Xylem YSI Alyza IQ NH4, Руководство по эксплуатации

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Overview Alyza IQ NH4
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1.2 Metrological basics NH4-N / NH3-N , NH4
Ammonium In aqueous solutions, ammonia (NH
3
) and ammonium (NH
4
+
) are at equilibrium
(NH
3
+ H
2
O
→
NH
4
+
+ OH
-
).
In acidic solutions (pH value < 7) there are more ammonium ions,
in alkaline solutions (pH value > 7) there is more ammonia.
Measuring method The analyzer Alyza IQ NH4 measures the concentration of ammonium ions in
an aqueous solution.
By adding reagents to the sample, first the ammonium ions present are convert-
ed into ammonia, which then reacts further in the presence of hypochlorite ions
to form monochloramine. In further steps, the monochloramine formed reacts
with a phenol derivative with the aid of a catalyst to form the desired dye, which
is measured photometrically at a suitable wavelength.
The method detects both ammonium ions and ammonia. Both are linked via the
pH value of the sample.
Citation forms The ammonium concentration is quoted in milligrams per liter (mg/l). The value
can either refer to the total ammonium or only to the nitrogen atom contained
therein. The values can be converted as follows:
 1 mg N = 1.2879 mg NH4 = 1.2159 mg NH3
 1 mg NH4 = 0.7765 mg NH4-N
 1 mg NH3 = 0.8224 mg NH3-N
Concentration values referring to the nitrogen atom are indicated by the addition
NH4-N (citation form).
1.3 Product description
1.3.1 Overview
Application Analyzers of the Alyza IQ series are designed for online measurements in aque-
ous samples.
Measurement takes place photometrically, at adjustable intervals, including au-
tomatic sampling (sample filtration and sample feed).
Measuring system Analyzers of the Alyza IQ series are operated as "sensors" in the
Variant Measurement
Alyza IQ NH4 Ammonium measurements
e.g.
for regulation of the aeration control in biological acti-
vated sludge tanks in waste water treatment plants
Measurements in the final effluents of waste water
treatment plants
Measurements for water body and river monitoring