Nghiên cứu kết hợp phương pháp nội điện phân và phương pháp mảng sinh học lưu động a2o MBBR để xử lý nước thải nhiễm TNT tt tiếng anh

MINISTRY OF EDUCATION
VIETNAM ACADEMY OF
AND TRAINING
SCIENCE AND TECHNOLOGY
GRADUATE UNIVERSITY OF SCIENCE AND TECHNOLOGY

VU DUY NHAN

STUDY ON INTERNAL ELECTROLYSIS COMBINE WITH
AAO-MBBR TO TREAT TNT WASTEWATER

Speciality: Chemical Engineering
Code: 9 52 03 01

PhD DISSERTATION SUMMARY ON CHEMICAL
ENGINEERING

Ha Noi - 2020


The work was completed at:
Vietnam Academy of Science and Technology

Science instructor:
1. Assoc. Prof. Le Thi Mai Huong
2. Prof. Le Mai Huong
Reviewer 1:

Reviewer 2:

Reviewer 3:

The dissertation will be presented in front of Dissertation Evaluation
Council at Institute level at the Institute of Natural Products
Chemistry - Vietnam Academy of Science and Technology, No. 18
Hoang Quoc Viet, Cau Giay, Hanoi.
At

,

/

/

The dissertation can be found at:
1, National Library of Viet Nam
2, Library of Institute of Natural Products Chemistry Vietnam Academy of Science and Technology


I.
INTRODUCTION
1.1. Background
2,4,6 trinitrotoluene (TNT) is a chemical widely used in defense
and economy. The explosive manufacturing industry discharges a
large amount of wastewater containing toxic chemicals such as TNT.
In fact, about 50 years after World War II, in places where gunpowder
factories were built, large amounts of TNT and their isomers were
found in soil and water environments [1, 2, 21]. This proves that TNT
is capable of long-term survival in nature or in other words, TNT is
difficult to biodegrade. In our country, besides the factories is
producing ammunition, explosives, and launchers in the defense

industry, there are still a large amount of wastewater containing TNT
which needs to be treated in warehouses for repairing and collecting
ammunition.
The commonly methods are used to treat wastewater containing
TNT including: physical method (adsorption by activated carbon,
electrolysis); chemical method (Fenton, UV - Fenton, internal
electrolysis), biological method (aerobic activated sludge, MBBR,
UASB, MBR, plants, enzymes, white rot fungi). These measures may
be used independent or combination with each other, depending on
the nature of the wastewater and the material facilities and economic
conditions of the manufacture establishment.
This dissertation focuses on establishing the process of
manufacturing bimetallic Fe / Cu internal electrolysis nanomaterial,
thereby studying some characteristics correlation between corrosive
line and TNT decomposition kinetics and time. Setting and
optimizing the internal electrolysis process by bimetal Fe / Cu
nanomaterials combined with biological method A2O-MBBR
(moving bed Biological reactor) to treat TNT wastewater at laboratory
scale and Pilot scale at the scene. At the same time, the first step
establishing the control automatic or semi-automatic operation
software with the conditions of the treatment process are determined.

1


1.2. Research objectives
Bimetal Fe / Cu internal electrolytic nanomaterials
Internal electrolysis method and biological method A2O - MBBR to
treat wastewater containing TNT
1.3. New contributions

1.3.1. Successfully fabricated bimetallic Fe / Cu electrolytic
internal materials with average size of 100 nm, potential (voltage) E0 =
0.777 V. In electrolyte solution pH=3 with TNT concentration of 100
mg/L, corrosive current is reaching 14.85*10-6 A/cm2 and corrosion
speed reach 8. 87*10-2 mm / year. Therefore has increased the reaction
rate, processing efficiency is higher, faster. Concurrently, It has been
determined corrosion current and its relationship with LnCt / C0 depend
on the duration of the TNT reduction process by the corrosion current
measurement method. There has not been any announcement using this
method. Some related publication determined the relationship between
TNT reduction speed and reduction speed of H+ to H2.
1.3.2. Establishing TNT treatment technology by combining the
internal electrolysis method using bimetal Fe/Cu nanomaterials with
biological method A2O-MBBR. Nowadays, no announcement has
been made which combined these two methods to treat wastewater.
The microorganisms in the A2O-MBBR system used to treat
wastewater containing TNT has been identified, among them two
strains can be new: Novosphingobium sp. (HK1-II, HK1-III) have
bootstrap value of 97.4-97.92% to Novosphingobium sediminicola sp.
and Trichosporon (HK2-II, TK2-II and HK2-III) have bootstrap value
of 97.7% to middelhonenii sp. These two species were published on
the international gene bank with the code GenBank: LC483151.1;
LC483155.1
and
the
corresponding
link
are:
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2

1.4. The layout of dissertation
The dissertation consists of 191 pages with 24 tables, 101
pictures, 139 references and 2 appendices. The layout of dissertation:
Introduction (3 pages), Chapter 1: Literature review (44 pages),
Chapter 2: Materials and methods (15 pages), Chapter 3: Results and
discussion (79 pages) ), Conclusion (2 pages), Published works (1
page), References (15 pages), Appendix (17 pages)
II.

