A Water Chemistry Perspective on Flowback Reuse with Several ...
Water Quality Treatment - Produced Water & Flowback
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Transcript of Water Quality Treatment - Produced Water & Flowback
Water Quality and Treatment of Frac Flowback and Produced Water
Nasim EsmaeiliradRyan Hutcherson
Colorado State University
August 12, 2013
Overview on produced water
• Oil and gas within underground in source rock referred as Formations.
• Geology of formations vary along with hydrocarbons characteristics.
• Different methods are used for different formations.
• While some oil and gas are produced by drilling a well and relying on the natural pressure to come out to the surface, hydraulic fracking is used to extract some hydrocarbons .
• Hydraulic fracking: Injection of water along with chemicals and sand under high pressure inside the ground.
• Produced water is a key byproduct comes out to the surface along with oil and gas.
• 250mbbr of produced water was generated per day in the world in 2009, corresponding to 80mbbrs of produced oil.
• 21mbbrs of PW was generated in the USA.
• About 90% of produced water is injected to the deep wells.
• Given this huge amount of produced water and growing demand of fresh water give a potential source of water in replace of conventional source of water
Basic Water Use Model
Groundwater
Municipal Water
Surface Water
Drilling and Hydraulic Fracturing
Flowback and Produced Water
Deep Injection Well
Water Reuse Model
Groundwater
Municipal Water
Surface Water
Drilling and Hydraulic Fracturing
Flowback and Produced Water
Deep Injection Well
Treatment
Dilution
Sampling Plan
Flow back Transition Formation
- Unsuccessful Treatment
- Treatment to be completed- Successful Treatment
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 1850
200
400
600
800
1000
1200
1400
1600
Days
BBLS
0 20 40 60 80 1000
50
100
150
200
250Frac Fluid ll Frac Fluid ll
Days
Iron
(mg/
L)
0 2 4 6 8 10 120
20
40
60
80
0 20 40 60 80 1000
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
Frac Fluid ll Frac Fluid ll
Days
Alum
inum
(mg/
L)
0 2 4 6 8 10 12012345
Raw Water Quality
Raw Water Quality
0 20 40 60 80 1000
50
100
150
200
250
300
350
400
Frac Fluid l Frac Fluids ll
Calci
um (m
g/L)
0 2 4 6 8 10 120
50
100
150
200
0 20 40 60 80 1000
5
10
15
20
25
30
35
Frac Fluid l Frac Fluid ll
Days
Bariu
m (m
g/L)
0 2 4 6 8 10 12012345
Raw Water Quality
0 20 40 60 80 1000
2000
4000
6000
8000
10000
12000
14000
16000
18000Frac Fluid l Frac Fluid ll
Days
Chlo
ride
(mg/
L)
0 2 4 6 8 10 120
2000400060008000
10000
0 20 40 60 80 1000
200
400
600
800
1000
1200
1400
Frac Fluid l Frac Fluid ll
Days
Sulfa
te (m
g/L)
0 2 4 6 8 10 120
500
1000
1500
Raw Water Quality
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 1051000
1500
2000
2500
3000
3500
4000
Frac Fluid l Frac Fluid ll
TOC
(mg/
L)
0 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 1050
5000
10000
15000
20000
25000
30000
Frac Fluid l Frac Fluid ll
Days
TDS
(mg/
L)
0 0.5 1 1.5 2 2.5 3 3.5 4400900
140019002400290034003900
Raw Water Quality
0 20 40 60 80 1000
1
2
3
4
5
6
7
8
9
Frac Fluid ll Frac Fluid l
pH
(1) Electrocoagulation => Softening => Solid-Liquid Separation
(2) Softening => Electrocoagulation => Solid-Liquid Separation
(3) Chemical coagulation => Softening => Solid-Liquid separation
Chemical and Electro Coagulation (EC) Processes Studied
Goals:
• Determine the point in time when flowback can be treated effectively
• Determine what type of treatment and dosage is most effective on early flowback
• Determine which water quality parameters could be used as indicators of whether treatment will be successful
Chemical Coagulation
• Destabilize (charge neutralize) solid particles using tri-valent cations• A blend of Aluminum and a polymer were used• HCl was used to lower the raw water pH to 6 (increase hydration of floc blend)• Each raw sample was treated with a dosage of 5 parts per thousand of Floc
Blend and stirred for approximately 2 minutes• Floc Blend consists of a 1:1 ratio of Aluminum Chlorohydrate (ACH) and Poly-
aluminum Chloride (PACl) • Aluminum dosage was approximately 449 mg/L• Floc was allowed to settle for approximately 20 minutes• Once settled water was decanted off the top softened at a pH of 10.2 (NaOH)
2.5μm glass fiber filters either with positive pressure or a vacuum were used• HCl was then used to lower pH to neutral (~ 7)
Electrocoagulation
Insitu generating coagulants:
• Using electricity to dissolution and oxidation of
metal ions in anode: Aluminum or/and Iron plates/disc.
• Formation of hydroxyl ions(Aluminum hydroxide) and hydrogen gas at the cathode.
• Reacting with the hydroxyl ion (from the cathode) to
form Aluminum hydroxide.
• The hydroxide flocculates and coagulates purifying
the water.
