Tanker Familiarization Tanker Systems and Equipment 3

Question 1

What is the purpose of a crude oil washing (COW) system on a tanker?

Accepted Answer

To use cargo crude oil as a solvent to clean tank residues during discharge

Answer

COW systems spray crude oil at high pressure inside tanks during discharge, dissolving wax and sediment to maximize cargo recovery and reduce manual cleaning.

Question 2

A tanker's slop tank is used primarily to:

Accepted Answer

Collect tank washing water and oily residues

Answer

The slop tank collects dirty wash water and oily residues from cargo tank cleaning, allowing oil and water to separate before controlled disposal.

Question 3

Which component of the cargo pump system prevents reverse flow when the pump stops?

Accepted Answer

Non-return (check) valve

Answer

A non-return (check) valve automatically closes to prevent backflow of cargo when the pump loses pressure or shuts down.

Question 4

What does the term 'ullage' refer to in cargo measurement?

Accepted Answer

The distance from the liquid surface to the top of the tank

Answer

Ullage is the empty space above the liquid in a tank, measured from the reference point at the top; cargo volume is calculated from ullage tables.

Question 5

On a tanker, what is the function of a 'vapor recovery system'?

Accepted Answer

To capture cargo vapors during loading for safe disposal or return to shore

Answer

Vapor recovery systems collect hydrocarbon vapors displaced from tanks during loading and return them to shore facilities, reducing emissions and explosion risk.

Tanker Familiarization Practice Test

Tanker Familiarization Practice Test

Tanker Familiarization Tanker Systems and Equipment 3