Making sense of LNG containment system innovations

Over the last years, dynamic market forces have generated improvements in existing and new technical solutions for LNG containment systems.

The development of floating LNG solutions – such as LNG Floating Production, Storage and Offloading (FPSO) units and Floating Storage and Regasification Units (FSRUs) – has created the need for containment systems that can manage any filling level. At the same time, the implementation of Environmental Control Areas (ECAs) has led to an increase in dual-fuel propulsion and gas-only coastal vessels, requiring smaller LNG containment tanks.

The primary goal of DNV GL is to ensure that the new containment systems coming onto the market, whether floating or land-based, are safe and effective. For companies with no experience in the maritime industry, DNV GL ensures that they have the technical support to help them manage the unique challenges of operating systems at sea. 

Approval process

DNV GL is working closely with suppliers to help guide them through the approval process for their innovative LNG containment systems. Approval is based on compliance with both the IMO’s IGF Code and the corresponding DNV GL rules. The approval process with DNV GL consists of two steps: 1. Suppliers submit designs to DNV GL to review for potential design flaws. 2. Once the designs are amended to comply with existing standards, DNV GL awards the company an Approval in Principal (AiP) certification. 

The development and the approval process often include several design iterations and therefore take time – about 18 months or more. However, in the end, owners will then have access to many different designs that match the operating profile of their vessels – from an FSRU to a coastal ferry. 

Lightweight composites 

One trend in LNG containment systems is the use of technologies and materials known from other industries such as aerospace – e.g., lightweight composites. This development has enabled the engineering of innovative tank designs that are now being further developed for the maritime industry.  The LNG segment is known for its excellent safety record. Thus, regardless of the innovative containment system, the primary goal of DNV GL is to ensure that these systems function effectively and safely, without risk to the crew, cargo or the environment. As one of the first classification societies to define rules for LNG, DNV GL is supporting suppliers and owners alike in safely managing the shift to LNG.