PVTx Properties of a Two-phase CO2 Jet from Ruptured Pipeline

Span and Wagner equation of state (SW EOS) have been used to investigate changes in the thermodynamic properties of CO2 during a depressurization process from a pipeline into marine environment. The process is assumed to be isenthalpic, as only the thermodynamic change at the moment of depressurization is considered. The calculations show that the depth location of the pipeline influences greatly the density, temperature and volume changes, because of the difference in the surrounding pressures. In general the two-phase area is reached at depths shallower than 600 meters, which yields for the Norwegian Continental Shelf, as it is mainly shallower than 500 meters depth. There is a rapid decrease in density in the two-phase area causing a rapid expansion in the volume of CO2 from 4 MPa to 1 MPa. At the shallowest depth considered (100m) the volume fraction consist almost entirely of gas, and the density change give a significant increase in volume.publishedVersio

The development of oxygen content in the Greenland Sea from 1993 to 2008. A study of convection depth and deep layer changes.

In previous years the hydrography in the Greenland Sea have been investigated based on temperature and salinity observations along with different transient tracers. In this work annual zonal sections, averaged values of the central parts of the Greenland Sea and the deep layer changes have been investigated to provide a fuller view of the changes and trends in the Greenland Sea over most of the 1990s and 2000s. The main parameter is the oxygen concentration that has been used together with temperature and salinity. Earlier it has been stated that the increase in temperature and salinity is due to the inflow of Arctic Ocean Deep Water in the form of Canadian Basin Deep Water and Eurasian Basin Deep Water, and reduced convection compensating for the increase of these parameters. Investigation of the oxygen concentration has provided another argument to support this theory where the decreasing trend in oxygen along with the increasing trend in temperature and salinity indicate the inflow of a warmer, more saline water mass of older age than the Greenland Sea Deep Water

PVTx Properties of a Two-phase CO2 Jet from Ruptured Pipeline

Span and Wagner equation of state (SW EOS) have been used to investigate changes in the thermodynamic properties of CO2 during a depressurization process from a pipeline into marine environment. The process is assumed to be isenthalpic, as only the thermodynamic change at the moment of depressurization is considered. The calculations show that the depth location of the pipeline influences greatly the density, temperature and volume changes, because of the difference in the surrounding pressures. In general the two-phase area is reached at depths shallower than 600 meters, which yields for the Norwegian Continental Shelf, as it is mainly shallower than 500 meters depth. There is a rapid decrease in density in the two-phase area causing a rapid expansion in the volume of CO2 from 4 MPa to 1 MPa. At the shallowest depth considered (100m) the volume fraction consist almost entirely of gas, and the density change give a significant increase in volume

The effect of submarine CO2vents on seawater: Implications for detection of subsea carbon sequestration leakage

The effect of submarine carbon dioxide (CO2) vents on seawater carbonate chemistry have been determined using hydrographical and marine carbonate data obtained from two submarine hydrothermal vent fields, as well as a reference station, all near the Jan Mayen Island in the Norwegian-Greenland Sea. We have shown that one can successfully determine the excess carbon that enters the seawater from the vents by applying a modified version of a back-calculation technique, which is traditionally used to study the invasion of excess atmospheric CO2 in the surface ocean. As a result of this excess carbon, total dissolved inorganic carbon (CT) in the seawater surrounding the vents was on average 12 μmol kg−1 (1-30 μmol kg−1) higher compared to samples obtained from a reference station outside the venting areas. The observed excess CT was most significant between 100 m and 200 m but was noticeable in all depths with the exception of the upper 10-20 m. The absence of a venting CO2 signal in the surface water and the realism of the results are discussed. We believe the present method is promising for monitoring (detection and quantification) of CO2 leakage into the water column due to its high sensitivity and readiness for automation