CARUS REMEDIATION TECHNOLOGIES

Transcription

1 CARUS REMEDIATION TECHNOLOGIES In Situ Chemical Oxidation (ISCO) Prepared by: Dr. Ing. Lorenzo Sacchetti CRT Director Europe, Middle East and Africa

2 The Science The Basic Premise: Inject an oxidizing agent into a contaminated zone in order to chemically break the carbon bond converting the contaminant from a toxic compound to naturally occurring non- hazardous compounds.

3 What is In Situ Chemical Oxidation? Distribution Reagent load Success is enough oxidant (reducer) in contact with the contaminant for a long enough period of time to react effectively Reagent persistence Contaminant Destruction

4 What is In Situ Chemical Oxidation? The art of achieving contact between the oxidizing agent and the contaminant Choosing the correct reagent Choosing the correct delivery mechanism Understanding the site specific oxidant demand Creating contact

5 What is In Situ Chemical Oxidation? In its simplest sense ISCO remains a contact process requiring the oxidant to physically contact the contaminant: Contact = Reaction (hopefully) Success ( potentially ) No Contact = No Reaction Failure ( definitely! ) Contact is facilitated by a variety of methods and techniques

6 Where to apply ISCO ISCR GW Flow Dissolved Plume Area 10% Mass Core Plume Area 10% Mass Source Area 80% Mass 75% Plume Size 20% Plume Size 5% Plume Size Bioremediation, Natural Attenuation, ISCO-ISCR (speed only) ISCO - ISCR, BioRemediation, Pump & Treat Dig and Haul, Thermal, ISCO - ISCR

7 The Oxidants. Permanganate RemOx S and RemOx L MnO4- + 4H+ + 3 e- MnO2 + 2 H2O Fenton H2O2 + 2H+ + 2e- 2 H2O 2 OH + 2H+ + 2e- 2 H2O HO2 + 2H+ + 2e- 2 H2O O2- + 4H+ + 3e- 2 H2OHO2- + H2O + 2e- 3 OH- Ozone O3 + 2H+ + 2 e - O2 + H2O 2 O3 + 3H2O2 4 O2 + 2 OH + 2 H2O Persulphate OBC S2O e - 2 SO4 SO4- + e - SO4 1.7 V (permanganate ion) 1.8 V (hydrogen peroxide) 2.8 V (hydroxyl radical) 1.7 V (perhydroxyl radical) 2.4 V (superoxide radical) 0.88 V (hydroperoxide anion) 2.1 V (ozone) 2.8 V (hydroxyl radical) V (persulphate) V (sulphate radical)

8 CoCs and Oxidants - I Hydrogen Peroxide Oxidant and Activation Technique Persulfate Permanganate Chelated iron None* Iron/acid Alkaline ph Iron Chelated iron None Peroxide Light hydrocarbon fuels1 Heavy hydrocarbon fuels2 Creosote, coal tar, MGP residuals, other PAHs PCBs or PBBs3 N/R** N/R N/R N/R Common contaminant mixtures. Dioxins or furans Common specific fuel contaminants and breakdown products Benzene N/R Toluene Ethylbenzene Xylenes (o-, p- or m-) Methyl-tertbutylether (MTBE) Tert-butyl alcohol (TBA) N/R

9 CoCs and Oxidants - II Hydrogen Peroxide Oxidant and Activation Technique Permanganate Chelated iron None* Persulfate Iron/acid Alkaline ph Iron Chelated iron None Peroxide Common chlorinated solvents, stabilizers and their breakdown products Tetrachloroethene (PCE) Trichloroethene (TCE) N/R Dichloroethenes 4 Vinyl Chloride Tetrachloroethanes Trichloroethanes 5 6 N/R Dichloroethanes7 N/R Chloroethane N/R Carbon tetrachloride N/R N/R N/R N/R Chloroform N/R N/R N/R N/R Dichloromethane N/R N/R N/R N/R Methylene Chloride N/R Pentachlorophenol (PCP) Chloro- & Dichlorophenols Chlorobenzene Di and trichlorobenzenes. Chlorinated aromatic contaminants Explosives, energetics and breakdown products RDX and HMX TNT and DNT Di and Trinitrobenzenes Mono and dinitrophenols

10 The Reducers Sodium Bisulphite/Thiosulphate 3NaHSO3 + 2H2CrO4 + 3H2SO4 Cr2(SO4)3 + 5H2O + 3NaHSO4 Zero Valent Iron (ZVI) ABC+ carbon substrate and ZVI. Fe0 Fe2+ + 2eRCl + 2e- + H+ RH + ClFe0 + RCl + H+ Fe2+ + RH + Cl- Anodic Reaction (1) Cathodic Reaction (2) Net Reaction (3) 2Fe0 + O2 + 2H2O 2Fe2+ + 4OH- Water corrosion (4)

