Application of Standardized Quality Control Procedures to Open-Path Fourier Transform Infrared Data Collected at a Concentrated Swine Production Facility

Abstract

Open-path Fourier transform infrared (OP/FT-IR) spectrometry was used to measure the concentrations of ammonia, methane, and other atmospheric gases at a concentrated swine production facility. A total of 2200 OP/FT-IR spectra were acquired along nine different monitoring paths during an 8-day period between January 11 and 22, 1999. Standardized quality control (QC) procedures were applied to the archived OP/FT-IR spectra to verify that the instrument was set up and operating properly during the field study and to identify outliers in the concentration data. These QC procedures included measuring the random baseline noise, the signal strength, and the relative single-beam intensity in selected wavenumber regions; inspecting the archived spectra for wavenumber shifts, changes in resolution, and evidence of detector saturation; and examining time series plots of the target gas concentrations and the uncertainty values reported by the classical least-squares (CLS) analysis. Application of these QC procedures to the archived spectra identified 252 potential outliers. After a careful review of the original spectra, 41 of the 252 suspected outliers were designated as actual outliers. Of the QC criteria used during this study, the uncertainty values reported by the CLS analysis were the most reliable indicators of actual outliers.

Source Identification of VOCs in a Petrochemical Complex by Applying Open-Path Fourier Transform Infrared Spectrometry

“…In contrast, open-path Fourier transform infrared (FTIR) spectrometry has the advantages of being adaptable, transportable, capable of remotely monitoring several different paths in real time, and carrying out multi-compound analysis. This approach has thus been widely applied for air pollutant monitoring and odor source identification at large-area sources, such as semiconductor manufacturing plants (Tsao et al, 2011), swine production facilities (Childers et al, 2001;Aneja et al, 2008), coke ovens (Lin et al, 2007), petrochemical plants (David et al, 1994;Webb et al, 1996), and urban areas (Hong et al, 2004). Several studies also showed that the concentrations of target compounds obtained by OPFTIR are comparable to those determined by conventional methods (Childers et al, 2001).…”

Advances in optical methods for trace gas analysis

“…FT-IR measurements have become routine and automated systems are successfully providing time-sequenced, pathaveraged emission data from agricultural operations, landfills, industrial facilities, and other large-area vapor emission sources [6]. Current research efforts promise exciting new capabilities that address some of the limitations.…”

Open‐PathFourier Transform Infrared Spectroscopy

“…Gronauer et al 69 used OP/FT-IR spectroscopy to measure ammonia, methane, nitrous oxide, and carbon dioxide downwind from an openair composting windrow and during slurry spreading operations on grasslands. Childers et al 75 measured the concentrations of these same gases along several monitoring paths throughout a concentrated swine production facility. Eklund and LaCosse 70 used OP/FT-IR spectroscopy to monitor emissions downwind from beef processing plants and a chicken processing plant.…”