko Shibahara ◽  
...  
Keyword(s):  
Bottom Water ◽  
Northwestern Pacific ◽  
Last Deglaciation ◽  
Water Conditions ◽  
The Last Deglaciation ◽  
Millennial Scale

Seasonal variability of natural methane seepage offshore Western Svalbard

2021 ◽  
Author(s):  
Manuel Moser ◽  
Knut Ola Dølven ◽  
Bénédicte Ferré
Keyword(s):  
Gas Hydrate ◽  
Bottom Water ◽  
Methane Flux ◽  
Mixing Rate ◽  
Bottom Water Temperature ◽  
Acoustic Data ◽  
Methane Seepage ◽  
Continental Shelves ◽  
Water Conditions ◽  
Methane Fluxes

<p>Natural methane seepage from the seafloor to the water column occurs worldwide in marine environments, from continental shelves to deep-sea basins. Depending on water depth, methane fluxes, and mixing rate of the seawater, methane may partially reach the atmosphere, where it could contribute to the global greenhouse effect. Estimates of annual marine methane fluxes are commonly calculated from hydro-acoustic data collected during single research surveys. These snapshot estimates neglect short (i.e., tide) and long (seasonal) variations.</p><p>Here we compare the seepage activity along the upper limit of the gas hydrate stability zone offshore Western Svalbard in August 2017 (bottom water temperature (BT) ~3.46°C), June 2020 (BT ~1.75°C), and November 2020 (BT ~3.96°C) using high-resolution vessel-based multibeam data. Our results complete annual methane flux estimates by Ferré et al. (2020) and confirm a significantly reduced seepage activity during the cold bottom-water conditions. We investigate short-term variation by comparing a 7.5 km long multibeam section at three phases of the lunar semidiurnal (M2) tide. We will discuss how these processes affect annual methane fluxes estimates offshore Svalbard and further Arctic methane fluxes estimates.</p><p>The research is part of the Centre for Arctic Gas Hydrate, Environment and Climate (CAGE) and is supported by the Research Council of Norway through its Centres of Excellence funding scheme grant No. 223259 and UiT.</p><p> </p><p>Ferré, B., Jansson, P. G., Moser, M., Serov, P., Portnov, A., Graves, C. A., et al. (2020). Reduced methane seepage from Arctic sediments during cold bottom-water conditions. Nat. Geosci. 13, 144–148. DOI: 10.1038/s41561-019-0515-3</p>

Sign in / Sign up

Export Citation Format

Share Document