DRINKING WATER – physicochemical removal of iron and manganese in enclosed filter
I have several questions:
I assume you inject air upstream of the first filter.
Have you performed raw water analyses and between the two filers according to the following parameters:
Iron and dissolved iron
Manganese and dissolved manganese
pH Eb, filter 1 water outlet and filter 2 water outlet:
What are the parameters used for washing the Mangagran filter (Flow washing, length of time, cycle, etc)
Why do you inject KMnO4 between the two filters?; Personally, I would stopor I would inject at the top of the first filter (especially to oxidize the iron) and I would use a lot less than the stoichiometry calculation so as not to have too high a concentration dosage.
Mangagran is very effective in eliminating manganese (even more so when it is dissolved); but you have to respect the contact time; and the pH (> 7). Normally you should get < 10 µg/l i.e., below quantifiable limit. We have this in all the WWTP that we have reconditioned with manganese dioxide;
I look forward to hearing your reply to try to find a solution. Bye;