Supplementary Information
APPLICABILITY OF OZONE AND BIOLOGICAL ACTIVATED
CARBON FOR POTABLE REUSE
Daniel Gerrity1,2,*, Emily Owens-Bennett2, Teresa Venezia2, Benjamin D. Stanford3, Megan
H. Plumlee4, Jean Debroux4, R. Shane Trussell2
1
Department of Civil and Environmental Engineering and Construction, University of Nevada,
Las Vegas, Las Vegas, NV
2
Trussell Technologies, Inc., Pasadena, CA
3
4
Hazen and Sawyer, Raleigh, NC
Kennedy/Jenks Consultants, San Francisco, CA
*Corresponding Author. Mailing Address: 4505 South Maryland Parkway, Box 454015, Las
Vegas, NV 89154-4015. Phone: 1-702-895-3955. Fax: 1-702-895-3936. Email:
Daniel.Gerrity@unlv.edu
S1
Text S1. Description of Bench-Scale Ozone Experiments
Ozone doses were administered by transferring an aliquot of the ozone stock solution into
500-mL or 1-L amber glass bottles. It is important to note that the ozone stock solution was
dissolved in distilled water so the ozone spike effectively diluted the target water matrix.
Particularly for wastewaters with high TOC values, ozone efficacy is affected by the potentially
large volume of ozone added to each sample, which dilutes all of the wastewater constituents.
With the exception of the ozone demand and decay experiments, an iterative approach was used
to calculate the highest ozone spiking volume (i.e., for an O3:TOC ratio of 1.5) for each
wastewater since this condition had the greatest dilution effect. Regardless of the O3:TOC value,
the volume of wastewater in each sample was held constant based on the difference between the
total sample volume (e.g., 1 L) and the volume of ozone stock for the O3:TOC ratio of 1.5. For
the lower O3:TOC ratios, less ozone stock was required so the samples were supplemented with
distilled water to target final volumes of 500 mL or 1 L. The O3:TOC values, and inherently the
ozone doses, were based on the final TOC value of each wastewater after accounting for the
dilution effect. In calculating relative treatment levels (e.g., reduction in TOrC concentrations or
UV254 absorbance), the ambient levels were also adjusted for this dilution effect. Nitrite was not
detected in either wastewater matrix so it did not factor into the dosing calculations. Example
dosing calculations are provided below for the chlorinated tertiary effluent; the calculations also
illustrate how to account for nitrite and hydrogen peroxide, when applicable.
Samples analyzed prior to the bench-scale experiments indicated that the initial TOC
concentration in the chlorinated tertiary effluent was 8.20 mg-C/L, and the initial NO2concentration was <0.25 mg-N/L or <0.82 mg-NO2/L. Based on a measured ozone stock
concentration of 80 mg/L, an iterative calculation was performed to determine the required ozone
S2
spiking volume for an O3:TOC ratio of 1.5. The final ozonated sample contained 867 mL of
wastewater and 133 mL of ozone stock, which diluted the TOC concentration to 7.11 mg-C/L.
The remaining volumes are summarized in Table 1. The equations below were used to verify the
dosing procedure.
If nitrite had been present, it would have been necessary to modify the dosing calculation
to account for this rapid reaction (Eq. S1).
[S1]
O3 + NO2-  O2 + NO3-
Since NO2 = 46 g/mole as NO2 and O3 = 48 g/mole, the reaction requires an approximate 1:1
mass ratio in order to satisfy the ozone demand caused by nitrite. Therefore, assuming standard
mass-based ratios for O3:TOC and O3:NO2, Eq. S2 can be used to verify the ozone dose; Eq. S3
shows the actual values for an O3:TOC ratio of 1.5.
