Parameter calibration results for models in Tables 1 and 2 are presented in Table 3. Calibrations were performed through three distinct model structures: the designation of the reaction order (n) as an integer for Equation (2) (e.g., models 1–9 in Table 3), calibration incorporating parameter n as a real number (e.g., models 10 and 11 in Table 3), and the most comprehensive calibration involving a flexible concentration of the stable component () instead of a designated
for a lower detection limit of the sensor (e.g., models 12–14 in Table 3).
Calibrated parameters for candidate chlorine models with different hydraulic conditions
Model . | Title . | Parameter . | Steady . | 40 min . | 20 min . | 10 min . | 5 min . | 2.5 min . |
---|---|---|---|---|---|---|---|---|
1 | 1st order | k (day−1) | 0.479 | 0.440 | 0.397 | 0.286 | 0.240 | 0.185 |
2 | 2nd order | k (day−1) | 0.392 | 0.357 | 0.330 | 0.238 | 0.201 | 0.141 |
3 | 3rd order | k (day−1) | 0.318 | 0.285 | 0.270 | 0.195 | 0.166 | 0.105 |
4 | 4th order | k (day−1) | 0.260 | 0.244 | 0.244 | 0.163 | 0.139 | 0.078 |
5 | Limited 1st order | k (day−1) | 0.488 | 0.458 | 0.397 | 0.292 | 0.244 | 0.188 |
6 | Limited 2nd order | k (day−1) | 0.406 | 0.366 | 0.336 | 0.246 | 0.208 | 0.145 |
7 | Limited 3rd order | k (day−1) | 0.334 | 0.305 | 0.275 | 0.206 | 0.175 | 0.110 |
8 | Limited 4th order | k (day−1) | 0.278 | 0.250 | 0.250 | 0.175 | 0.156 | 0.084 |
9 | Parallel 1st order | w | 0.995 | 1.000 | 0.851 | 0.753 | 0.711 | 0.652 |
k1 (day−1) | 0.468 | 0.440 | 0.400 | 0.288 | 0.240 | 0.184 | ||
k2 (day−1) | 0.480 | 0.439 | 0.390 | 0.283 | 0.240 | 0.185 | ||
10 | nth order | n | 0.407 | 0.997 | 0.967 | 0.563 | 0.701 | 0.507 |
k (day−1) | 0.527 | 0.437 | 0.401 | 0.305 | 0.250 | 0.213 | ||
11 | Limited nth order | n | 0.390 | 0.980 | 0.945 | 0.547 | 0.683 | 0.478 |
k (day−1) | 0.531 | 0.437 | 0.409 | 0.309 | 0.254 | 0.214 | ||
12 | Combined ‘1 + 1’ | w | 0.942 | 0.992 | 0.959 | 0.903 | 0.859 | 0.792 |
k1 (day−1) | 0.479 | 0.440 | 0.399 | 0.287 | 0.240 | 0.185 | ||
k2 (day−1) | 0.478 | 0.440 | 0.390 | 0.276 | 0.238 | 0.185 | ||
c* (mg/L) | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | ||
13 | Combined ‘1 + n’ | w | 0.125 | 0.332 | 0.314 | 0.259 | 0.083 | 0.015 |
k1 (day−1) | 0.407 | 0.995 | 0.974 | 0.248 | 0.082 | 0.057 | ||
n | 0.348 | 0.131 | 0.348 | 0.423 | 0.571 | 0.573 | ||
k2 (day−1) | 0.500 | 0.291 | 0.279 | 0.279 | 0.277 | 0.211 | ||
c* (mg/L) | 0.020 | 0.029 | 0.040 | 0.040 | 0.072 | 0.072 | ||
14 | Combined ‘n + n’ | w | 0.424 | 0.304 | 0.261 | 0.204 | 0.192 | 0.191 |
