wtw 208210, Инструкция по эксплуатации

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BOD
5
determination
Sample preparation
28
BOD
5
determination
Normally municipal wastewater does not contain toxic or impeding substances.
There are enough nutrient salts and suitable microorganisms. Under these
conditions the
BOD
5
determination with the OxiTop

measuring system is possible
in the undiluted sample
Required instruments and accessories
OxiTop

measuring system
Inductive stirring system
Incubator thermostatic box (temperature 20°C ± 1K)
Sample bottles brown (nominal volume 510 ml)
Stirring rods
Stirring rod remover
suitable overflow measuring beakers
Rubber quivers
Sodium hydroxide tablets
Selection of sample volume
Estimate the BOD
5
value to be expected for the wastewater sample:
Expected BOD
5
value

80 % of the COD value
Look for corresponding measuring range in the following chart and gather correct
values for sample volume and factor.
Sample volume (ml) Measuring range (mg/l) Factor
432 0 - 40 1
365 0 - 80 2
250 0 - 200 5
164 0 - 400 10
97 0 - 800 20
43.5 0 - 2000 50
22.7 0 - 4000 100
Sample preparation
See following WTW application reports:

WTW Application report 895230:
"BOD measurement in household wastewater"

WTW Application report 895231:
"BOD measurement in organically heavily contaminated wastewater"

WTW Application report 895232:
"BOD measurement with presence of impeding or toxic substances"