Multiplexed Diode-Laser Gas Sensor System for In Situ Multispecies Emissions MeasurementsEPA Grant Number: R823933
Title: Multiplexed Diode-Laser Gas Sensor System for In Situ Multispecies Emissions Measurements
Investigators: Hanson, Ronald K. , Baer, D. S.
Institution: Stanford University
EPA Project Officer: Shapiro, Paul
Project Period: October 1, 1995 through September 30, 1996 (Extended to December 31, 1997)
Project Amount: $194,870
RFA: Exploratory Research - Engineering (1995) Recipients Lists
Research Category: Engineering and Environmental Chemistry , Land and Waste Management
The purpose of this project is to develop a multiplexed diode-laser gas sensor system capable of sensitive path-integrated emissions measurements for use in compliance monitoring and process control. The sensor system combines fiber-optic and diode-laser technology, absorption spectroscopy, and second-harmonic generation techniques to probe electronic and vibration-rotation transitions of selected species and thus enable in situ measurements of multiple species, simultaneously, at several locations. These advanced optical sensors are species-specific, insensitive to interferences, and offer prospects for remote, non-intrusive, continuous measurements of species concentration and temperature in high-temperature environments including waste incinerators, natural gas combustors, heaters, and internal combustion engines. The target species to be monitored with the first generation of the proposed sensor system include: NO2, a critical pollutant; CO, a combustion product; and CO2, a combustion product and greenhouse gas. Extension of the technique to monitor other species (e.g., NO, N2O, NH3, CH4, HF, H2O, O2 and various hydrocarbons) in combustion effluents is possible.