[S2]
O3 (mg/L) = O3:TOC x [Dil. TOC] (mg-C/L) + [Dil. NO2-] (mg-NO2/L)
[S3]
O3 (mg/L) = 1.5 x 7.11 mg-C/L + 0 mg-NO2/L = 10.7 mg/L
Although it was not used in this study, H2O2 is sometimes added to the system to
expedite the decomposition of ozone into hydroxyl radicals and reduce bromate formation; a
simplified reaction is described in Eq. S4.
[S4]
H2O2 + 2O3  2•OH + 3O2
Since the molecular weights of H2O2 (34 g/mole) and O3 (48 g/mole) are different, H2O2 addition
is often described on a molar basis, as opposed to the mass-based ratios for O3:TOC and O3:NO2.
Based on the simplified stoichiometry above, molar H2O2:O3 ratios of 0.5 and 1.0 are often used.
The molar ratio of 0.5 is based on balanced stoichiometry, while the molar ratio of 1.0 is used to
provide excess H2O2 for competing reactions. Since the nitrite-associated ozone demand is
theoretically unavailable for reaction with H2O2, that portion of the applied ozone dose is not
S3
included. Eq. S5-S7 describe these calculations in general terms and for mass-based O3:TOC and
molar H2O2:O3 ratios of 1.5 and 1.0, respectively, in the SJCWRP effluent.
[S5]
Modified O3 (mg/L) = O3:TOC x [Dil. TOC] (mg-C/L)
[S6]
H2O2 (mg/L) = Modified O3 (mg/L) x
[S7]
H2O2 (mg/L) = 1.5 x 7.11 mg/L x
1 mmole O3
48 mg O3
1 mmole O3
48 mg O3
x molar H2 O2 : O3 x
34 mg H O2
x 1.0 x 1 mmole H2
2 O2
34 mg H2 O2
1 mmole H2 O2
= 7.6 mg/L
A similar procedure was used to calculate the volumes and doses for the SJCWRP
secondary effluent, as summarized in Table S1. For the ozone demand and decay experiments,
the wastewater volumes were held constant, but the final reaction volumes varied (Table S2).
The corresponding ozone stock and diluted TOC concentrations are summarized in Table S3.
Table S1. Experimental Volumes for the Ozone Oxidation Experiments
Secondary Effluent Volumes 1
Tertiary Effluent Volumes 2
3
4
3
WW
Distilled
O3
O3
WW
Distilled
O3 5
O3
(mL)
(mL)
(mL)
(mg/L)
(mL)
(mL)
(mL)
(mg/L)
0.25
8386
138
24
1.9
867
110
23
1.8
0.50
884
78
38
3.8
867
89
44
3.6
1.00
884
38
78
7.7
867
44
89
7.1
1.50
884
0
116
11.5
867
0
133
10.7
1
Secondary: Initial TOC = 8.65 mg-C/L, diluted TOC = 7.65 mg-C/L, NO2 < 0.25 mg-N/L
2
Tertiary: Initial TOC = 8.20 mg-C/L, diluted TOC = 7.11 mg-C/L, NO2 < 0.25 mg-N/L
3
WW = wastewater
4
O3 stock concentration during secondary experiments (except O3:TOC of 0.25) = 99 mg/L
5
O3 stock concentration during tertiary experiments = 80 mg/L
6
Erroneously used 80 mg/L ozone stock: O3:TOC = 0.26 and diluted TOC = 7.25 mg-C/L
O3:TOC
Table S2. Experimental Volumes for the Ozone Demand and Decay Experiments
O3:TOC
0.26
0.53
1.10
1.72
Secondary Effluent Volumes
WW
Distilled O3 (mL)
O3
(mL)
(mL)
(mg/L)
500
0
11
2.2
500
0
29
4.3
500
0
61
8.7
500
0
75
13.0
Tertiary Effluent Volumes
WW
Distilled
O3
O3
(mL)
(mL)
(mL)
(mg/L)
500
0
12
2.1
500
0
29
4.1
500
0
51
8.2
500
0
75
12.3
S4
Table S3. Ozone Stock and TOC Concentrations for the Ozone Demand and Decay Experiments
O3:TOC
0.26
0.53
1.10
1.72
Secondary Effluent
O3 Stock
Diluted TOC
(mg/L)
(mg-C/L)
100
8.46
78
8.17
80
7.71
100
7.53
Tertiary Effluent
O3 Stock
TOC
(mg/L)
(mg-C/L)
88
8.01
76
7.76
88
7.44
94
7.13
Figure S1. Measured instantaneous ozone demand (IOD) as a function of O3:TOC ratio.