CONTENTS
INTRODUCTION
The introduction refers to the scientific and practical significance of
the dissertation
CHAPTER 1: LITERATURE REVIEW
Overview of international and domestic studies on issues such as:
The studies on treatment methods wastewater containing TNT
The studies on the internal electrolysis method to treat wastewater
Studies on Fe / Cu bimetallic materials fabrication method for
wastewater treatment.
Studies on combines biological method of A2O-MBBR to wastewater
treatment
The studies on software controls the wastewater treatment system.
CHAPTER 2: MATERIALS AND METHODS
2.1. Materials
Pure TNT
Wastewater containing TNT is collected from national defense
production facilities 121
100 nm size iron powder.

2.2. Methods
 Analytical methods:
Analytical methods to determine the structure, size, composition
of Fe / Cu bimetal nano: SEM, ERD, EDX.
Methods of measuring corrosive lines: potential range -1.00V0.0V, scanning speed 10 mV/s, Electrodes compare Ag/AgCl

3


(saturation). The corrosion line and the corrosion potential were
measured using Autolab PG30 (Netherlands).
TNT analytical methods: HPLC, Von – Amper
Methods of determining Fe content
Proceed to determine Fe ion content according to EPA 7000B
method on Contraa 700 device
Method of determining COD, T-N, T-P, NH4 +: According to
TCVN or ISO.
 Experimental method
1. Fabrication of Nano Fe / Cu materials: by CuSO4 plating method
on powder Fe average size of 100 nm on magnetic stirrer.
2. Treatment of TNT wastewater: Prepare a 100 mg/L TNT solution
into a 500 ml erlenmeyer flask, change the conditions reaction as pH,
temperature, shaking speed, Fe/Cu content to each corresponding
research.
3. Experimental planning method: Follow the quadratic planning BoxBehnken and Design-Expert optimization software version 11.
4. Isolation of activated sludge: To activate, take activated sludge
from wastewater containing TNT treatment stations of production
facilities 121, 115. Then, activated sludge in anaerobic, anoxic and
oxic activated condition of 30 days. Then proceed to isolate
microorganism system in the sludge is activated.

5. Microbiological classification method: Conduct DNA sequencing
of selected strains, then compare with the DNA sequence of 16S are
published species by the DDBJ, EMBL, GenBank.
CHAPTER 3: RESULTS AND DISCUSSIONS
The chapter’s content includes: establishing conditions for
manufacturing bimetal Fe/Cu nanomaterials, the effects of internal
electrolytic factors, A2O-MBBR to treat wastewater containing TNT
and optimize treatment conditions, Kinetic characteristics of internal
electrolytic reaction, the diversity of microorganisms in the A2OMBBR system, the software control the internal electrolytic system
combined with A2O-MBBR to treat wastewater containing TNT.
4


3.1. Fabrication of internal electrolytic materials Nano bimetal
Fe/Cu
This section write details the results of the research to establish
the reaction conditions for creating Fe / Cu materials: Fe powder of
100 nm size is plated by CuSO4 solution at a concentration of 6% in 2
minutes. Fe/Cu materials have Cu concentration on the surface of
68.44% and copper atomic mass reaches 79.58%.

b
a
Figure 3.1: SEM image (a) and EDS spectrum of Fe / Cu bimetallic
nanomaterials
Survey results and comparison of corrosion lines between 2 types of
bimetal nanomaterials Fe/C and Fe/Cu are shown in Figure 3.2:

a
b

Figure 3.2: Tafel line of galvanic corrosion of Fe/C electrode
system (a) and Fe/Cu after plating (b) at different time values
From Figure 3.2, it can be seen that the corrosion potential (EĂM) of
Fe materials has the descending rule towards the negative side.
However, the potential of Fe/Cu electrolytic internal materials reaches
- 0.563 V÷-0.765 V with absolute value higher than the corrosion
potential of Fe/C, only from - 0.263 V÷- 0.6693V.
5


Figure 3.3 shows that the corrosion speed of Fe / Cu material is
8,187.10-2 mm/year, which is nearly 2 times higher than that of Fe / C
material, only 4,811.10-2 mm/year.
1.6E-5

Dong an mon ir (A)

1.4E-5

Fe/Cu
Fe/C

1.2E-5

1.0E-5

8.0E-6

6.0E-6

4.0E-6
20

40

60

80

100

120

Thời gian (phút)

Figure 3.3: The dependent on time of corrosion line of electrode
material system: Fe/C before plating -- (a) and Fe/Cu after chemical
plating -■- (b)
Thus, bimetallic Fe/Cu electrolytic internal material has been
synthesized with average size of 100 nm, potential voltage E0 =
0.777 V. In electrolyte solution which have pH=3, concentration of
TNT 100 mg/L, Fe/Cu materials have corrosion current density
14.85*10-6 A/cm2 and corrosion speed 8,187*10-2 mm/year.
3.2. Effect of factors on the efficiency of TNT treatment
3.2.1. Effect of pH
The effectiveness of TNT treatment depends on the initial pH value of
the electrolyte solution. The results are shown in the Figure 3.4:
100

100

80

60

TNT (mg/L)

TNT(mg/L)

