回转窑转速对废塑料热解产物特性的影响

Influence of Rotating Speed on Pyrolysis Products of Waste Plastics in Rotary Kiln

在外热式回转窑热解实验台上,以废塑料聚丙烯(polypropylene,PP)、聚乙烯(polyethylene,PE)为实验物料,在不同转速下对热解产物的特性进行了实验研究。实验结果表明:从提高产油率角度来讲,该实验转速以4 r/min为适宜,并且转速对PP和PE热解油的热值有一定的影响。转速对PP和PE的热解残炭的产率影响不大,转速对其热值影响比较大,在实验转速范围内PP的残炭热值最大增幅为31.5%,PE残炭的热值的最大增幅高达116.1%。PP和PE热解气的热值随转速的变化趋势与热解气中C3、C4和C5的烃类含量变化趋势相同。在一定转速范围内,增大转速有利于油的轻质化。转速对PP热解气成分的影响并不大,而转速对PE热解气中低碳成分和高碳成分的比例影响较大,在4 r/min时低碳气体成分的含量最低,高碳气体成分的含量最高。

The research was conducted on the externally heated rotary kiln to study the impact of rotating speed on the pyrolysis products of waste plastics. The typical constituents of waste plastics such as polypropylene （PP） and polyethylene （PE） were selected as the testing materials. The results show that the rotating speed should be set at 4r/min to enhance the productive rate of pyrolytic oil and the heat value of pyrolytic oil is influenced by the rotating speed to some extent. The impact on the productive rate of pyrolytic carbon is far below the pyrolytic carbon＇s heat value, the maximum increase of heat value of PP＇s carbon can reach at 31.5%, and PE is 116.1%. The changing trend of pyrolytic gas＇s heat value is the same as the content of C3, C4, and C5. In a certain speed range, heavy oil can be converted into light oil by increasing rotating speed. The composition of PP＇s pyrolytic gas is not largely influenced by the speed, but it has a large influence on the low carbon component and high carbon component ratio of PE. At 4r/min, the low carbon component reaches the minimum value and the high carbon component gets to the maximum value.