摘要：
考察了4个不同平滑度(0,1,3,5)的光谱预处理对拉曼光谱测量结果的影响,并优选平滑度为1的预处理方法.考察了最小二乘拟合基底及Ar基底两种不同基底扣除方法对拉曼光谱测量结果的影响,并优选Ar基底扣除方法,定期校正更新Ar基底.在原有混合标准气体CH4,C2H4,C2H6,C3H6,C3H8,H2 6组分交叉干扰定量分析的基础上,增加1,3-丁二烯、正丁烯和异丁烯3种组分对以上6个目标组分计量峰干扰值的扣除,但分析精度没有明显提高.探讨了乙烯裂解气中C2H6误差较大、C3H8未检出的原因.实验结果表明,要提高激光拉曼气体分析仪的测量精度,在改进计算方法的同时,更多地需要从硬件入手,通过改进光路结构增强试样的拉曼信号,以最终达到提高仪器测量精度的目的.%Six major components(CH4,C2H4,C2H6,C3H6,C3H8,H2) in pyrolysis gas were analyzed by means of laser Raman spectrometry. The effects of spectral pretreatment with four different smoothnesses(0,1,3,5) on the Raman analysis results were investigated and the pretreatment with smoothness 1 was the optimal. The influences of two baseline methods,namely the least squares fitting baseline and the Ar baseline,on the Raman analysis results were researched,and the Ar baseline method was better. Based on the quantitative analysis of the cross interference of the 6 target components,the interferences of 3 additional components including 1,3-butadiene,butane and isobutene were deducted,which did not led to the significant improvement of the Raman analysis accuracy. The reasons of the poor analysis for C2H6 and C3H8 were discussed. It was indicated that in order to improve the measurement accuracy of the laser Raman gas analyzer,improving hardware may be more important than modifying algorithm.
