Characteristics and Practice. Ozone & Perozone. In Situ Chemical Oxidation Workshop The 25th Annual International Conference on

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1 Ozone & Perozone Characteristics and Practice William B. Kerfoot Kerfoot Technologies, Inc. In Situ Chemical Oxidation Workshop The 25th Annual International Conference on Soils, Sediments and Water University of Massachusetts, Amherst October 21, 2009

2 C-Sparge (microbubble ozone) O 3 + 2H + + 2e O 2 + 2H 2 O Clean by-products Perozone (peroxide-coated ozone) 2O 3 + H 2 O 2 2OH + 3O 2 Clean by-products How effective are the oxidants? Over 850 installations in Europe and the United States Over 80% of sites have been cleaned up in less than 3 years Perozone has shown capacity for cleanup in periods of months Chemical reaction of Perozone releases twice the hydroxyl radicals per mole of peroxide than Fenton s Reagent

3 Equipment & Processes

4 States Where Ozone is Being Used for In-situ Remediation Approved

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6 Oxidant Price per cubic yard of soil ($) Cost Price $/ton Cost Price $/kg* Type Fenton s reagent % solution Ozone/peroxide (Perozone ) 1 10 plume method source method gas/liquid Ozone gas Permanganate % solution Oxidant Price per m 3 of soil ( ) Cost Price /kg* Type Fenton s reagent % solution Ozone/peroxide (Perozone ) 2 20 plume method source method gas/liquid Ozone gas Permanganate % solution *kg of contaminant weight From: ISCO, In-Situ Chemical Oxidation, SKB, Netherlands Centre for Soil Quality Management and Knowledge Transfer, Gouda, Netherlands

7 % % CHLORINATED 8 20 PETROLEUM INDUSTRIAL 1 5 OTHER 3 5 MEAN 1.82 yrs MEDIAN 2.0 yrs (%) CHLORINATED PETROLEUM INDUSTRIAL OTHER

8 Advantages of Ozone with Petroleum Hydrocarbons Incremental decrease in cost/high % closure/ virtually no rebound Oxygen delivery 15 kg total oxygen per point per day Sources: 20% O 2 in air, ozone, and peroxide Compatible with biological activity Treats recalcitrant compounds TPH alkanes, alkenes MTBE oxygenates PAHs naphthalene TBA alcohols TCA/DCA - chloroalkanes 1,4 Dioxane

9 Mass Removal Site Management Program Improves efficiency reduces time-to-treat Converts aqueous to adsorbed equivalents Recalculates oxidant mass needed per Spargepoint Computes time-to-treat per point Discloses migratory or secondary sources by mass balance

10 Radius of Influence of Sparge Wells The radius of influence was calculated from critical pressure to induce flow, a function of line and point losses, hydraulic head, and formation loss. Field and analytical screening indicates that these may represent minimums.

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13 Ozone Sparging Treatment 100 $ $50 Currently $10-$15 per cubic yard $20 Removal Cost Per Cubic Yard ($) $5 -? Time

14 Bubble Configuration Methyl-tert-butylether MTBE H CH 3 H C O C CH Solubility Henry's Constant H CH 3 3 (Membrane phase) OH Adsorption H 2 O 2 Stripping OH O 2 OH O 2 H Gas phase O 2 2 OH C O 2 2 Aqueous (groundwater) Adsorption Solubility Extraction/reaction Incoming Henry sconstant Outgoing Hydroxyl radical plus dissolved ozone CO 2 O 2 Solid (sediment soil)

15 Criegee Mechanism of Reaction

16 Perozone Type Reactions Peroxide Ozone Hydroxyl Radical Oxygen H 2 O 2 + 2O 3 2HO + 3O 2 + Complex Set of Side Reactions Ozone Hydrogen Superozone Hydroperoxide Peroxide Anion Anion Radical O 3 + HO 2 O 3 + HO 2 Superozone Hydrogen Hydrogen Trioxide O 3 + H + HO 3 Aieta, et al., 1988

