Anions in potable waters - Determination of Anions in Natural and Treated Waters - page 470

[HCO 3 − ] in mg L −1 [HCO 3 − ] in mg

L −1

segmented
method

variation %

1 226 268 248 0.99

2 485 546 532 0.46

3 266 298 305 0.98

4 266 306 313 0.56

5 213 232 236 0.71

6 250 276 288 0.66

7 120 142 135 0.98

8 160 259 287 0.48

9 267 291 324 0.31

10 480 317 332 0.56

11 107 120 110 0.26

12 117 123 110 0.27

13 119 123 112 0.24

14 120 125 113 0.31

15 113 109 110 0.42

16 113 117 108 0.55

17 96 98 95 0.30

a 15 tests were carried out on each sample
Source: Reproduced with permission from United Trades Press [1]

7.1.3 Flow injection analysis, alkalinity, pH and total ionic concentration

Canate et al. [3] have described a flow injection analysis system for the simultaneous
determination of the alkalinity, pH and total ionic concentration of potable water. The pH
measurements are performed by means of a glass calomel microelectrode inserted in to
the water stream. The alkalinity and total ionic concentration are determined by flow
injection analysis titrations, acid base reactions and spectrophotometric detection. In
addition, the determination of the total ionic concentration requires the incorporation of
an ion exchange mini-column. The results obtained are in agreement with those obtained
by conventional methods for the determination of these parameters and are obtained with
a higher degrees of automation, which results in a smaller reagent consumption, greater
convenience and higher reproducibility and sampling frequency. A microcomputer is
installed for on-line data collection and the treatment and display of results.