removal of sulphates

[781078]

during an experiment with the removal of sulphate from waste water @ different temperature I used calcium and barium-the barium worked but the calcium didnt react at all-any ideas or relevant sites

 

[BertGielen]

Please give more details on your needs (flow, sulphate-concentration, other substances to be removed from this water, final use and desired specs after treatment)

Some rules of thumb:

Barium works, but is generally not recommended:
- cost
- potential environmental burden of water with traces of Ba (check with local authorities; typical emission limits for Ba are in range 2 - 10 mg/l).

For Ca-precipitation, check correct temperature. See FAQ on this forum.

Other processes than precipitation : check biological removal. (Biological removal is the option of choice of there is a simultaneous need for removal of metals).
Membrane methods, distillation, ... are methods you might not consider unless you really are forced to do so.