Removal of Bromate and Perchlorate in Ozone/GAC Systems

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• To investigate the mechanism of the biological reduction process, with special focus on the role of nitrate-reducing organisms, the types of microorganisms carrying out the bromate/perchlorate reduction and their growth requirements, the type and concentration of electron donor, and the effect of parameters such as bromate and perchlorate concentration, dissolved oxygen (DO) concentration, nitrate concentration, pH, temperature, and the role of a prefiltration ozonation step. To investigate advanced oxidation processes to determine whether these reactions can produce efficient removal of perchlorate, and if so, to develop the process at the bench-scale. *• Emphasis will be placed on the ozone-hydrogen peroxide-GAC process, virgin GAC, GAC impregnated with metals such as copper and zinc, and GAC mixed with solids such as iron, zinc, and aluminum. To optimize the bromate and perchlorate removal processes that show the most encouraging results and to monitor the product water for potability. To test the most promising of the bromate and perchlorate removal processes at the pilot- scale. 18
CHAPTER 2. MATERIALS AND METHODS MATERIALS USED FOR BROMATE REDUCTION EXPERIMENTS Water Deionized, distilled water (DDW) had a total organic carbon concentration less than 0.3 mg/L. Champaign-Urbana, tap water (CUW) and Lake Michigan water (LMW) were the two natural waters used in this study. CUW is tapwater (Champaign, Illinois), and it comes from a groundwater source. Prior to use, CUW was dechlorinated by sodium sulfite addition. Raw LMW was obtained from the crib of the South Water Production Plant (Chicago, IL); the crib is 3.2 kilometers (2 miles) from shore at a depth of 9.6 to 10.5 meters (32-35 feet). The main differences between the two natural waters were the ammonia (NH3) concentrations and biodegradability of the organic matter. CUW contained less than 1.70 mg/L NH3-N, with an average concentration of 0.80 mg/L, and the NH3-N concentration in LMW was below the detection limit of 0.05 mg/L. The ammonia in CUW led to the production of nitrate in the BAG filters; little or no nitrification occurred in LMW, and the background nitrate concentration was 1.6 mg/L. The organic matter in CUW displayed some degree of biodegradability in the BAG filter, with an average dissolved organic carbon (DOC) removal of 25 percent. The organic matter in LMW was fairly inert in the BAG filter with an average DOC removal of 4 percent. Average water characteristics of CUW and LMW are listed in Table 2.1. Table 2.1 Average water quality characteristics of CUW and LMW Water Chloride Nitrate Sulfate DOC Ammonia (mg/L) (mg/L) (mg/L) (mg/L) (mg/LN) CUW 8 0.3 1 1.4 0.80 LMW 10 1.6 23 2.4
Page 1: AWWA Research Foundation Removal of
Page 4 and 5: The mission of the AWWA Research Fo
Page 6 and 7: Disclaimer This study was funded by
Page 8 and 9: Serum Bottle Experiments ..........
Page 11 and 12: TABLES 1.1 Bromate removal in DFE a
Page 13 and 14: FIGURES 1.1 Effect of influent diss
Page 15: 3.32 Perchlorate removal vs. nitrat
Page 18 and 19: Perchlorate and chlorate salts are
Page 21 and 22: EXECUTIVE SUMMARY Bromate (BrO3~) a
Page 23 and 24: scale ozone-BAC plants is likely du
Page 25 and 26: RECOMMENDATIONS 1. To utilize BAG f
Page 27 and 28: CHAPTER 1. INTRODUCTION BACKGROUND
Page 29 and 30: PREVIOUS STUDIES - BROMATE 1 Siddiq
Page 31 and 32: ethanol was required to stimulate e
Page 33 and 34: were not measured, they can be pres
Page 35 and 36: one year prior to this experiment,
Page 37 and 38: 2.0 - e • • 8 i 8 a
Page 39 and 40: i S I i.o - 1.4 - 1.2 - 1.0 - 0.8 -
Page 41 and 42: ut the concentrations of oxygen and
Page 43: species that is able to reduce perc
Page 47 and 48: BAG was formed by extensively prelo
Page 49 and 50: Floating Cover 1 Influent: LMW 20 (
Page 51 and 52: Backwash ing the BAG filters Two of
Page 53 and 54: Table 2.2 Agar recipe for plating e
Page 55 and 56: Streaked individual colony morpholo
Page 57 and 58: METHODS UTILIZED FOR PERCHLORATE RE
Page 59 and 60: Metal-Catalyzed GAG Filter Experime
Page 61 and 62: perchlorate, nitrite, nitrate, and
Page 63 and 64: Table 2.5 Serum bottle experiment 2
Page 65 and 66: CHAPTER 3. RESULTS AND DISCUSSION B
Page 67 and 68: a two-week period. Over the two-wee
Page 69 and 70: To establish the effect of backwash
Page 71 and 72: o S 25 20 - 15 - 10 - O 50-min EBCT
Page 73 and 74: In general, the average percent bro
Page 75 and 76: measured nitrate concentration and
Page 77 and 78: Two data points in each of Figures
Page 79 and 80: 90 - ^ 80 - 70 - J 60 - o 11 1 50 -
Page 81 and 82: ench-scale and full-scale B AC filt
Page 83 and 84: omate removal was sustained (Figure
Page 85 and 86: Fraction Perchlorate Remaining, Fra
Page 87 and 88: Figure 3.18 Rods and cocci from the
Page 89 and 90: seen that the BAG samples contain a
Page 91 and 92: Bromate Reduction in DDW with Exoge
Page 93 and 94: The mass balance on nitrate + nitri
Page 95 and 96:
N2O was not detected and no evidenc
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Table 3.10 Results of dilution-to-e
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0 so o U ).0 - I 5.0 U ffl Addition
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o I Io U D o ou - 50 1 40 - 30 - 20
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Wash Tests Table 3.11 lists the res
Page 105 and 106:
The next step was to determine if p
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Jar cio4- 42.8 40.4 40.5 41.1 6 C/C
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of nitrate on perchlorate reduction
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Effluent Perchlorate, C/C l.U 0.8 -
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was decreased. It is interesting to
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1 1.6 1.4 - 1.2 - .1.0- 1.5mg/L Inf
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or 1.5 mg/L nitrate showed no perch
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^——s 0 4 0 234 Incubation Time
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Figure 3.43 illustrates the differe
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Figure 3.44 Rods and protozoa from
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CHAPTER 4. ACTIVITIES AT THE METROP
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Perchlorate is only found in CRW, a
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Residual ozone. To reduce sample ov
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^ influent 0 effluent A mid • inf
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Effect of Nitrate The background ni
Page 135 and 136:
Table 4.2 Control study for chemica
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PILOT-SCALE MOBILE PILOT PLANT STUD
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Mobile Pilot Plant Ozone The ozonat
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Table 4.4 Mobile pilot plant operat
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p o O. i Fraction Bromate Remaining
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CHAPTER 5. SUMMARY AND CONCLUSIONS
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Bromate removal increased as the in
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virgin Norit GAC showed an ion exch
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Microscopic examination of the biom
Page 153:
CHAPTER 6. RECOMMENDATIONS TO UTILI
Page 156 and 157:
Brock, T. D., M. T. Madigan, J. M.
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Kirisits, M. J., V. L. Snoeyink, an
Page 160 and 161:
Rogers, K. 1997. Water Contaminated
Page 163 and 164:
ABBREVIATIONS AWWA AWWARF American
Page 166:
AWWA Research Foundation Advancing
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Removal of Bromate and Perchlorate in Ozone/GAC Systems

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