Improvement of Sensor Technology for Monitoring Vocs in Harbour and Maritime Areas: Use Case and first Findings

Abstract

Fugitive emissions of Volatile Organic Compounds (VOCs) resulting from industrial sources (e.g. storage tanks, gas pipelines or exhausted areas) are often sources of great concerns due to the release of unpleasant odors, irrespective if there is, or is not, a potential health impact (Manes et al., 2011). In this regard, trends of total VOCs are useful to detect the release of organic substances into the atmosphere for correlating them with potential odor harassments. Sensors based on photoionization principle have been successfully tested for continuous monitoring of the volatile organic compounds in ambient air: at the fence of productive plants; close to industrial factories or urban settlements (Locke et al., 1965). PID sensor is already proofed (University of Bari) for providing accurate data with detectable levels in the order of ppb, even in presence of high humidity conditions (Di Gilio et al., 2018). The aim of this study was the test of an innovative sensor technology (NetPID, Lab Service Analytica) capable of operating in hard weather conditions such as maritime environment, where equipment is exposed to high levels of moisture and condensate marine aerosols (droplet, not solubilized particles) (ref. MiniPID manual). The experimental design required the implementation of several PID detectors, placed on boats for dynamic monitoring of volatile organic compounds in an industrial harbour (Tsow et al., 2009). Electronic compensation for suppressing the non-specific contribution of moisture has been improved on these sensors: this led to a sensitivity below the ppb. In addition, flow chambers have been engineered and developed. Sensors have been also integrated on the dedicated smart network platform for collecting real-time data and trends with high resolution. Thanks to the data given by NetPID by the IoT platform, managers were so able to compare them with periodic information on port activities (storage, unloading, handling of raw and refined products). The setting of specific routines, based on the matching of multiple information levels (Port activities, total VOCs concentrations, weather conditions) (Choi et al., 2009), allowed to adopt the necessary corrective procedures for the mitigation of the impact of fugitive emissions in surrounded areas. Long-term tests have shown a high stability of instrumental responses, high robustness and reliability (Amodio et al., 2013).