Anaerobic Bioremediation of Chlorinated Solvents in Groundwater Using Edible Oil Substrate EOS

Transcription

1 Anaerobic Bioremediation of Chlorinated Solvents in Groundwater Using Edible Oil Substrate EOS Matt Sedor, M.S., Yonathon Yoseph, P.G., C.H.G. (Remediation Sciences, Inc.) Jeff Baker (Vironex, Inc. ), John Sankey, P.Eng. (True Blue Technologies Inc.). Given by John Sankey, P.Eng., True Blue Technologies Copyright 2007True Blue Technologies Inc.

2 lide 2 From this

3 lide 3 to this in 18 months!

4 Anaerobic Bioremediation of Chlorinated Solvents in Groundwater Using Edible Oil Substrate EOS Site Intro Anaerobic Bioremediation Few slides Options: What ferments to hydrogen? Designing the Project Preparing and Injecting Substrate Results Ground Water Characterization--What to Monitor?

5 lide 5 Site Intro: Dry eaners Site Located in San Jose, California Highest PCE and TCE concentrations in the January 2005 were 8,500 µg/l. After evaluating several alternatives, in situ bioremediation was selected. The goal was to find a substrate that was long lasting and easily distributed into the saturated soils.

6 How Does Anaerobic Bio Work? Growth-Promoting Biological Reduction + + Electron Donor (Food) Electron Acceptor (something to breathe) [O 2, NO 3, SO 4, TCE, etc.] Waste Products [CO 2, N 2, FeS 2, - ] Energy (Drawing Modified from AFCEE and Wiedemeier)

7 lide 7 What is Needed for Effective Anaerobic Bioremediation? Organic substrates that ferment to: Acetate Hydrogen (H 2 ) Strongly reducing conditions (Sulfate Reducing or Methanogenic) Right halorespiring bacteria (Dehalococcoides for DCE / VC) Nutrients Vitamins and trace minerals to stimulate Dehalococcoides growth Source: AFCEE, Principles and Practices of Enhanced Anaerobic Bioremediation of Chlorinated Solvents, August 2004

8 OPTIONS: What quickly ferments to hydrogen? Soluble substrates (e.g., lactate, butyrate, propionate, acetate, molasses, and sugars). Solid substrates (e.g., bark mulch, compost, chitin and peat). Slow release substrates such as vegetable oil.

9 lide 9 What lasts longer in-situ? Soybean oil C 56 H 100 O 6 (soybean oil 1 ) + 50 H 2 O -B-> -B-> 28 CH 3 COOH (acetic acid) + 44 H 2 1 Represents weighted average of constituent fatty acids and glycerol.

10 How Many Electrons Can We Pump into the Ground? e - Released per mole per lb Acetate Lactate Glucose Soybean Oil Canola Oil Lard

11 lide 11 Soy/Lactate Emulsions Blender Lab Homogenizer Silverson High Shear Mixer EOS

12 lide 12 The Secret of Good Oil Distribution Emulsions that do NOT Flocculate Dispersed Oil Droplets Flocculated Oil Droplets

13 lide 13 Secrets of Good Emulsion Distribution Use Emulsions that do NOT Flocculate ogged pore

14 lide 14 Technology Choice--EOS Why? Slow release substrate Emulsified soybean oil (GRAS) Small, uniform droplets Negative surface charge Easily biodegradable substrate Lactate Micronutrients Amino acids, Trace nutrients, Vitamins Easy to inject and distributed throughout treatment area Solid reputation Cost

15 lide 15 Technology Choice Proposed Cost EOS598 B42 Cost-6600 lbs $19,000 Drilling 12 points, injected 4,400 gallons of EOS mix and 22,700 gallons of flush water over a period of 6 days. $30,000 Plus monitoring and engineering

16 lide 16 Designing the Injection at The Dry eaner Site You need to make contact with the contaminant

17 lide 17 From This Radius of Influence? 10ft to 100ft with EOS..To This

18 lide 18

19 lide 19 Source Treatment with Barriers Barriers 0.5 to 1 year apart Advantages Low cost Fewer injection points Less oil and water Release of TOC enhances downgradient biodegradation Aquifer remains permeable Disadvantage Longer clean-up time Groundwater Flow

20 lide 20 Source Area Treatment

21 lide 21 How much do we inject?

