ΕΘΝΙΚΟ ΜΕΤΣΟΒΙΟ ΠΟΛΥΤΕΧΝΕΙΟ
ΕΘΝΙΚΟ ΜΕΤΣΟΒΙΟ ΠΟΛΥΤΕΧΝΕΙΟ
ΕΘΝΙΚΟ ΜΕΤΣΟΒΙΟ ΠΟΛΥΤΕΧΝΕΙΟ
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However, from the results of the batch experiments conducted this does not<br />
seem to happen in any of the ECs examined. This was probably due to the<br />
microbiological activity, particularly in the fourth batch experiment, where the<br />
columns A and B reached breakthrough limits earlier compared to the third batch<br />
experiment, but not columns C and D. Microbiological activity was also observed<br />
earlier in the fourth batch experiment, compared to the second and third batch<br />
experiment. This also seems to have affected the results from the fourth batch<br />
experiment, resulting in decreased correlation of GAC bed depth and column service<br />
time compared to the third batch experiment.<br />
Furthermore, the difference of the linear flow rate between the forth batch<br />
experiment and the second and third batch experiments is probably not statistically<br />
significant and so the changes of the values of the constants N0 and K are not<br />
statistically significant either. So, for the reasons aforementioned the results were<br />
assumed to be of a single linear flow rate (the average value of 3,39 m/h) and the<br />
values of the constants N0 and K were extracted from all batch experiments for each<br />
EC examined. Table 1 shows the final values of the constants N0 and K for each EC<br />
examined. Those constants are referred to a single linear flow rate (3,39 m/h).<br />
Table 1 : Final values of the constants N0 and K at 3,39 m/h for each EC examined.<br />
Emerging contaminant N0 {g/m 3 } K {m 3 /(g·h)} Breakthrough limit<br />
Bisphenol-A 12,82 7,48 10%<br />
Triclosan 8,41 19,69 7,5%<br />
Ibuprofen 8,89 15,99 20%<br />
Naproxen 9,14 25,88 20%<br />
Ketoprofen 9,46 15,18 20%<br />
Diclofenac 10,85 12,86 20%<br />
In the design of a GAC column unit in a typical water treatment plant in order<br />
to remove from water one of the ECs examined (Diclofenac) it seems that the surface<br />
needed is relatively large (551 m 2 ) probably due to the fact that the flow rate of the<br />
unit is very small compared to the flow rate of the plant. So, it is suggested the<br />
redesign of the unit with bigger flow rates and new constants N0 and K respectively.<br />
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