×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Well Water : Manganese Removal

Well Water : Manganese Removal

Well Water : Manganese Removal

(OP)
Dear All,

I have read some of the post on here with interest, but am still a little confused. Trying to design an Fe Mn removal plant. Design Criteria
         inlet          outlet
Fe     3.5mg/l       0.1 mg/l
Mn     0.15 mg/l   0.02 mg/l

Removing of iron is simple, but confused on removal of Mn. was thinking of having pH correction (>7.5) and oxidation step (Cl2) followed by contact tank provideing 30 mins detention time to alloww complete oxidation of iron. Then passing this through a pressure filter. My fear is that at these conditions the Mn wont be oxidised (requires much higher pH and contact time). Do i need to use MnO2 or greensand filter to ensure Mn oxidation. If so do i need to increase pH furhter?
What would be the optimum treatment? This is for a remote site in Lybia, so the use of biological filters, or membrane technology may not be appropriate, hence a basic, easy to work system would be ideal.
Many thanks team!!

RE: Well Water : Manganese Removal

increasing ph up to cca 9 will give immediate good results.

if this is potable water, high ph is not acceptable. chlorination + filtration (greensand) will work ok, but you need 3-4 times stechiometric chlorine dose for manganese.

0.02 mg/l mangane is quite low, we had this tested with Mn less than 0.04 mg/l consistently...  

RE: Well Water : Manganese Removal

Would have to disagree with Bjegovic. Although chlorine is somewhat more active than dissolved oxygen, the pH values required for complete oxidation are nearly as high as with air oxidation. You would need a pH of 10 to oxidize the manganese in 30 minutes.

Would recommend that you use a manganese greensand process. Note that if the free carbon dioxide of the raw water is high, it is advisable to remove it to prevent the manganese pickup from an exhausted bed.

 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources