This document summarizes a training program on environmental management strategies in the petroleum, petrochemical and fertilizer industries. It discusses various treatment technologies used by ONGC to treat produced water and effluents onshore and offshore. These include techniques like CPI, IGF, hydrocyclones and compact flotation units. It also highlights challenges in reservoir health management, promoting reuse and recycling, and developing new treatment technologies. ONGC's mangrove conservation and bioremediation projects are briefly described.

1. Training Programme
ONGC
on
“Recent trends in Environmental Management
strategies in Petroleum, Petrochemical and
Fertilizer Industry”
Sponsored By
Central Pollution Control Board
February 11-13, 2008
Venue: Continuing Education Center
Conference Hall
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2. Recent trends in environmental
management strategies in oil & gas
exploration & production
Dr A K Agnihotri
DGM (Chemistry)
ONGC

3. Water: Issues
• Nearly half of the world's people will live in
water-stressed areas by 2025 (WRI)
• Our population of 1 billion is going to double in
next twenty years
• Water resources have been exploited to the
extent possible
• No consideration to future generation
• Result: Grave threat to Sustainability
ONGC

4. Oil & Gas Industry
• Less water intensive process
• Aging of reservoir
• Produced Water
• Produced water Treatment
• Water Injection into reservoir/disposal
ONGC

5. ONGC: Treatment Facility
Onshore
21 ETPs treat about 43,000 m3/d of effluent
Offshore
15 PWCs handle about 1,00,000 m3/d of
produced water
ONGC

6. Discharge Standards for oil & Gas Industry
Sl No Parameter On-shore discharge Marine Discharge Offshore Discharge
1 pH 5.5 -9.0 5.5 -9.0 -
2 Oil & grease 10 10 40
3 Suspended solids 100 100 -
4 Total Dissolved Solids 2100 - -
5 BOD at 27°Cfor 3 days 30 30 -
6 COD 100 - -
7 Chlorides 600 - -
8 Sulphates 1000 - -
9 Phenolics 1.2 - -
10 Cyanides 0.2 0.005 * -
11 Sulphides 2.0 - -
12 Zinc 2 0.1 * -
13 Chromium (hexavalent) 0.1 - -
14 Chromium (Total) 1.0 0.1 * -
15 Copper 0.2 0.05 * -
16 Lead 0.1 0.05 * -
17 Mercury 0.01 0.01 * -
18 Nickel 3.0 0.1 * -
ONGC
mg/L
* The maximum individual pollutant concentration level in sea water within a distance of 50 meter from the discharge point.

7. Onshore ETPs
Treatment Technologies
• TPI/CPI
• DAF
• Elevated Settlers
• Biotowers
• Aeration Tank
• Sand/Activated Carbon Filters
ONGC

8. Typical Onshore Treatment Process
ONGC
Equalization Wash Tank
tank
TPI
Flash
Mix
DAF
Bio-tower
Aeration tank
Sand/Carbon
Pressure
Filters
Clarifier
Clarifier
Chemicals
Disposal

9. Offshore Effluent Treatment
Treatment Technologies
• CPI
• IGF
• Hydro cyclones
• Compact Flotation Unit
ONGC

10. Typical offshore Treatment Process
HP Separator Flash Vessel CPI
ONGC
IGF
Sump Caisson

11. Hydrocyclone
• Use centrifugal force
• High rate of flow
• No moving parts
• Removes oil drops of
size 10-15 micron
• Reduces oil upto 25 ppm
ONGC

12. EPCON Compact Flotation Unit
• Oil drops are made to agglomerate
to produce larger drops, creating a
oil layer at the top
• Separation is aided by gas flotation
effect caused by the release of
residual gas
• Efficiency may be enhanced by
introduction of external gas or
flocculating chemicals
• Residence time - 1 min max
• Size - 2 m3 approx
• Reduces oil to 15 – 20 mg/l
ONGC

13. Microbial Technology
• Bioremediation
• Microbial treatment of effluents
• Microbial Treatment for EOR
ONGC
API
Separator
BPC
reactor
BPC
secondary
reactor
Settling
chamber

14. BPC Bioreactor
ONGC

15. Challenges Ahead
• Reservoir health management
• Prominence for Reuse and Recycle
• Promotion of Research & development
• Promotion of new treatment technologies
• Management Commitment
ONGC

16. ONGC

17. ONGC

18. ONGC

19. ONGC

20. Mangrove Conservation
• In line with international practice of Biodiversity
conservation ONGC has embarked upon an
ambitious programme of mangrove conservation
& education.
• 5 Lac mangrove seedlings/plantation in Gandhar
area.
• Education & awareness drive about mangrove
conservation in Mumbai.
• This project is a joint project with Bombay
Natural History Society (BNHS) Mumbai
• Cost of the project is 2 crore.
ONGC

21. ONGC

22. ONGC

23. Bioremediation
• Bioremediation of oily sludge from tank cleaning
• Bioremediation of drill cuttings/Oily wastes
• 16000 Tonnes of Sludge is already bioremediated
& job is still going on.
ONGC