steam turbines temperatures being achieved.
One major benefit in the use of steam turbine plant in LNG carriers continues to be the levels of exhaust gas emissions during normal operation using boil-off gas. Carbon dioxide emissions are reduced due to the nature of the fuel and the UST plant has a further positive impact on these through its increased efficiency. As an additional benefit, NOx and SOx emissions are also low for steam turbine plants, which can a particular advantage during times spent in port and while loading and unloading the LNG cargo. The MHI UST plant turbine design has also been revised, primarily to include an intermediate pressure stage. This is integrated with the high
pressure stage, operating back to back on the same shaft, with a central inlet casing for both stages. Designs are rated for higher steam inlet temperatures of up to 560°C and new technology has been introduced to both blade and nozzle designs. Pressure at the superheater outlet is now increased to 10 barG with a boiler design rating of 12 barG. UST plants are available with outputs ranging from 23MW up to 37MW and nominal turbine shaft speed is 76 rpm for a 25MW rated installation. As a result of these improvements, MHI claims that UST plant performance is improved by 15-20 per cent compared with its earlier, conventional steam turbine (CST) designs. For the initial HHI order for the Petronas
LNG carriers, MHI will provide four complete UST plants, with each vessel being equipped with two boilers and a single steam turbine propulsion package. The first plant delivery to HHI is planned for 2015 with Petronas receiving its first new vessel in 2016. Each double-hulled carrier will be fitted with four independent self-supporting spherical tanks which provide good performance during loading and unloading operations, having lower tendencies to exhibit sloshing forces compared with membrane tank system. This makes the design preferable for operation in rough seas conditions. The total value of the order is reported by HHI as being worth $850 million. HHI claims that it is the only Korean shipbuilder able to currently build Moss-type LNG carriers and has delivered 15 vessels from its Ulsan shipyard since 1994. Following the signing of the contract with Petronas, Ka Sam-Hyun, executive vice president of HHI’s shipbuilding division, was optimistic about future orders and the significance of pressure on emissions. “We see this order as the first of many for LNG carriers as regulations for carbon dioxide emission tighten and demand for LNG increases as an alternative energy source,” he said. With further potential orders in sight, these new vessels are also a clear indication that PETRONAS is moving further into direct involvement in the LNG marketplace.
Cylmate® Sensors. Pressure under control.
Save money by tuning and controlling the combustion pressure stroke-by-stroke. Cylmate pressure sensors used on electronically controlled diesel engines enabling improved energy efficiency and lower the risk for off-hire costs. The unique and reliable Cylmate pressure sensor has
proven its maintenance- and calibration-free performance during years of continuous operation. 5 year warranty.
www.abb.com/pressductor
Kawasaki offers steam turbine and diesel options
Kawasaki Heavy Industries (KHI) has become a major player in building LNG carriers, delivering its first steam turbine driven vessel, the Golar Spirit in 1976. Three decades later, in 2006, KHI announced the completion of its 100th marine steam turbine for installation in a 145,000m3 capacity vessel, 24 of which had been delivered during the previous financial year ending March 2006.
They have all been fitted with its own steam turbines, which have a history going back to 1907 when it manufactured its first marine turbines under a technical alliance with the USA’s Curtis Company. When the agreement lapsed in 1925, it began developing its own designs.
technology,
ABB AB Force Measurement Phone: +46 21 32 50 00
42 I Marine Propulsion I April/May 2014
Despite being a leader in steam turbine however, KHI
has also seized
opportunities to provide LNG carriers with alternative propulsion systems. In October last year, for example, it delivered the 2,500m3 domestic LNG carrier Kakuyumaru, which is powered by
www.mpropulsion.com
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108