17 Nano to Microbubble Production

18 Oxidation Potentials Oxidants vs. Contaminants O3 (molecular) O3 (gas) Fentons Reagens Perozone H2O2 Available Oxidants : Aromatics (poly). e.g. PAH : Aromatics (mono). e.g. BTEX C=C: Alkenes e.g. Chloroethenes C-H: Alkanes e.g. Mineral Oil MnO4 O2 Oxidation Potential (V)

19 Ozone Stability In Gas or Water Phases Ozone can react with NAPL and dissolved or adsorbed contaminants. The gas phase half life may be the controlling reaction; note that the liquid phase half-life is very short since it reacts with water to form hydroxyl radicals as shown on the following slide. Contact is needed between ozone and the contaminant or reactant. Typical O3 half-life vs. Temperature Gaseous Temp (C) half-life * months days days 20 3-days hours seconds Dissolved in Water (ph 7) Temp (C) half-life minutes minutes minutes minutes 35 8-minutes (R. Brown, 2005)

20 Pulsing Necessary to move fine bubbles through soil capillaries Effective transport of liquid Improves contact Avoids channelizing Produces fine bubbles (Kerfoot, 1999)

21 Delivery Systems Multiple Single Points Dual Points Recirculation Wells

22 Receptivity of contaminants toward oxidants Summarized based on OVAM (2004), XDD and Osgerby (2006) Contaminant MnO4 SO4 Fenton's (Per)ozone Saturated Hydrocarbons Petroleum Hydrocarbons (alkanes) P G G E Chlorinated Ethanes P P/M P/M P/G MTBE G G G G Unsaturated Hydrocarbons Chlorinated Ethenes E E E E Monocyclic Aromatics BTEX P/E E E E Chlorinated Phenols G E E E Energetics (RDX, HMX) E E E E Polycyclic Aromatics Polycyclic Aromatic Hydrocarbons (PAH) G E E E Polychlorinated Biphenyl's (PCB's) P P P G Pesticides M G M M/E P = poor, M = moderate, G = good, E = excellent Verhoeve Milieu

23 Fuel Spills MTBE, TBA, BTEX, Naphthalenes, Methylbenzenes, EDB Recent Note: Perozone counteracts hexchrome formation

24 Observed removal rates, efficiencies and stoichiometry. Authors Aqueous phase Treatment Rate of Efficiency Mass ratio (µg/l) volume removal (t1/2) O3/MTBE Start End (m 3 ) (days) (%) (g/g) Kerfoot, W.B. & LeCheminant, P. (2001,2003) 6,000 <70 3, Nichols, E.M. & Voci. C.J. (pilot- 2001) 6,300 <10 2, Wheeler, K.P. (2001) 100,000 4,400 1, Ralston, E. (2001) 4,900 <45 4, (1) Manhart, C & Watt, C. (2003) 10,000 <100 9, Purchase, et. al. (2005) 5, , Kellar, E. (2006) Perozone 7,700 (2) 45 8, (1) Estimated (no soil samples) (2) Total VOCs

25 Case study: C-Sparge TM at a California Site Description site Active bulk fuel and cardlock facility (source: 7 USTs) Site is remodeled to include retail islands and a convenience store Topography : flat (50 m above MSL) Soil characteristics: Fill : m bgl sandy silt : m bgl silty sand (w/ clay) : m bgl Groundwater table : 1.8 m bgl Hydraulic conductivity : 10-3 cm/sec (=1 m/day) Groundwater flow: 0.1 m/day S to SW

26 Site Area C-Sparger -system: 5-15 g O 3 /hr Pilot test (2001): 3 Spargepoints Full-scale ( ): 11 Spargepoints

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28 MtBE in Groundwater (initial) Max. concentrations at begin pilot test: MtBE: µg/l TBA: 870 µg/l

