×
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

Detention tank design for water

Detention tank design for water

Detention tank design for water

(OP)
Please, give me advice how to design a detention tank for water.

RE: Detention tank design for water

You need to clarify this.  Are you talking about a settling basin to treat a water supply ?  Are you talking about a storm water detention pond or retention pond ?  If you hope to get an answer make your question more specific please and provide some details; especially numbers.

Good luck.

RE: Detention tank design for water

(OP)
This detention tank is simply a tank which is going to keep the water and the injected chemical for 30 sec. .
the water is feed water for ultra filtration skids.
Although the length of the tank is enough, I have to consider 3 or more baffle for better mixing.
My question is how can I calculate the head loss for pasing over the baffles and how much thickness for baffle should i consider?

Thanks

RE: Detention tank design for water

The detention tank will depend on your design flow rate. For example, if your flow rate is 100 Us gallons per minute, a 50 gallon tank will hold the water for half a minute (30sec). Calculate cubic feet per gallon (0.13368cubic feet per gallon x 50 gallons) = 6.684 cubic foot tank. Depending on your space requirements or restrictions, determine your tank dimensions. For example if you tank is 2 feet diameter (V=A x H), A=pid2/4, you tank height will be 2.13 feet high.

RE: Detention tank design for water

(OP)
thanks for your reply.
I know how to size the tank, what I am not sure about is how to calculate the pressure loss inside the tank when you have baffle inside.
I really appreciate your help.

RE: Detention tank design for water

I'm a structural guy, but I like to observe how the hydraulics are done.  What I've noticed is that the hydraulic designers like to do is to slow the flow down so much that any losses over the baffles are not significant.
Then they argue, flip coins and pull numbers out of thin air based on experience.  It usually comes out to a couple of inches.

RE: Detention tank design for water

It all comes down to the velocity gradient of the fluid and the minor losses as the water flows through the tank. You can then use Bernoulli's equation to estimate the headloss. Instead of baffels, consider using plastic media in the detention tank to increase mixing.  Depending on the type of media added, determine the reduced crossectional area of the vessel and calculate the velocity gradient.  Add minor losses created by fluid eddy currents.  In any case, I would estimate the amount of headloss would be small especially when compared to the UF needs.  

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