Remediation Design: Use of Bench Scale Testing. Kevin French Vertex Environmental Inc. SMART Remediation Vancouver, ON March 2, 2017

Transcription

1 Remediation Design: Use of Bench Scale Testing Kevin French Vertex Environmental Inc. SMART Remediation Vancouver, ON March 2, 2017 SMART is Powered by:

2 Vertex Environmental Inc. Remedial Design Use of Bench-Scale Testing SMART Remediation Vancouver March 2, 2017 Kevin French Outline What is Bench-Scale Testing? Why is it Important? Types of Bench-Scale Tests Examples of Bench-Scale Tests Closing Thoughts Questions 1

3 Vertex Environmental Inc. Company Vertex Environmental Inc. In-Situ Remediation 2

4 Bench-Scale Testing Vertex has an in-house laboratory Complete routine & custom-designed testing Participate in research & development of new technologies and amendment solutions 3

5 What is Bench-Scale Testing? Laboratory scale testing conducted on actual samples of contaminated soil, groundwater or free-product samples from a site Proof-of-concept testing to assess the feasibility and effectiveness of treatment using new amendments or on unusual or unique combinations of contaminants Small scale, multi-variable, low cost testing used to refine full-scale treatment approaches Why is it important? Assists in identifying the optimal type and concentration of remediation amendment required Quantifies the duration required for the remedial amendment to be in contact with the contaminated media to achieve objectives Observations or measurements can be made regarding potential remedial by-products or residuals Lowers uncertainty and makes full-scale designs more certain, accurate and cost-effective 4

6 Types of Bench-Scale Tests Microcosm or static batch reactors Flow-through column reactors Types of Bench-Scale Tests Microcosm or Static Batch Reactor Tests: Small quantities of soil or groundwater from a site or spiked samples to simulate site conditions Physical, chemical, biological or combinations of testing possible Aerobic or anaerobic conditions Testing of organic or inorganic contaminants Relatively quick, easy and inexpensive to complete 5

7 Types of Bench-Scale Tests Flow-Through Column Reactor Testing: Larger quantities of groundwater from a site or spiked samples Physical, chemical, biological or combinations of testing possible Aerobic or anaerobic conditions Testing of organic or inorganic contaminants Slightly more complicated and expensive to complete Examples of Bench-Scale Tests 6

8 Peroxide and Formaldehyde Static Batch Reactor Objective: Evaluate the effectiveness of hydrogen peroxide in treating formaldehyde in groundwater Site Background Truck carrying 35,000 L of heated waste formaldehyde spill Cascaded down embankment, along a secondary road, through a culvert Residents from 30 properties were evacuated Drinking water ban Truck Overturned 7

9 Fifteen short seconds changed our lives, local resident 8

10 Bench-Scale Methodology Groundwater from Site wells Bench-Scale Testing Control (groundwater sample, worst case ) 2.3% Unactivated Hydrogen Peroxide 2.3% Activated Hydrogen Peroxide 6.4% Activated Hydrogen Peroxide Sampling Times - Day 0 (Dose GW Samples) - Day 1 - Day 5 Bench-Scale Methodology 9

11 10,000,000 Formaldehyde Concentration (ug/l) 1,000, ,000 10,000 1, Control - no oxidant Test A - 2.3% oxidant, no activator Test B - 2.3% oxidant, activator Test C - 6.4% oxidant, activator Time (days) The North Bay Nugget November 12,

12 Phosphates and Lead Static Batch Reactor Objective: Evaluate the effectiveness of phosphates and other amendments in stabilizing leachable lead in soil Site Background Former DND site had soils impacted with lead (leachate toxic) from bullets and bullet fragments as a result of the historic usage of the Site as a firing range (WWI and WWII) 11

13 Bench-Scale Methodology Large metal fragments (bullets) were screened from soil Batch reactors were created by mixing varying concentrations of amendments with the soil Tested lime (provided testing), phosphates, ph, Cl Following a 3 day incubation period, soil samples were submitted for laboratory analysis of the target compounds Results were compared to Ont. 347 Reg. TCLP concentrations to determine if the leachate toxic soil was rendered non-hazardous by the treatments Bench-Scale Methodology Amendment Samples 12

