YOKOGAWA RC400G, Руководство пользователя

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<4. Operation>
4-4
IM 12F4A1-01E
4.2 Preparation for Operation
4.2.1 Reagent Preparation
Reagent used for measurement differs in free available chlorine measurement and residual
chlorine (total chlorine) measurement. Also, in total chlorine measurement, the component
amounts in the reagent must be changed depending on the chlorine concentration in the solution
to be measured.
Prepare reagents using the following procedure for each case. Keep prepared reagents in
reagent tanks.
Reagents cannot be imported from Japan. Purchase them from local suppliers.
l
Preparation of Reagent for Free Available Chlorine Measurement (max.
concentration: 10 mg/l)
As reagent components, use potassium bromide (KBr) which reacts with the free available
chlorine present in a measuring sample to liberate bromine, acetic acid (CH
3
COOH) for
maintaining measuring sample pH at 4.5 to 5.0, and sodium acetate (CH
3
COONa).
If a reagent solution of 100 liter is to be prepared, obtain a mixed reagent solution of a total of a
100 liter by dissolving 4000 g of JIS grade 1 KBr, 1000 g of sodium acetate and 1000 ml of acetic
acid (95 % or higher) into approx. 80 liter of purified water, and then adding additional purified
water to make 100 liter.
Table 4.1 Reagent Composition and Its Component Quantities
Measurement Object
Reagent Composition
Free Chlorine Required quantity of containers
for each measurement (approx.
for 45 days)
Quantity in 100 l
KBr 4000 g 500 g x 8
CH
3
COONa 1000 g 500 g x 2
CH
3
COOH 1000 ml 500 ml x 2
l
Preparation for Combined Chlorine
Table 4.2 Reagent Composition and Its Component Quantities
Measurement Object
Reagent Composition
Free Chlorine Required quantity of containers
for each measurement (approx.
for 45 days)
Quantity in 100 l
KBr 4000 g 500 g x 8
CH
3
COONa 5400 g 500 g x 11
CH
3
COOH 200 ml 500 ml x 1 (2 times)
l
Preparation of Reagent for Measuring Residual Chlorine
As reagent components, use potassium iodide (KI) which reacts with free chlorine present in a
measuring sample to liberate iodine, acetic acid (CH
3
COOH) for maintaining measuring sample
pH at 4.5 or less, and sodium acetate (CH
3
COONa).
The amount of potassium iodide to be used varies with the residual chlorine concentration. See
Table 4.3.
14th Edition : Jul. 15, 2020