Skimmer Capacity for Viscous Oil
- Vidar W. Moxness (Norwegian University of Science and Technology) | Knut Gåseidnes (Reninor) | Harald A. Asheim (Norwegian University of Science and Technology)
- Document ID
- Society of Petroleum Engineers
- SPE Journal
- Publication Date
- March 2011
- Document Type
- Journal Paper
- 155 - 161
- 2011. Society of Petroleum Engineers
- 6.5.5 Oil and Chemical Spills, 5.3.2 Multiphase Flow
- experimental, pollution control, segregated flow, oil spill, skimmer
- 3 in the last 30 days
- 335 since 2007
- Show more detail
- View rights & permissions
|SPE Member Price:||USD 12.00|
|SPE Non-Member Price:||USD 35.00|
When a skimmer removes oil locally, oil floating further away will flow toward it. The maximum flow rate toward the skimmer defines its natural capacity. Traditional skimmer-capacity modeling considers flow driven by height potential and resisted by inertial forces but neglects viscosity. On the basis of theory and experiments, this paper claims that high oil viscosity may govern the skimmer capacity.
It is shown that viscous resistance relates to a dimensionless quantity called the Goose number, representing the ratio of inertial to viscous forces. At high Goose numbers, viscosity may be neglected. At sufficiently low Goose numbers, viscous resistance dominates. A numerical solution applicable to all Goose numbers has been developed. Analytical formulas for skimmer capacity at high and low Goose numbers are provided.
A scaled laboratory facility was built to investigate the skimming of viscous oil. The measured rates were consistent with the numerical predictions and with the formula for low Goose number. With decreasing viscosity, predictions by the current model converged to traditional formulas that neglect viscosity.
The model quantifies how skimming capacity is affected by size and by properties of the oil spill and skimmer geometry and submergence. This may enable more rational skimmer design and operation, and even optimization.
|File Size||610 KB||Number of Pages||7|
Craya, A. 1949. Recherches Théoriques sur L'Écoulement de CouchesSuperposées de Fluides de Desités Differentes. La Houilles Blanch(January-February): 44-55.
Cross, R.H. III and Hoult, D.P. 1971. Collection of Oil Slicks. ASCEJournal of Waterways, Harbors and Coastal Engineering Division (May 1971):313-322.
Gariel, P. 1949. Recherches Experimentales sur L'Écoulement de CouchesSuperposées de Fluides de Desités Differentes. La Houilles Blanch(January-February): 56-64.
Griffiths, R.A. 1976. Performance Tests of Off-The-Shelf Oil Skimmers. PaperOTC 2696 presented at the Offshore Technology Conference, Houston, 3-6 May.
Imberger, J. 1980. Selective withdrawal: A review. Proc., 2ndInternational Symposium on Stratified Flows, Trondheim, Norway, 24-27 June,Vol. 1.
Koh, R.Y.C. 1966. Viscous stratified flowtowards a sink. Journal of Fluid Mechanics 24 (3):555-575. doi: 10.1017/S002211206600082X.
Leibovich, S. 1977. Hydrodynamics Problems in Oil-SpillControl and Removal. J Pet Technol 29 (3): 311-324;Trans., AIME, 263. SPE-5469-PA. doi: 10.2118/5469-PA.
Lichte, H.W. and Breslin, M.K. 1978. Testing Skimmers for Offshore SpilledOils. Paper OTC 3076 presented at the Offshore Technology Conference, Houston,8-11 May.
Lister, J.R. 1989. Selective withdrawal from a viscous two-layer system.J. Fluid Mechanics 198 (8): 232-254.
Moxness, V.W. 2006. Tilstrømning av oljesøl til sluk. MS thesis, Instituttfor petroleumsteknologi og anvendt geofysikk, NTNU, Trondheim, Norway.
Munson, B.R., Young, D.F., and Okiishi, T.H. 1998. Fundamentals of FluidMechanics, third edition. New York: John Wiley & Sons.
Nåvik, K.S. 1994. Tilstrømming til sluk. MS thesis, Institutt for geologi ogbergteknikk, NTNU, Trondheim, Norway.