Mass flow metering in bunkering

Mass flow metering in bunkering is set for important legal changes from 1 of January 2017 reports Luc Verley.
Mass flow metering in bunkering is set for important legal changes from 1 of January 2017 reports Luc Verley.

Article by Luc Verley MIIMS

During the Singapore Bunkering Symposium held on 8 of April 2014 the Singapore Minister of Transport Mr. Lui Tuck Yew announced that the use of a (Mass Flow Metering) system will become mandatory for marine fuel deliveries from 1 of January 2017. Therefore all existing bunker tankers operating with a Singapore harbour craft license must be equipped before 31 of December 2016 with an MPA (Maritime Port Authority of Singapore) approved Mass Flow Metering system. All new bunker tankers applying for a harbour craft licence after 31 of December 2014 must be equipped with an approved Mass Flow Metering system.

Singapore being the world’s leading bunker port in terms of volume, with over 40 million tonnes of marine fuels sold annually, takes a key step forward towards improving transparency, accuracy and efficiency of bunker supplies and will become the first port in the world to mandate the use of Mass Flow Metering for marine bunkering. The first commercial transaction with the use of a Mass Flow Metering took place in Singapore in June 2012. Currently, 17 Singapore bunker tankers are equipped with Mass Flow Metering systems and are part of a test program of MPA.

Singapore also announced the opening of research lab and test facility to set the standards for Mass Flow Metering in bunker deliveries. This facility is a co-operation between National Metrology Centre (NMC) and a local firm called Mogas. On a global level, the standards are set by OIML (International Organization of Legal Metrology), Singapore is an observing member of OIML.

As a result of high bunker costs, fuel is 50 to 70% of the operational cost of a vessel (depending on the vessels type). Indicative prices for marine fuels (based on mid-April 2014 Singapore prices): HFO380 (Heavy Fuel Oil 380 centistokes) 588 USD / ton, IFO180 (Intermediate Fuel Oil 180 centistokes) 604 USD / ton, MDO (Marine Diesel Oil) 925 USD / ton and MGO (Marine Gas Oil) 935 USD / ton.

Because of the many factors that are influencing the bunker quantity: temperature, density, low viscosity (MDO and MGO) and very high viscosity products (IFO and HFO) and flow changes during the operation (empty piping system at the start and stop and formation of air, so-called cappuccino effect), it is a complex process with lots of options for an error on the total quantity (intentional or unintentional), even a small error in the total quantity can cost an owner huge amounts of money. For example a 1% difference on the total quantity of a 3.000 tonnes bunker supply of HFO380 fuel costs 17.640 USD! Measuring accurately is of prime importance the bunker industry. The current methodology for determining the quantity of received bunkers exists out of an old- fashioned process of dipping tanks, measuring temperatures and making calculations (bunkers are sold in mass but measured in volume). Often, independent bunker surveyors are engaged to carry out a bunker quantity survey on behave of the vessels owner.

Even with the appointment of a bunker quantity surveyor the discussion over the received bunker volumes often result in very big disputes between supplier and receiver of the bunkers. Also several un-ethical practices have been taking place.

With the introduction of Mass Flow Metering bunker volume determination should be as simple as taking fuel for your car; the received quantity can be read from a meter.

However, the measurement is a bit more complex than the fuel delivery for your car in a filling station. Mass Flow Metering is based on the Coriolis flow meter theory.

A coriolos meter exist out of flow tubes and a series of sensors, in the meter the force is measured that vibrates the flow tubes, this vibration and the deflection caused is converted into a mass flow measurement. Furthermore, the temperature and density is measured. Out of this combination of measurements a volumetric flow is calculated.

The accuracy of a Mass Flow Metering system is +/- 0,5%. The biggest advantage of the Mass Flow Metering system is that the measurement is done directly in mass, no volume conversion required.

Installation of a Mass Flow Metering system on a bunker tanker costs all inclusive around 300.000 USD. The Singapore government is helping the industry by offsetting part of the cost. Currently, the systems of 2 manufacturers (Emerson Process Management and Endress + Hauser) are approved by MPA for use in Singapore.

Some major shipping companies such as Maersk and Evergreen are installing Mass Flow Metering systems on the bunker receiving line of their vessels to check received bunker quantities. The Mass Flow Metering system on a bunker tanker works in both directions for receiving and delivering bunkers. The system onboard of receiving vessels is only working in one direction for receipt of bunkers.

Mass Flow Metering is a new technology that will enable bunkering operations to be more transparent.
Useful websites:
• Websites of MPA approved manufacturers for bunker fuel mass flow metering systems:
The Endress+Hauser Group
Emerson Process Management

• Website of MPA Maritime and Port Authority of Singapore

• YouTube video explaining the Coriolis Flow Measuring Principle:

Latest Tweets from the IIMS