【作者】

Toni Stojcevski

【摘要】

该论文已在赫尔辛基举行的第28届CIMAC大会上发表，论文的版权归CIMAC所有。The regulations as well as expectations on shipping concerning the environmental impact have been growing in recent years. At present, regulations on sulphur content in marine fuels are implemented in certain regions and a global decrease will be applied in the years to come. This has led to a search for very low sulphur (<0.1%) or sulphurfree alternative fuels. The maritime fuel of today being heavy fuel oil has often up to 4% sulphur, which requires exhaust gas cleaning systems to avoid excessive sulphur emissions. Consequently and on request from Stena Line, Wärtsilä initiated a project to select a sulphur-free fuel to be used initially on Stena ships in 2015. The fuel chosen is a liquid state methanol. The capability of methanol to replace fuels based on mineral oil has been known for a long time. In this context, methanol has been forwarded as a strong alternative that can be used in converted diesel engines. Besides the total sulphur reduction, methanol is also contributing to emission reduction, in terms of nitrogen oxides and particulates, and provides a fuel that is biodegradable, decreasing environmental impact from accidental spills. There are also demands that shipping should contribute to reducing carbon dioxide emissions radically in the future. Also here, methanol could play an important role if produced from non-fossil feedstock like CO2 capture or wooden mass. The physical and chemical properties of methanol make it very well suited for use in spark-ignited engines. It has excellent ignition properties with an Octane number of 106. But its ability to combust without forming soot (due to the lack of carbon-to-carbon bonds) has attracted diesel engine designers to find ways of using it as well. The challenges for the design of the fuel injection system are connected to the properties of methanol, in particular the combination of high viscosity of 0.57cSt at 40°C and a low boiling point of 65°C in atmospheric pressure. Then the fuel system has to be resized to accommodate the lower energy values around 19.8 MJ/kg. Eventually, the cost of methanol should be lower than that of marine gas oil, making it a competitive commercial alternative. This paper describes the patented injection system working principles and its key design challenges, the first laboratory engine results, as well as the results from the application on the first ever ship operated on methanol, the passenger ferry Stena Germanica, leading the technology development and leaving a positive trace on the society.

【会议名称】

第28届CIMAC会议

【会议地点】

芬兰 赫尔辛基

【下载次数】

3

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