60

40

20

40

20

0
2

2
2.5
3
3.5
4
4.5
5
5.5

6

80

0

3

4

5

0

6

pH

20

40

60

80

100

120

140

160

180

Thời gian (phút)

Figure 3.4: Treatment efficiency of
Figure 3.5: Dependence
TNT in different initial pH treatment efficiency on initial pH
conditions at the time of 90 minutes
over time
6


Figures 3.4 and 3.5 show that during the first 90 minutes, the reaction
speed was very fast, achieving high processing efficiency. At 90
minutes, the TNT concentration reached 1.61; 1.62; 1.71 and 1.72
mg/L and treatment efficiency in turn 98.29; 98.22; 98.34 and 98.22%
correspond to the initial pH values of 2.0; 2.5; 3.0; 3.5. For pH 4.0;
4,5; achieved a lower efficiency and the corresponding TNT
concentration was 3.05; 13.09 mg/L. Values pH 5.0; 5.5 and 6 have
the lowest treatment efficiency, with TNT concentrations respectively
are 26.03; 56.36 and 89.03 mg/L. From 90th to 180th minute, the
processing efficiency slows down and does not change significantly.
3.2.2. Effect of Fe/Cu material content
Conducting survey on the influence of different Fe/Cu material
content inTNT treatment efficiency. The experiments have been
conducted with 10; 20; 30; 40; 50; 60 g/L of Fe/Cu. The result is

shown in Figure 3.11; 3.12 and 3.13.
32

100
90

28

80

24
20

60

TNT(mg/L)

TNT(mg/L)

10 g/L
20 g/L
30 g/L
40 g/L
50 g/L
60 g/L

70

16
12

50
40
30
20

8

10

4

0

0

-100

10

20

30

40

50

30

60

90

120

150

180

60

Thời gian (phút)

Hàm lượng Fe/Cu (g/L)

Figure 3.6: Dependence of TNT Figure 3.7: Change of TNT
treatment efficiency at 90th concentration over time at
minutes on the content of Fe / Cu different Fe / Cu content
The Figures 3.6 and 3.7 show that the content of materials has
effectted on the efficiency of TNT treatment. Thus, the effectiveness
of TNT treatment depends on the content of Fe/Cu electrolytic
internal materials into the reaction. With material content Fe/Cu is 30;
40; 50; 60 g/L, after 180 minutes of reaction, reached the highest
treatment efficiency of 99.99% and pH value increased to 5.5.
7


3.2.3. Effect of temperature
Temperature has an effect on the rate of internal electrolysis

reaction, the higher the temperature, the faster the reaction speed and
conversely.
6

100
5

20
25
30
35
40
45

80

TNT (mg/L)

TNT(mg/L)

4

3

2

60

8
4

40

0
80

20

120

160

1

0
020

25

30

35

40

45

0

Nhiệt độ (o C)

20

40

60

80

100

120

140

160

180

Thời gian (phút)

Figure 3.8: Dependence of Figure 3.9: The change in TNT
TNT treatment efficiency on concentration is treated by internal
temperature at first 90 minutes electrolyte material according to
reaction time at different temperatures.
Figures 3.8 and 3.9 show that the higher the temperature and the
faster the reaction speed and conversely. At the time of 90 minutes,
the temperatures at 40℃ and 45℃ treated TNT were most effective,
the concentration of TNT decreased to 0.57; 0.63 mg / L; next at 30℃,
35℃ is 1.76; 1.71 mg / L and finally at 20℃, 25℃ to 5.31; 3.60 mg /

L. Thus, it is clear that the higher the temperature and the faster the
reaction speed, the highest processing efficiency is at 45℃ and the
lowest is 20℃. The next phase, from 90 to 120 minutes, the reaction
speed slows down.
3.2.4. Effect of TNT concentration
The initial concentration of TNT affects the reaction speed and the
processing efficiency due to the following reasons: (1) contaminants
and intermediate decomposition products will compete with each
other on the surface of electrodes. (2) Different concentrations of
contaminants make the dispersion phase in contact between pollutants
with Fe / Cu electrode surface different:

8


110

1.7

40
60
80
100

100
90
80
70

TNT (mg/L)

TNT(mg/L)

1.6

1.5

40

60
50

20

40

0

30
30 40 50 60 70 80 90 100
20
10

1.4

0
-10
20

40

50

60

70

80

90

100

40

60

80

100

120

140

160

180

Thời gian (phút)

Nồng độ TNT ban đầu (mg/L)

Figure 3.10: Dependence of Figure 3.11: The change of TNT
TNT concentration remaining concentration after treatment
after treatment on the initial over time with different initial
concentration
TNT concentrations
Figure 3.10; 3.11 shows that the lower the concentration of TNT, the
higher the processing efficiency and conversely. After 90 minutes, the
remaining TNT concentration was 1.35; 1.42; 1.51; 1.68 mg/L
corresponds to the initial TNT concentrations of 40; 60; 80; 100 mg /
L. In the next phase, from 90 to 180 minutes, the effect of the initial
TNT concentration on the processing speed and efficiency is almost
no difference. At 180 minutes, the remaining TNT concentration was
corresponding to 0.15; 0.19; 0.21 and 0.23 mg/L.
3.2.5. Optimize the process of treating TNT wastewater
Applying Box-Behnken method for pH, temperature, shaking speed,
reaction time for regression equations:
Y = 93.16 + 1.05B + 3.02C + 8.62D - 0.265BC - 4.73CD + 1.12A2 1.11C2 - 3D2. Optimal conditions are determined from the regression
equation corresponding to: pH = 3.24, temperature at 32.6 ℃, shaking
speed of 91 rpm for 140 minutes and get TNT treatment efficiency of
98.29%. Among the factors that affect TNT's processing performance,
the time is greatest affect, follow is the temperature, but to a lesser,
the shaking speed and pH have little effect.

