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The LPG/Ethylene/Ammonia/VCM Carrier model is based upon a series of vessel which are classed as “Liquefied Gas Carrier”, (-104 °C, 5,0 bar gauge, 0.972 t/m3), Type 2G.The vessels cargo system consists of three main cargo tanks and an additional deck storage vessel.The vessel is designed to enable the carriage of two fully segregated cargoes in any of the main cargo tanks.

Detailed description:

  • Cargo System - The cargo system includes all the relevant pipelines for the movement of liquid, vapour and condensate around the vessel. Connections are provided to allow the full segregation of two cargoes in various tank combinations. Connections also allow procedures such as “series” or “cascade” purging to be undertaken. The cargo heater and booster pumps may be used for activities relating to the discharge of refrigerated product to other types of storage facility.
  • Cargo Tanks - The cargo system comprises three main cargo tanks, plus a single deck tank. All the tanks are of the independent type “C” cylindrical type design, with the two large tanks being of a ‘bi-lobe’ combined cylindrical design. The bi-lobe tanks are equipped with a solid centre line bulkhead separating the port and stbd sides of the tank in the liquid phase, but common in the vapour phase. The main cargo tanks are each located within a separate “hold” or “void” space. Whilst not normally inerted they are maintained in a dry condition using dry air. 
  • Reliquefaction system - of the cascade type having an open cycle working with cargo as refrigerant and a closed cycle working with R404A. The compressors for cargo and refrigerant, as well as heat exchangers and vessels, are separated from the electrical motors by a bulkhead equipped with gastight bulkhead penetration. The cascade part is provided for fully refrigerated service for ethene, ethane and commercial propane. The reliquefaction plant is designed for use as a seawater cooled direct mode system for use with most cargoes and in a Ethylene/R404A cascade mode cooling cycle for Ethylene cargos. It is of a 2 stage LPG/R404A cascade / direct type.
  • Ballast System - The model is equipped with a fully segregated ballast system.  The ballast pumping system comprises two, electric driven, centrifugal pumps each with a capacity of 180 m3/hr at 0.3Mpa head.  There is one stripping eductor provided with a capacity of 35 m3/h at 0.15Mpa head.

The model incorporates all the systems associated with the cargo and those required for its operation.This allows the simulation of all the operations that are likely to be conducted on this type of vessel.