n1 | 0.375 | 0.878 | 0.804 | 0.604 | 0.582 | 0.165 | ||
k1 (day−1) | 0.255 | 0.998 | 0.856 | 0.211 | 0.190 | 0.060 | ||
n2 | 0.364 | 0.069 | 0.433 | 0.501 | 0.628 | 0.651 | ||
k2 (day−1) | 0.438 | 0.295 | 0.295 | 0.263 | 0.219 | 0.187 | ||
c* (mg/L) | 0.034 | 0.003 | 0.011 | 0.032 | 0.037 | 0.045 |
Model . | Title . | Parameter . | Steady . | 40 min . | 20 min . | 10 min . | 5 min . | 2.5 min . |
---|---|---|---|---|---|---|---|---|
1 | 1st order | k (day−1) | 0.479 | 0.440 | 0.397 | 0.286 | 0.240 | 0.185 |
2 | 2nd order | k (day−1) | 0.392 | 0.357 | 0.330 | 0.238 | 0.201 | 0.141 |
3 | 3rd order | k (day−1) | 0.318 | 0.285 | 0.270 | 0.195 | 0.166 | 0.105 |
4 | 4th order | k (day−1) | 0.260 | 0.244 | 0.244 | 0.163 | 0.139 | 0.078 |
5 | Limited 1st order | k (day−1) | 0.488 | 0.458 | 0.397 | 0.292 | 0.244 | 0.188 |
6 | Limited 2nd order | k (day−1) | 0.406 | 0.366 | 0.336 | 0.246 | 0.208 | 0.145 |
7 | Limited 3rd order | k (day−1) | 0.334 | 0.305 | 0.275 | 0.206 | 0.175 | 0.110 |
8 | Limited 4th order | k (day−1) | 0.278 | 0.250 | 0.250 | 0.175 | 0.156 | 0.084 |
9 | Parallel 1st order | w | 0.995 | 1.000 | 0.851 | 0.753 | 0.711 | 0.652 |
k1 (day−1) | 0.468 | 0.440 | 0.400 | 0.288 | 0.240 | 0.184 | ||
k2 (day−1) | 0.480 | 0.439 | 0.390 | 0.283 | 0.240 | 0.185 | ||
10 | nth order | n | 0.407 | 0.997 | 0.967 | 0.563 | 0.701 | 0.507 |
k (day−1) | 0.527 | 0.437 | 0.401 | 0.305 | 0.250 | 0.213 | ||
11 | Limited nth order | n | 0.390 | 0.980 | 0.945 | 0.547 | 0.683 | 0.478 |
k (day−1) | 0.531 | 0.437 | 0.409 | 0.309 | 0.254 | 0.214 | ||
12 | Combined ‘1 + 1’ | w | 0.942 | 0.992 | 0.959 | 0.903 | 0.859 | 0.792 |
k1 (day−1) | 0.479 | 0.440 | 0.399 | 0.287 | 0.240 | 0.185 | ||
k2 (day−1) | 0.478 | 0.440 | 0.390 | 0.276 | 0.238 | 0.185 | ||
c* (mg/L) | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | 0.000 | ||
13 | Combined ‘1 + n’ | w | 0.125 | 0.332 | 0.314 | 0.259 | 0.083 | 0.015 |
k1 (day−1) | 0.407 | 0.995 | 0.974 | 0.248 | 0.082 | 0.057 | ||
n | 0.348 | 0.131 | 0.348 | 0.423 | 0.571 | 0.573 | ||
k2 (day−1) | 0.500 | 0.291 | 0.279 | 0.279 | 0.277 | 0.211 | ||
c* (mg/L) | 0.020 | 0.029 | 0.040 | 0.040 | 0.072 | 0.072 | ||
14 | Combined ‘n + n’ | w | 0.424 | 0.304 | 0.261 | 0.204 | 0.192 | 0.191 |
n1 | 0.375 | 0.878 | 0.804 | 0.604 | 0.582 | 0.165 | ||
k1 (day−1) | 0.255 | 0.998 | 0.856 | 0.211 | 0.190 | 0.060 | ||
n2 | 0.364 | 0.069 | 0.433 | 0.501 | 0.628 | 0.651 | ||
k2 (day−1) | 0.438 | 0.295 | 0.295 | 0.263 | 0.219 | 0.187 | ||
c* (mg/L) | 0.034 | 0.003 | 0.011 | 0.032 | 0.037 | 0.045 |