The demand for countermeasures to global warming continues to increase throughout the world. The long-term prospects of energy supply have been reported inside and outside Japan during the period from 2004 to 2005. The two reports both present a similar outlook that petroleum energy will still be the dominant source of energy in 2030. The future trend of petroleum energy use in the transport sector is considered the key to stabilize the supply and demand of energy. With respect to marine fuel oil, developments in global environmental regulations are expected to greatly affect the demand-supply trend and quality of the international commodity. This paper analyzes such trends that provide a basis for addressing the issues of energy demand and supply and future quality of energy.
Recently, it is increasingly common that ships are built electrically controlled engines and installed with remote-control equipment. The effect of electromagnetic waves and interference may cause any of these systems to malfunction. Similar worries address to the effects on living organisms, an area where practical, real-world research is needed. Because trends indicate that more high-performance electronic devices will be installed on ships in the future, research into electromagnetic compatibility is becoming increasingly important to guarantee shipboard safety. It is vital to grapple with the problem of electromagnetic environments in the same way demanded by air pollution and water pollution. This paper examines electromagnetic-compatibility regulations and countermeasures for engine-control devices abroad ships.
Marine fuel oil differs from fuel oils for automobiles and energy-saving plants especially in its properties. As a low-grade fuel oil, it is not only mainly composed of hydrocarbon but also contains a great quantity of sulfur, nitrogen and residual carbon contents. PM components formed by reaction of combustion have not been thoroughly examined. As sea transportation increases, it becomes necessary to grasp the present state of PMs exhausted from vessels as an air-pollutant and it needs to take a research and development to reduce them. Accordingly, relevant organizations including International Maritime Organization (IMO) continue to consider regulations. This study is intended to check a temperature of the flame to raise by burning Marine Diesel Oil (C heavy oil) and Emulsion Fuel oil in a boiler, also measured the concentration of DS and SOF after collecting the PM (Particulate Matters) . Especially, SOF are analyzed by using high performance liquid chromatography (HPLC) . The additive used in our experiment is inorganic matter that causes of non hazardous. At any tempemture (15-100°C), that is not harmful and makes the oil and water not separate. The water emulsion diameter is about 30μm. The reaction of combustion was promoted by Emulsion and the concentration of the PAHs got low with NO, CO2, SO2, DS, SOF.
Dimethyl Ether (DME) was mixed with waste vegetable oil to improve combustion and exhaust emissions in a high speed diesel engine. Past research has shown that the properties of DME, such as lower boiling point and higher cetane number, would affect atomization process and combustion progress of DME/Marine diesel oil blending fuel. In this study, the effect of mixing DME with waste vegetable oil was investigated by using the 4-stroke single cylinder direct injection diesel engine. The combustion pressure history, injection pressure, exhaust gas emissions were measured in variation with mixing ratio of DME and engine load. The emissions of smoke and nitrogen oxide were found to reduce with increase in mixing ratio of DME.
In this study, surplus of high temperatures and low temperatures waste heat from two engine systems during voyage on board training ship, Shioji-maru and Seiun-maru, were measured. Based on measured values, the reductions of CO2 as GHG (Green House Gas) emission were estimated. In the case of effective utilization of waste heat energy performed by air-conditioning, cold storage, and other appliances, effects of each parameter on COP (Coefficient of Performance) of absorption refrigerator were showed. The following results were obtained: (1) for an application of a single-effect absorption refrigeration system to the Sioji-maru, CO2 can be reduced at about maximum of 9% and refrigerating capacity can be expected at about 350 kW from the measured data, (2) for an application of a single-effect absorption refrigeration system to the Seiun-maru with distilled water plant at 50% working rate, CO2 can be reduced at about maximum of 11.5% and refrigerating capacity can be expected at about 430 kW. Also CO2 can be reduced at about maximum of 21.5% and refrigerating capacity can be expected at about 825 kW for an application of a double-effect absorption refrigeration system to the Seiun-maru with used steam of 50%, (3) application of variable seawater temperature, used temperature, and difference concentration of liquid solution to double-effect absorption refrigeration system showed smaller effect for reduction of CO2 than applied to the single-effect one, (4) the COP and reduction of CO2 increased at low seawater temperature and high used temperature, and those also increased when applied a great difference concentration of liquid solution.
Agreement of exhaust air pollution and substances from ships included in MARPOL Treaty (73/78) Annex VI of IMO Air Pollution Control, has been enforced since 19 May 2005. Ships by more than 130 kW class of diesel engine that sail within 200 nautical miles from the coast may cause the serious problems of pollution. It is necessary to develop a new control system for the pollutants emitted from the ships. In this study, a scrubber equipment was developed to reduce the pollutants of NOx and Particulate Matters (PM) in the exhaust tube. The equipment has three stage scrubbers that spray seawater, acid and alkaline water were generated by electrolysis of seawater. NO changes nitrocyl chloride (NOCl) with Cl2 in the acid water. This resulted 73% of reduction rate of NO. However, the reduction rate of NO and PM are 14.3% and 70% respectively at exhaust gas flow of 570 l/min.
The velocity and pressure fields of a ship's Weis-Fogh type propulsion mechanism is discussed in this paper using the advanced vortex method. The wing of the NACA0010 and the channel are approximated by a finite number of source and vortex panels, and the free vortices are introduced from the body surfaces. The viscous diffusion of fluid is represented using the core-spreading model to the discrete vortices. The velocity is calculated on the basis of the generalized Biot-Savart law and the pressure field is calculated from an integral based on the instantaneous velocity and vorticity distribution in the flow field. Two-dimensional unsteady viscous flows of this propulsion mechanism are numerically clarified. The calculated results agree well with the experimental results.
The leakage of fluids from pipe flange connection is the most critical problem for the safe operation of power and chemical plants. It is well known that such leakage is likely to occur in the case of fluids under high or low temperature. The tightening operation of pipe flange connection is usually conducted under room temperature. The temperature of pipe flange connections starts to increase when the plant is in operation. Then, the difference in thermal expansion between bolt-nut connection and fastened plates causes significant changes in bolt force, which might lead to the leakage of the contained fluid. This phenomenon is largely influenced by the complex non-linear behaviors of gaskets. This study has experimentally examined how the bolt clamping forces of pipe flange connections vary under high temperature. Two types of commonly used gaskets made of asbestos and aramid have been used in the experiments. It has been found that the bolt forces significantly decrease with the progress of the heating operation, and the reduction of bolt forces is remarkably observed with increase of gasket thickness. Bolt clamping forces of pipe flange connections under high temperature are reduced to less than 70% and as much as 70 % of the initial values, in the cases of thick asbestos and aramid gaskets, respectively.