×
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

Dechlorinaton

Dechlorinaton

Dechlorinaton

(OP)
I'm designing a small water treatment plant (150 m3/day) to remove Mn and Fe (very low levels in ground water source) using sodium hyplochlorite followed by greensand pressure filter.

To reactivate the filters I intend on using a 100 mg/L solution of NaOCl as per the green sand vendors recommendation.

My problem is ....to discharge the backwash water to the environment I need to have near non-detectable level of free residual chlorine (FRC).

I'm thinkg of using either ascorbic acid or sodium bisulphite to remove the removal the FRC but not sure on dosing rates?

Any suggestions?  

RE: Dechlorinaton

Caneng2002:

You have a variety of choices for dechlorination, though either ascorbic acid (at 2.5 parts to each part of chlorine) and sodium ascorbate (at 2.8 parts to each part of chlorine) are the most expensive in terms of product cost and treating cost. I would suggest staying with sodium bisulfite (at 1.45 parts to each part of chlorine) which will be the most cost-effective.

Make sure that you exceed the stoichiometric value for sodium bisulfite shown above by a small percentage to cover variations in minute-to-minute chlorine concentrations.

Orenda

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