29 Layout of the Full-Scale System Pilot area

30 Pilot test: results field measurements (2) DO against distance from SP Estimated ROI Observed ROI Concentration (mg/l) Distance from SP (m)

31 Full-Scale Remediation: MtBE Decay Curve Pilot test MtBE decay curve of MW-1 and MW-6 From pilot test until site closure Full-scale remediation Site closure MW-1 MW-6 Concentration MW-1 (µg/l) Concentration MW-6 (µg/l) Date

32 Full-Scale Remediation: TBA Decay Curve Pilot test TBA decay curve of MW-1 From pilot test until site closure 600 Full-scale remediation Site closure Concentration (µg/l) Date MW-1

33 #6 Fuel Oil & VOCs Spill (Brownfield)

34 Plume Characteristics Plume Characteristics Major sources dry cleaner chlorinated solvents (PCE), USTs (bunker oil) Contaminated unsaturated zone limited Contaminated aquifer 240 ft x 240 ft x 20 ft deep 42,667 cubic yards Maximum concentrations PCE 4,400 ug/l TPH 30,000 ug/l

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36 Spargepoint Installation

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38 Outcome Class A-2/RAO Closure - Groundwater Start End Removal PCE 3,000 <560 >81% TCE 69 <11 >84% MA VPH Aliphatics C5-C8 800 <20 >98% Aromatics 12,000 <370 >97% MA EPH Aliphatics C9-C18 6,000 <20 >99%

39 MCP S-1 Soil Standards After Treatment (mg/kg or ppm) Standards Sept-Oct 02 Aliphatics C5-C8 C9-C Aromatics C9-C Ethyl-benzene M,P-Xylenes 1000 BRL (10) O-Xylene 500 BRL (10) Naphthalene 4 BRL (.1) PCE 0.5 BRL (.1) TCE 0.4 BRL (.1)

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41 VOCs Chloroethenes PCE, TCE, DCE, VC Chloroethanes 1,1,1-TCE, DCA, CE, CTC, MC Cyclic Aromatics BTEX, PAHs (C 6 to C 30 ) Alkanes/Alkenes (C 4 to C 40 )

42 Federal Superfund Site Federal Superfund Site TCE and cis 1,2-DCE in groundwater ( mg/l) Approximately 15,000 square foot treatment area (100 x 150 ) Aquifer 35 thick (water table 15 bgs) Appalachian Piedmont Province Saprolite Soils (Silty fine sands) Hydraulic conductivity (approx. 5 x 10 4 cm/sec) Seepage velocity (approx ft/yr) RMT, Inc.

43 Federal Superfund Site Spring 2001: Field Pilot Study - 2 sparging wells 50% reduction in TCE, DCE in 12 weeks : Full-Scale design and construction 9 Ozone sparging wells with recirculation capability Air/ozone supply at 2-3 cfm per well, ppm ozone October 2002: System startup RMT, Inc.

44 Ozone Sparging Layout and Initial CVOC Plume TCE > MCLs Cis, 1-2 DCE > MCLs RMT, Inc.

45 Federal Superfund Site October Months of Treatment All monitoring points < MCLS except one 7 of 9 sparge wells turned off May Months of Treatment Remaining monitoring point achieved cleanup goals No rebound effect observed in other site areas Entire system turned off RMT, Inc.

46 CVOCs after 3-Months of Treatment CVOCs after 3-Months of Treatment RMT, Inc.

47 CVOCs after 12-Months of Treatment CVOCs after 12-Months of Treatment RMT, Inc.

48 Federal Superfund Site cis 1,2-DCE RMT, Inc. Oct-02 Dec-02 Feb-03 Apr-03 Jun-03 Aug-03 Oct-03 Dec-03 Feb-04 Apr-04 Concentration (ug/l)

49 Federal Superfund Site TCE RMT, Inc. Oct-02 Dec-02 Feb-03 Apr-03 Jun-03 Aug-03 Oct-03 Dec-03 Feb-04 Apr-04 Concentration (ug/l)

50 Wood Preservatives Chlorophenols PCP, TCP, CP Creosote Naphthalenes Cresols

51 Site Conditions Historic lumber mill ( ) with former chlorophenol release. ~20 kg of sorbed (~100 mg/kg) and dissolved (~20 mg/l) PCP remained. Two distinct sources with plume extending 200 feet down-gradient. Plume intercepted by storm drain. Hydraulic gradient reversed by leaking water line.

