酚类抗氧化剂抑制生物柴油氧化及对排放影响的试验研究

Experimental Study on Biodiesel Oxidation Inhibition and Emission Influence of Phenolic Antioxidants

针对生物柴油氧化安定性较差、NO_x排放较高的问题,选用酚类抗氧化剂如迷迭香、茶多酚和丁基羟基茴香醚,分别添加到生物柴油中,测量了生物柴油在不同氧化时间下的过氧化值。在186F柴油机台架上,燃用添加不同抗氧化剂的生物柴油,测量了标定转速、不同负荷时的NO_x和HC排放。试验结果表明:与没有添加抗氧化剂的生物柴油相比,经过4 320h后,添加迷迭香的生物柴油过氧化值最大降低了0.028mol/kg,降幅近48%,生物柴油的氧化安定性得到明显改善;与B20调和生物柴油相比,添加迷迭香、茶多酚抗氧化剂的K1B20与K2B20调和生物柴油的HC排放的平均值有小幅升高,添加丁基羟基茴香醚的BHAB20调和生物柴油的HC排放平均降幅为25%;标定转速不同负荷时,添加抗氧化剂,NO_x排放均下降,在75%负荷时,添加迷迭香的K1B20相对B20的NO_x最大降幅为9.4%。3种抗氧化剂中,迷迭香抗氧化剂对于提高生物柴油氧化安定性和降低柴油机燃烧生物柴油NO_x排放的效果最好。

In view of the poor oxidation stability and higher NO x emissions of biodiesel,three kinds of typical phenolic antioxidants including rosemary,polyphenols and butyl hydroxy anisole were added into biodiesel respectively and the peroxide values of biodiesel at different oxidation periods were measured.On the 186F diesel engine bench,biodiesel with different antioxidants was used and the NO x and HC emissions at different loads of rated speed were measured.The results showed that the peroxide value of biodiesel decreased by 0.028 mol/kg and its decrease was close to 48%after 4 320 hours by adding phenolic antioxidant and biodiesel oxidation stability improved significantly.Compared with B20 blended fuel,the average HC emission of K1B20 and K2B20 fuel with rosemary and polyphenols increased slightly.The average HC emission of BHAB20 with butyl hydroxy anisole decreased by 26%.NO x emissions reduced after adding antioxidants under different loads at rated speed.Compared with B20,the NO x emission of K1B20 with rosemary reduced by at most 9.4%at 75%load.Among the three antioxidants,rosemary antioxidant had the best effect on improving the oxidation stability and reducing the NO x emissions of biodiesel.