Xylem WTW OxiTop-i, Руководство по эксплуатации

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Operation OxiTop
®
(-i/-IDS)
16
ba77059e01 03/2019
4.3 BOD determination
Municipal wastewater does not normally contain any toxic or inhibiting sub-
stances. There are enough nutrient salts and suitable microorganisms present.
Under these conditions, BOD determination in the undiluted sample using the
OxiTop
®
(-i/-IDS) measuring system is possible.
Instruments and
accessories
required
 OxiTop
®
(-i/-IDS) measuring head
 Stirring platform (inductive stirring system)
 Thermostat cabinet or box (temperature 20 °C ± 1 °C)
 Brown sample bottles (bottle volume 510 ml)
 Magnetic stirring rods
 Magnetic stirring rod remover
 Suitable overflow volumetric flask
 Rubber sleeves
 Nitrification inhibitor (NTH 600)
 Sodium hydroxide tablets (NHP 600)
Further documents
for BOD
determination
 WTW application reports (see www.wtw.com)
 DIN EN 1899-2
Water quality - Determination of biochemical oxygen demand after n days
(BODn) - Part 2: Method for undiluted samples (ISO 5815:1989, modified);
German version EN 1899-2:1998
4.4 Carrying out the BOD determination
4.4.1 Preparing the measurement
Determining the
sample volume
10. Exit the setting with
<M>
.
1. Estimate the expected BOD value for the waste water sample.
The expected BOD value is approximately 50% of the COD value.
2. Look for the relevant measuring range in the following table and take
the values for sample volume and multiplier.