52 Ozone and Peroxide Injection Mass 60 15% H 2 O % H 2 O 2 15% H 2 O % H 2 O 5% H O 2 Gallons of Peroxide (H O 2 2 ) injected ;100% Equivalent Ozone injected (Kg) /19/2004 1/28/2004 2/6/2004 2/15/2004 2/24/2004 3/4/2004 3/13/2004 3/22/2004 3/31/2004 4/9/2004 4/18/2004 4/27/2004 5/6/2004 5/15/2004 5/24/2004 6/2/2004 6/11/2004 6/20/2004 6/29/2004 7/8/2004 7/17/2004 7/26/2004 8/4/2004 8/13/2004 8/22/2004 8/31/2004 9/9/2004 9/18/2004 9/27/ /6/ /15/ /24/ /2/ /11/2004 * Note: Horizontal slopes represent time periods of no peroxide injection. ** 5% -- percent by volume of H 2 O 2 injected for respective time period. DATE Peroxide Injection Ozone Injection 0

53 Chloride Ion/PCP Time Series PCP Concentration Trendline PCP (µg/l) Chloride (µg/l) WQO Reached June /19/04 2/13/04 3/31/04 4/21/04 5/26/04 6/28/04 7/19/04 8/16/04 9/30/04 12/1/04 12/20/04 12/29/04 12/29/04 2/12/05 3/29/05 5/13/05 6/27/05 Chloride (µg/l) PCP (µg/l) Water Quality Objective (WQO) for PCP:

54 Oxidation Processes 260 kg (O 3 + H 2 O 2 ) oxidant injected kg O 2 as air injected kg organic carbon mineralized. 12 kg chlorophenols mineralized. 150 kg of carbonate reacted.

55 Pesticides Orthochlorinated Series Chlordane Heptachlor Aldrin Dieldrin HCH Precurser MECOPROP DDT/DDD

56 Case study: Biddinghuizen site (pilot test) Site description Industrial site Groundwater contamination with MCPP (common name: Mecoprop): max. 580 µg/l before pilot test Area : app m 2 Depth : until app. 8 m bgl Soiltype: 0-1,3 m bgl : sandy topsoil 1,3-2,3 m bgl : clay 2,3-8 m bgl : fine sand 8,0-15 m bgl : medium to coarse sand Watertable : 2,0 m -bgs Verhoeve Milieu

57 Properties of MCPP Common name : Mecoprop (acid herbicide) Chemical name : 2-(4-chloro-2-methylphenoxy)- propionic acid Molecular formula : C 10 H 11 ClO 3 Molecular weight : g/mole Structural formula: A benzene derivative Vapour pressure : 1,6 x 10-3 Pa (25 C) (non-volatile) Henry s constant : 2,18 x 10-4 Pa m 3 /mol (non-strippable) Waste water treatment: effective degraded using a combination of ozone and hydrogen peroxide Verhoeve Milieu

58 Pilot Unit Perozone Total mass of oxidant injected within injection triangle : Ozone : 16 kg Peroxide: 66 kg Operation pilot test: Run time : 58 days Flowrate air/ozone : 5-15 Nm3/hr Ozone loading : g O3/hr Flowrate peroxide : 4 l/hr (7W%) Peroxide loading : 0,3 kg/hr (100 W%) Verhoeve Milieu

59 Development total mass during pilot test Mass development MCPP 250 Mobilization Closure pilot test Total mass (%) Time (days) Verhoeve Milieu Total mass (%) Overall removal of 87% in 9 weeks of treatment