Thermo Scientific SOLA II Flare, Руководство пользователя

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Chapter 1
Product Overview
Thermo Scientific SOLA II Flare User Manual 1-3
The potential interferences to any UVF or PUVF detector, CO
2
and water
vapor, are formed during the combustion process required to convert the sulfur
compounds to SO
2
. The PUVF detector utilizes reflective band-pass filters to
optimize the light wavelength used for the excitation of the SO
2
molecules in
the temperature-controlled measuring chamber. This optimization of the light
wavelength eliminates the CO
2
interference.
Oxidative Pyrolysis
System
When measuring total sulfur with a PUVF detector, it is necessary to convert
100% of the sulfur compounds present in the sample to SO
2
. The combustion
system is a design unique to Thermo Scientific and allows the SOLA II Flare to
achieve the required conversion of all of the sulfur compounds to SO
2
. The
combustion system uses no catalyst to complete the conversion, and the simple
U-shaped quartz reaction tube is inexpensive and easily changed (normally
every 14 to 18 months). The 100% conversion is accomplished while
maintaining full-scale linearity and repeatability.
The SOLA II Flare utilizes two air-actuated microliter injection valves to
precisely control the amount of sample injected into the zero grade air carrier
gas. For gaseous samples, a backpressure regulator allows the pressure (sample
volume) to be held constant in the sample loop of the injection valve. Since the
sample heads of the injection valves are inside the analytical oven, the
temperature variable is eliminated. The sample passes into a mixing chamber
where the hydrocarbons and sulfur compounds are mixed with the oxygen in
zero-grade air. The thoroughly mixed gases flow into the pyrolyzer furnace,
where the oxygen present in the carrier air is used to combust the sample and
convert the carbon and sulfur compounds to CO
2
and SO
2
, respectively. A
small amount of water vapor is created during the combustion process, but as
the amount is so negligible, it is of no concern to the PUVF detector.
Diagnostics and
Communication Options
The SOLA II Flare offers a comprehensive diagnostics and communications
package as a standard feature. The communications package offers the user a
wide variety of options, from analog and contact closure communications, to
Modbus-based communications over Ethernet- or RS485-based
communications.
The SOLA II Flare also provides a comprehensive diagnostic package designed
to minimize down time and provide useful troubleshooting information.
Several diagnostic points are continually monitored and will trip the global
alarm. The monitored points are: