Thermo Scientific Mercury Freedom 80i, Manual

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Thermo Fisher Scientific Mercury System Manual 1-1
Chapter 1
Introduction
Note This manual is for use with the Mercury Freedom
™
System
integrated by Thermo Fisher Scientific. Systems integrated by others will
vary from the information provided in this document.
▲
The Model 80 i is normally configured as one component of an integrated
Hg Continuous Emission Monitoring System (CEMS). The Thermo
Scientific Mercury Freedom
™
System is comprised of a Hg analyzer
(Model 80 i ), a Hg calibrator (Model 81 i ), a Hg probe controller (Model
82 i ), and a Hg probe (Model 83 i ) along with additional peripheral
components, such as a zero air supply, umbilical, and instrument rack.
However, the Model 80
i is also available as a stand-alone instrument.
The Model 80 i Analyzer is based on the principle that Hg atoms absorb
ultraviolet (UV) light at 254 nm, become excited, then decay back to the
ground energy state, emitting (fluorescing) UV light at the same
wavelength. Specifically,
) 254 ( * ) 254 ( nm h + Hg Hg nm h + Hg
ν ν
→ →
The sample from the Hg probe (Model 83 i ) is introduced to the rear panel
of the instrument as either Total Hg or Elemental Hg from the appropriate
probe umbilical connection (see
Figure 1–1
). When the Model 80 i is
sampling Total Hg, the total sample is routed into the fluorescence
chamber via Solenoids S1 (NO state) and S3 (NO state). During this time,
the Elemental Hg sample bypasses the chamber via Solenoid S2 (NO state).
When the Model 80 i is sampling Elemental Hg, the elemental sample is
routed via Solenoids S2 (normally closed (NC) state) and S3 (normally
open (NO) state) into the fluorescence chamber. During this time, the
Total Hg sample bypasses the chamber via Solenoid S1 (NC state). As the
monitored sample (Total or Elemental) leaves the optical chamber, it passes
through a flow sensor, then to an external pump. The external pump is
used to draw the sample through the instrument and to create the
instrument vacuum which is measured with the pressure transducer.
System Overview
Model 80
i