11 CoCs and Reducers Zero Valent Iron (ZVI) ABC+ Tetrachloroethene (PCE) Trichloroethene (TCE) cis 1,2-Dichloroethene (cdce) trans 1,2-Dichloroethene (tdce) 1,1-Dichloroethene (11DCE) Vinyl Chloride (VC) Hexachloroethane (HCA) 1,1,2,2-Tetrachloroethane (1122TeCA) 1,1,1,2-Tetrachloroethane (1112TeCA) 1,1,1-Trichloroethane (111TCA) 1,1,2-Trichloroethane (112TCA) 1,1-Dichloroethane (11DCA) Carbon Tetrachloride (CT) Trichloromethane (TCM) Tribromomethane (TBM) 1,2-Dibromoethane (12EDB) Trichlorotrifluoroethane (Freon 113) Trichlorofluoromethane (Freon 11) 1,2,3-Trichloropropane (123TCP) 1,2-Dichloropropane (12DCP) Lindane Hexachlorobutadiene (HCBD) N-nitrosodimethylamine (NDMA)

12 CoCs and Reducers Sodium Bisulphite Hexavalent Chromium Zero Valent Magnesium (Palladium?) DDT DDD DDE PCBs

13 Competing Reactions Oxidant i.e. MnO4- Satisfy Natural Oxidant Inorganic Demand, t½ = seconds. Organic Demand, t½ = min. Target Compound Mineralization 2.4 lb KMnO4 / lb TCE, t½ = 18 min. Soil Matrix Demand (NOD SOD) x CO2 + x MnO2 + x Cl- + H+ 1.3 lb KMnO4 / lb PCE, t½ = 260 min. Not significant for permanganate Oxidant Decomposition 4MnO4- + 4OH- 4MnO H2O + O2 t½ = 10 s of years

14 Evaluation Process What Needs to be Considered Geology Geochemical Concerns Sands Silts Clays Glacial Till Fractured Bedrock Target Contaminants Natural Oxidant Demand Contaminant Phase ph Alkalinity Heavy Metals Oxidant Selection Delivery Mechanisms Sodium Permanganate Potassium Permanganate Hydrogen Peroxide Ozone Sodium Persulfate Fenton s Reagent High or Low Pressure Injection Hydraulic Fracturing Pneumatic Fracturing Recirculation Systems Reactive Barriers

15 Design pathway

16 Evaluation Process How Much Do I Need To Inject? ta a D bo s Re Tr an sit io n M et al f o e Depth g A to Con y tamin tr e ation m o i h c i o ion t a St e n i l e e D f o m y t i l u l a Qu Vo TOC e r Po Tre Number of Injections atm ent Are a Soil Matrix un d o a ls Co en t G P ant min nta e has T re a tm

17 SOD and Calculations for ISCO

18 SOD and Calculations for ISCO CS = Contaminant Concentration in soil (mg/kg) CGW = Contaminant Concentration in groundwater (ug/l) CNPL = Contaminant Concentration in NAPL phase (mg/l) PEb= Effective Porosity G = Gallons Water To Be Treated (X*Y*Z*PE) YS = Yards of Soil To Be Treated (X*Y*Z) S = Stoichiometric requirements per pound of contaminant SOD = Soil Oxidant Demand (g/kg) SODE = Effective Soil Oxidant Demand % SR = Other Scavenging Reactions (g/kg) CF = Confidence Factor (contaminants, lithology, hydrogeology, distribution, contact delivery) TR = Total Pounds of Oxidant required TR = { (CS+CGW+CNPL)*G*S + (SOD*SODE+SR)*Ys}* CF

19 PCE and TCE + Fenton

20 Benzene + Fenton

21 Cloroethenes and RemOx RemOx Permanganate Oxidation of Chlorinated Ethenes + ClPermanganate Ion Complete Mineralization

22 PCE + RemOx 4 KMnO4 + 3 C2Cl4 + 4 H2O 6 CO2 + 4 MnO2 + 4 K Cl- + 8 H+ Stoichiometric Mass Requirements: 1.3 g KMnO4 / g PCE 1.1 g NaMnO4 / g PCE Cl 0 Cl CAS Rn = [ ] Molecular Weight : Cl Cl Melting point: oc Boiling kPa: oc 20oC : g/cm3 Solubility in 20 oc : 150 mg / kg Solubility of water in 20 oc : 80 mg. /kg Ln(PCEt /PCEt=0) PCE Reaction Time, minutes