Figure S2. First order ozone decay rate constant as a function of O3:TOC ratio.
S5
Figure S3. Time required for complete ozone decay as a function of O3:TOC ratio.
S6
Table S4. TOrC Concentrations (ng/L)
Increasing Treatment1
Target Compound
Ambient
Chlorinated
Tertiary
Effluent
Ambient
Secondary
Effluent
Ozonated
Secondary
Effluent
O3:TOC=0.262
Ozonated
Secondary
Effluent
O3:TOC=0.502
Ozonated
Secondary
Effluent
O3:TOC=1.002
Ozonated
Secondary
Effluent
O3:TOC=1.502
1,7-Dimethylxanthine
2,4-D
4-nonylphenol
4-tert-octylphenol
Acesulfame-K
Acetaminophen
Albuterol
Amoxicillin
Andorostenedione
Atenolol
Atrazine
Azithromycin
Bendroflumethiazide
Bezafibrate
Bisphenol A
Bromacil
Butalbital
Butylparaben
Caffeine
Carbadox
Carbamazepine
Carisoprodol
Chloramphenicol
Chloridazon
Chlorotoluron
Cimetidine
Clofibric Acid
Cotinine
Cyanazine
DACT
DEA
DEET
Dehydronifedipine
DIA
Diazepam
Diclofenac
Diuron
Erythromycin
Estradiol
Estrone
Ethinyl Estradiol
Ethylparaben
Flumeqine
Fluoxetine
Gemfibrozil
Ibuprofen
Iohexal
Iopromide
<5
300
860
8,400
18,000
7.5
6
< 20
<5
160
<5
N/A
<5
11
< 10
<5
<5
<5
60
<5
290
140
< 10
<5
<5
<5
<5
46
<5
19
<5
46
240
<5
<5
30
46
180
<5
<5
<5
< 20
< 10
14
78
< 15
1,500
3,400
<5
<5
1,400
18,000
24,000
68
15
1,600
<5
450
<5
N/A
<5
13
< 10
<5
<5
<5
210
<5
320
79
< 10
<5
<5
280
<5
49
<5
44
<5
46
270
<5
<5
74
48
270
<5
14
<5
< 20
< 10
35
350
< 15
2,500
3,000
<5
53
390
6,300
15,000
14
<5
220
<5
330
<5
N/A
<5
7.7
< 10
<5
<5
<5
130
<5
65
51
< 10
<5
<5
19
<5
42
<5
14
<5
29
210
<5
<5
28
28
61
<5
<5
<5
< 20
< 10
25
<5
< 15
1,700
2,100
<5
6.1
250
< 50
12,000
10
<5
56
<5
200
<5
N/A
<5
<5
< 10
<5
<5
<5
76
<5
16
58
< 10
<5
<5
<5
<5
46
<5
11
<5
25
220
<5
<5
18
20
19
<5
<5
<5
< 20
< 10
12
<5
< 15
1,600
1,800
<5
13
< 100
< 50
1,700
10
<5
< 20
<5
<5
<5
N/A
<5
<5
< 10
<5
13
<5
<5
<5
<5
17
< 10
<5
<5
<5
<5
29
<5
13
<5
6.4
160
<5
<5
<5
<5
< 10
<5
<5
<5
< 20
< 10
< 10
<5
< 15
630
840
<5
8.7
< 100
< 50
160
6
<5
< 20
<5
<5
<5
N/A
<5
<5
< 10
<5
<5
<5
15
<5
<5
10
< 10
<5
<5
<5
<5
24
<5
9.9
<5
2.8
120
<5
<5
<5
<5
< 10
<5
<5
<5
< 20
< 10
< 10
<5
< 15
470
680
S7
Increasing Treatment1
Target Compound
Ambient
Chlorinated
Tertiary
Effluent
Ambient
Secondary
Effluent
Ozonated