14 Bench-Scale Testing 1000 Results: Lead Stabilization vs Concentration of Amendment 100 TCLP Lead (mg/l) 10 Regulatory Limit 5 mg/l Amendment Concentration (%) 13

15 Results and Conclusions Feasibility for pilot-scale confirmed Pilot-scale testing completed (9 cells, including control) Assessed range of amendments (lime and phosphate) and different mixing methods Vertex staff underwent UXO training as a precaution only Results and Conclusions First bucket of soil from first test pit revealed an old RPG Evacuated site and called posted emergency number Police bomb squad called in to detonate 14

16 Results and Conclusions Proceeded with extreme caution thereafter More UXO encountered and detonated Pilot-scale confirmed bench results (1% phosphate effective) Wastewater Treatability Flow-Through Column Reactor Objective: Evaluate the effectiveness of various filtration media in treating a complex waste water stream for a fullscale WTS design 15

17 Site Background Fire-testing laboratory generating waste water that needs to be treated. Wastewater generated could contain any or all of the following parameters: VOCs, SVOCs, PAHs, PHCs Oil and grease (O&G) Metals, Cyanide, Fluoride BOD, COD, TSS Dioxins and Furans Formaldehyde Perfluorinated compounds (PFCs) Nitrogen and sulphur compounds Phenols Bench-Scale Methodology Series of sequential flow through columns: Physical pre-filtration Column 1 - Organoclay Column 2 - Bituminous coal carbon Column 3 - Coconut carbon Column 4 - Bone char Column 5 - Activated alumina 16

18 Results and Conclusions Evaluation of removal efficiencies of COCs by media completed All COCs lowered to below discharge limits including PFCs Recommendations for full-scale WTS developed and costed Proactive decision made to add a final activated carbon filter just prior to effluent discharge 33 Complexation of Metals Flow-Through Column Reactor Objective: Evaluate the feasibility of removing metals in a fast moving groundwater regime 17

19 Site Background Metal ore mining site adjacent to freshwater stream Steep topography and coarse soils Very high groundwater flow velocity of 1 m/d! Low ph and high concentrations of Zn, As and Cd Passive treatment PRB preferred approach Bench-Scale Methodology Obtained samples of groundwater and benthic sediments from site Set up static batch reactors with different media Assessed performance Set up multiple flow-through column reactors with preferred media Recorded flow rates (contact times) and analyzed effluent Interactively adjusted media composition to provide better treatment 18

20 Bench-Scale Testing Bench-Scale Testing 19

21 Bench-Scale Testing Bench-Scale Observations 40 20

22 Bench-Scale Observations 41 Bench-Scale Observations 42 21

23 Bench-Scale Observations 43 Bench-Scale Observations 44 22

24 Bench-Scale Observations 45 Bench-Scale Observations 46 23

25 Results and Conclusions Simple and inexpensive static batch reactors used to screen a wide variety of possible amendments Short list of promising amendments carried through to flow-through column reactors Further narrowing down on suitable amendments (based on treatment effectiveness and permeability) Further refinement of remedial amendments to improve treatment efficiency to meet standards within contact time restrictions (1 day) Standards achieved! Long-term, flow-through column testing underway to demonstrate consistent performance over time 47 Other Interesting Examples 24

26 Bench Scale Testing Bench Scale Testing 25

27 Soil Consolidation vs. Time 100.0% 98.0% 96.0% 94.0% Soil Consolidation (%) 92.0% 90.0% 88.0% Control Samples 1-C 2-C 3-C 4-O 5-O 6-O 86.0% 84.0% 82.0% Oxidant Samples 80.0% Time (hours) Clean Sand Product 350 ppm 1,100 ppm 10,000 ppm 84,000 ppm 26

28 Bench Scale Testing Closing Thoughts Quick and easy to test multiple approaches for low cost Uses actual soil and groundwater from the site to better predict remedial outcomes (avoid costly mistakes!) Reduces uncertainties based on standard assumptions or rules-of-thumb Confirm ability to treat of new, unique or complex mixtures ( proof-of-concept ) Estimate treatment timeframes Predict ability to meet treatment objectives Assist in full-scale / detailed remedial design and costing A few hundred dollars at bench-scale can save thousands to tens of thousands of dollars in the field! 27

29 Questions? Thank You for Your Time Kevin French Vertex Environmental Inc. (519) mobile 28