Adequacy and Efficacy of Treatment Plant Treating Electronics Industry Wastewater with the parameters : BOD, COD, TSS, TDS, Heavy Metals, Nitrogen and Phosphate.
2. Objective of the Study
To experimentally check the adequacy and efficacy of
various treatment processes involved in the treatment
plant by calculating the design parameters at different
points.
2
3. Scope of the Study
• This experimental study focuses on types of treatment processes used by the
Electronics Industry in treating the effluent wastewater.
• Study aims to suggest positive changes, if any, in the processes for attaining
the maximum efficiency.
• For the treatment of wastewater this facility has 2 treatment facilities-
a) Effluent Treatment Plant (ETP)
b) Sewerage Treatment Plant (STP)
Our experimental study has chosen the Effluent Treatment Plant.
• An effluent treatment plant of a reputed MNC in the field of electronics
manufacturing is chosen. This company is in electronics manufacturing field in
India since 90s.
3
4. Design Basis
The following characteristics have been considered in the design of ETP-
Treatment Plant Details
Sr. No. Parameter Inlet Outlet
1 Flow (m3/hr) 10 10
2 pH 7-8 7-8
3 Fe (ppm) 32.11 <3
4 Zn (ppm) 277.2 <5
5 Mn (ppm) 6.2 <2
6 Pb (ppm) 3 <0.1
7 Cu (ppm) 0.3 <3
4
5. 5
Flow Diagram of the treatment Plant
C BUILDING
COLLECTION
TANK
SKIMMING
TANK
AERATION
TANK
REACTION
TANK
PRIMARY
CLARIFIER
HOLDING
TANK
EQUALIZATION
TANK
MULTI GRADE
FILTER
pH
CORRECTION
TANK
SECONDARY
CLARIFIER
OUTLET
Sludge
6. 6
Technical Data
Technical Data of the treatment plant is summarized below:
Sr. No. Description Size/Capacity Quantity Make
1 Collection cum oil removal tank 4.2m x 0.5m x 1.0m 1 No. RCC
2 Equalization tank 4.5m x 4.0m x 3.5m 1 No. RCC
3 pH tank 3.5m x 1.0m x 1.8m 1 No. RCC
4 Sludge sump 2.5m x 2.5m x 1.6m 1 No. RCC
5 Lime dosing tank 1.4m x 1.5m x 1.6m 2 No. RCC
6 Oil collection tank 1 m3 1 No. MS
7 Fume absorber - 1 No. MSRL
8 Sludge transfer Pumps 5 m3/ hour @10 MWC 2 No. CI
9 Reaction tank 2.0 m x 1.8m x 1.6m 1 No. RCC
10 Multi grade filter 1.0 dia x 23 m H.O.S 1 No. MS
11 Pipe oil skimmer 80 NB x 500 mm long 1 No. MSEP
12 High rate solids contact clarifier grade
mechanism
Suitable for 4.0 m dia 2 No. MSEP
13 Air compressor 0.25 m3 / hr 2 No. CI
14 Centrifuge 5 m3 / hr 1 No. CI
8. Parameters Considered
8
Various Parameters calculated in this study are as follows:
• pH
• Conductivity
• Dissolved Oxygen
• Total Dissolved Solids
• Total Suspended Solids
• Mixed Liquor Suspended Solids
• Sludge Volume Index
• Biological Oxygen Demand
• Chemical Oxygen Demand
• Ammonical Nitrogen
• Phosphate
• Oil and Grease
• Heavy Metals
9. Materials and Methodology
9
Sampling and Sample Preservation-
• All the experiments were performed according to the standard procedure established
by the regulatory bodies.
• Instruments used in the experiments were from the reputed companies and comply
with the necessary standards.
• Grab sampling has been done at different points of the treatment plant-
a. Inlet
b. Equalization Tank
c. Secondary Clarifier
d. Outlet
• Sampling was also done at the aeration tank for calculating the design parameters.
• One litre new PVC bottles were used for all samples taken. Sample bottles were
securely sealed following sampling and stored securely.
• The wastewater sample preserved to about 4 degrees Celsius.
10. Experiments Performed:
10
Sr.
No.
Parameter Method Instrument/Material Used
1 pH Electrometric Method Hach Portable Meter
Package with pH Electrode
2 Electrical Conductivity Direct Conductivity Method Hach Portable Meter
Package with Conductivity
probe
3 Dissolved Oxygen Direct DO Probe Method Hach Portable Meter
Package with DO probe
4 Total Dissolved Solids Direct TDS Method Hach Portable Meter
Package with TDS probe
5 Total Suspended Solids Gravimetric Whatman Filter Paper
6 Mixed Liquor Suspended
Solids
Gravimetric Whatman Filter Paper
7 Sludge Volume Index Volumetric followed by
gravimetric
Graduated Beaker
16. 16
Parameter Observed Value
Inlet Outlet
Oil and Grease (mg/L) 7.289 1.251
Heavy Metals (ppm)
a. Arsenic Lead
b. Iron
c. Selenium
d. Chromium
e. Lead
0.423 0.264
3.074 0.417
Not Detected Not Detected
0.253 0.003
0.321 0.205
18. 18
Design Parameters in the Aeration Tank
Sr. No. Parameter Resulting Value
1 Mixed Liquor Suspended Solids 3140 (mg/L)
2 Mixed Liquor Volatile Suspended Solids 2355 (mg/L)
3 Sludge Volume Index 128 (mg/L)
4 Yield Coefficient 0.492
5 Substrate Concentration 14.50 (mg/L)
6 Volume of the Aeration Tank 78 cubic mt.
19. Dissolved Oxygen level is also checked at the four corners of the aeration
tank and it is averaged as 4.19 mg/ L which is more than the minimum
level of DO required.