a

b
9

c

d

e
f
Figure 3.12: Relationship between factors on efficiency of TNT
treatment. (a): pH and time; (b) pH and temperature; (c) pH and
shaking speed; (d) temperature and time; (e) temperature and shaking
speed; (f) shaking speed and time.
3.3. Some kinetic characteristics of the internal electrolysis
process TNT
3.3.1. Iron corrosion rate and TNT decomposition kinetics
This section presents the results of the iron corrosion rate and the
correlation between the rate of TNT decomposition.
11
1.0

10
0.8
0.6

8
Ct/Co

Cion Fe(mg/L)

9

7
6

0.4
0.2

5
0.0

4
0

50

100

150

200

250

300

350

Thời gian (phút)

3

0

20

40

60

80

100

120

Thời gian (phút)

.
Figure 3.13: Dependence of Figure 3.14: Dependence of
dissolved Fe content on reaction TNT concentration on the
time of internal electrolysis process internal electrolytic reaction
time of Fe / Cu materials

10


Figure 3.13 and Figure 3.14 show the causal relationship between the
rate of iron corrosion and the iron concentration in TNT treatment
process depend on time.

Figure 3.15: Relationship between logarithms of concentration and time

Figure 3.15 proves that TNT is reduced by Fe / Cu internal
electrolysis reaction fit Level 1 Kinetic assumptions model. The
reaction rate constant is calculated by the slope (angular coefficient)
of the linear regression line.
3.3.2. Effect of pH and Fe/Cu content
0.0

0.5
0.0

-0.5

-0.5
-1.0

-1.5

pH=2 k=0.0371
pH=2.5 k=0.0369
pH=3 k=0.0367
pH=3.5 k=0.0366
pH=4 k=0.0307
pH=4.5 k=0.0224
pH=5 k=0.0084
pH=5.5 k=0.0059
pH=6 k=0.0011

-2.0
-2.5
-3.0

ln(Ct/Co)

ln(Ct/Co)

-1.0
-1.5

-2.0
10 g/L
20 g/L
30 g/L
40 g/L
50 g/L
60 g/L

-2.5
-3.0
-3.5

-3.5

k=0.0126
k=0.0205
k=0.0339
k=0.0452
k=0.0459
k=0.0459

-4.0

0

20

40

60

-4.5

80

0

Thời gian (phút)

20

40

60

80

Thời gian (phút)

Figure 3.16: Effect of initial pH Figure 3.17: Effect of Fe / Cu content
on the rate of TNT decomposition on the rate of TNT decomposition
3.3.3. Effect of shaking speed and temperature
0

0

-1

-1
-2

ln(Ct/Co)

ln (Ct/Co)

-2

-3

-4

20 oC
25 oC
30 oC
35 oC
40 oC
45 oC

-4
-5

60 rpm k=0.013
90 rpm k=0.025

120rpm k=0.044

-5

-3

-6

-6

k=0.0325
k=0.0382
k=0.0462
k=0.0543
k=0.0691
k=0.0746

-7
0

20

40

60

80

100

120

140

160

180

0

20

40

60

80

Thời gian (phút)

Thời gian (phút)

Figure 3.18: Effect of shaking speed Figure 3.19: Effect of temperature
on the rate of TNT decomposition
on the rate of TNT decomposition
11


Thus the activation energy Ea is calculated based on the graph of the
relationship between Ln k and 1 / T (Figure 3.20).

-2.6
Equation

y = a + b*x

Weight

No Weighting

Residual Sum
of Squares

-2.8

Adj. R-Square

0.98911
Value
Intercept

lnk

lnk

0.00467
-0.99563

Pearson's r

Slope

Standard Error

7.64344

0.49879

-3246.34703

152.20171

-3.0

-3.2

-3.4

0.00315

0.00320

0.00325

0.00330

0.00335

0.00340

1/T

Figure 3.20: Relationship between Lnk and 1/T: y = - 3246x +
7.6434 R2 = 0.9891
In Figure 3.20, it can be seen that the correlation coefficients of these
6 points on the regression line reach 0.9915, the Lnk and 1/T have a
strong linear relationship. The activation energy of the entire reaction
has been calculated: Ea = 3246 * 8.314 = 26.99 KJ/mol and indicates
that the TNT decomposition is in the diffusion domain, which in
accordance with the above research results.
3.3.4. Evaluate TNT molecular reduction process
Extreme spectrum Von - Amper for analyzing the position of NO2radicals. Thereby it is possible to assess the existence of 3 NO2radicals on the TNT molecule. In other words, it is possible to
evaluate the reduction of 3 NO2- radicals of TNT molecule into NH2
amine. The result is shown in Figure 3.21 as follows:
TNT
TNT

