The transfer operations of LNG at the port result from the interaction of three main factors:

- Vessel -

With its propulsion and steering characteristics, capacity, onboard equipment, sensitivity to environmental agents.

– Physical Environment –

Vertical and horizontal dimensions of channels and basins, meteorological and maritime conditions.

– Human Factor –

Captains and officers, pilots, tugboat captains, VTS operators.

Thus, when designing port infrastructures or establishing operational conditions, it is essential to consider these three key elements. Only by integrating these factors can an optimal level of safety and efficiency be achieved. Nowadays, advanced simulation tools facilitate an accurate assessment of these aspects.

These include dynamic models for moored ships, interaction models between vessels, traffic flow simulations, and fast-time and real-time ship maneuvering simulators.

Design of LNG (Liquified Natural Gas) Port Terminals

The design of an LNG or FSRU technology terminal must address several crucial nautical aspects, such as docks, mooring and fender equipment, channels and navigable areas, both horizontal and vertical, metocean studies, and operational procedures. This involves considering the access and mooring of design ships, as well as larger vessels, operational limits, traffic analysis, towing requirements, mooring analysis, and the effects of passing ships, among others. Additionally, LNG ship traffic demands a thorough nautical risk analysis that includes comprehensive HAZID/HAZOP processes.

Finally, it is recommended to implement training programs that include real-time simulations for pilots, captains, officers, and tugboat captains.

Tools and Methodology for Feasibility Analysis of LNG Terminal Analysis

There are several advanced software tools available to support highly accurate analyses in various areas:

– Dynamic Mooring Mathematical Models –

The software is designed to analyze the mooring conditions of a ship during loading/unloading operations and in survival conditions, where the limits of stay at the dock are evaluated. Its results provide a detailed assessment of the vessel´s movements and the forces exerted on the mooring lines and fenders under specific meteorological and maritime conditions.

This tool is mainly used for the design and optimization of moorings at maritime terminals.

– Passing-Ship Interaction –

If the terminal is in a transit channel, it is crucial to evaluate the forces and movements generated by passing ships through a narrow navigation channel, especially when one or more ships are moored.

This evaluation allows determining the loads transmitted to the terminal’s fenders and mooring elements.

– Maritime Traffic Simulation –

It is also advisable to estimate the port capacity when planning a new development to ensure compliance with design requirements: the capacity of port facilities and the expected traffic (including anchorage areas, number of tugboats, channel dimensions, among others). For this purpose, there are numerical models, such as Siflow21, that allow identifying potential bottlenecks and establishing preventive measures.

– Manoeuvring Study –

“Fast-time” and “real-time” simulators can reproduce the behaviour of a specific vessel during manoeuvers, controlled either by an autopilot or a real captain/pilot, respectively. Real-time simulation incorporates the human factor in the development of ship manoeuvers, providing more accurate and reliable results. Therefore, this modality is more suitable for detailed analysis of complex manoeuvering conditions, where the human factor, including perception and decision-making, becomes more relevant.

Nautical Risk Analysis in LNG Terminals and HAZID/HAZOP Processes

It is essential to evaluate potential risk scenarios, such as a ship grounding or collision. The consequences of these incidents can be estimated using the proposed tools and based on this, appropriate preventive or corrective measures can be established. The consequences of these incidents can be estimated using the proposed tools and based on this, appropriate preventive or corrective measures can be established. Additionally, once the navigation conditions are defined, it is crucial to analyze the possible repercussions of extraordinary events, such as propulsion or steering failures, reduced visibility, positioning errors, among others. These types of events go beyond the usual difficulties associated with navigation during normal manoeuvers.

These studies aim to identify, analyze, and evaluate various risk hypotheses during LNG and oil ship operations. Preventive or corrective measures will be established and tested, following IMO recommendations. The information obtained will be used to define restricted navigation areas and develop contingency plans.

During HAZID/HAZOP processes, all information will be coordinated among the involved parties, and clear criteria for normal and emergency terminal operations will be established.

Maritime Training in LNG Terminals

As the final step in the design process, a specific training programme can provide captains and officers with prior familiarization with new ships and navigation and manoeuvering areas, including meteorological scenarios, bathymetric characteristics, navigation aids, and other relevant aspects, as well as manoeuvering strategies. For this, it is crucial to conduct a detailed analysis of the available data in the initial stages of the study, select and model representative scenarios, and define an appropriate simulation programme that meets the project’s objectives. These courses will help improve knowledge of local conditions and manoeuvering strategies, which are usually new in most cases.

Port infrastructures are designed for a longer lifespan than vessels, requiring adaptations to accommodate larger ships, especially LNG carriers. This involves reviewing the terminal’s capacity through analyses involving multiple stakeholders, such as port authorities, operators, pilots, tugboat captains, and shipping companies.

It is crucial that all parties agree on updated operational procedures, possibly including training programmes for captains, officers, and pilots before allowing access to new vessels.