Thermo Scientific AQUAfast AQ3700, User Manual

Page: 68 / 264

Thermo Scientific Orion AQUAfast AQ3700 Colorimeter User Guide
1.1 Methods
COD HR
with Tube Test
0 – 15 g/l O
2
(= ^ 0 – 15 000 mg/l O
2
)
Insert the adapter for 16 mm Ø vials.
1. Open one white capped reaction vial and add
0.2 ml
deionized water (this is the blank (Note 1)).
2. Open another white capped reaction vial and add
0.2 ml of the water sample
(this is the sample).
3. Close the vials with the cap tightly. Invert the vial gently
several times to mix the contents.
(CAUTION: The vial will become hot during mixing!)
4. Heat the vials for
120 minutes
in the preheated reactor
at a temperature of
150°C
.
5. (CAUTION: The vials are hot!)
Remove the tubes from the heating block and allow them
to cool to 60°C or less. Mix the contents by carefully
inverting each tube several times while still warm.
Then allow the tubes to cool to ambient temperature
before measuring. (Note 2).
6. Place the vial (the blank (Note 3, 4)) in the sample
chamber making sure that the marks are
l
aligned.
7. Press ZERO key.
8. Remove the vial from the sample chamber.
9. Place the vial (the sample (Note 3, 4)) in the sample
chamber making sure that the marks are
l
aligned.
10. Press TEST key.
The result is shown in the display in g/l COD.
Zero accepted
prepare Test
press TEST
prepare Zero
press ZERO
Ø 16 mm
2 3 1