GE Sievers Innovox, Руководство по эксплуатации и обслуживанию

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GE Analytical Instruments ©2016 57 of 270 DLM 68100-09 EN Rev. A
Chapter 2: System Description
Sample Flow Path
In the Online mode, the InnovOx On-Line TOC Analyzer can monitor up to two sample streams, or in the optional
5-stream configuration, it can monitor up to five sample streams.
Additionally, a 60-mL or 40-mL vial filled with sample can be inserted into the vial port for analysis in the Grab
mode.
The Analyzer makes measurements in five concentration ranges: Up to 100 ppm , Up to 1,000 ppm , Up to
5,000 ppm , Up to 20,000 ppm , and Up to 50,000 ppm . The Analyzer automatically prepares and dispenses the
measurement recipe according to the range selected. In the Up to 1,000 ppm range, the Analyzer measures
concentrations up to 1,000-ppm organic carbon (NPOC or TOC) or 100 ppm IC. The sample is diluted with an
equal volume of low-TOC dilution water and reagents. In the
Up to 5,000 ppm range, the sample is diluted by a
factor of 5:1. The sample is diluted by a factor of 20:1 in the 20,000 ppm range, and the sample is diluted by a
factor of 50:1 in the 50,000 ppm range. In the Up to 100 ppm range, the sample is diluted by a factor of 0.7:1.
A measurement of a new sample begins with a “fast flush” which involves pumping sample into the Sample
Handling Module by its peristaltic pump. Next, reagents are drawn into the sample coil in the Sample Handling
Module by the syringe pump. Normally the syringe is empty and the sample coil contains dilution water. When
the reagents are drawn into the sample coil, the syringe fills with a volume of dilution water that equals the
volume of reagents to be used in the measurement. 6 M phosphoric acid (H
3
PO
4
) or 3M hydrochloric acid (HCl)
(referred to as Acid in the user interface) is drawn into the sample coil first, followed by the sodium persulfate
(Na
2
S
2
O
8
) reagent (referred to as Oxid or Oxidizer in the user interface).
The purpose of the acid is to reduce the pH to 2 or less; this converts any carbonate or bicarbonate salts to CO
2
.
The volume of the acid reagent that will be used in the analysis is determined by the Acid % setting. A value of
1% means that the volume of acid reagent will be 1% (V/V) of the total solution volume that later will be
contained in the sparging chamber.
The oxidizer has a concentration of 30% (W/V). The volume of the oxidizer reagent to be mixed with the other
solutions in the sparging chamber is determined by the Oxid % setting. A value of 15% means that the volume of
oxidizer reagent will be 15% (V/V) of the total solution volume that later will be contained by the sparging
chamber.
The syringe then empties, depositing the reagents into the sparging chamber. Next, the syringe fills with the
necessary volume of dilution water. The sample is then drawn into the sample coil. Because the sample only
enters the sample coil, the syringe and its three-way valve are protected against contamination by salts and
particulates in the samples. This greatly extends the life of the syringe and valve.
In the next step, the syringe pump empties the sample coil into the sparging chamber. The mixing bar in the
sparging chamber mixes the solution, and any particulates that were in the sample are suspended in the
homogeneous solution. Any IC in the sample is converted to CO
2
by the acid. If NPOC is to be measured, the
solution is sparged with CO
2
-free gas to remove the CO
2
before the solution is transferred to the reactor.