LNG’s strong growth reveals need for standard cargo interfaces

ESD systems

While technologies such as cryogenic hoses are an important consideration, Trelleborg Marine Systems technical director Andrew Stafford said shipowners and operators need to make a number of considerations when specifying ESD systems. He pointed out that gas carriers and gas-fuelled vessels are built to comply with IMO standards and classification rules during construction.

“Both IGC and IGF up the minimum required systems outlined with relevant industry support bodies such as SIGTTO and SGMF, providing best guidance of how to implement the required safety systems and how to supplement the rules that further safety recommendations and guidance,” said Mr Stafford. By contrast, he said, “shore terminal systems have developed globally in a piecemeal fashion.”

More recently, Mr Stafford noted the ISO 28460:2010 standard was helping to ensure that new shore systems are providing the same interface as other facilities. “Compatibility with the fleet is enhanced,” he said, “but some of the older terminals still sit outside of the framework.”

His hope was that these terminals would be upgraded to the published standard interfaces during their lifetime extensions.

One important variable that needs to be considered to ensure the terminals and vessels are correctly equipped are trading patterns, said Mr Stafford. “During construction, a minimum specification can be applied. However, in practice, the installed equipment may not be suitable for the intended purpose,” he said.

One example he cited was the trading patterns of LNG bunker vessels. “They may be required to load from a traditional large-scale facility, then have to discharge that cargo as a bunker fuel to LNG-fuelled vessels, in effect, becoming a terminal to the gas-fuelled ship.” He said in that case the bunker vessel is considered a gas carrier, complying with the IGC code. “It is now connected to a vessel compliant to the IGF code, which may have different equipment arrangements compared to large-scale practice and the bunker vessel will have to accommodate these differences.”

Equally, gas-fuelled gas carriers have to make specific ESD arrangements. If you take an LNG-fuelled LPG carrier, the LPG cargo system will require its own ESD and link system to satisfy the IGC code.

Time to work together on standard cargo interface

Providing the ship operator’s perspective, Mr Heath focused on the regulations and issues surrounding the ship cargo connections.

ANSI 150 standard is often quoted as the requirement for the short distance pieces (SDPs) in the compatibility process. ANSI is the American National Standards Institute for ratings for pipe flanges, but it is not an actual standard, he said.

ASME 16.5 Standard governs the requirements of SDPs, which are short lengths of hard piping used for connection and disconnection of cargo hoses and loading arms.

“The majority of our vessels,” said Mr Heath, “which were delivered around 15 years ago, conform to the 2003 standard. This has already been superseded twice, in 2009 and 2017.” He continued, “The main thing that we have had to address through the exchanges is the surface roughness or serration of the SDPs, which I imagine a lot of vessels like ours cannot measure on board. We have been advised in the past by terminals that serration requirements have been reduced in order to prolong the seals of loading arms.”

During the compatibility process, operators and owners must ensure that there will be no issues with compatibility well before the vessel’s arrival. Many terminal manuals and confirmation lists do not give full details of the requirements, and there is also no standardisation of the confirmation lists throughout the world’s terminals.

Mr Heath said “While we are doing our best to confirm everything is in order, sometimes we have found that there has been a lack of understanding from the terminals about the SDP compatibility issue.

“While vessels are built to be compatible with numerous terminals around the world, the tendency is to only go as far as the flatbody/fender arrangements, mooring arrangements, and ship/shore link. Many vessels delivered with one standard set of SDPs find incompatibility with numerous terminals.

“For a standard 16-inch terminal cargo arm, the inner diameter, contact face diameter, flat or raised face presentation flange varies a great deal between terminals even when they are from the same arm manufacturer.”

Mr Heath posed a question to the webinar audience. “In an ever-expanding LNG market, can we not all work together to produce a standard cargo interface to improve safety, and allow vessels to call at the same terminals?”

“We have so many publications and guidance in the industry already, but there does not seem to be anything for the transfer system manufacturers to work with to have a standard connection at the manifold. Could this be something that SIGTTO or OCIMF could look at in the future?”

Floating LNG increases in complexity

Smit Lamnalco’s Andrew Brown discussed the process implications and impact of expanding floating LNG operations. Mr Brown said, “Floating LNG, side-by-side ship to ship, ship to shore, is becoming a more complex operation.” He noted onshore, offshore and nearshore variations of FLNG, FSRU, FSU, LNG carriers and STS transfers.

“We have to start looking at uniformity on how we then work with these complex operations. Location and site selection are critical to meeting the operational safety requirements,” said Mr Brown.

He also emphasised the need to educate the ‘non-LNG operation’ community. “Ports are putting FSRUs and ship to ship transfer in port. It is up to us now to start educating the ports with regards to floating LNG facilities within their boundaries and the impact it has on ports.”

“If a port has not been educated, it creates difficulty, especially if it is a commercial port,” said Mr Brown. “When we are asking shipping traffic to be shut down during a cargo transfer, the reaction from the port can be a bit negative. It is no longer about just ship to shore, the horizon has become much bigger and more challenging,” he concluded.

He then discussed some of those challenges. “You could be in a situation where you have an FSRU bunkering to a bunkering barge and also bunkering or providing LNG to a truck. We now have to start looking at these SIMOPS processes, looking at the risk assessment, these types of operations and competency levels, of course, of the operation and personnel. We are one of the safest industries in the world. We have 50 years of no incidents or loss of life, but that is because of the level of competency that we have within the industry. We now have to start looking at the rules, regulations and governance between the floating LNG and the facilities where we are working.”

A working group that was chaired by Mr Brown was supposed to launch new guidance and principles for floating LNG in April, but due to Covid-19, it has been delayed. “I am hoping this time next year, that those guidance and principles will be out there to the wider audience, where we can start bringing the non-LNG people into our way of thinking,” said Mr Brown.

In concluding the webinar, Mr Stafford, said, “We are still in a situation where we cannot say, this ship is guaranteed to be able to go to this terminal. There is still work to be done on this compatibility issue. The endgame of this industry is safe transfer anywhere in the world with any ship.”

Mr Brown said it was up to industry to educate the non-LNG community about why it is necessary to have tugs on standby for 24 hours when an LNG carrier comes to visit an FSRU, or why exclusion zones are needed.

“We have to start educating that wider audience and accepting the wider audience into our community,” he concluded.

86% expect to work with FSRUs within five years

During the ’Ship/shore interface: cargo transfer, and monitoring technology’ webinar, four audience polls were conducted. In the first poll 71% of the audience was in favour of specifying its own ESD requirements, while 29% responded they would allow a shipyard to specify based on its previous experience.

The second poll examined the audience’s experience working with FSRUs, with 46% indicating they were presently working with FSRUs, 11% expecting to work with FSRUs in one year, 18% within two years, 11% in five years and 14% not at all in the foreseeable future.

In the third poll, the audience could choose multiple options, with 68% indicating they had experience with bunkering LNG from an LNG carriers and 52% bunkering LNG from an FSRU.

The fourth and final poll asked whether the industry would benefit from more standardisation.

Some 64%of respondents said they strongly agreed, 22% agreed, while 5% indicated they disagreed and 9% said they strongly disagreed.