Numerical Study of Belt Skimmer Performance

ABSTRACT

With the recent increases in sea traffic, these waterways have become a prime site for oil spill pollution. Tanker transportation and oil platforms are sources of potential risks of oil pollution. In case of accidental marine pollution, the authorities in charge of pollution shall response. Ideally there are six response alternatives to combat an oil spill:

1-      Monitor and evaluate.

2-      Disperse the oil with chemicals.

3-      Contain and recover the oil at sea.

4-      Protect vulnerable resources.

5-      Burning, and

6-      Clean up the shoreline.

These alternatives are well known. Some of them can cause more damage to the environment than the presence of the spill itself such as the chemical dispersants or burning the oil in the sea. Others prefer mechanical devices such as skimmers. Each of which has its own applications depending on manpower and the proper use of the selected techniques.

The objective of this work is to find the effect of the working parameters on the belt performance and to simulate the scene, which had seen in the experimental work.

The parameters that affect on belt skimmer performance are namely the belt speed (Vbelt), the belt inclination angle (), the oil viscosity (), the oil film thickness (T), and the oil surface tension ().

Starting from N.S.E (Navier Stocke’s Equations) in the incompressible fluid flow form with a constant viscosity. Using assumptions and boundary conditions (B.C.) to get the equations of velocity distribution and volume flow rate for the flow over belt surface in the downward and upward directions and to get the equations of motion for the flow over water surface.

  •  For the flow over belt surface, the velocity distribution and the skimmed flow can be theoretically estimated. Also, an empirical formula for the oil height over belt surface was obtained.
  • For the flow over water surface, a model of grids is developed for the recovery area (the area between the boom and the skimmer). The model is a two-dimensional finite element model. After a finite element mesh has been constructed and boundary conditions have been defined, the flow velocity at each grid point can be computed. So, the model can simulate the oil circulation over water surface, draw velocity distribution through the oil film thickness and calculate the compensating oil.

Also, The relation between the skimmed volume flow rate, compensating volume flow rate and Oil Recovery Rate (ORR) are discussed.

Supervisors: Prof. Hassan A. Warda.

                             Ass. Prof. Ihab Adam.

 

Thesis