22 lide 22 Treatment Zone Dimensions X Barrier EOS Emulsion & Chase Water y Source Area Treated Groundwater Make barrier wider than plume width X Source Area Injection Point y Groundwater Flow z

23 lide 23 Design Tool Used Substrate needed for biodegradation Flow rate through barrier Pollutant concentrations Competing electron acceptors (O 2, NO 3, SO 4 ) Theoretical substrate life (5 to 10 years) Oil retention by aquifer Higher retention with fine grained materials Emulsified Edible Oil Source Design Software Beta Version Site Name: Location: Project No.: Section A: Treatment Area Dimensions Groundwater Flow Length of source area parallel to groundwater flow, "x" 50 ft 15.2 m Width of source area perpendicular to groundwater flow, "y" 50 ft 15.2 m EOS Emulsion & Chase Water Minimum depth to contamination 5 ft 1.5 m Maximum depth of contamination 50 ft 15.2 m y Source Treated Groundwater Treatment thickness, "z" 45 ft 13.7 m Area Treatment zone cross-sectional area = y * z 2,250 ft m 2 Groundwater Flow Rate/ Site Data X Source Area y Soil Characteristics Nominal Soil Type (enter clay, silt, silty sand, or sand) sand Injection Point Hydraulic Characteristics Total Porosity (accept default or enter n ) 0.38 (decimal) z Effective Porosity (accept default or n e ) 0.29 (decimal) Hydraulic Conductivity (accept default or enter K ) 28.5 ft/day 1.0E-02 cm/sec Hydraulic Gradient (accept default or enter i ) ft/ft Non-reactive Transport Velocity (V x) ft/day m/day Groundwater flowrate through treatment zone (Q) gallons/day L/day Calculated Contact Length (x) = C t * V x Contact time (C t) between oil and contaminants (accept default or enter C t) 60 typical values 30 to 90 days, see comment Calculated Contact Lenght (x) = Ct * V x ft 3 2 Treatment zone volume 135,000 ft 3,186 m Treatment zone groundwater volume (volume * effective porosity) 292,842 gallons 923,837 L Design Lifespan For One Application 10 year(s) typical values 5 to 10 years Total groundwater volume treated over design 9,046,546 gallons 34,062,512 L life Electron Acceptors Stoichmetry Hydrogen GW Conc. MW e - equiv./ Inputs Typical Value Contaminant/H 2 Demand (mg/l) (g/mole) mole (wt/wt H 2 ) (g H 2 ) Dissolved Oxygen (DO) 0 to Nitrate Nitrogen (NO 3 - N) 1 to Sulfate (SO 2-4 ) 10 to Tetrachloroethene (PCE), C Trichloroethene (TCE), C 2H cis-1,2-dichloroethene (c-dce), C 2H Vinyl Chloride (VC), C 2H Carbon tetrachloride, C Chloroform, CH sym- tetrachloroethane, C 2H ,1,1-Trichloroethane (TCA), CH 3C ,1-Dichloroethane (DCA), CH 2CH Chloroethane, C 2H Perchlorate, O Hexavalent Chromium, Cr[VI] User added User added User added Additional Hydrogen Demand and Carbon Losses Hydrogen DOC GW Conc. MW e - equiv./ Stoichmetry Generation (Potential Amount Formed) Typical Value Demand Released (mg/l) (g/mole) mole Contaminant/H 2 (g H 2 ) (moles) (wt/wt H 2 ) Estimated Amount of Fe2 + Formed 10 to

24 lide 24 Determining Injection Well Spacing Tradeoff between Well installation cost Labor cost for injection Material cost for emulsion Cost per ft barrier ($/ft) Cost per ft barrier ($/ft) Cost / Ft of 30 Ft Deep Barrier Total EOS Well Spacing Wells Labor Cost / Ft of 100 Ft Deep Barrier Total EOS Well Spacing Wells Labor

25 lide 25 Enhanced Anaerobic Bioremediation Using Emulsified Edible Oils Preparing and Injecting Emulsions

26 lide 26 Injection System Design Options Direct-push technology Using pressure Injection wells Gravity feed Low pressure

