Comparison of DBP results across the two waters (Table 3) showed that increasing bromide resulted in increased concentration of THMs after 72 hours, with the total THM concentrations achieved for the highest bromide concentrations for each water source approximately double that at the initial/lowest bromide concentrations. This was caused by conversion to increased amounts of the brominated species. The extra bromide had less effect on the total HAA concentration, particularly for the WA water source. This is likely to have been a result of more substitution reactions occurring within the various HAA species rather than the creation of new HAAs.
Comparison of DBP species for SA and WA treated water with increasing bromide addition
SA treated water . | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Br concentration | 0.06 mg/L | 0.21 mg/L | 0.39 mg/L | |||||||
DBPs | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | |
THM species (μg/L) | Chloroform | 10 | 18 | 57 | 6 | 12 | 40 | 4 | 7 | 20 |
Bromodichloromethane | 13 | 18 | 28 | 16 | 27 | 52 | 16 | 28 | 57 | |
Dibromochloromethane | 5 | 7 | 9 | 19 | 28 | 40 | 30 | 45 | 75 | |
Bromoform | <1 | <1 | <1 | 5 | 6 | 7 | 18 | 20 | 25 | |
Total THMs (THM4) | 28 | 42 | 94 | 46 | 72 | 139 | 68 | 100 | 176 | |
HAA species (μg/L) | Chloro-HAAs | 12 | 21 | 62 | 6 | 9 | 39 | 4 | 7 | 38 |
Chloro-bromo-HAAs | 11 | 17 | 32 | 18 | 32 | 58 | 21 | 37 | 79 | |
Bromo-HAAs | 1 | 1 | 2 | 4 | 6 | 13 | 11 | 15 | 29 | |
Total HAAs (HAA9) | 24 | 39 | 96 | 28 | 47 | 110 | 36 | 59 | 146 | |
AOX (μg/L) | 169 | 199 | 287 | 116 | 162 | 270 | 107 | 164 | 280 | |
WA treated water . | ||||||||||
Br concentration | 0.55 mg/L | 0.9 mg/L | 1.8 mg/L | |||||||
DBPs | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | |
THM species (μg/L) | Chloroform | 15 | 25 | 59 | 9 | 16 | 37 | 4 | 5 | 7 |
Bromodichloromethane | 42 | 64 | 99 | 41 | 64 | 113 | 27 | 38 | 56 | |
Dibromochloromethane | 60 | 83 | 100 | 80 | 117 | 179 | 86 | 118 | 201 | |
Bromoform | 24 | 27 | 26 | 58 | 67 | 81 | 152 | 187 | 310 | |
Total THMs (THM4) | 140 | 199 | 283 | 188 | 264 | 409 | 269 | 348 | 573 | |
HAA species (μg/L) | Chloro-HAAs | 18 | 24 | 69 | 9 | 14 | 28 | 4 | 6 | 8 |
Chloro-bromo-HAAs | 55 | 76 | 117 | 56 | 82 | 121 | 48 | 63 | 90 | |
Bromo-HAAs | 29 | 33 | 42 | 45 | 56 | 74 | 95 | 115 | 146 | |
Total HAAs (HAA9) | 102 | 133 | 228 | 110 | 152 | 223 | 147 | 184 | 244 | |
AOX (μg/L) | 383 | 493 | 707 | 405 | 471 | 707 | 442 | 559 | 975 |
SA treated water . | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|
Br concentration | 0.06 mg/L | 0.21 mg/L | 0.39 mg/L | |||||||
DBPs | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | |
THM species (μg/L) | Chloroform | 10 | 18 | 57 | 6 | 12 | 40 | 4 | 7 | 20 |
Bromodichloromethane | 13 | 18 | 28 | 16 | 27 | 52 | 16 | 28 | 57 | |
Dibromochloromethane | 5 | 7 | 9 | 19 | 28 | 40 | 30 | 45 | 75 | |
Bromoform | <1 | <1 | <1 | 5 | 6 | 7 | 18 | 20 | 25 | |
Total THMs (THM4) | 28 | 42 | 94 | 46 | 72 | 139 | 68 | 100 | 176 | |
HAA species (μg/L) | Chloro-HAAs | 12 | 21 | 62 | 6 | 9 | 39 | 4 | 7 | 38 |
Chloro-bromo-HAAs | 11 | 17 | 32 | 18 | 32 | 58 | 21 | 37 | 79 | |
Bromo-HAAs | 1 | 1 | 2 | 4 | 6 | 13 | 11 | 15 | 29 | |
Total HAAs (HAA9) | 24 | 39 | 96 | 28 | 47 | 110 | 36 | 59 | 146 | |
AOX (μg/L) | 169 | 199 | 287 | 116 | 162 | 270 | 107 | 164 | 280 | |
WA treated water . | ||||||||||
Br concentration | 0.55 mg/L | 0.9 mg/L | 1.8 mg/L | |||||||
DBPs | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | 0.5 hours | 4 hours | 72 hours | |
THM species (μg/L) | Chloroform | 15 | 25 | 59 | 9 | 16 | 37 | 4 | 5 | 7 |
Bromodichloromethane | 42 | 64 | 99 | 41 | 64 | 113 | 27 | 38 | 56 | |
Dibromochloromethane | 60 | 83 | 100 | 80 | 117 | 179 | 86 | 118 | 201 | |
Bromoform | 24 | 27 | 26 | 58 | 67 | 81 | 152 | 187 | 310 | |
Total THMs (THM4) | 140 | 199 | 283 | 188 | 264 | 409 | 269 | 348 | 573 | |
HAA species (μg/L) | Chloro-HAAs | 18 | 24 | 69 | 9 | 14 | 28 | 4 | 6 | 8 |
Chloro-bromo-HAAs | 55 | 76 | 117 | 56 | 82 | 121 | 48 | 63 | 90 | |
Bromo-HAAs | 29 | 33 | 42 | 45 | 56 | 74 | 95 | 115 | 146 | |
Total HAAs (HAA9) | 102 | 133 | 228 | 110 | 152 | 223 | 147 | 184 | 244 | |
AOX (μg/L) | 383 | 493 | 707 | 405 | 471 | 707 | 442 | 559 | 975 |