Will the use of mass flow metering during bunker deliveries catch on?
19th October 2010 04:19 GMT

The disclosure of results from flow meter trials, conducted by the Maritime and Port Authority of Singapore (MPA) and Singapore standards agency, Spring Singapore, will be one of the highlights at the 16th Singapore International Bunkering Conference and Exhibition (SIBCON 2010).

The results of the trials, and the potential endorsement by the MPA, could influence bunkering operations for shipowners, bunker suppliers and oil terminals alike.

Several stakeholders have given positive feedback on flow meters, highlighting benefits the technology brings to the industry.

Seah Khen Hee, chairman of the Technical Committee for Bunkering, Spring Singapore, told Bunkerworld that flow meters provide "increased productivity and efficiency" for bunkering operations.

The use of mass flow meters, also known as Coriolis flow meter or Inertial flow meter, could help increase Singapore's bunkering capacity by one-and-a-half to two times, allowing faster turnaround and shorter port stays for ships while reducing administrative processes and costs, he said.

Flow meters provide a very high level of accuracy in determining the quantity of bunkers delivered and faulty calculations caused by entrained air, for example, are minimised.

Joshua Low Chin Chuan, regional head of Maersk Oil Trading, another promoter of flow meter use, said that the measurement device brings new levels of "transparency and efficiency" for bunkering operations.

Low acknowledged the high cost of flow meters, which would be passed down to clients and consumers, but he believed any business doing a cost benefit analysis would find justifications for using the technology.

"For Maersk the two main factors [are] transparency and efficiency, which are two very strong economic justifications," said Low.

Another representative of Maersk Oil Trading, Business Development Manager Rosenkrans Ødum claimed that efficiency gains from time-saving were "generating excitement in all corners of the industry".

"Suppliers have recognised the flow meter's ability to level the playing field and to provide the sort of transparency the industry has been seeking for years," said Ødum.

"A number of suppliers have been keen to get engaged in the process and are eager to stay on top of the development rather than being left behind as the industry progresses."

He said Maersk was likely to favour suppliers "who have embraced this new technology" and that those who failed to do so would place themselves in a disadvantageous position.

Questions raised

Optimism about the implementation of flow metering technology for bunkering operations is not shared by all members of the marine community.

A prominent industry player in Singapore told Bunkerworld that flow meters present several problems with regards to calibration and tank stripping.

"From what I know, there is no way of calibrating the flow meter onboard a vessel," said the player, who claims to have seen flow meters in action.

"The flow meters are as tall as a door and look like they weigh several tons. I would need to engage a floating crane to have these flow meters calibrated onshore.

"And what will I do with my bunker barge when the flow meter is being calibrated?" he said, adding that revenues will be lost in the event of onshore calibration due to operational downtime.

Another concern raised is the accuracy of fuel measurement by the flow meter being compromised by entrained air during bunkering operations in the process known to the industry as "tank stripping".

Legal implications

Frequent calibration of flow meters is an important factor, especially in the event of a dispute.

"In an event of bunker dispute, the first question the judge will ask is 'when was your flow meter last calibrated?'" the player said, adding that he believes judges will react negatively to a supplier who has not calibrated his flow meter.

"What will the judge say if I told him that the flow metering unit was last calibrated five years ago, the time when I bought the unit? And that the company which I bought the flow meter from said that no calibration is required?"

Taking the above into consideration, Bunkerworld asks: Will the use of mass flow metering during bunker deliveries catch on?

This story has been amended as of 11:40 GMT on October 20, 2010.

Will the use of mass flow metering during bunker deliveries catch on?

  • 23% 
  • 29% 
  • 48% 

This poll is now closed.


