Feature 4
ions (O
2
). At the same time, a gaseous fuel is greatest potential for use with SOFCs, as NOx reduction can also be gained
fed to the anode side of the fuel cell. The fuel methanol especially is suited to marine by applying common rail technology,
has to be in a form that can be utilised by the applications, due to its liquid form. However, due to its humidity without visible
cell; therefore any fuel has to be converted there are a number of other options, smoke. Smokeless operation is said to
into hydrogen and carbon monoxide, either including diesel, landfill gas, coal bed occur at all loads and in all operational
inside or outside the fuel cell. methane and waste gases, ethanol and other sequences. Common rail is thought to
The oxygen ions formed at the cathode alcohols, as well as biogases formed during provide increased flexibility in engine
migrate by ionic transport through the the gasification and fermentation processes. optimisation and improved combustion
electrolyte to the anode, where they combine control, plus improved total fuel economy
with hydrogen and carbon monoxide, emission reduction and the flexibility to use different fuels
oxidising the hydrogen into water, and the But bold plans to develop fuel cell technol- without hardware modifications.
carbon monoxide into carbon dioxide. ogy are just one area of development. Wärt- Other projects which have been
During the oxidation, two electrons are silä has also been involved with ventures to undertaken by Wärtsilä include the
released to set up an electric current, and reduce emissions of existing common fuel research of electo-hydraulically operated
these electrons are transferred to the cathode types. gas exchange valves of diesel engines,
through an external electric circuit. NOx emission reductions have been and two-stage turbocharging to further
The SOFCs can have different physical sought by utilising ‘wet’ means: direct reduce emissions.
shapes, the most common being either water injection (DWI), humidification, or Scrubbing technology has also been
planar or tubular. The operation temperature water-fuel emulsions technologies. This tested, intended to remove sulphur
is usually in the range of 650°C-1000°C, Wetpac evaluation had to take into account oxides from exhaust gases. A programme
which means that the heat can be used in a specific fuel oil consumption trade off, initiated in 2006 is aimed at investigating
various applications. but results suggested that the potential for the effect of scrubber design on engine
Wärtsilä plans to introduce WFC50 NOx reduction is as follows: up to a 20% performance, lifetime and economy,
units in the 50kW range for commercial reduction using water-fuel emulsions, with ecological impact, the risk of acid rain
demonstration within a couple of years, a 0.3% water to fuel ratio; a 40% reduction droplets, and white smoke. The results
looking into pre-commercial niche uses using humidification, but with a 1.3% water should be equally applicable to any
thereafter. to fuel ratio; and a 50% reduction utilising two stroke or four stroke engine, and
Natural gas and methanol are the fuels DWI, with just over 0.6% water to fuel also to both newbuildings and retrofit
currently being focused on as having the ratio. installations. NA
significant ships of 2007
AvAIlAblE IN PRINTED OR cD-ROM FORMAT
PRE-PublIcATION OFFER
A publication of
The Royal Institution of Naval Architects
The Royal Institution of Naval Architects will publish the 18th edition of
its annual Significant Ships series in February 2008. Produced in our
usual technically-orientated style, Significant Ships of 2007 will present
approximately 50 of the most innovative and important commercial
designs delivered during the year by shipyards worldwide. Emphasis
will be placed on newbuildings over 100m in length, although some
significant smaller cargo ships, fast ferries and offshore vessels will be
considered, including a cross-section of ship types, with each
vessel being either representative of its type or singularly
significant. Each ship presentation will comprise of a
concise technical description, extensive tabular principal
Newbuildings nominated:
particulars including major equipment suppliers, detailed general
arrangement plans and a colour ship photograph.
Tembek, Fram, Orange Trident, Star, Deo
Volente, Yacht Express, Natchan Rera, Histria
Non-member £37 (RINA member £32)
Amber, Dubai Star, Hoegh Delhi, British
Or Order a set:
Emerald,
One copy of Significant Ships 2007
plus many more
& one copy of Significant Small Ships 2007
price £49 (RINA member £42)
When ordering please advise if printed or cD ROM format is required, contact :
The Marketing Department,
RINA, 10 Upper Belgrave Street, London, SW1X 8BQ, UK. Tel:+44 (0)20 7235 4622 Fax +44 (0)20 7259 5912
E-mail:
publications@rina.org.uk Website:
www.rina.org.uk
The Naval Architect January 2008 89
NA Jan - p88+
89.indd 89 07/01/2008 12:29:16
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