Reagent Consumption - Hach APA 6000 Operation Manual

Section 2

2.2 Reagent Consumption

Page 14
Reagent Consumption
4. A portion of the solution in the mixer is aspirated out and the
buffer/indicator reagent is added. This solution aliquot and the reagent are
both dispensed back into the mixer.
5. The solution in the mixer may now start to turn red.
6. Some of the solution is aspirated from the mixer and sent to the detector
to prime the reaction coil.
7. The rest of the solution is aspirated from the mixer, followed by a slug of
titrant reagent, and sent to the detector for titrimetric measurement using
a 612 nm LED and a 600 nm filter.
8. As the titrant disperses in the reaction coil, a plug of blue solution may be
seen going through the detector.
The use of inflection points in the titrimetric measurement eliminates the need
for a reference measurement, even for colored samples.
numbers and their function.
Table 2 Port Functions For High Range Hardness Analysis
Port # Function
1 Detector
2 Sample 1
3 Sample 2
4 Standard 1
5 Standard 2
The rate of reagent use depends on many factors, including the number of
times the instrument cycles, calibration frequency, and the number of clean
cycles. Table 3 provides the approximate volumes (in mL) of the reagents
consumed with each type of function per cycle.
Table 3 Reagent Consumption in mL
Solution Measurement
Sample
Reagent 1
Reagent 2
Reagent 3
Standard 1
Standard 2
Cleaning Solution
Port # Function
6 Waste
7 Reagent 3
8 Reagent 2 (indicator)
9 Reagent 1
10 Mixer
Calibration
5.07 0
0.140 1.12
0.16 2.56
0.10 1.6
0 64.2
0 35.4
0 0
Table 2 lists the port
Cleaning
2.0
0
0
0
0
0
6.8
6200018theory.fm