What treatment?
• Neutralization and partial desalination - essential for protection of the
environment and human health and,
• Complete desalination - drinking water needed during the next four years
Limestone handling and dosing system
Full-scale neutralization plants
•
Iluka Resources, Hamilton
•
Namakwa Sands, Lutzville
Fe(II)-removal with sequence batch operation
Parameter
Western Basin
Flow (Ml/d)
Chemical cost (R/m3)
Chemical cost (R/a)
Central Basin
Flow (Ml/d)
Chemical cost (R/m3)
Chemical cost (R/a)
Total
Flow (Ml/d)
Chemical cost (R/m3)
Chemical cost (R/m3)
Chemical cost (R/a)
Limestone
/lime
Only lime
33
33
1.02
3.02
36 300 000 12 300 000
56
56
1.07
3.19
65 200 000 21 900 000
89
89
1.05
3.12
101 500 000 34 200 000
Treatment at Grootvlei water (108 Ml/d)
• Grootvlei Mine where contains 100 mg/l iron(II) and 350 mg/l
alkalinity. Currently this water is treated at a cost of R3.7
million/month, using lime and oxygen.
• 100mg/l need to be oxidised in a more cost-effective way.
Desalination
• Need 400 Ml/d by 2014 in Gauteng
• Coal mining sector already produce 35 Ml/d drinking water from mine
water in Mpumalanga
CSIR ABC Desalination process
(Alkali-Barium-Calcium)
• Lime and/or CaS pre-treatment
• Barium treatment for SO4 removal
• Sludge processing
CaCO3 Ca(HS)2
Ca(OH)2
CO2
AMD
H2O
H2O
Coal
CaSO4
Mg(OH)2
MS
BaCO3
Sludge processing stage
CaCO3
Ca(HS)2
Ca(OH)2
CO2
BaSO4
CaCO3
Western Utilities Corporation pilot plant
to evaluate ABC process
TUT MBO process
(magnesium-barium-oxide)
• Metal removal with Mg(OH)2
• SO4 and Mg removal with Ba(OH)2
• Sludge processing
Mg(OH)2
Ba(OH)2
CO2
AMD
Treated
H 2O
BaSO4
Mg(OH)2
H 2O
Fe(OH)3
Al(OH)3
MnO2
H 2O
Coal
Ash
S
Ba(OH)2(aq)
Mg(OH)2
CaCO3
Soshanguve pilot plant
for freeze desalination
Ice filter
Heat exchangers
Refrigeration
unit
Ice production
Official launch – 25 October 2011 at 13:00 as Soshanguve Campus of TUT