The temporal trend of antifouling substances in aquatic environment has been clarified by measurement of the organotin compounds in water, sediment, and biological samples. The concentrations of tributyltin (TBT) compounds in water and mussels decreased dramatically after regulation, and no changes of TBT concentrations were then observed. TBTs in fish also decreased moderately, Whereas no changes of TBTs were observed in sediment. Although triphenyltin (TPT) compounds in water, sediment, and biological samples decreased after regulation, TPTs were still detected in fish. The partition coefficients of organotin compounds for water and sediment or biological samples ranged from 103 to 105. The concentrations of Sea-Nine 211, Diuron, Irgarol 1051, pyrithions, and M1 were measured in an aquatic environment for 2 years. Higher concentrations of Diuron and Irgarol 1051 occurred in the summer season. The concentrations of Sea-Nine 211, Diuron, and Irgarol 1051 in sediment increased during the observation period. The partition coefficients of Sea-Nine 211, Diuron and Irgarol 1051 for water and sediment ranged of 102-103.
All kinds of machine tools and plants such as marine vessels, airplanes, vehicles, power stations, and chemical factories incorporate hydraulic and fluid machinery, including fluid pressure vessels, heat exchangers, compressors, and pumps using many pipelines. If abnormal pressure, corrosion, or other damage causes fluid to leak from just one part of these components, the entire machine system usually stops, and restoration of normal functions for whole plants becomes very difficult. Not only do such accidental fluid leaks in machinery and plants cause machine systems to function poorly or stop working entirely, but they can also start fires or explosions that cause immeasurable damage to company activities and society. For example, radiation leaking from a nuclear reactor or oil leaking from a tanker can directly cause air pollution and health problems, and can secondarily damage fishing grounds, agriculture, and even sightseeing. Depending on the situation, such accidents may also raise international diplomatic problems. We therefore need early detection and treatment of fluid leaks. By logical extension, we also need high reliability in the detection technologies for these plants and fluid machinery. This article outlines, explores, and considers the roles, classification, principles of detection, construction, characteristics, and related aspects of systems for detecting abnormalities and fluid leaks in machinery and plants.
This paper deals with a new electronically controlled marine two-stroke diesel engine and TES (Thermal Efficiency System) tuning applicable to future marine carriers. Demand for prime movers for marine applications centers on the following four points: 1. Compliance with future more-stringent emission regulations; 2. Increase of Engine Output for large, high-speed vessels; 3. High thermal efficiency; 4. High reliability and safety. As the best way of meeting this market demand, we propose application of the Mitsui-MAN B&W Electronically Controlled Diesel Engine with TES tuning. The Thermal Efficiency System is a diesel engine combined with a Turbo Generator and Turbo Compound System to increase the total thermal efficiency of the ship. The Thermal Efficiency System is an essential technique for reducing CO2 emission levels of ships.
In recent years, offshore plants such as FPSO, passenger vessels, and high speed ferries designed for huge capacities have been increasingly equipped with larger distribution systems with 11-KV rating. The shipping industry faces ever-greater challenges, especially regarding larger electrical distribution system, including diesel-electrical propulsion system used in 200Km3-class LNG carriers and 12, 000 TEU-class container vessels. Ship's Owners are consequently focusing more and more on higher fuel efficiency and less environmental risk. Additionally, requirements for maneuverability, reliability, redundancy, and long maintenance intervals are gradually becoming stricter.
This paper describes our investigations of the effects of split injection on the combustion and emission characteristics of a D.I. Diesel engine with a common-rail injection system. The ratio of amount of fuel injected between two consecutive injection pulses was varied while the total injection period was kept constant. As compared with single injection, having an injection period shorter than that of split injection, the split injection showed lower NOxand higher smoke emissions and inferior brake specific fuel consumption (BSFC) . Increasing the ratio of amount of the first injection improves BSFC, while maintaining the reduction in NOxemissions from single injection. Test results indicate a possibility that split injection could reduce NOx emissions without an increase in BSFC and with only a slight increase in smoke emissions.
Investigation in wind tunnel tests of the aerodynamic characteristics of a hybrid sail, consisting of a slat, a hard sail, and a soft sail was combined with experimental clarification of the interactive effects of plural hybrid sails on deck. We measured the hydrodynamic characteristics of underwater fins for advanced sail-assisted ships in tank tests, and analyzed their effectiveness on steady sailing performance, as well as investigating through wind tests the aerodynamic characteristics of a new hybrid sail that utilizes a deck crane as its boom. The weather routing system we developed for advanced sail-assisted ships showed in calculations for a North Pacific Ocean route that an advanced sail-assisted bulk carrier can cut emission of carbon dioxide by a total of 17.4 percent on the average, compared with a conventional bulk carrier.