The development of crude-oil washing for the tanks of crude-oil carriers over the past few years is outlined, and the advantages of the system are discussed. A study, based on published data and the experience of ship operators, is then made of the economic incentive for installing the system in an existing 230,000/250,000-dwt tanker, equipped with an inert-gas system, operating between the Persian Gulf--a Spanish port (Cartegena), a round voyage of 65 days. The study, covering an operating period of two years, is discussed in some detail, and it is found that fitting the COW system would result in considerable net gains to the operator. Quantitative data are included on these net gains, which take into account the value and freight charges of the crude oil recovered by the system, and a number of other items, including the amortisation of the cost of the retrofit. The design and layout of a crude-oil washing system for an existing tanker, and the installation of the system without undue interference with the ship's normal operations, are also discussed in some detail, and several recommendations are made. Practical information is given on the operation of a tanker fitted with the system, and the cargo discharge and crude-oil washing of a 170,000-dwt vessel, in accordance with a pre-arranged plan, is described by way of example. Some advice, based on experience with a Spanish tanker, is included on the ballasting operations associated with crude-oil washing. In addition to its use in meeting anti-pollution regulations, COW may be considered necessary because of its economic and operational advantages. Operating the system should not be regarded as a routine matter, but it is not difficult provided that the ship's officers have the right attitude and appropriate training.

  • Corporate Authors:

    Asociacion de Ingenieros Navales

    Apdo Correos 457
    Madrid,   Spain 
  • Authors:
    • Casali, S M
  • Publication Date: 1979-11


  • Spanish

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00310903
  • Record Type: Publication
  • Source Agency: British Ship Research Association
  • Files: TRIS
  • Created Date: May 7 1980 12:00AM