Nonintrusive fast response concentration measurement device for chemical reactors

A device is proposed by which the residence time distribution in a tubular chemical reactor can be measured with a response time on the order of hundreds of microseconds. This device works on the principle of infrared laser absorption spectroscopy. Because the light beam passes directly through the reactor cross section, there is no measurement cell thus making the technique nonintrusive. The device has been successfully tested with a tubular reactor with a gaseous flow at average residence times ranging from 0.04 to 0.7 s. The level of micromixing in the reactor can also be estimated due to the very fast response of the instrument. (C) 1996 American Institute of Physics.