TNT
TNT

-160n

-140n

TNT3
TNT1 TNT2

-140n

-120n
-120n

I (A)

I (A)

TNT1
-100n

-100n

TNT2
TNT3

-80.0n
-80.0n

-60.0n
-60.0n

-40.0n
0.10

0

-0.10

-0.20

-0.30

-0.40

0.10

-0.50

0

-0.10

-0.20

U (V)

U (V)

a

b

12

-0.30

-0.40

-0.50


TNT

TNT

TNT
TNT

-100n

-200n
-80.0n

-175n

-60.0n

I (A)

I (A)

-150n

-125n

-40.0n

TNT1

TNT3

-100n
-20.0n

-75.0n

0.10

TNT1TNT2

0

-50.0n
0

-0.10

-0.20

-0.30

-0.40

0.10

-0.50

0

-0.10

-0.20

-0.30

-0.40

-0.50

U (V)

U (V)

c
d
Figure 3.21: Von - Amper spectrum of TNT decomposition process
at time 0 minutes (a); 15 minutes (b); 90 minutes (c); 330 minutes (d)
It can be seen that, at the 0 minutes, there were still 3 spectral peaks
equivalent to 3 NO2- radicals, after 15 minutes response the spectral
peaks was lower and to 90 minutes, there was only 1 spectral peak but
it was lower so many. At 330 minutes, the spectral peaks of the NO2radical are nearly flat. In other words, the NO2- on the TNT molecule
no longer exists.
3.3.5. Operating TNT wastewater treatment at laboratory with Fe
/ Cu material
This section presents the results of TNT wastewater treatment at
laboratory using electrolytic internal material for 30 days.
Table 3.1: TNT wastewater treatment efficiency
Initial
After treat
Eficiency (%)
COD (mg/L)
220 - 270
85 - 110

59, 2 - 61,3
TNT (mg/L)
95 –106,4
0
100
BOD5/COD
0,18 –0,2
0, 55 – 0,56
pH
5
6,5 – 6,6
3.3.5.1. Treatment efficiency of TNT
120

100

TNT(mg/l)

80
In

60

En

40

20

0

0

2

4

6

8

10

12

14

16

Times(day)

Figure 3.21: Treatment efficiency of TNT
13


a
b
Figure 3.24: HPLC spectrum of pre-treatment (a) and post-treatment (b)
3.3.5.2. COD removal efficiency
280

0.7

260

0.6

240
0.5

200

IN

180

EN

BOD5/COD

COD(mg/l)

220

160

0.4
0.3
0.2

140
0.1

120

0.0

100

3

4

5

6

7

pH

0

2

4

6

8

10

12

14

16

Time(day)

Figure 3.25: COD removal efficiency Figure 3.26: The change of BOD5
/ COD ratio after treatment.
3.4. Techniques A2O-MMBR treating TNT
3.4.1. Research isolated activated sludge
3.4.1.1. Isolation
Table 3.2: Characteristic of domesticated activated sludge
Mixed Liquor
Condition Suspended Solids
Characteristics
MLSS (mg/L)
yellowish brown, mud suspended,
Aerobic
2120 ± 50
the suspension
Dark brown, big mud cotton, rapid
Anoxic
1596 ± 50
sedimentation
black, heavy mud, very rapid

Anaerobic
1103 ± 50
sedimentation

14


3.4.1.2. Evaluation of activated sludge particle size
Time
(days)

Anaerobic

Anoxic

Aerobic

12,11329 µm

13,57996 µm

20,44160 µm

14,13µ𝑚

82,88 µm

163,55µ𝑚

14,12941 µm

14,32089 µm

67,01550 µm

30

90

180

Figure 3.27: Spectral size distribution of activated sludge
3.4.1.3. Survey of biological polymer content
Conducting SEPS and BEPS content survey for 6 months and give
results shown in Figure 3.28; 3.29; 3.30:
Proteins
Pollysaccharides
Total

0.8

Proteins
Pollysaccharides
Total

1.0

0.7
0.8

0.5

BEPS (mg/g)

SEPS (mg/g)

0.6

0.4
0.3
0.2

0.6

0.4

0.2

0.1
0.0

0.0
T1

T2

T3

T4

T5

T1

T6

T2

T3

T4

T5

T6

Thoi gian

Thoi gian

b
a
Figure 3.28: Polymer content of anaerobic tanks: SEPS (a) and BEPS (b)
15


Proteins
Pollysaccharides
Total

Proteins
Pollysaccharides
Total

0.7

0.6
0.6

0.5

BEPS (mg/g)

SEPS (mg/g)

0.5

0.4

0.3

0.4
0.3
0.2

0.2

0.1

0.1

0.0
T1

0.0
T1

T2

T3

T4

T5

T2

T3

T6

T4

T5

T6

Thoi gian

Thoi gian

a
b
Figure 3.29: Polymer content in anoxic tanks: SEPS (a) and BEPS (b)
Proteins
Pollysaccharides
Total

