Reverse Osmosis Brine Treatment

 

Project name: Pohang Water Reuse Facility

Location: Pohang, Korea
Technology: BBF
Capacity: 9,000 m3/d (2.4 MGD)
Operation: Since 2014

 

Existing Issues

  • Reverse osmosis plant produces high-quality water for industrial reuse with a concentrated byproduct: high-strength brine with 34 mg/L total nitrogen.
  • This brine discharge could be environmentally damaging to the densely populated surrounding area.
  • Biological denitrification is necessary during treatment.

 

BKT Solution

  • BBF was selected as the treatment system.

 

Process Description

  • Aerobic BBF reactors provide nitrification and organic removal.
  • Anaerobic BBF reactors provide denitrification.
  • A chemical precipitation system removes phosphorus.

 

Treatment Results

Influent
(mg/l)
Effluent
(mg/l)
BOD 7.4~11.2 (9.5) 5.3~9.5 (6.6)
COD 25.7~31.4 (28.4) 25.4~31.4 (27.2)
SS 1.0~3.0 (2.0) 2.0~4.0 (3.0)
TN 29.6~36.8 (34.3) 10.8~16.3 (13.1)
NH3-N 2.7~9.3 (5.6) 1.0~2.4 (1.8)
NO3-N 8.3~16.6 (12.4) 0.1~2.8 (1.4)
NO2-N 7.9~15.8 (10.8) 6.2~10.6 (8.7)
TP 0.54~1.17 (0.77) 0.65~0.94 (0.74)