Newly Developed Combined EGR & WEF System to comply with IMO NOx Regulation Tier 3 for Two-stroke Diesel Engine
IMO NOx emission regulation Tier 3 will come into force from 2016 and require the marine two-stroke diesel engines to reduce their emission below a cycle value of 3.4 g/kWh in Emission Control Area. To cope with this regulation, the combined EGR (exhaust gas recirculation)&WEF (water emulsified fuel) system, aiming at effective NOx reduction with the minimum penalty in fuel oil consumption, has been newly developed and provided for the fullscaled test engine Kawasaki-MAN B&W 2S50ME-C. EGR applied is so-called ’high pressured EGR’ featuring compactness in components. Turbocharger cutout system and VT (variable turbine nozzle area) turbocharger are incorporated in EGR system, which enables it to reduce NOx with only a minimal impact on fuel oil consumption, and to switch on/off depending on the sea area. Wet scrubber is also incorporated in EGR system to remove SOx and PM in the recirculating gas, which prevents corrosion and contamination in the scavenging air system during EGR. Detection and control methods for water carry-over has been newly established and tested. Water treatment system is one of the most important systems for EGR and has been developed to remove PM in the washing water out of the scrubber. A special compact settling tank with unique ditches has been developed based on the sewerage treatment technologies and secures the efficient removal of PM. This paper describes 1) the characteristics of EGR system, such as relations between EGR ratio and NOx emission, EGR ratio and fuel oil consumption, etc. both on newly developed EGR system with turbocharger cut-out system and VT and on conventional EGR system without them, 2) the performance of scrubber including water carryover and 3) the capability of water treatment system. And then 4) the result of the combined EGR & WEF system measured on test engine is reported in comparison with EGR alone. In addition to the test results by the test engine, this paper describes outline of our original ’package type EGR system’ for on-board test. The package EGR system that major components of EGR are equipped on the main engine is introduced to facilitate the installation of the system in the ship. On the other hand, WEF technique is preceding EGR and now provided for long term operation in order to accumulate experiences in service field. The latest condition is reported additionally.
Masanori Higashida Takuroh Nakamura Ikumi Onishi Katsuhiro Yoshizawa Hirotaka Takata Takamichi Hosono
Kawasaki Heavy Industries,Ltd.,Japan
国际会议
上海
英文
1-12
2013-05-13（万方平台首次上网日期，不代表论文的发表时间）