27 lide 27 Emulsion Dilution Options Continuous injection of dilute emulsion without chase water Dilution ratios range from 1:10 to 1:30 Depends on effective porosity Injected 4,400 gallons of EOS mix and 22,700 gallons of chase water Chase water used to distribute emulsion out into the formation

28 lide 28 Emulsion Dilution In-line metering system Continuous Metering System Eliminates labor and equipment for field blending Adjustable dilution ratio

29 Ground Water Characterization What to Monitor Indicator Parameters Electron acceptors (O 2, NO 3, SO 4 ) Low levels of O 2 are not a major problem High levels of SO 4 increase substrate demand Electron donors (Mn, Fe, CH 4, TOC) ORP, PH Degradation products See EPA / AFCEE protocol for MNA of Chlorinated Solvents

30 Degradation products CC HH CC 1,1-DCE HH CC CC PCE ee TCE CC CC HH HH HH CC CC CC CC HH HH cis-1,2 1,2-DCE trans-1,2 1,2-DCE HH HH HH HH CC CC CC CC HH HH HH Vinyl Chloride Ethene H 22 H + + Electron Flow Complete Mineralization HH H HH CC CC HH H HH Ethane OO CC OO OO CC OO (Drawing Modified from AFCEE, Technology Transfer Division)

31 lide 31 Anaerobic Bioremediation of Chlorinated Solvents in Groundwater Using Edible Oil Substrate EOS Results

32 lide 32 PLUME OF THE MAJOR CONTAMINANTS Pre-Injection (injection April 2005)

33 lide 33 PLUME OF THE MAJOR CONTAMINANTS 6-months post-injection

34 lide 34 PLUME OF THE MAJOR CONTAMINANTS 9-months post-injection

35 lide 35 PLUME OF THE MAJOR CONTAMINANTS 12-months post-injection

36 lide 36 PLUME OF THE MAJOR CONTAMINANTS 15-months post-injection

37 lide 37 PLUME OF THE MAJOR CONTAMINANTS 18-months post-injection

38 RESULTS: CHART 1: MW-1A ANALYTICAL RESULTS VERSES TIME Concentration (micromoles/liter) Volatile Organic Compounds /21/2002 1/27/2005 7/14/ /26/2005 1/18/2006 PCE (micromoles/l) Cis -1, 2-DCE (micromoles/l) Date TCE (micromoles/l) Vinal Chloride (micromoles/l) TOC Concentration (mg/liter) MW-1A Total Organic Carbon (TOC) and Dissolved Oxygen (DO) /21/2002 1/27/2005 7/14/ /26/2005 1/18/2006 Date TOC (mg/l) DO (mg/l) DO Concentration (mg/liter) Methane, Ethane, and Ethene Oxygen Reduction Potential (ORP) and ph Concentration (millimoles/liter) ORP (millivolts) ph 0 5/21/2002 1/27/2005 7/14/ /26/2005 1/18/2006 Date /21/2002 1/27/2005 7/14/ /26/2005 1/18/2006 Date Methane (millimoles/l) Ethane (millimoles/l) Ethene (millimoles/l) ORP (mv) ph

39 lide 39 Project Conclusions EOS effectively distributed throughout treatment area Quickly established favorable geochemistry for reductive dechlorination. Dramatic improvements in groundwater conditions compared to prior technologies Substantial reductions in TCE observed. Apply for decrease monitoring to every 6 months. Apply for closure this year.

40 lide 40 I would like to thank: Matt Sedor, M.S., Yonathon Sciences, Inc.) Yoseph, P.G., C.H.G. (Remediation Jeff Baker (Vironex, Inc. ) Robert C. Borden and Christie Zawtocki, Michael D. Lee, Erica S Becvar, Patrick E. Haas, Bruce M. Henry, AFCEE Protocol For Enhanced Anaerobic Bioremediation Using Edible Oils

41 lide 41 For More Information Contact John Sankey, P.Eng or (604) Visit Design Tool, Case Studies Complete Product Line Chlorinated Solvent Site Remediation EOS, emulsified soybean oil, for enhanced in situ bioremediation BAC 9, microbes for bioaugmentation Petroleum Site eanup Remediation EOx, a calcium-based oxygen releasing substrate for aerobic bioremediation