Proteins
Pollysaccharides
Total

0.40

0.6

0.35

0.5

BEPS (mg/g)

SEPS (mg/g)

0.30
0.25
0.20
0.15

0.4

0.3

0.2

0.10
0.1

0.05
0.0
T1

0.00
T1

T2

T3

T4

T5

T2

T3

T6

T4

T5

T6

Thoi gian

Thoi gian

a
b
Figure 3.30: Polymer content of aerobic tank: SEPS (a) and BEPS (b)
3.4.2. Treatment of TNT by A2O-MBBR method
3.4.2.1. Evaluate the processing efficiency of A2O-MBBR system
The results of monitoring the change of pH in the reaction tanks are
shown in Figure 3.31.
8

pH

7

6

5

0

5

pH influence

%(3)

pH Ky Khi

%(4)

10

15

20

25

30

Time (day)

Figure 3.31: The change of pH at the reaction tank
The efficiency of wastewater treatment containing TNT by the
independent A2O-MBBR method is shown in Figure 3.32; 3.33 as
follows:
16


25

0

20

20

4.5

10

60

Remove
Vao
Ra

5

3.5
3.0

Ky Khi
Thieu khi
Hieu Khi

2.5

Abs

40

TNT removal (%)

15

TNT removal (%)

TNT concentration ( mg/L)

4.0

2.0
1.5

80

1.0
0

0

5

10

15

20

25

30

100

0.5

Time (day)

0.0
200

250

300

350

400

Wave

Figure 3.32: TNT removal
efficiency by A2O - MBBR system Figure 3:33: The transformation of
substances in A2O-MBBR system
Treatment efficiency of COD and NH4+
300

50
45

B

C

250

200

NH4-N(mg/l)

COD(mg/l)

40

IN
EN

150

Before
After

35
30
25
20

100

15
50

0

2

4

6

8

10

12

14

10

16

0

Times

2

4

6

8

10

12

14

16

Times

Figure 3.34: COD removal
Figure 3.35: Ammonium
efficiency
removal efficiency
3.4.3. Combining the method of internal electrolysis and A2OMBBR
3.4.3.1. COD removal efficiency
COD treatment results of the reaction system are presented in Figure
3.36:
120
110
100
90

COD mg/L

80
70
60

50
40
30
20
10
0

0

10

20

30

40

50

60

70

80

90

Time (day)

Figure 3.36: COD removal efficiency on A2O-MBBR system

17


3.4.3.2. Efficient treatment of NH4
NH4 treatment results are presented in Figure 3.37:
35
30

NH4(mg/l)

25
20

15
Pre-treat
10
Post-treat
5
0
0

20

40

60

80

Time(day)

Figure 3. 37. NH4 treatment efficiency of A2O-MBBR
3.4.3.3. TNT treatment efficiency
Through internal electrolysis process, TNT has been completely
decomposed, however, we still tested the TNT content in A2OMBBR system by high-pressure liquid chromatography and the
results shown in Figure 3.38:

c
b
a
Figure 3.38: HPLC spectrum of TNT in anaerobic tanks (a); anoxic (b);
aerobic (c)
Table 3.3: Efficiency before and after electrolysis treatment
Internal
A2OPre-treat
Post-treat
electrolytic
MBBR
COD (mg/l) 220 - 270
85 - 110
33 -38
86 – 89 %
TNT (mg/l) 95 – 106,4
0
0
100
BOD5/COD 0,18 – 0,2 0, 55 – 0,56 0,29 -0,5
+
NH4 (mg/l)

23 - 45
18 - 32
5,8 -7,9
73- 82
pH
5
6,5 – 6,6
6,5-7,2
Thus, the process of combining the internal electrolysis method
and A2O-MBBR to treat TNT and NH4NO3 in the actual wastewater
samples at the factory were successful, in which the efficiency of TNT,
COD and NH4 removal, respectively were 100%, 86 - 89%, 73-85%.
18


3.4.4. Microorganism diversity in A2O-MBBR system
The results showed that the microorganism in the A2O-MBBR system
treating TNT mainly consists of 7 genera: Candida, Bacillus,
Burkholderia, Chryseobacterium, Novosphingobium, Pseudomonas
and Trichosporon, 8 species. In which there are 02 strains can be new,
namely: Novosphingobium sp. (HK1-II, HK1-III) have 97.4-97.92%
similarity to Novosphingobium sediminicola. Trichosporon sp. (HK2II, TK2-II and HK2-III) have 97.7% similarity to middelhonenii.
0.005
T

B. puraquae_CAMPA
B. diffusa_R-15930T_AM747629
T
_CP000442
67 B. ambifaria_AMMD

T
B. cenocepacia_LMG
87
B. lata_383T_CP000150
B. arboris_R-24201T_AM747630
T
53 B. contaminans LMG 23361 _LASD01000006
TK3-II
80
KK1-II_
74
TK1-III
58
TK3-III
KK2-III
B. metallica_R-16017T_AM747632
B. anthina_R-4183T_AJ420880
seminalis_R-24196T_AM747631
50 B.cepacia_ATCC 25416T_AXBO01000009
B.territorii_LMG28158 T_LK023503
B.vietnamiensis_LMG 10929T_CP009631
B.multivorans_ATCC BAAT
B.dolosa_LMG
18943T_JX986970
247
_ALIW01000278
T
51 B.latens_R-5630 _AM747628
B. mesoacidophila_ATCC 31433T_CP020739
B. ubonensis_CIP 107078T_EU024179

