Share Email Print
cover

Proceedings Paper

Monitoring of O2 and temperature in a pelletizing process
Author(s): Lars G. Sandstroem; Stefan Helge Lundqvist; Torbjoern Andersson
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

We will show the results from a Tunable Diode Laser (TDL) spectrometer installation monitoring the O2 concentration and the temperature in an olivine pellet production plant. The spectrometer has been operating continuously for more than two years. In the pelletizing process a reduction of magnetite and sintering takes place at a temperature around 1250 degree(s)C. To achieve a high and predictable quality of the produced pellets the oxygen concentration and the temperature has to be measured in-situ inside the process furnace. A specially designed high temperature sensor was mounted on the furnace wall and an optical fiber was used to carry the probing light from the TDL spectrometer to the measurement point. The TDL spectrometer operates at two absorption lines in the near infrared wavelength region to measure the oxygen concentration and the temperature simultaneously. The temperature is measured using the relative intensity of the two absorption lines and the concentration is calculated from the temperature compensated absorbance. The accuracy of the concentration and temperature measurements at 1 s response time was 0.1 vol.% and 50 degree(s)C, respectively. In order to validate the TDL measurements the pelletizing process furnace temperature was varied between 100 degree(s)C up to 1300 degree(s)C while the oxygen and temperature readings from the TDL spectrometer was recorded. The temperature measurements were also correlated with temperature measurements using thermocouples inside the furnace. The O2 absorption line parameters were determined in a controlled laboratory experiment using a heated measurement path. This work shows that it is possible to build and field a TDL spectrometer to measure O2 and temperature in-situ in a steel making process furnace.

Paper Details

Date Published: 25 October 1999
PDF: 7 pages
Proc. SPIE 3758, Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II, (25 October 1999); doi: 10.1117/12.366456
Show Author Affiliations
Lars G. Sandstroem, Altoptronic AB (Sweden)
Stefan Helge Lundqvist, Altoptronic AB (Sweden)
Torbjoern Andersson, Altoptronic AB (Sweden)


Published in SPIE Proceedings Vol. 3758:
Application of Tunable Diode and Other Infrared Sources for Atmospheric Studies and Industrial Processing Monitoring II
Alan Fried, Editor(s)

© SPIE. Terms of Use
Back to Top