Hydrodynamic and Advection-Dispersion Simulation of Cool Seawater Discharges from an LNG Facility

The impact of cool seawater discharge in the coastal waters from a Liquefied Natural Gas (LNG) plant has been simulated using MIKE21. In this work, hydrodynamics conditions of the coastal waters were calibrated and corroborated to predict the cool seawater discharge under two plant design scenarios by selecting flow rate 15 m(3)/s and 10 m(3)/s with a temperature drop of 5 degrees C and 7 degrees C, respectively. The simulations were carried out under different scenarios, to arrive at the best possible case to minimize the potential impact on the coastal environment. Both the simulated scenarios complied with the available World Bank guidelines for LNG facilities. However, the designed scenario of flow rate 10 m(3)/s with a temperature drop of 7 degrees C between inlet and outlet presents a better choice as it reduces the pumping power of seawater intake. As there are no Indian guidelines for cool seawater discharges from LNG plant, the present work can support the policymakers and regulators to formulate coherent discharge standards.