Presenter: Raymond Lees
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Bioremediation Studies for Nitrobenzene, Aniline, and Diphenylamine at a Former Explosives Manufacturing Facility Presenter: Raymond Lees Lingke Zeng Langan Engineering & Environmental Services, Inc. May 24, 2017 Session E5
Transcript of Presenter: Raymond Lees
Bioremediation Studies for Nitrobenzene, Aniline, and Diphenylamine at a Former Explosives
Manufacturing Facility
Presenter:
Raymond Lees
Lingke ZengLangan Engineering & Environmental Services, Inc.
May 24, 2017
Session E5
AcknowledgementCo-authors:• The Chemours Company, LLC
Sathya Yalvigi
• Viasant LLMark Lewis
• Langan Engineering & Environmental Services, Inc.
Kevin McKeeverStewart Abrams Ali CiblakAngelo falabell
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Outline• Background
• Objectives
• Bench Procedures and Results– Sampling
– Bulking
– Chemical Oxidation
– GAC
– Landtreatment Simulation
• Pilot Study
• Conclusions
3
Site Background• Facility in southern
New Jersey
• 37,000 cubic yards for treatment via landfarming
• Three years treatment cycle
Standard IGW
Unit mg/kg
Aniline 35
Diphenylamine 630
Nitrobenzene 4
4
Contaminants of Concern
• Nitrobenzene (NB): aerobic and anaerobic degradation
• Aniline: aerobic
• Diphenylamine (DPA): aerobic
Nitrobenzene Aniline DPA Napthalene TCE
Density, g/mL 1.2 1.02 1.2 1.145 1.46
Solubility in water, g/L
1.9 36 0.3 0.0316 1.28
Vapor pressure, mmHg
0.15 (@20 C)0.6
(@20C)1 (@108 C)
0.065 (@20C)
58 (@20 C)
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DPA
NBAniline
Remedial Obstacles
• NB showed strong toxicity at levels above 140 mg/kg1 << Average NB concentration
• Low permeability clay/silt
• Fixed time frame– One year for landfarming
– 53 days per lift
O2
N&PH2O
1: Treatability study was completed by Professor Jim Spain of Georgia Tech
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Objectives
• Identify the reagent (bulking) to break cohesive soil
• Reduce contaminant toxicity
– Chemical oxidation
– GAC adsorption
– Bioaugmentation
• Determine kinetics via simulating landfarmingtreatment
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Procedure and Results-SamplingSoil Sampling and Baseline Characterization:• Soil collected from 7 test
pits for 6 AOCs• Concentrations – DPA up
to 10,000 mg/kg, NB up to 3,000 mg/kg, and aniline up to 6,500 mg/kg
• Clay content – up to 80% highly plastic clay
• Moisture content – soil 20% to 30% by weight, but wetland soil up to 50% by weight
Wetland Soil
Clayey Soil
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• Bulking – break up cohesive soil to increase permeability
• Seven Reagents: gypsum(s), lime, vermiculite, perlite(s), sawdust, mulch, corn cobb were tested in various combinations
Procedure and Results-Pretreatment Bulking
Mixing Air Permeability Test NB soil mixed with various ratios of vermiculate
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• Combination of Damp gypsum (DG) and vermiculite (V)
Procedure and Results-Bulking
Control
1.5% Gypsum
1.5% Gypsum and 1%
Vermiculite
1.5% Gypsum and 2%
Vermiculite
0.00E+00
1.00E-08
2.00E-08
3.00E-08
4.00E-08
5.00E-08
6.00E-08
7.00E-08
8.00E-08
9.00E-08
Pe
rme
abili
ty c
m2
Soil Source Area
Clay Content
Bulking Agents
Instant Volume
Change, %
NB Source 33%2% DG and
1% V 12.5%
NB Ditch 50%3% DG and
2.5% V44.3%
DPA Source 83%3% DG and
6% V54.2%
• 10% clay needs 1% (w/w) vermiculite
• 1% vermiculite increases soil volume by 10% to 15%
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Chemical Oxidation
• Spiked soil to 8,000 mg/kg of NB
• Alkaline and iron activated persulfate, and Fenton– No reduction with
persulfate
– 35% reduction with Fenton
– High SOD of 35 g/kg0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
Day3 Day 7
Nit
rob
en
zen
e,
mg
/kg Control
AlkalinePersulfate
IronPersulfate
Fenton
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GAC Adsorption• Purposely reduced
aqueous concentrations to stimulate microbial growth
• Elevated TOC resulted in effective dosage of 14 g/kg
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Landfarming Simulation • 72 reactors
– Bulking – combination of DG and vermiculite
– Toxicity Control - GAC 4 and 14 g/kg and bioaugmentation culture ENV 625, produced by CB&I’s biotechnology group
• 10 inch soil columns
• 3 to 4 times/week of mixing and moisture addition
• Up to 35 days of treatment
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NB and Aniline Soil Results
• Abiotic reduction contributed to the NB and aniline reduction.
