Yokogawa In-Situ Gas Analyzer TDLS200 - Manual (Page 4)

4
IM11Y01B01-12E-A
1st Edition
1 Combustion Overview
1.1 Introduction
In this addendum to the Users Guide for TDLS200, the installation for combustion is detailed. This
information pertains to oxygen and CO/CH4 analyzers. Some typical combustion related
installations are outlined below:
•
Ethylene Cracking Furnaces, Refinery Heaters, Reformer Units, VCM Cracking
Furnaces, Waste Incineration, Power Generation systems, etc.
• Radiant section, OPL 1-30m (~99ft), +/- atmospheric pressure, <1200C (~2200F):
o
Oxygen 0-21% - for control or monitoring
o
CO 0-5,000ppm – for control, monitoring or safety
+ CH4 0-5% - breakthrough monitoring and/or safety <800C (~1475F)
•
Convection-Economizer section, OPL 1-30m (~99ft), +/- atmospheric pressure, <1200C
(~2200F):
o
Oxygen 0-21% - for control or monitoring
o
CO 0-5,000ppm – for control, monitoring or safety
+ CH4 0-5% - breakthrough monitoring and/or safety <800C (~1475F)
•
Combustion flue, OPL 1-10m (~33ft), +/- atmospheric pressure, <500C (~930F):
o
Oxygen 0-21% - for control or monitoring
o
CO 0-5,000ppm – for control, monitoring or safety
+ CH4 0-5% - breakthrough monitoring and/or safety <800C (~1475F)
•
Waste Incineration, OPL 1-10m (~33ft), +/- atmospheric pressure, <1200C (~2200F):
o
Oxygen 0-21% - for control or monitoring
o
CO 0-5,000ppm – for control, monitoring or safety
+ CH4 0-5% - breakthrough monitoring and/or safety <800C (~1475F)
For in-situ application (typically large scale combustion) the optical path lengths are generally very
long (7-30m for large scale combustion and ethylene furnaces). Standard TDL optics and laser
beam configurations are unsuitable because of the mechanical stability of these large scale
combustion systems. Yokogawa Laser Analysis Division therefore designed and developed the
concept of a diverging beam (i.e. a laser beam that expands over distance) and a large aperture
optics detector scheme (i.e. a large target for the laser to hit).
The general concept of diverging beam and large aperture optics is shown below: