CONFINED BOILING RATES OF LIQUEFIED PETROLEUM GAS ON WATER

Results of a program to measure the rate of boiling of liquefied petroleum gas (LPG) on water surface and to develop an analytical model to describe the phenomena involved are reported. Primary emphasis was placed on liquid propane or LPG mixtures containing small quantities of ethane or butane or both. A few exploratory tests were, however, made with pure liquid ethane, ethylene, and n-butane. The investigation was conducted to provide quantitative data and analytical models to delineate the rate of vaporization, the spread rate and the degree of fractionation, should an LPG tanker suffer an accident leading to a major spill on water. For propane or LPG spills on water, immediately following the contact, violent boiling commenced. Ice quickly formed; in most cases, ice was even thrown onto the sidewalls of the vessel. In some instances sprays of water/ice and propane were ejected from the calorimeter. Within a few seconds, however, the interaction quieted and the surface was covered by a rough ice sheet. The LPG boiled on the surface of this ice, but large gas bubbles occasionally appeared under the ice shield and were trapped. The boiling rate decreased with time with a concomitant increase in the thickness of the ice shield. In the first second or two, very high boiling heat fluxes were experienced. The mass of LPG lost was approximately half that spilled originally. It is estimated that only 5 to 15% could have been ejected as liquid if the water loss is used as a reference. However, since the water surface is very agitated during this period, it is not possible to obtain reliable quantitative values of the boiling flux. Also, as noted, the mass lost in the very early time period was approximately proportional to the original mass of LPG used. It may be inferred that larger spills lead to more mixing and boiling before the ice shield prevents a direct contact between the LPG and the water. (ERA citation 03:046762)

  • Corporate Authors:

    Massachusetts Institute of Technology

    Department of Chemical Engineering
    Cambridge, MA  USA  02139

    Department of Energy

    1000 Independence Avenue, SW
    Washington, DC  USA  20585
  • Authors:
    • Reid, R C
    • SMITH, K A
  • Publication Date: 1978-5

Media Info

  • Pagination: 51 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00186444
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Contract Numbers: EE-77-S-02-4548
  • Files: TRIS
  • Created Date: Feb 27 1979 12:00AM