88
B. stagnalis_LMG 28156T_LK023502
B. stabilis_ATCC BAA-67T_CP016444
51
T
95 B. pyrrocinia_DSM 10685 _CP011503
B. humptydooensis_MSMB43T_CP01338
B. rinojensis_A396T_KF650996
B. pseudomultivorans_LMG 26883T_HE962386
61
B. glumae_LMG 2196T_AMRF01000003
B. gladioli_NBRC 13700TT_BBJG01000151
65
B. plantarii_ATCC 43733 _CP007212
73
B. singularis_LMG 28154T_FXAN01000134
B. thailandensis_E264T_CP000086
63
B. mallei_ATCC 23344T_CP000011
50
B. pseudomallei_ATCC
23343T_CWJA01000021
99
T
B. oklahomensis_C6786 _ABBG010005
B. alpina_PO-04-17-38T_JF763852

Figure 3.38: Phylogeny of TK3-II, KK1-II, TK1-II, TK1-III, TK3-III
and KK2-III, that close relative in Species of in Burkholderia genus.
B. alpine PO-04-17-38T_JF763852 is extrinsic group, bootstrap

values> 50% are shown on the tree, bar 0.005
19


0.01
T

B. dabaoshanensis_GSS04 _KJ818278
B. shackletonii_LMG
HK5-II
100
99 TK1-II
B. subtilis D7XPN1T_JHCA01000027
99
KK1-III
T
B. taiwanensis_FJAT-14571
_KF0405
T
53 100
60
B. salidurans_KNUC7312 _KX904715
T
B. onubensis_0911MAR22V3
_NSEB010
B. timonensis_10403023T_CAET01000
50 72
T
B. sinesaloumensis_T P3516 _LT732529
96

84 B. humi_LMG 22167T _AJ627210
B. endophyticus_2DT _AF295302
T
B. filamentosus_SGD-14
_KF265351
100
T
B. manusensis_Ma50-5
_MF582328
T
60
B. kexueae_Ma50-5 _MF582327
T
B. carboniphilus_JCM 9731
_AB021182
B. seohaeanensis_BH724T_AY667495
T
B. halosaccharovorans_E33
_HQ4334
T
74
B. herbersteinensis_D-1-5a
_AJ781
T
B. depressus_BZ1 _KP259553
T
B. purgationiresistens_DS22
_FR66
T
70

B. korlensis_ZLC-26
_EU603328
T
B. dakarensis_ P3515 _LT707409
T
B. circulans_ATCC 4513
_AY724690
T
B. oryzisoli_1DS3-10 _KT886063
88
95
B. endozanthoxylicus_1404T_KX8651
B. drentensis_LMG 2183T_AJ542506
Ornithinibacillus contaminans CCUG 53201TFN597064

Figure 3.39: Phylogeny of HK5-II, TK1-II và KK1-III, that close
relative in Species of Bacillus genus. Ornithinibacillus contaminans
CCUG 53201TFN597064 is extrinsic group, bootstrap values> 50%
are shown on the tree, bar 0.01

73

100
68

99

93

100 P.aeruginosa_JCM 5962T_BAMA01000316

HK2-III-5
88 KK2_II
P. indicaT_ NBRC 103045T_BDAC01000046
P. furukawaii_KF77 _AJMR01000229
P. otitidis_MCC10330T_AY953147T
P. resinovorans_LMG 2274 _Z76668
P. oryzae_ KCTC 32247T_LT629751
P. guangdongensis_CCTCC AB 2012022T_LT629780
P. sagittaria_ JCM 18195T_FOXM01000044
100
P.18195T_FOXM01000044
linyingensis_LYBRD3-7T_HM24614
pharmacofabricae_ZYSR67-Z_KX91
P. fluvialis_ASS-1T_NMQV01000040
P. glareae_KMM 9500T_LC011944
P. guariconensis_ LMG 27394T_FMYX01000029
P. plecoglossicida_ NBRC 103162T_BBIV01000080
Azotobacter_beijerinckii ATCCT 19360_AJ308319

Figure 3.40: Phylogeny of HK2-III, TK2-II, that close relative in
Species of Pseudomonas genus. Azotobacter_beijerinckii ATCCT
19360_AJ308319 is extrinsic group, bootstrap values> 50% are
shown on the tree, bar 0.005.

