高原地区不同海拔下内燃叉车气态污染物排放特性研究

Emission characteristics of gaseous pollutant from internal combustion forklift at different altitudes in plateau area

为研究内燃叉车在高原地区不同海拔下的气态污染物排放特征,采用便携式排放测试系统(PEMS),分别在海拔1 550、2 350和3 100 m的3个地区,对内燃叉车污染物进行排放测试,基于测试数据,分析内燃叉车在不同工况下的污染物排放特征,计算污染物基于时间的排放量。结果表明:在不同海拔下,CO、CO_(2)和NO_(X)的瞬时排放速率在空载行走工况下最大,在热机怠速工况下相对较小;原地举升工况下,CO、CO_(2)和NO_(X)的瞬时排放速率随海拔升高而增加。随着海拔的升高,CO基于时间的排放量在热机怠速与复合作业工况下分别增加1.52~2.09倍和2.13~4.21倍,在空载行走工况下呈先上升后下降的趋势,NO_(X)基于时间的排放量在热机怠速、空载行走和复合作业工况下均呈现随海拔升高而增加的趋势,分别增加1.10~1.17倍、1.24~1.88倍和1.15~1.42倍;不同海拔下,重载行走工况CO基于时间的排放量小于空载行走工况,NO_(X)则与之相反;不同海拔下,冷机怠速工况CO和NO_(X)基于时间的排放量大于热机怠速工况。

In order to explore the emission characteristics of gaseous pollutant from internal combustion forklift at different altitudes in plateau area, a portable emission testing system(PEMS) is used to test pollutant emission from internal combustion forklift in three areas at the altitudes of 1 550,2 350 and 3 100 m respectively. Based on the test data, the pollutant emission characteristics of internal combustion forklift are analyzed under different operating conditions, and time-based pollutant emission volume is calculated. The results are as follows: At different altitudes, the instantaneous emission rates of CO,CO_(2) and NO_(X) are the highest under unladen traveling condition and relatively low under engine idling condition;the instantaneous emission rates of CO,CO_(2) and NO_(X) in the in-situ lifting condition increase with the increase of altitude. With the increase of altitude, the time-based emission rate of CO increase by 1.52~2.09 times and 2.13~4.21 times respectively under the hot engine idling condition and composite operation condition, while showing a trend of first increasing and then decreasing under unladen traveling condition.The time-based emission of NO_(X) in the hot engine idling, unladen traveling and composite operation conditions all show a trend of increasing with altitude, increasing 1.10~1.17 times, 1.24~1.88 times and 1.15~1.42 times respectively. At different altitudes, the time-based emissions of CO under heavy-duty traveling condition are lower than those under unladen traveling condition, while NO_(X) is the opposite;the time-based emissions of CO and NO_(X) under cold idling condition are greater than those under hot idling condition.