Not all oil pollution is caused by tankers. However, the huge volume of crude oil transported by sea has created a major problem in disposing of dirty ballast and tank washings without harming the marine environment or damaging coastal amenities. Most crude oils contain wax and other materials in solution, together with sediments, which may settle out during the voyage and form a residue with any cargo remaining after discharge (of the order of 0.2 to 0.5 per cent of the cargo carried). If discharged into the sea in heavy concentrations in the course of tank washing the residue will stay on … [Read more...]
Piping Arrangement – Conventional Oil Tanker Basics
The arrangement of loading and discharge lines is collectively known as the Ship’s Cargo System. The first oil tankers to carry petroleum products in bulk were equipped with very simple pumping systems. For the most part, they had a single line which ran forward and aft from a midship pump-room, in which were housed two steam reciprocating pumps. One pump served the tanks forward of the pump-room, while the other dealt with the oil from the tanks aft of this pump-room. Some of the more simple types with their engines amidships provided pumps in the engine room to handle the cargo, or … [Read more...]