1. Water Treatment Management FOR Sustainable Industry
Green & Clean POSCO
Water Treatment Management
FOR Sustainable Industry
11.23
Hyo Seon Kim

2. Backgrounds Stable water supply for long term strategy
Strengthening of wastewater regulation
Increased needs for process water by expansion of steel production facility

3. Indirect Cooling Water
Water Balance
Recycling
Evaporation
Ground Water
1st Wastewater
Treatment
(end of each process)
Process
(Coke making,
Steel making,
Cold Rolling etc)
Process
Water Production
Dam Water
Reuse
Recirculation (98%)
Reuse
Reuse
Sewage, Rain water,
Indirect Cooling Water
Treatment
2nd(Final) Waste-
water
Treatment
Discharge
Discharge

4. Water Supply System Reservoir Ground water Mixing tank Settling Basin
River Water
Water Supply
Reused Water
Sand Filter
* Suspended solids are removed by coagulant addition and precipitated in the settling basin.
* The treated water is transported to each process unit

5. Water supply per day (㎥/day) Water Use per ton of steel
Water Supply and Quality
Water supply
Pohang Works
Water supply per day (㎥/day)
170,000
Water Use per ton of steel
(㎥/T-S) 4
Water quality
Pohang Worls
Turbidity (NTU)
< 1 Ca 40
Cl- 5

6. Wastewater Treatment Process 1st WWT Advanced WWT Final WWT Coke BET
Phenol, CN
Iron & Steel
Section
WWT
A/C Adsorption
NH4, zinc, CN
Hyungsan River BF
Biol. Ammonia Treatment
FINEX
NH4, SS
C/C F
Wire
SS, Oil
Rolling
Section
WWT
Cold Rolling
Acid, Oil, Metal
STS
F, Metal
Biol. Denitrification
Nang River
Electric
Acid, Oil, Metal
Plate
SS, Oil
Hot Rolling
SS, Oil

7. Wastewater Facilities
final WWT of Pohang
Denitrification WWT in STS
Activated carbon facility

8. Wastewater Effluent Quality Pohang Works Seongang WWT Apyeon WWT
Flowrate (㎥/day)
18,000
30,000
COD (mg/L) 16 9
SS (mg/L) 7
* Seongang - Upstream process including BF
* Apyeon – Down process including cold rolling mill

9. Rain Water Treatment Constructing Site Storage Pond Collecting Basin
Reuse
Water Way
Dscharge
Hyungsan
River
Rain Water
Reuse

10. Industrial Supply Water
Rain Water Treatment
Quality
Flowrate
(㎥/day)
COD (mg/L)
SS (mg/L)
44,000 8 5
Rain water reuse
(Unit : ㎥/day)
Usage
Pohang Works
Industrial Supply Water
1,900
Road Spray
9,000

11. Biological Sewage Treatment
Sewage Treatment System
Relay
Pit
Biological Sewage Treatment
Sewage
Sources
Pit
(Car)
Pit
(Pumping)
Reuse
- Toilets, Bathrooms,
- Restaurants, Laundry
* Sewage from over 600 sites containing bathroom, restaurant, laundry is collected through car and pumping into the relay pit and is transferred to the this facility.

12. Mixing to Process Water
Application of Reused Water
Road Spray
Mixing to Process Water
Slag Qquenching
Internal Supply
Others
* We are establishing strategic plan for maximizing water reuse and minimizing discharge such as re-evaluation of water quality standards for each process, increase of recycling ratio in cooling water system, and installation of reserve osmosis and so on.