BLG 4/18
ANNEX 7
PROPOSED AMENDMENTS TO SECTION 9 OF THE STANDARD FORMAT FOR THE COW MANUAL
(RESOLUTION MEPC.3(XII)
Section 9 of the Standard Format for the COW Manual is replaced by the following:
"SECTION 9 DETERMINATION OF THE SUITABILITY OF A CRUDE OIL FOR USE IN CRUDE OIL WASHING"
This section contains guidance in determining the suitability of a crude oil for use in crude oil washing.
In lieu of a list of crude oils unsuitable for carriage and crude oil washing to be inserted in the Crude Oil Washing and Equipment Manual the following standard text maybe used:
(1) For a Tanker not fitted with heating coils.
This tanker is not fitted with heating coils in the cargo tanks and should not carry cargoes which will require to be heated either to obtain pumpability criteria or to avoid excessive sludging of both the designated clean ballast tanks and the vessel's tanks to be washed for sludge control.
Notes and Definitions:
C Pumpability Criterion is determined by the oil's Kinematic Viscosity at the observed temperature of the cargo prior to its discharge. In order to attain optimum efficiency for discharge this viscosity should not exceed 250 centistokes and never in excess of 600 centistokes.
C Excess sludging criterion is determined primarily by the crude oil's temperature throughout its transportation and storage. If the cargo's temperature is likely to drop below the crude oil cargo's cloud point temprerature then sludging of cargo tanks to be expected. The cloud point temperature is the temperature at which the crude oil's wax and associated oil phase separates from the bulk liquid phase of the cargo.
(2) For a Tanker fitted with heating coils in Slop Tank(s)
This tanker is fitted with heating coils only in her Slop Tank(s) and should not carry cargoes which will require to be heated for pumpability.
Notes:
If sludge deposition is suspected or determined in the main cargo tanks then an alternative crude oil washing programme should be utilised. Recommendations regarding this programme and procedure are to be found in Section 11 of this manual.
