Emalalheni (Witbank) South Africa
Phase 1: 2008
Phase 2: 2010
Phase 3: 2013
Acid mine drainage (by Aveng)
Aveng Water (Pty) Ltd
Potable water
BHP Billiton & Anglo American
50 MLD
The Emalahleni Water
Reclamation Plant, located in the Witbank coalfields of South Africa’s
Mpumalanga province, is the first and only Acid Mine Drainage (AMD) to potable
water treatment plant in the world. The ACD process is designed by Aveng. The desalination plant treats acidic,
saline mine waters to a South African National Standard (SANS) 0241 Class 0
potable water. Due to limited water resources, the Emalalheni Water Reclamation
Plant plays an important role in meeting the area’s increasing water demand and
environmental challenges.
The plant’s three-stage
membrane process treats AMD waters from coal mining operations. Multiple
ultrafiltration and reverse osmosis membrane systems operate in a series, which
offers water recovery rates of > 97 precent. First, a combination of two
CSIR processes, namely the limestone/lime neutralization and gypsum
crystallization processes, are used as pretreatment, followed by green sand
filters to remove residual manganese.
water quality parameter | units | feed water (95 percentile) | treated water |
pH | - | 2.7 | 6.0 - 9.0 |
Acidity |
mg/l as CaCo3 | 1050 | 0 |
Electrical conductivity |
mS/m |
460 | < 70 |
Total dissolved solids |
mg/l |
4930 | < 450 |
Calcium, Ca |
mg/l | 660 | < 80 |
Magnesium, Mg |
mg/l |
230 | < 30 |
Sodium, Na |
mg/l |
130 | < 100 |
Potassium, K |
mg/l | 13 | < 25 |
Sulfate, SO4 |
mg/l |
3090 | < 200 |
Choride, Cl |
mg/l |
70 | < 100 |
Iron, Fe |
mg/l | 210 | < 0.01 |
Manganese, Mn |
mg/l | 35 | < 0.05 |
Aluminium, Al |
mg/l | 40 | < 0.15 |
400 x Aquaflex 40 UF Module
695 x Aquaflex 55 UF Module