19
Sr. No Parameter Resulting Value
7 F/M ratio 0.101 kg BOD5
8 Detention Period 7.2 hrs.
9 Return Sludge Pumping 108 m3/day
20. 20
REMOVAL EFFICIENCIES
Parameter Efficiency (%)
Overall BOD Removal Efficiency 75.90
COD Removal Efficiency 72.95
TSS Removal Efficiency
a. Primary Clarifier
b. Secondary Clarifier
62.76
21.09
36.43
TDS Removal Efficiency 68.08
Ammonical Nitrogen Removal Efficiency 87.30
Phosphate Removal Efficiency 74.19
Oil and Gas Removal Efficiency 82.85
21. 21
Comparison of effluent discharge quality with the standards prescribed:
38.65
72.31
30
250
0
50
100
150
200
250
300
BOD COD
Standard(mg/L)
Parameters
Observed Values (Outlet)
CPCB Standard
BOD & COD
25. Conclusions from the Study
25
Results from the present study Adequacy and Efficacy of Treatment Plant
Treating Electronics Industry Wastewater has been discussed below-
• BOD and COD removal efficiency of the treatment plant found to be
75.09% and 72.95% respectively.
• Treatment plant is capable of removing oil and grease, ammonical
nitrogen and phosphate efficiently.
• pH at the Inlet is found to be more than the design basis. Therefore, a pH
correction unit should be installed.
• Suspended Solids removal efficiency at the Primary Clarifier is found to
be 21% and at the secondary clarifier it is 36%. Therefore, additional
requirements to be done for increasing the efficiency of the primary
clarifier which is quite below.
26. 26
• Treatment plant is efficient in removing heavy metals like Iron and
Chromium as the effluent values are below CPCB standards. But
plant is not efficiently removing heavy metals like Arsenic and Lead
(effluent values found above CPCB standards).
• Important design parameters of aeration tank MLSS and SVI are
found in the acceptable limit.
• Volume of the Aeration tank required for the suspended growth
process is less than the design volume of the tank.
• Plant is adequate in its processes in the removal of various harmful
objects but some necessary arrangements are to be done for making it
more efficient.
27. Recommendations
27
• In the concerned Effluent treatment plant volume of the aeration tank is
not adequate to meet the suspended growth process; therefore, its capacity
should be increased for better efficiency.
• Arsenic and lead content is beyond the acceptable limits which should be
further treated with tertiary treatment processes.
• There should also a policy to be formed for better management and
operation of the unit processes.
• There should be proper working of on-site testing lab which all available
instruments for proper monitoring.
28. • The impact of semiconductor, electronics and optoelectronic industries on
downstream perfluorinated chemical contamination in Taiwanese rivers by Angela
Yu-Chen Lin, Sri Chandana Panchangam, Chao-Chun Lo (page 1 and 8)
• Pollution assessment and heavy metal determination by AAS in waste water
collected from Kushtia industrial zone in Bangladesh by Rafiquel Islam, Jannat Al
Foisal, Hasanuzzaman, Musrat Rahman, Laisa Ahmed Lisa & Dipak Kumar Paul
(page 1,4& 8)
• Physico-chemical Investigations of Semiconductor Industrial Wastewater by Y.C.
Wong, V. Moganaragi and N.A. Atiqah (page 1,3,4&7)
• PERFORMANCE EVALUATION OF A COMMON EFFLUENT TREATMENT
PLANT TREATING TEXTILE WASTEWATERS IN INDIA by Anju Singh, Richa
Gautam and Swagat Kishore Mishra (page 1,3&10)
• Performance evaluation of effluent treatment plant of dairy industry by DIPALI H.
CHAIUDHARI* and R.M. DHOBLE (page 1,3,4 & 6)
References
28
29. 29
• Managing and Monitoring Effluent Treatment Plants by Mohidus Samad
Khan, Jerry Knapp, Alexandra Clemett, Matthew Chadwick, Mahbub
Mahmood and Moinul Islam Sharif (page 5,6,7,14,10 & 12)
• Electronics Manufacturing Report by World Bank
• Detection of heavy metals (Pb, Sb, Al, As) through atomic absorption
spectroscopy from drinking water by Afrasiab Khan Tareen, Imrana Niaz
Sultan (page 1,3 & 4)
• Guide Manual: Water and Wastewater Analysis by CPCB
• Performance Status of Common Effluent Treatment Plants in India by CPCB
• http://nptel.ac.in/courses/105104102/Lecture%2025.html