石化企业挥发性有机物无组织排放监测技术进展

Current status and future developments in monitoring of fugitive VOC emissions from petroleum refining and petrochemical industry

无组织排放占石化企业挥发性有机物(VOCs)排放的主导地位,排放点多、面广、量大、分散、无规则,总体表现为大型面源或体积源,监测难度很大。本文评述了点、线和面(通量)等VOCs无组织排放监测技术及应用进展,总结了石化企业VOCs无组织排放监测存在的主要问题与难点,提出了石化企业VOCs无组织排放监测体系及适用监测技术。总体上,石化企业VOCs无组织排放监控存在排放清单质量不高、源头监测及溯源困难、排放烟羽及其迁移扩散途径无定形、厂界等开放空间难以封闭监测、常规监测的时间和空间覆盖有限等问题或技术难点,可复合应用点、线、面及通量监测技术,结合常规离线、实时在线、排放通量、移动快速响应等监测设计,构建覆盖排放与环境影响的多元化、网络化、立体化监控体系。未来石化企业VOCs无组织排放监控将向多层级、智能化和大数据应用发展。

Most of the VOC emissions from a refinery or a petrochemical plant correspond to fugitive emissions from numerous leakage points and irregular vents. These emissions are spread across the industrial sites and may vary significantly over time and space, and aggregate large area sources or large volume sources on the whole, and therefore this is rather difficult to achieve on both high spatial and temporal coverage in the monitoring. This paper reviews the present status and developments of VOC emission monitoring techniques, including point monitoring, open path monitoring, cross section monitoring and flux monitoring. It summarizes the main problems and technical difficulties in monitoring fugitive emissions of VOCs from a refinery or a petrochemical plant and also suggests a framework system and alternative supporting monitoring techniques for such emissions. In summary, the fugitive VOC emissions monitoring of a refinery or a petrochemical plant is faced with many problems and technical challenges including high uncertainty in emission inventories, difficulty to monitor and trace fugitive resources, irregularity in emission plumes migration and diffusion, impossibility to fully cover open space in monitoring fenceline emissions, limited time and space coverage in routine monitoring, etc. It is hence necessary to establish a multicomponent, three-dimensional, VOC fugitive emission monitoring system to cover the emission and their impact on adjacent communities. It is suggested that such a system should be based on various types of new monitoring techniques(point-, open path, cross section and flux) in combination with routine monitoring(off line, real time, emission flux and mobile quick response). In future, fugitive VOC emissions monitoring of a refinery or a petrochemical plant will be developed towards multi-dimensional, multi-level, intelligent and big data applications.