A Theoretical Study of the Applicability of Open-path FTIR for Benzene Fenceline Air Monitoring
Abstract
Benzene is a carcinogenic compound that is the byproduct of a number of anthropogenic sources. It is a natural part of crude oil and gasoline, as well as a number of industrial processes. In the United States it ranks in the top 20 chemicals for production volume. The Office of Environmental Health Hazard Assessment (OEHHA) recommends that that background concentration of benzene be kept below 0.9 ppb to prevent long-term chronic effects in affected populations.
Starting in 2020, the South Coast Air Quality Management District's (SCAQMD) Rule 1180 requires all major petroleum refineries in the South Coast Basin (SCAB) to install and operate fenceline air quality monitoring systems to monitor selected criteria pollutants and air toxics, including benzene, along the boundaries of the refineries. In this presentation we explore the detection of benzene from open-path optical remote sensing systems which use Infrared Fourier Transform Spectroscopy (OP-FTIR). Benzene spectral retrievals for a number of absorption bands in the infrared were simulated using the radiative transfer model GFIT (developed at Jet Propulsion Laboratory and used for over 30 years for a variety of FTIR applications), and detection limits were calculated. We simulate benzene retrievals with realistic errors, but also explore the theoretical "best detection limit" possible with current spectrometers. We also evaluate the influence of a number of environmental factors that are likely to influence benzene retrievals, such as the presence of water vapor and methane, and the spectral resolution of FTIR instruments. Finally, we will also discuss the feasibility of using FTIR systems for fenceline benzene observations compared to the Open Path UV DOAS.- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.A11I2667P
- Keywords:
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- 0345 Pollution: urban and regional;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0368 Troposphere: constituent transport and chemistry;
- ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 3307 Boundary layer processes;
- ATMOSPHERIC PROCESSES;
- 3360 Remote sensing;
- ATMOSPHERIC PROCESSES