Secondary
Effluent
O3:TOC=0.262
Ozonated
Secondary
Effluent
O3:TOC=0.502
Ozonated
Secondary
Effluent
O3:TOC=1.002
Ozonated
Secondary
Effluent
O3:TOC=1.502
Isobutylparaben
<5
<5
<5
<5
<5
<5
Isoproturon
< 100
< 100
< 100
< 100
< 100
< 100
Ketoprofen
9.3
8.5
<5
<5
<5
<5
Ketorolac
9.1
13
<5
<5
<5
<5
Lidocaine
140
150
41
12
<5
<5
Lincomycin
< 10
< 10
< 10
< 10
< 10
< 10
Linuron
<5
<5
<5
<5
<5
<5
Lopressor
120
240
140
93
< 20
< 20
Meclofenamic Acid
<5
<5
<5
<5
<5
<5
Meprobamate
170
190
160
140
74
51
Metazachlor
<5
<5
<5
<5
<5
<5
Methylparaben
< 20
< 20
< 20
< 20
< 20
< 20
Naproxen
100
64
28
42
< 10
< 10
Nifedipine
< 20
< 20
< 20
< 20
< 20
< 20
Norethisterone
<5
<5
<5
<5
<5
<5
Oxolinic Acid
<5
<5
<5
<5
<5
<5
Pentoxifylline
<5
<5
<5
<5
<5
<5
Phenazone
<5
<5
<5
<5
<5
<5
Phenytoin
150
160
97
82
< 20
< 20
Primidone
120
440
250
220
55
19
Progesterone
<5
<5
<5
<5
<5
<5
Propazine
<5
<5
<5
<5
<5
<5
Propylparaben
<5
<5
<5
<5
<5
<5
Quinoline
<5
<5
<5
<5
<5
<5
Simazine
7.6
8.1
6
5.4
<5
<5
Sucralose
15,000
17,000
9,900
9,900
7,000
5,500
Sulfachloropyridazine
<5
<5
<5
<5
<5
<5
Sulfadiazine
<5
<5
<5
<5
<5
<5
Sulfadimethoxine
<5
9.4
<5
<5
<5
<5
Sulfamerazine
<5
<5
<5
<5
<5
<5
Sulfamethazine
5.1
5.8
<5
<5
<5
<5
Sulfamethizole
<5
<5
<5
<5
<5
<5
Sulfamethoxazole
320
740
170
62
<5
<5
Sulfathiazole
<5
<5
<5
<5
<5
<5
TCEP
140
110
100
93
100
100
TCPP
820
740
650
660
690
600
TDCPP
630
330
360
350
420
360
Testosterone
<5
<5
<5
<5
<5
<5
Theobromine
120
250
82
68
<5
15
Theophylline
< 10
31
18
23
19
11
Triclosan
12
63
16
< 10
< 10
< 10
Trimethoprim
39
84
16
<5
<5
<5
Warfarin
<5
<5
<5
<5
<5
<5
1
Arrows point in both directions because the ambient secondary effluent is used as the baseline. The arrow to the
left represents any potential reduction in concentration due to chlorination. The arrow to the right represents any
potential reduction to due ozonation.
2
These are the actual concentrations reported by the contract laboratory. TOrC concentrations for the ozonated
samples were not adjusted to account for dilution effect from ozone spike. However, the ambient values are the
true concentrations for those matrices. The ambient values must be adjusted for any relative calculations.
S8