EC/Softening (1) and Softening/EC (3) Schematics
Raw water
EC pH = 10.2(NaOH)
pH = 7(HCl)(1)
(2)
2.5 mm filter
Sample A
2.5 mm filter
Sample B
2.5 mm filter
DissolvedTotal
2.5 mm filter
2.5 mm filter
pH = 7(HCl)
pH = 9.5(NaOH)
Sample A Sample B Sample C
EC
EC (1) and Chemical Coagulation (2) Schematics
Raw water
EC pH = 10.2(NaOH)
pH = 7(HCl)(1)
(3)
2.5 mm filter
Sample A
2.5 mm filter
Sample B
Sample A Sample B Sample C
2.5 mm filter
DissolvedTotal
ChemicalTreatment
pH = 10.2(NaOH)
2.5 mm filter
2.5 mm filter
pH = 7(HCl)
Treated Water Quality (EC vs. CC)
1 2 26.5 69.5 90 153 161 183 1 2 700
50
100
150
200
250
300
350
400
450
500
50
55
60
65
70
75
80
85
90
95
100RawPost-ECPost-CC% Removal-EC% Removal-CC
Alu
min
um (m
g/L)
%
Frac Fluid l (guar based, pH=10.2) Frac Fluid ll (non-guar, pH=5)
1 2 26.5 69.5 90 153 161 183 1 2 700
50
100
150
200
250
0102030405060708090100 Raw
Post-ECPost-CC% Removal-ECSeries5
Iron
(mg/
L)
%
Treated Water Quality (EC vs. CC)
1 2 26.5 69.5 90 153 161 183 1 2 700
50
100
150
200
250
300
350
400
450
0
10
20
30
40
50
60
70
80
90 RawPost-ECPost-CC% Removal-EC% Removal-CC
Calc
ium
(mg/
L)
%
1 2 26.5 69.5 90 153 161 183 1 2 700
5
10
15
20
25
30
35
0102030405060708090100 Raw
Post-ECPost-CC% Removal-EC% Removal-CC
Bari
um (m
g/L)
%
Frac Fluid l (guar based, pH=10.2) Frac Fluid ll (non-guar, pH=5)
Treated Water Quality (EC vs. CC)
1 2 26.5 69.5 90 153 161 183 1 2 700
500
1000
1500
2000
2500
0
20
40
60
80
100
120 RawPost-ECPost-CC% Removal-EC% Removal-CC
COD
(mg/
L)
%
1 2 26.5 69.5 90 153 161 183 1 2 700
500
1000
1500
2000
2500
0
20
40
60
80
100
120RawPost-ECPost-CC% Removal-EC% Removal-CC
TOC
(mg/
L)
%
Frac Fluid l (guar based, pH=10.2) Frac Fluid ll (non-guar, pH=5)
1 2 26.5 69.5 90 153 161 183 1 2 700
500
1000
1500
2000
2500
3000
3500
4000
4500
0
20
40
60
80
100
120 RawPost-ECPost-CC% Removal-EC% Removal-CC
Turb
idit
y (N
TU)
%
Treated Water Quality (EC vs. CC)
Frac Fluid l (guar based, pH=10.2) Frac Fluid ll (non-guar, pH=5)
Treated Water Quality (softening before/after EC)
1.00 1.00 2.00 2.00 30.00 60.00 60.00 90.00 153.00 161.00 183.000.00
500.00
1000.00
1500.00
2000.00
2500.00
3000.00
3500.00
4000.00
4500.00
-150.00
-100.00
-50.00
0.00
50.00
100.00
150.00
-61.71
-38.43 -46.15
87.62 95.06 99.68 99.76 99.82 98.85 99.72 98.56
Turbidity
Raw EC pH
EC removal pH removal
Days
Turb
idit
y(N
TU)
Rem
oval
%
1.00 1.00 2.00 2.00 30.00 60.00 60.00 90.00 153.00 161.00 183.000.00
500.00
1000.00
1500.00
2000.00
2500.00
3000.00
0.00
500.00
1000.00
1500.00
2000.00
2500.00
3000.00
3500.00
4000.00
4500.00TOC Vs Turbidity
TOC TOC-EC TOC-pH Turbidity Turbidity-EC
Turbidity-pH
Days
TOC(
mg/
l)
Turb
idit
y(N
TU)
Treated Water Quality (softening before/after EC)
1.00 1.00 2.00 2.00 30.00 60.00 60.00 90.00 153.00 161.00 183.000.00
50.00
100.00
150.00
200.00
250.00
300.00
350.00
400.00
450.00Hardness
Raw-Ca+2 EC-Ca+2 pH-Ca+2 Raw-Mg+2 EC-MG+2 pH-Mg+2
Days
Conc
entr
ation
(mg/
)
Treated Water Quality (softening before/after EC)
1.00 1.00 2.00 2.00 30.00 60.00 60.00 90.00 153.00 161.00 183.000.00
20.00
40.00
60.00
80.00
100.00
120.00
140.00
160.00
180.00
200.00
0.00
5.00
10.00
15.00
20.00
25.00
30.00
35.00
40.00
45.00
50.00Al vs Fe
Fe+2 EC-Fe+2 pH-Fe+2 Al+3 EC-Al+3pH-Al+3
Days
Fe+2
(mg/
l)
Al+
3(m
g/l)
Treated Water Quality (softening before/after EC)
Treatment Comparison after 1 hour
Treated Water Quality (softening before/after EC)
Comparison between EC Only and Increased pH before EC
Treated Water Quality (softening before/after EC)
Future Work
• Collect water samples for chemical treatability study• 5 days, 10 days, 20 days• Frac Fluid l and Frac Fluid ll• Use same chemical treatment process
• Repeat flowback study• Time intervals to be determined• Treat samples with various coagulants and processes (i.e. Alum, Ferric
Chloride, 2 stage treatment)• Measure change in dose-repose over the first month to better understand
treatability changes with time.• Additional Analytical Parameters
• Detailed characterization of organics• Seek a more simple measure of the class of organics which are found to be
most important (from a treatment point of view)