《Low sulphur fuel.doc》由会员分享，可在线阅读，更多相关《Low sulphur fuel.doc（10页珍藏版）》请在三一办公上搜索。
1、Name:Goh Choong Leoong Student No: P268477 Date: 30/08/06 TABLE OF CONTENTS 1 INTRODUCTION - 3 & 4 1.1 Pictures on the effects of acid rain - 5 1.2 Marpol Annex VI - 6 1.3 EU Directive - 6 2 MAJOR SETBACKS OR PRECAUTIONS OF USING LOW SULPHUR FUEL - 7 2.1 Price- Cost Effectiveness - 7 2.2 Incompatibi
2、lity of BN of lubricant and Sulphur content in fuel-8 2.3 Recommendation for fuel sulphur level Vs Cylinder oil BN-9 3 REFERENCES - 10 1 IntroductionThe presence of sulphur in the marine fuels contributes to the environmental pollution and other problems. As the sulphur in fuels burn, it will form S
3、Ox which is one of the pollutants to the environment especially in the formation of acid rain. Acid rain damages forests and crops (See figure 1), changes the makeup of soil, and makes lakes and streams acidic and unsuitable for fish. Continued exposure over a long time changes the natural variety o
4、f plants and animals in an ecosystem. SO2 accelerates the decay of building materials and paints, including irreplaceable monuments, statues, and sculptures that are part of our nations cultural heritage. (See figure 2&3) CaCO3 + H2O Ca(OH)2 + CO2 2 CaCO3 + 2 SO2 + O2 CaSO4 + CO2The sulphur content
5、in fuel oil has a large impact on the particle level in the exhaust gas. Tests and analysis of exhaust gas have shown that a high sulphur HFO can give several times higher particle levels than if the engine operated on gas oil. A large part of the difference between HFO and DO is related to sulphur
6、which together with water forms particulates and it is shown as follows: Apart from that, should the sulphur in fuels burn in the cylinder react with the water vapours being formed during the combustion process (whereby the combustion temperature falls within the dew point of fuel vapours), sulphuri
7、c acids will be formed and many parts of the cylinder will get corroded such as cylinder liners, exhaust valves and seats. Consequently, this will result in higher costs bear by the shipowners for maintaining operation of the ships. The conversion of sulphuric acids is shown as follows:1.1 Pictures
8、on the effects of acid rain Figure 1 Acid rain destroyed crops and plants Figure 2 Acid rain destroyed monumentsFigure 3 Acid rain destroyed national heritage 1.2 Marpol Annex VIDue to the above-mentioned problems with regard to the sulphur contents in marine fuels; IMO has come up with the regulati
9、ons for the prevention of air pollution from ships under Marpol Annex VI. Marpol Annex VI entered into force in May 2005 and the main features are as follows:I) Sulphur cap 4.5% worldwide which is equivalent to 45000 ppm II) Bunker delivery notes required III) Local supplier register IV) Statutory f
10、uel sampling1.3 EU Directive Apart from that, Marpol Annex VI has also defined SOx emission control areas (SECA) and the procedures for implementing new such areas. Presently the Baltic, the North Sea and the English Channel are affected, the main features being: Maximum permissible sulphur content
11、1.5% or equivalent to 15000 ppm Fuel changeover to be recorded in log book. All in all, the new directive of the maximum permitted sulphur content of marine fuels is as follows:2 Major setbacks or precautions of using low sulphur fuel 2.1 Price- Cost Effectiveness As the new regulations set in, most
12、 of the ships will have to use lower sulphur base fuels in order to meet the minimum requirements as to control the emissions of SOx. Nevertheless, the major setback by switching from residual fuels (IFO 380, average sulphur content: 2.7 %) to marine distillate fuels (Average sulphur content: 0.6%)
13、is the cost effectiveness. As shown in the graph 1, the cost of marine distillate fuels will be more than twice what residual fuels costs due to increasing demand and cost of desulphurization process. Graph 1 Price comparison between residual fuel (high sulphur) and marine distillated fuel (low sulp
14、hur)2.2 Incompatibility of BN of lubricant and Sulphur content in fuel Apart from using low sulphur content fuels, the formation of acids in the engine can be minimized by using cylinder lube oil contains alkaline components usually calcium salts (through neutralization). BN or TBN is a measure of c
15、ylinder lube oils ability to neutralize acids. The higher the BN, more acids can be neutralized or vice versa. Nevertheless, the BN/Fuel sulphur content must be compatible otherwise it will lead to scuffing or excessive wear in the engine. The risks involve as follows:Using low sulphur content fuel
16、and high BN There will be excessive calcium ash in BN which will deposit on the piston crown land, exhaust valves, turbocharger and combustion chamber and these deposits may become very hard and contact between the deposits and the cylinder liner wall can cause bore polishing which will accelerate t
17、he wear. Using high sulphur content fuel and low BN There might be insufficient BN to neutralize the acids being formed and this will result in corrosion. On the other hand, attempts to counteract by increase feed rate of low BN lubricant would lead to over lubrication. 2.3 Recommendation for fuel s
18、ulphur level Vs Cylinder oil BN Therefore, it is important to have a compatible BN/Fuel sulphur content in preventing the above-mentioned problems. Hence, the recommendations are as follows:Graph 2 Use of BN40 Vs BN70 cylinder oil (See graph 2)3 References:WARTSILA, Switzerland, 2006. Wartsila Low S
19、ulphur Guidelines Online. Available from: Accessed 28th August 2006. MAN B & W Diesel A/S,Copenhagen, Denmark,2002. Marine Transport Fuels and Emissions Online.Available from http:/www.umweltbundesamt.de/verkehr/downloads/seeschifffahrt/Aabofullpaper.pdf#search=low%20sulphur%20fuels%20in%20marine Ac
20、cessed 28th August 2006 MAN B & W Diesel A/S,Copenhagen, Denmark,2002.Operation on Low-Sulphur Fuels Two-Stroke EnginesOnline. Available from Accessed 28th 2006 Starcrest Consulting Group,LLC, 2003.Evaluation of Low Sulphur Marine Fuel Availability- Pacific RimOnline. Available from http:/www.portoflosangeles.org/DOC/REPORT_Fuel_Study_Pacific_Rim_Sec4.pdf#search=evaluation%20of%20low%20sulphur%20marine%20fuel%20availability Accessed 28th 2006