Comments on this Article
Tommy Christensen - Go4 Bunker ApS (CBI)
21st October 2010
Bunker suppliers are regulated by their home port authority. Any flow meters on barges could be audited, regularly proved and certified by the port authority. But they have no control over the flowmeters fitted to vessels and no way of being able to assure that the flow meter is correctly installed and calibrated and that there are no “magic pipe” bypasses. Far better to regulate flow measurement on the barges and to prioritize the barge flow measurement.
Incidentally, a conventional coriolis meter and a conventional density meter will readily show when there is entrained air from the signal disruption. The EGA density meter can only allow you to infer entrained air from the density measured.
With instrumentation (including coriolis meters) to detect air, the options are to fix any operational or equipment problems causing entrained air or for the vessel to reject any bunker with air in it. If most cappuccino events are fraud then detection and rejection will fix that problem straight away - Tommy Christensen / Go4 Bunker (Denmark)
Thomas Marian - Buffalo Marine Service Inc
27th October 2010
Buffalo Marine Service has had three coriolis meters installed on its blending tank barge (BUFFALO STAR) since 1993. Since that time, there has not been a single shortage claim and the meter readings have always synched up with the tank gaugings. The manufacturer of these meters (Micromotion) informed Buffalo Marine that during the course of operation these meters would not require calibration. In fact, out of an over abundence of caution, Buffalo Marine sent the meters back to the manufacturer in 2003 when the blending barge was undergoing its decennial overhaul and drydocking to comply with U.S. Coast Guard regulations and Buffalo Marine's preventive maintenance program. The manufacturer indicated that the meter ground-truthing was unnecessary but bench tested them at our insistence. The meters were well within accuracy tolerances and returned to Buffalo Marine for re-installation on the blending barge.
Over time, given U.S. Coast Guard regulatory requirements, Buffalo Marine began installing mechanical meters on its fleet of 30,000 Barrel (4000 MT) bunker barges. The mechanical meters were installed with air eliminators, robust internal strainers and required calibration. As these meters also contained temperature compensation devices, the net barrel readings were consistent with the dip gauge validations; however, the mechanical nature of these devices required close monitoring to ensure that inaccuracies were not unfolding during the course of multiple jobs. Ultimately, in 2009, Buffalo Marine devised a system to install coriolos meters on its bunker barges employing an independent power source from the pushboat (Note that the vast majority of bunker jobs performed in the united States are from non-self propelled tank barges being pushed by tows). There were several appealing aspects to this system:

1) No need for calibration given the dearth of moving parts and ability of the manufacturer to remotely query the meter's performance data;
2) Less deck space required due to no air elimination system;
3) Elimination of strainer system; and
4) An independent wheelhouse monitoring system which allowed the Captain to oversee the bunker delivery rates.

With respect to the last-enumerated advantage, Buffalo Marine opted for the Fueltrax program which captured four independent data streams on a real time basis: mass flow rate; volume flow rate; temperature and density. In one case that unfolded last year, a Chief Engineer claimed a shortage until he was shown the density and temperature charts at which point he withdrew his claim. Regardless of his rationale for such a claim, the density graph has been very effective in assessing the homogeneity of the fluid (e.g., bunkers) passing through the meter. This was recently driven home when a discrepancy emerged between a net barrel figure and a mass amount recorded by the meter. The net barrels were tied to the supplier's API. This number is manually entered into the Fueltrax program in order to convert the gross barrel figure to a net barrel amount. Yet, it was discovered that back-to-back loads from the same terminal shore tank with identical APIs and nearly identical temperatures had markedly different density readings. Thus, the metric tons measured were more precise than the net barrel conversion amount. This was validated against the gross barrel amount remaining aboard the tank barge using the mean temperature recorded by the meter (Note that the snap shots of the fluid's properties by the coriolos meter on a second-by-second basis provided a more accurate temperature than the tankerman's tank-by-tank temperature readings).
At the end of the day, density certainly does not provide a user with the precise composition of the fluid or any contaminants that lurk therein but it will provide you with an extremely accurate mass figure which, in turn, generates an equally accurate gross barrel amount. This has proven to be the case with or without air entrainment or if the product's API has been adversely impacted by shoreside tank stratification. Indeed, the mass flow meter has enhanced Buffalo Marine's delivery performance via markedly fewer shortage claims, more robust documentation of the properties of the bunkers delivered and ability to reliably provide multiple deliveries from one barge.
Ara Barsamian
29th October 2010
The modern Coriolis massmeter (2008-2010) is vastly superior to conventional methods of measurement for custody transfer:

1) It is highly accurate and precise, compared with PD meters, turbines, or tank gauging plus strapping tables
2) Can measure two phase flows
3) Measures simultaneously mass, density, temperature, and viscosity
4) Can be easily checked using portable provers (you don't need to remove it and ship it to the factory)
5) Is practically indestructible and ultra-reliable

I have been using Coriolis massmeters since 1990 with excellent results for bunker, diesel, and gasoline blending, and custody transfer. I installed them in 3rd world countries where they worked in utter neglect...

The people that oppose its use are generally not familiar with them, are scared by the price (instead of looking at the life-cycle cost vs. cost of bunker per year), or are afraid that the high accuracy when used for custody transfer will deprive them of "flexibility" of measurements in their favor...

Generally I install 2 Coriolis massmeters, one on the delivery barge/marine terminal, and one on the vessel receiving the bunker.
Tan Chin Tian - Golden Island Diesel Oil Trading Pte Ltd
23rd November 2010
If oil terminals, bunker barges and vessels are to install with the same type of flow meter, that will show new levels of transparency and effciency for the shipowners, oil terminal and barge operators.

Comments have been closed for this article.

Post your Comments on this Article

Please sign in by clicking here to post comments.

Not registered? Click here and register for FREE.