Cavity-Enhanced Gas Analyzer for Process Control Applications

70149S02-II In the production of polymer-grade ethylene, petrochemical manufacturers must actively minimize the amount of acetylene contamination to less than 10 parts-per-million. Process control engineers must respond quickly to prevent the contamination of stored ethylene and irreversible damage to catalytic beds. Currently, gas chromatography is used to provide this industrial process control; however, this technology is both slow (minutes) and expensive. This project will develop an industrial process control monitor for acetylene in ethylene gas flows. The technology will provide an absolute, accurate measurement of acetylene contamination fifty times faster than and at one-third the cost of conventional methods. Phase I built and tested a compact, rugged version of a patented Off-Axis Integrated Cavity Output Spectroscopy (ICOS) gas analyzer and demonstrated its ability to accurately measure acetylene in ethylene gas flow mixtures to better than 100 parts-per-billion in one second. System parameters were thoroughly investigated and long-term stability was demonstrated. Phase II will integrate a refined Off-Axis ICOS industrial process control system into an analyzer package and test the working instrument in an ethylene manufacturing plant. A multiplexed prototype analyzer will be produced to simultaneously measure a variety of other impurities (e.g. CO, CO2, H2O, NH3, propyne) in ethylene process flows. Commercial Applications and Other Benefits as described by awardee: The industrial process control analyzer should have direct commercial application within the petrochemical manufacturing community. In addition, the ultrasensitive gas analyzer also should find use in environmental monitoring, medical breath-diagnostics, and vehicle emissions testing, providing a potential market of $50M.