23 TCE + RemOx 2 MnO4- + C2HCl3 2 CO2 + 2 MnO2 + 3 Cl- + H+ Stoichiometric Mass Requirements: 2.4 g KMnO4 / g TCE 2.2 g NaMnO4 / g TCE Cl Cl CAS Rn = [ ] Molecular Weight : Melting point: oc Cl o Boiling kPa: 86.7 C 20oC : g/cm3 Solubility in 20 oc : %(w/w) Solubility of water in 20 oc : %(w/w) Ln(TCEt/TCE0) TCE Reaction Time, minutes

24 DCE and VC + RemOx DCE 8KMnO4 + 3C2H2Cl2 6CO2 + 8MnO2 + 8K+ + 6Cl- + 8OH+ + 2H2O Weight Ratio: KMnO4 4.4 : 1 NaMnO4 3.9 : 1 VC 10KMnO4 + 3C2H3Cl 6CO2 + 10MnO2 + 10K+ + 3Cl- + 7OH+ + H2O Weight Ratio: KMnO4 8.5 : 1 NaMnO4 7.6 : 1

25 Energetics + Permanganate RDX RDX, an initialism for Research Department Explosive, is an explosive nitroamine widely used in military and industrial applications. It is also known less commonly as cyclonite, hexogen and T4. Its chemical name is cyclotrimethylenetrinitramine; variants include cyclotrimethylenetrinitramine and cyclotrimethylene trinitramine + KMnO4 Methylenedinitramine Hydroxymethylnitramine Formaldehyde Formic Acid Carbon Dioxide

26 RemOx Oxidation Rates k (M-1s-1)* t½(min)** Trichloroethylene 0.65 ± Perchloroethylene ± Cis-dichloroethylene ± Trans-dichloroethylene 30.0 ± ,1-dichloroethylene 2.38 ± * Yan & Schwartz Journal of Contaminant Hydrology ** 158 mg KMnO4/L, KMnO4 in excess

27 RemOx in summary Permanganate Points The utilization of permanganates for ISCO of chlorinated ethenes is a proven and maturing market Single component oxidant not requiring activation Very stable oxidant Persistence allow diffusion into tighter matrixes Reaction is not ph sensitive Lowest carbon footprint for permanganate production in the world

28 OBC activated persulfate OBC Oxygen BioChem is a patented combination of sodium persulfate and food grade calcium peroxide in one product A slow-release oxygen generating formula designed to provide short-term chemical oxidation (1-2 months) and long term anaerobic oxidation via sulfate reduction (1-2 years) Fast oxidation via persulfate radicals Injected, blended or added prior to backfill

29 OBC action scheme Chemical action 1-2 months SO4 - + e- à SO4-2 E0 = ~ 2.6 v CaO2 + H20 à Ca(OH) 2 + H2O2 Biological action up to 2 years SO42- à 2O2 + S2S2- + Me2+ à SMe 29

30 OBC in summary OBC Activated Persulfate Points The utilization of OBC for ISCO is a proven and maturing market for the following contaminats: TPHs (GRO, DRO), MTBE, hydraulic oils, chlorinated solvents pre mixed two components reagent Allows for consequent bioremediation (SRBs) No need for ph control Ideal for mixed contamination

31 MONITORING Contaminants of Concern (CoCs) Metals if required Oxidant ph, RedOx, activators, sulphates (for persulfate) colour (permanganate) On monthly basis for 3 months or on the basis of site specific conditions

32 In Summary Applicability Permeable soils (Contact!!) Vadose (RemOx, OBC, Ozone) Less permeable soils (silt, clay) with fracturing and persistent oxidants (i.e. Permanganate no Fenton) Reactivity with the oxidants/reductants Reasonable NOD-SOD Source areas

33 In Summary Limits Impermeable soils Activation, ph control (not for permanganate, ZVI, bisulphite) Free phase (can be treated by some Fenton, ABC+) Exothermic reactions, gas production, explosions for Fenton

34 Delivery Technologies

35 Simplified Injection

36 Simplified Direct Push Injection

37 Permanganate Injection Equipment

38 Permanganate Injection Equipment

39 Permanganate Injection Equipment

40 Permanganate Injection Equipment

41 Permanganate Injection Equipment

42 Delivery Techniques In Situ Mixing

43 Delivery Techniques In Situ Mixing

44 How To Ensure a Successful ISCO Project Be confident in your site data MIPS or more sampling Inject enough oxidant Know your PNOD Know your goals Establish a sampling plan Make sure there are enough sample locations to prove goals Design for at least two injections Be flexible in the field

45 EUROPE Lorenzo Sacchetti CARUS EUROPE Parque Empresarial de ASIPO - C/ Secundino Roces 3 - Oficina Cayes ( Llanera ) Spain Fax caruseurope@caruscorporation.com USA Kelly Frasco Liz Mueller Laboratories (USA) Pamela Dugan kelly.frasco@caruscorporation.com liz.mueller@caruscorporation.com pamela.dugan@caruscorporation.com

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