Optics: measuring and testing – By dispersed light spectroscopy – With sample excitation
Patent
1995-10-06
1997-09-23
Hantis, K.
Optics: measuring and testing
By dispersed light spectroscopy
With sample excitation
333 99PL, G01J 330, H01P 100, G01N 2169
Patent
active
056710453
ABSTRACT:
Microwave-induced plasma for continuous, real time trace element monitoring under harsh and variable conditions. The sensor includes a source of high power microwave energy and a shorted waveguide made of a microwave conductive, high temperature capability refractory material communicating with the source of the microwave energy to generate a plasma. The high power waveguide is constructed to be robust in a hot, hostile environment. It includes an aperture for the passage of gases to be analyzed and a spectrometer is connected to receive light from the plasma. Provision is made for real time in situ calibration. The spectrometer disperses the light, which is then analyzed by a computer. The sensor is capable of making continuous, real time quantitative measurements of desired elements, such as the heavy metals lead and mercury. The invention may be incorporated into a high temperature process device and implemented in situ for example, such as with a DC graphite electrode plasma arc furnace. The invention further provides a system for the elemental analysis of process streams by removing particulate and/or droplet samples therefrom and entraining such samples in the gas flow which passes through the plasma flame. Introduction of and entraining samples in the gas flow may be facilitated by a suction pump, regulating gas flow, gravity or combinations thereof.
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Cohn Daniel R.
Surma Jeffrey E.
Titus Charles H.
Woskov Paul P.
Hantis K.
Masachusetts Institute of Technology
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