城市公交车用稀土催化净化反应器的开发与试验

Development of Rare-Earth Elements Catalytic Converter for Urban Bus

采用稀土元素作催化剂、蜂窝陶瓷作载体,针对城市公交汽油车设计制造了尾气净化装置,进行了发动机的性能试验,测试了净化装置的净化转化率和消声量频率特性。结果表明,对于试验用稀土催化净化反应器,实际消声量在各个频率段上均大于必需消声量;净化转化效果明显,例如当发动机怠速运转、补氧量充足时,CO和HC的净化转化率可达90%以上;同普通消声器相比,压降稍大,从而导致发动机输出功率有所下降,燃油消耗率有所上升。

A honeycomb-like ceramic substrate catalytic converter was designed for gasoline urban buses, in which the rare earths were used as catalyst. An experiment was conducted to investigate the engine performances and examine the conversion efficiency and noise reduction quantity frequency characteristic for the catalytic converter. Experimental results show that practical frequency characteristic curve of noise reduction quantity covers completely necessary curve for this experimental catalytic converter. The conversion efficiencies for CO and HC can reach 90% when the engine runs at idling condition. Compared with the conventional muffler, the pressure drop of the catalytic converter is higher so that the power of the engine reduces slightly. If design parameters are selected reasonably, the catalytic converter has the function of noise reduction while it meets the needs of space velocity and ignition initiating temperature for purification.