×
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

calcuim hydroxid

calcuim hydroxid

calcuim hydroxid

(OP)
how to use calcuim hydroxide to increase pH in drinking water?

RE: calcuim hydroxid

(OP)
Dear IRstuff,

do we have to mix the solid poweder with water and dose it ? what about the temperature?

how we can make sure it will not precepitate at the buttom?

Do we need filter?

Do you have digram which can make the idea easier?

RE: calcuim hydroxid

Calcium hydroxide is difficult to handle. However, it is used on larger systems because lime is economical and sometimes for remineralization on desalination systems.

The type of feed systems varies with the size of the application which you have not stated. Hydrated lime is more commonly used because it is easier to handle than quicklime.

Here is a simplified description. On large systems, bulk hydrated lime is stored in a silo. The dry material is metered out into an agitated slurry tank to make a slurry of about 20% lime. This slurry tank is located directly below the silo.

This slurry is then diluted to approximaely 10-15% hydrated lime solution in an agitated application tank. The slurry is pumped from the application tank to the application point where it is mixed into the water flow.

The temperature of the water is only important in the need for freeze protection.

http://www.chemcosystems.net/hydrated_lime_system....

http://www.indachem.com/Documents/Stanco-removed/L...

RE: calcuim hydroxid

(OP)
Thanks bimr

Very important information

RE: calcuim hydroxid

I am not sure what your application is but I can give you my expereince in the municipcal water treatment field. I have installed 3 Stanco bulk storage silos in my career. In order to size the amount of hydrated lime (calcium hydroxide) you will have to figure out how much lime you will be using on a daily basis to achieve the pH increase you are looking for. From there you will be able to determine if you need to go with bulk silo storage or a small bagged type of system. Any system that you put in will requrie some type of rotary valve upstream of the screw feed device. Without the rotary valve you can potenitally flood the system with an uncontrolled movement of hyrated lime material.

A typical arrangement is to meter the lime into a mixing tank and dilute it with a constant volume of water. One then pumps it out of the mixing tank to the application point. This is much simpler. If you can, arrange it so that instead of using a pump have the slurry overflow the mixing tank and flow by gravity to the application point. Nothing is simpler than gravity. Anybody that has worked with lime will know that there is constant maintenace required on the pump and the piping. You will get calcium carbonate depostion on the interanl walls. Eventually you have to break it off or the pipe will plug solid. Therefore use rubber hose as opposed to solid pipe. With rubber hose you can "massage" the pipe and the calcium carbonate build up on the inner walls will crack off.



RE: calcuim hydroxid

My other recommendation is to get a bag of hydrated lime and make some slurry yourself. do all the different concentratons you want on it. Nothing better than to see and get a feel for what you are handling. Also go visit some installations

RE: calcuim hydroxid

(OP)
Dear quality time
Thank you very much
I will try it

RE: calcuim hydroxid

If you can Look at the following:

1. Pnuematically convey the hydrated lime from the main storage tank to the augering hopper/auger/mixing tank
2. Locate the augering hopper/auger/mixing tank over the process application point
3. The auger then flow paces and meters the lime into the mixing tank. The mixing tank is fed a constant flow of mixing water. Therefore the pH of the slurry will change if there is a change in process flow. The mixed slurry overflows into the process by gravity. Nothing simpler than that. Almost zero maintenance

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