Flow Meters Provide LNG “Boil Off” Solution

Posted by Eric Haun
Thursday, January 16, 2014
Image: Allison Engineering

Level and flow instrumentation suppliers Allison Engineering have enjoyed success with a specialist flow meter application for their ST110 Gas Flow Meters being used on board LNG ships to measure boil-off gas, the natural wastage gas generated in the storage tanks. As the demand for Liquefied Natural Gas (LNG) has grown significantly in recent years so has the need for increased transportation capacity. Subsequent expansion of trade has resulted in a large expansion of tanker fleets where today LNG ships are typically carrying up to 266,000 m3 and sailing worldwide.

To facilitate transportation, the process involves natural gas being cooled down to minus 163ºC at atmospheric pressure, at which point the gas condenses to a liquid ready for transportation via tankers. The tanks on board an LNG carrier effectively function as giant thermoses in order to keep the liquid gas cold during storage. However, no insulation is perfect and the liquid is often boiling during the voyage and the solution is for reliquefaction and boil-off.

Typically LNG tankers are powered by steam turbines with boilers which are dual-fuel so they can run on either methane or oil, or a combination of both and conveniently the boil-off gas which is produced is diverted to the boilers and used as fuel for the vessel. However, where low emission zones exist, especially within European Union waters, it is mandatory for tanker operators to accurately measure how much boil-off gas they are using in their engines, as part of MARPOL Annex Vl, the current marine propulsion regulations.

Accurate and reliable measurement and specifically, in-line calibration and verification of boil-off gas, is crucial to tanker operators helping them to comply with current regulations.

The ST110 is unique in its ability to be functionally tested and calibrated without the need to remove the sensor from the pipeline. It features an internal purge tube that runs the length of the sensor and allows the operator to generate a known flow across the sensor element. The resultant signal output can then be compared to the factory baseline test certificate.

The ST110 flow meter is ATEX certified and complies with the ETS phase ll requirements for carbon trading. Materials of construction is 316 stainless steel for the housing and Hastelloy C for wetted parts, with control options via 4-20mA signal, HART, Profibus PA and Fieldbus H1 as required. It can operate at process temperatures up to +450ºC and offers a turndown ratio of 1,000:1.

allison.co.uk
 

Maritime Reporter August 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

New Products

New Generation of Turbochargers Announced

MAN Diesel & Turbo has announced the development of a new turbocharger series specifically matched to the requirements of two-stroke engines. For the first time ever,

Wärtsilä Expands Propulsion Monitoring Services

Wärtsilä expanded its offering in propulsion monitoring services. The Wärtsilä Propulsion Condition Monitoring Service (PCMS), introduced to the market in 2010,

PPG Offers SIGMASHIELD 1200 Coating for Shipping

PPG Industries' protective and marine coatings business is fulfilling growing demand for "ice class" marine coatings for hull protection with SIGMASHIELD® 1200 coating.

Tanker Trends

Mideast Crude Tanker Rates Near 3-month Low

Crude oil tanker earnings on the major Middle East route fell to their lowest in nearly three months as a slowdown in business in recent days battered rate sentiment.

China Orders More MAN Dual-Fuel Units

51/60DF engines to power LNGCs MAN Diesel & Turbo has announced a further order for its MAN 51/60DF engine. After a longer period of evaluation, an international consortium,

TORM Contracts Albwardy for Diving Services

Danish product tanker carrier TORM A/S and UAE-based Albwardy Marine Engineering (AME), an Albwardy-Damen JV, have signed a Service Level Agreement for diving services in the UAE region.

Energy

Leaky Equipment, Not Fracking, Behind Tainted US Water -Study

The contamination of water supplies near U.S. shale gas fields appears to be the result of leaky cement wells and casings and not the controversial production technique of hydraulic fracturing,

Mideast Crude Tanker Rates Near 3-month Low

Crude oil tanker earnings on the major Middle East route fell to their lowest in nearly three months as a slowdown in business in recent days battered rate sentiment.

Brazil to Hold Next Oil Rights Auction in 2015

Brazil will hold the 13th round of its oil rights auctions in the first half of next year, a senior mines and energy ministry official said on Monday. Marco Antonio Martins,

LNG

China Orders More MAN Dual-Fuel Units

51/60DF engines to power LNGCs MAN Diesel & Turbo has announced a further order for its MAN 51/60DF engine. After a longer period of evaluation, an international consortium,

Poland Received Less Gas Than Requested from Gazprom

Poland's gas pipeline operator Gaz-System said the country received about 20 million cubic metres of natural gas on Friday from the eastern direction, less than

Britain Loses Europe's Gas Trading Crown to the Dutch

Britain has been topped by the Netherlands as Europe's leading natural gas trading hub this summer, ending decades of British dominance in the sector. Britain

Marine Equipment

L-3 MSI to Equip Third Quantum Class Ship

L-3 Marine Systems International (L-3 MSI) announced today that it has been awarded a contract to provide a range of navigation, lighting and communication systems

MN 100: Thordon Bearings Inc.

3225 Mainway Burlington, State ON Canada L9C5J8 Tel: (905) 335-1440   Email: craigc@thordonbearings.com  Website: www.thordonbearings.com President

MN 100: Twin Disc, Inc.

1328 Racine Street Racine, WI 53403 Telephone: 262 638 4000 Web: www.twindisc.com President and CEO: John H. Batten Number of employees: 990 The Company: Twin Disc designs,

Maritime Safety

MN 100: Tradesmen International

9760 Shepard Rd Macedonia, OH  44056 Telephone: 800 573 0850 E-mail: ed.rojeck@tradesmeninternational.com Website: www.tradesmeninternational.com CEO/President: Joseph O.

700 Migrants Feared Drowned in Mediterranean

More than 700 people fleeing Africa and the Middle East may have drowned in shipwrecks in the Mediterranean over the last week, bringing the death toll this year to almost 3,

Maritime Reporter @ 75: The Daily Cartoon

Maritime Reporter & Engineering News was founded by John J. O'Malley (1905-1980) in 1939, and today ranks as the world's largest audited trade publication in the world serving the maritime industry,

 
 
Maritime Careers / Shipboard Positions Maritime Contracts Naval Architecture Offshore Oil Pipelines Pod Propulsion Salvage Ship Electronics Ship Repair Ship Simulators
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.1971 sec (5 req/sec)