船用低速柴油机SCR系统的设计优化与试验分析

Design optimization and test analysis of SCR system on marine slow speed diesel engine

由于船舶机舱空间狭小,因此布置用于二冲程柴油机的SCR反应器和其管道较为困难。利用CFD模拟了在100%负荷下SCR反应器之前的尿素雾滴和排气的混合过程。模拟结果表明,当6S35ME-B9 SCR系统的旋转角和护盖展开角分别为15°和75°时,尿素与排气在较短的距离内能够形成良好的混合,并且整个系统压降小于1.4 kPa。对安装有SCR系统的6S35ME-B9柴油机进行了100 h的测试,结果表明NOx排放从18.15 g/kWh降低到3.17 g/kWh。针对6S35ME-B9柴油机的SCR系统的设计和试验可以为实船上的SCR系统提供理论和应用基础。

Due to the narrow space of ship engine room,the arrangement of the two stroke diesel engine SCR(UreaSCR, Urea, Selective, Catalytic, Reduction) reactor and its pipe is difficult. CFD was used to simulate the mixing process of urea droplets and smoke exhaust in the front straight mixing section of a SCR reactor under 100% load. Finally, when the rotation angle and shroud expansion angle of 6S35ME-B9 SCR system were 15 degrees and 75 degrees, reducer forms a well mixing with the exhaust gas in a short distance and the whole system pressure drop is less than 1400 Pa. Through the full scale SCR system, the 6S35ME-B9 engine is tested for 100 hours, and NOx emissions were reduced from 18.15 g/kWh to 3.17 g/kWh. The design of the full scale SCR system of 6S35ME-B9 marine diesel engine and bench test, it provides the theory and application foundation for the real ship SCR system.