Thermal and Biological Impact of LNG Vaporizer Discharge

A simplified steady state multilayered (horizontally homogeneous) thermal model is described and applied to assess the effects of the cold water discharge created by a proposed liquid natural gas (LNG) regasification facility. The model, similar to ones developed for predicting average cooling pond performance, accounts for advection and diffusion between layers, atmospheric and solid boundary heat exchange, and heat exchange due to tidal and density currents. For the configuration in which both the intake and discharge were located in a dredged turning and docking basin, recirculation created thermal deficits from -8°C to -17°C. Adverse environmental effects on migrating species (particularly various life stages of shrimp) and the benthic community and costs associated with auxiliary seawater heating suggested that other alternatives (such as a separate intake basin or an offshore diffuser) would be more appropriate.