• Elevated aniline also showed toxicity.
• Bioaugmentation did not significantly enhance NB reduction.
0
200
400
600
800
1,000
1,200
1,400
Nit
rob
en
zen
e, m
g/k
gDay 0 Day 20 or Day 12 Day 35 or Day 26
98.3% 99.7%
17.2%7.4%
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
An
ilin
e, m
g/k
g
NB Concentration
Aniline Concentration
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target level = 35 mg/kg Aniline IGW
77.8%
24.2%
target level = 4 mg/kg NB IGW
78.1% -32% 95.9% 95.5%
68.8% 66.1%
NB and Aniline Soil Results
• Bioaugmentation did not appear to significantly enhance NB reduction.
• More 108 CFU/g -rapid degradation
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
HP
C, C
FU/g
Plate Count
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Spiked Soil-NB 5,000 mg/kg
• Elevated NB showed toxicity.
• GAC reduced toxicity and increased microbe population but also prevented contaminant loss via abiotic path.
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
Nit
rob
en
zen
e, m
g/k
gDay 0 Day 12 Day 26
NB Concentration
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
HP
C, C
FU/g
Plate Count
Spiked Soil
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target level = 4 mg/kg NB IGW
42% 60% 67% -50%
36%
-32%
DPA Soil
• Only biotic reduction contributed to DPA reduction.
• Elevated DPA was not toxic.
• GAC & Bioaugmentation enhanced DPA reduction.
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0
2,000
4,000
6,000
8,000
10,000
12,000
DPA
, mg
/kg
Day 0 Day 20 or Day 12 Day 35 or Day 26
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
HP
C, C
FU/g
DPA Source
DPA Concentration
Plate Count
target level = 630mg/kg DPA IGW
-28% 92% 82% 79% 83%
63%
Pilot Study• Eight soil piles of 1.5 feet
high4 NB soil piles
4 DPA soil piles
• 50 cubic yards per soil pile
• 125 days of treatment
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Pilot Test Results
• Similar reduction rates• Detrimental affect from moisture saturation
0%
5%
10%
15%
20%
25%
30%
35%
40%
0
500
1,000
1,500
2,000
2,500
3,000
3,500
4,000
4,500
3 7 28 52 74 125 3 7 38 52 74 111 3 7 28 52 74 125 3 7 28 52 74 125
Mo
situ
re C
on
ten
t
Co
nta
min
ant
Co
nce
ntr
atio
n (
mg
/kg)
Treatment Duration (days)
Aniline
DPA
NB
MositureContent
NB-1 NB-2 NB-3 NB-4
99% 99% 99.9%
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99%
Results
• Similar reduction
0%
5%
10%
15%
20%
25%
0
1,000
2,000
3,000
4,000
5,000
6,000
0 5 28 50 120 0 5 33 50 120 0 5 28 50 120 0 5 28 50 120
Mo
situ
re C
on
ten
t
Co
nta
min
ant
Co
nce
ntr
atio
n (
mg
/kg)
Treatment Duration (days)
Aniline
DPA
NB
MositureContent
DPA-1 DPA-2 DPA-3 DPA-496%
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93% 90% 89%
Results0
1
10
100
1,000
10,000
100,000
NB-1 NB-2 DPA-1 DPA-4Co
nta
min
ant
Co
nce
ntr
atio
n
(mg
/kg)
Soil Pile
Ammonia
Nitrate
Sulfate
Sulfide
1.E+00
1.E+01
1.E+02
1.E+03
1.E+04
1.E+05
1.E+06
1.E+07
1.E+08
1.E+09
1.E+10
1.E+11
1.E+12
1.E+13
NB-1 NB-2 DPA-1 DPA-4
Mic
rob
ial A
cco
un
t (c
ell/
g)
Soil Pile
SulfateReducersAerobicBacteria
• Nitrate accumulated while ammonia did not accumulate.
• Aerobic microbe >> sulfate reducers
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Conclusions
• Kinetics: Bench and pilot study obtained highly consistent results.
• Toxicity– DPA no toxicity
– NB and aniline > 3,000 mg/kg
Height of Soil Pile
Half life
NB DPA
10 inch 5 to 6 days 15 to 21 days
18 inch 7 to 8 days 18 to 22 days
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Conclusions
• Reagent Recommendation
– Vermiculite (1%:10%), straw, and phosphate
– No GAC and oxidants
• Operation Parameters
– Optimal moisture content range between 10% and 15%
– Water addition may not be required
– Soil Pile Height < 18 inch.
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Conclusion• Kinetics
– Degradation of NB stalled at concentrations starting 20 mg/kg
– Degradation of DPA stalled at concentrations starting at 300 mg/kg
– Unable to reach the most stringent goal of 4 mg/kg for NB within 53 days (per treatment lift)
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