In-line Mixer after aeration for WWTP

[sadochemeng]

Hi All,
With new regulations, we have to decrease the floride concentration in the wastewater before giving recieving river. We will use ferric chloride to react with floride and we will have 2 solid products. We think to feed ferric chloride after aeration tank going to detention tank to settle. But we need a connector to the sludge pipeline(which has 35% solid and 65% water in it) for ferric chloride which will provide a uniform mixing of sludge water and ferric chloride. We dont want anything in pipeline that is why we cant have static in-line mixers, also not quills because we dont want pipeline to clog after a while. Do you know any equipment which will provide this kind of connection or how we can make enough turbulance at that connecting point to set a uniform mixing.
Thanks.

 

[bimr]

You should have the solution adequately mixed if you allow 4 90 degree bends after you inject the chemical feed.

 

[sadochemeng]

do you have any scientific explanation or source that I can look it up why it is like that? becasue I have to explain it to my supervisor...we kind have pressure issues too but I am sure if we find a efficient way to mix them then we can solve it...

 

[sadochemeng]

any more ideas for mixing? any scientific explanation for 4 90 degree bends?

 

[bpattengale]

Have you looked at venturi mixers?

http://www.transvac.co.uk/watertreatment.htm

Scroll down and look at the bottom one.

 

[bimr]

Don't have any documentation for the 4 90 degree elbow method. The method was told to me by a senior project engineer for a water treatment company many years ago. However, it would be simple to test the method with a dye solution.

 

[eahrens]

There are non-clog static mixers that will pass debris up to 25% the diameter of the pipe. They are used for sludge/polymer mixing. I know that Komax Systems makes one called a Hi-Pass. It was successful on our dewatering application.