Self-Sustaining Treatment for Active Remediation (STAR): Overview and Applications of the Technology

Transcription

1 Self-Sustaining Treatment for Active Remediation (STAR): Overview and Applications of the Technology Shanna Thompson, P.E. Gavin Grant, Ph.D., P.Eng. In Partnership with: siremlab.com/star

2 Overview The STAR process: combustion and smoldering Ex Situ STAR Early days of experimentation Reactor development In Situ STAR Case Study: STAR Pilot Test at a Former Industrial Facility in New Jersey 2

3 What is STAR? STAR: Self-sustaining Treatment for Active Remediation Patented technology based on principles of smoldering combustion Addresses recalcitrant contaminants Coal tar, creosote, petroleum hydrocarbons, solvents, etc. Reduced costs versus other technologies Extensive laboratory research and pilot testing 3

4 The STAR Advantage Safer In situ (no handling / transportation) Stationary / small / standard equipment Reduced cost versus other technologies Rapid Source area treatment in weeks to months Complete source remediation Sustainable technology 4

5 Combustion and Smoldering Combustion is: Exothermic reaction converting carbon compounds to CO 2 + H 2 O Fuel Contaminated Soil or Waste Product Heating Element (for ignition only) Combustion Injected Air Heat Oxidant Large surface area brought about by presence of porous matrix (e.g., aquifer) allows smoldering 5

6 Combustion and Smoldering Video accelerated 50 times 6

7 Combustion and Smoldering Treatability study soils (before and after) for the New Jersey Case Study before after 7

8 STAR Application Ex Situ STAR STAR applied above ground in reactors Highly effective and controlled application Ideal for: Excavated contaminated soils and sediments Waste oils/tank bottoms Lagoon sludges In Situ STAR STAR applied below ground via wells and portable in-well heaters Above or below water table Range of contaminated soils treated in place 8

9 STAR Application Ex Situ 9

10 STAR Application Ex Situ 10

11 STAR Application In Situ 11

12 siremlab.com/star Ex Situ STAR: Smoldering Combustion Reactors

13 Ex Situ STAR Pilot Test Reactor Robust testing program underway: Oily waste (tank bottoms) Hydrocarbon contaminated soils Drilling muds 13 13

14 Ex Situ STAR Pilot Test Reactor Example: Crude Oil Tank Bottoms Before TPH avg = 137,000 mg/kg After TPH = ND 14

15 Ex Situ STAR - Summary Well suited treatment option for waste oils and lagoon sludges Self-sustaining process (low energy) to completely destroy organic waste materials Robust system Full-scale commercial units became available in 2014: Reactors Soil piles 15

16 siremlab.com/star In Situ STAR: Case Study: STAR Pilot Test at a Former Industrial Facility in New Jersey

17 Case Study - Site Overview 37 acre cresol manufacturing facility in Newark, New Jersey PSE&G STAR compared to excavation and disposal: 55,000 CY treatment volume for STAR 300,000 CY to be removed in excavation Coal tar primarily in former waste lagoons (now infilled) Diamond Alkali Ashland Chemical Co Passaic River Site 17

18 Case Study Site Geology 18

19 Case Study - Coal Tar Distribution Above Meadow Mat Below Meadow Mat 19

20 In Situ STAR Case Study Objectives Pilot test designed to evaluate STAR: At a large scale Under saturated conditions (i.e., below ground surface and below the water table) Quantify mass destruction rates and remediation efficiency 20

21 In Situ STAR Case Study Phase I and II Shallow fill unit (10 ft) 20 ft x 60 ft pilot test area WT at 2 ft bgs Sheet pile installed to underlying peaty clay layer Phase III Deep sand unit 25 ft below water table No sheet pile 21

22 Phase I and II Shallow Fill Unit Coal Tar Mass Destroyed Coal Tar Destruction Rate Cumulative Coal Tar Mass Destroyed (kg) CoalTar Mass Destroyed During Phase I and Previous Phase II Activities Vapors kg of TVOCs emitted for every kg coal tar 20 destroyed in situ Coal Tar Mass Destruction Rate (kg/hr) Time from Igntion at IP-5 (Days) 0 22

23 Phase I and II Shallow Fill Unit Post-pilot Soil Sampling Before After 23

24 Phase I and II Shallow Fill Unit Post-pilot Characterization 4.5 tons of coal tar destroyed Sustained destruction rates > 800 kg/day at a single well Combustion front propagation up to 30 feet Concentration reductions of 2-3 orders of magnitude Comparison Before After TPH Concentration* 38,386 mg/kg 258 mg/kg Reduction 99.3% *average concentrations from 15 before samples and 8 after samples 24

25 Phase III Deep Sand Unit Pre-pilot Characterization No physical barrier to groundwater flow around pilot test area Impacts to 25 ft below water table 25

26 250 Phase III Deep Sand Unit Cumulative peak temperature in deep sand (all depths) Ignition point (IP-5) at center of plot IP-5 Day No sheet pile Notes: Scale in feet = thermocouple locations

27 Phase III Deep Sand Unit Post-pilot Characterization Compound Concentration Reduction (% ) in soil* Total Aromatics 98.6 Total Aliphatics 99.7 Total BTEX / VOCs *percent reduction of average concentrations from 8 before samples and 13 after samples ROI = 10 to 12 feet (6 days) 2ft/d propagation rate 6 foot thickness of coal tar destroyed ( 800 kg) Average EPH reduction (mg/kg): Before = 18,463 (n=8) After = 162 (n=13) 27

28 Full-scale Application - Well Layout 100 grids Node locations are selected to minimize total mobilizations 1700 shallow wells 5 ROI 10 separation 300 deep wells 10 ROI 20 separation Many locations require two screen depths 2150 total screens 28

29 Full-scale Application Operational Plan 29 Within each node, ignition wells are divided into CELLS Cell size based on total available utilities 3 cells active per treatment plant: One just completed treatment and being extracted One in active treatment One being installed for next active treatment

30 Carbon Footprint

31 Summary STAR is robust and works both above and below the water table under fully saturated conditions Well suited for coal tar, creosote, petroleum hydrocarbons, and solvents Can be applied in situ or ex situ (reactors or soil piles) STAR is rapid, sustainable, and cost-effective Technology backed by a decade of world-class research 31