Keywords

natural gas; hydrodynamics; drilling; spills; chemical discharges; dredging

Location

Session B3: Integrated Hydrodynamic, Hydrological, Water Quality, and Ecological Models

Start Date

18-6-2014 9:00 AM

End Date

18-6-2014 10:20 AM

Description

Natural gas is a premium fuel for both its energy value and environmental friendliness. Worldwide reliance on natural gas and continual discovery of new reserves around the world has spurred increased exploration and production. Offshore liquefied natural gas (LNG) developments of a large scale are being operated an built across the world requiring continual assessment of environmental impacts from operational and accidental releases. Physical and chemical environmental impacts on surface waters from these releases should preferably be assessed using a comprehensive modelling approach. In a comprehensive modelling approach, a single model is used to develop the ambient hydrodynamic conditions and to determine the fate and transport of all possible releases. This approach allows for sharing of model inputs and requires only one confirmation exercise for the hydrodynamic model that underlies the subsequent modelling of constituents of concern. Additionally, releases that can affect the ambient hydrodynamics by influencing the near-field flow characteristics through momentum or density variation can be implemented cumulatively. After the hydrodynamic model has been set up, computed flow fields are used to assess the transport and fate of the constituents of concern in the surrounding surface waters. In this paper, GEMSS (Generalized Environmental Modelling System for Surfacewaters), a fully 3-D hydrodynamic and water quality model is applied to two LNG facilities that have various operational releases requiring cumulative assessment of environmental impacts. Additionally, the paper discusses the overarching appeal of this approach by discussing, briefly, other applications such as to evaluate discharges of construction-phase dredged material, process cooling water, drill cuttings, produced formation water, accidental hydrocarbon spills, wastewater effluents, chlorine used for biofouling control, chemical effluents, nutrients, desalination brine, changes in current patterns due to construction of port facilities (dikes and jetties), due to changes in bathymetry (dredged channels), and due to the presence of anchored vessels. It was found, during the various case studies discussed in the paper, that the comprehensive modelling framework should be the preferred approach as it significantly reduces computational effort while maintaining consistency throughout the entire study.

 
Jun 18th, 9:00 AM Jun 18th, 10:20 AM

Implementation of Integrated Modelling Approach to Impact Assessment Applications for LNG Operations using 3-D Comprehensive Modelling Framework

Session B3: Integrated Hydrodynamic, Hydrological, Water Quality, and Ecological Models

Natural gas is a premium fuel for both its energy value and environmental friendliness. Worldwide reliance on natural gas and continual discovery of new reserves around the world has spurred increased exploration and production. Offshore liquefied natural gas (LNG) developments of a large scale are being operated an built across the world requiring continual assessment of environmental impacts from operational and accidental releases. Physical and chemical environmental impacts on surface waters from these releases should preferably be assessed using a comprehensive modelling approach. In a comprehensive modelling approach, a single model is used to develop the ambient hydrodynamic conditions and to determine the fate and transport of all possible releases. This approach allows for sharing of model inputs and requires only one confirmation exercise for the hydrodynamic model that underlies the subsequent modelling of constituents of concern. Additionally, releases that can affect the ambient hydrodynamics by influencing the near-field flow characteristics through momentum or density variation can be implemented cumulatively. After the hydrodynamic model has been set up, computed flow fields are used to assess the transport and fate of the constituents of concern in the surrounding surface waters. In this paper, GEMSS (Generalized Environmental Modelling System for Surfacewaters), a fully 3-D hydrodynamic and water quality model is applied to two LNG facilities that have various operational releases requiring cumulative assessment of environmental impacts. Additionally, the paper discusses the overarching appeal of this approach by discussing, briefly, other applications such as to evaluate discharges of construction-phase dredged material, process cooling water, drill cuttings, produced formation water, accidental hydrocarbon spills, wastewater effluents, chlorine used for biofouling control, chemical effluents, nutrients, desalination brine, changes in current patterns due to construction of port facilities (dikes and jetties), due to changes in bathymetry (dredged channels), and due to the presence of anchored vessels. It was found, during the various case studies discussed in the paper, that the comprehensive modelling framework should be the preferred approach as it significantly reduces computational effort while maintaining consistency throughout the entire study.