基于多通道分布式VOCs在线监测质谱系统精准识别企业污染源

Accurate Identification of Pollution Sources in a Chemical Enterprise Based on a Distributed Multi-channel VOCs Online Monitoring Mass Spectrometry System

建立一套适用于工业园区VOCs无组织排放的监管溯源系统,该系统通过多通道分布式质谱在企业内部和厂界进行多个在线监测点位连续监测,实现对VOCs的无组织排放污染源的初步识别.监测数据结合正交矩阵因子分解(PMF)模型和二元条件概率函数(CBPF)方法精准识别园区内不同范围尺度的污染源.该系统成功应用于台州市化工园区内某医药化工厂,并对于该厂区10个监测点位进行了为期3个多月VOCs在线监测,运用PMF模型解析厂区环境大气VOCs的污染源因子,再结合CBPF方法识别各个污染源因子的地理位置信息.结果表明,在监测期间氯苯排放的贡献率和预警次数远大于其他物种,相对于其他物种,丁烯的异常排放频率更高,甲苯的异常排放频率较低;在浓度排名前10的物种中,只有氯苯在不同监测点位中有明显的浓度变化;园区环境空气中VOCs来自于丁烯排放、甲苯排放、氯苯排放、溶剂使用、涉硫工艺和工业生产;基于各污染源因子相对于10个监测点位的CBPF结果区分了厂区的本地污染源和外部污染源,并识别出了本地污染源的具体位置和外部污染源的传输方向.

A monitoring and traceability management system for unorganized emissions of volatile organic compounds(VOCs)in industrial parks has been established.This system uses distributed multi-channel mass spectrometry to continuously monitor multiple online monitoring points within the enterprise and the factory boundary to initially identify the source of unorganized emissions of VOCs.Based on online monitoring data,the system combined a positive matrix factorization(PMF)model and conditional bivariate probability function(CBPF)methods to accurately identify pollution sources of different scales in the park.The system was successfully applied to a pharmaceutical chemical factory in Taizhou Chemical Industry Park,and VOCs online monitoring was carried out for more than three months at 10 monitoring sites in the factory area.The sources of VOCs were analyzed using the PMF model,and the geographical location information of each pollution source factor was identified by the CBPF method.During the monitoring period,the contribution of chlorobenzene emissions and the number of early warnings were much higher than those of other species.Compared with that of other species,the frequency of abnormal emissions of butene was higher,and the frequency of abnormal emissions of toluene was lower.Among the top ten species,only chlorobenzene had significant concentration changes in different monitoring sites.Ambient VOCs in the plant mainly came from six sources:butene emission,toluene emission,chlorobenzene emission,solvent use,sulfur-related processes,and industrial production.Based on the CBPF results of each pollution source factor relative to the ten monitoring stations,the local pollution source and external pollution source in the plant were distinguished,and the specific location of the local pollution source and the transmission direction of the external pollution source were identified.