20


0.01
C. vietnamense_GIMN1.005T_HM21241
C. aquifrigidense_CW9T_EF644913

59
C. flavum_CW-E_EF154516
C. arthrosphaerae_CC-VM-7T_MAYG01
Chryseobacterium_gleum_ATCC 35910T_ACKQ01000057
68
TK5-II
99
100 TK5-III
C. indologenes_ NBRC 14944T_BAVL01000024
C. joostei_DSM 16927T_jgi.1096615
61
C. gallinarum_DSM 27622T_CP009928
85
C. contaminans_DSM 23361T_LASD01000006
58
C. rhizoplanae_JM-534T_KP033261
C. viscerum_687B-08T_FR871426
C. sediminis_IMT-174T_KR349467
Chryseobacterium piscium_LMG 23089T_AM040439
79

Figure 3.41: Phylogeny of TK5-II. TK5-III, that close relative in
Species of Chryseobacterium genus. Chryseobacterium
piscium_LMG 23089T_AM040439 is extrinsic group, bootstrap
values> 50% are shown on the tree, bar 0.01.
N._oryzae NR_147755_T
N. humi R1-4TKY658458
N. sediminicola AH51FJ177534T
79
HK4-II

100
100 HK4-III
N. subterraneum_DSM12447_T__JRVC0
100
N. aromaticivorans_CP000248_DSM12
N. fontis LN890293T
N.
naphthalenivorans
NBRC_02051T
51
N.
barchaimii_KQ130454T
84
79
N. gossypii KP657488T
67
N._guangzhouense KX215153T
HK1-II
100 HK1-III
N. arvoryzae HF548596T
Blastomonas_natatoria_AB024288
72

Figure 3.42: Phylogeny of HK4-II, HK4-III, HK1-II VÀ HK1-II, that
close relative in Species of Novosphingobium genus.
Blastomonas_natatoria_AB024288 is extrinsic group, bootstrap
values> 50% are shown on the tree, bar 0.01.

21

0.05
100

100

100

Candida tropicalis KF281607
Candida dubliniensis MH591468
HK3-III
100
HK3_II
87 TK2-III
56 Trichosporon cutaneum
100 AB305103
Trichosporon mucoides
67 AB305104
Trichosporon dermatis
Trichosporon terricola
HM802130
99
Trichosporon
AB086382 middelhovenii
100 HK2-III
AB180198
TK2-II
100 HK2-II
Saccharomyces cerevisiae

Figure 3.43: Phylogeny of HK3-II, HK3-III, TK2-III, HK2-III, TK2-II
và HK2-II, that close relative in Species of Candida và Trichosporon
genus. Saccharomyces cerevisiae DAOM216365 is extrinsic group,
bootstrap values> 50% are shown on the tree, bar 0.05.
3.5. Design and operate testing of TNT's pilot wastewater
treatment system at Z121.
Pilot system to treat wastewater contaminated with TNT, NH4NO3 is
located at the wastewater treatment station of Factory 4, Enterprise
121 with a capacity of 250 liters/day and night. This system has run
the trial continuously for 40 days
Table 3.4: Results of TNT analysis during the test
TNT TCVN/QS
No. Name
(mg/l) 658:2012
Untreated waste water
96
1. Wastewater after internal electrolysis treatment KPH
Waste water after A2O-MBBR treatment
KPH
Untreated waste water
115
2. Wastewater after internal electrolysis treatment KPH
Waste water after A2O-MBBR treatment
KPH
0,5
Untreated waste water
36
3. Wastewater after internal electrolysis treatment KPH
Waste water after A2O-MBBR treatment
KPH

Untreated waste water
85
4. Wastewater after internal electrolysis treatment KPH
Waste water after A2O-MBBR treatment
KPH

22


Thus, through the process of pilot testing practice shows that: The
internal electrolytic treatment system combining A2O-MBBR system
has high treatment efficiency, the TNT, COD, BOD5, NH4 + all meet
QCVN 40: 2011 / BTNMT.
CONCLUSION
(1) Successfully fabricated bimetallic Fe/Cu electrolytic internal
materials with average size of 100 nm, potential E0 = 0.777 V to
replace Fe/C materials. In electrolyte solution pH=3 with the TNT
concentration of 100 mg/L corrosive line reaches 14.85*10-6 A/cm2
and corrosion speed is 8. 87*10-2 mm year.
(2) Some kinetic characteristics of internal electrolytic reactions on
bimetal Fe / Cu nanomaterials. The reaction rate of TNT
decomposition over time follows the rules of first order reaction
assumption in 90 minutes and has an activation energy of Ea = 26.99
kJ/mol. This process is dominated by diffusion domain. The
mechanism of TNT decomposition has been shown that: TNT is
reduced on the cathode surface by electrons received from Fe
corrosion and is oxidized by Fenton reaction in the electrolyte
solution. The relationship between corrosion line, Fe ion generation
rate and TNT treatment efficiency was determined based on reaction
time. Determined the K rate constants of the influencing factors in the

electrolytic reaction.
(3) The specifications for TNT treatment are established by internal
electrolysis method using bimetallic Fe/Cu nanomaterials. The
specifications are optimized by Experimental Box - Benken method
and are selected as: pH 3; shaking speed of 120 rpm; time 180
minutes; Fe/Cu content of 50 g/L; at 30oC, with a concentration of
TNT 100 mg/L, so the treatment efficiency reaches 98.29%. The
technical process is experimented by laboratory model and Pilot
model in the factory
(4) The technical parameters of A2O-MBBR method to treat
wastewater TNT are established directly or indirectly through
pretreatment by internal electrolysis method. Technical process is
tested by laboratory model and Pilot model in the field.
(5) Microorganism diversity and species variation of A2O-MBBR
system are evaluated during treatment of TNT . The microorganism in
23