Bottom cylindrical Tank Drainage systeme design (Beginner) 2

[drakkkko]

Dear All,

I have to design a drain in the bottom of carbón steel tank, but I never done this before so I need guidness in this one.

Tank dimension: Int diameter, 47 Ft. & Height 62,3 Ft

Fluid: Water with trace of hypochlorite

Original design it’s include a 6” nozzle for drain, but our client requires a full drainage, so we will keep that nozzle and add an drainage system.

Is there any Handbook for beginners, which could help to define proper α and β angles (See attached drawing

https://files.engineering.com/getfi...25-c913bd1200c2&file=Tank_Bottom_Drainage.jpg

), drain pipe length and Sump dimensión (volume) ?


Thanks in advance,

Best Regards.

 

[IFRs]

You should refer to the standard or code that the tank was originally designed to. In lieu of that try API 650 or AWWA D100. Both have default bottom slopes, nozzle details and sump dimensions.

 

[MJCronin]

Agree with IFRs ....

I do not like your design .... What keeps the fluid from rushing into the sump and draining the tank ?

Suggest that you consider something like this:

MJCronin
Sr. Process Engineer

 

[drakkkko]

Thank you both for your indications.
I have another doubt...for flat bottom Tanks...If I consider an x% slope ( for example 3% ) , is there a limits in that slope?..I mean a limits to Tank keep the flat bottom category.

Thanks in advance!

 

[MJCronin]

Upon second reading of your design requirements ..... I wish to change my suggestion

Your tank diameter is rather large for a coned bottom, point down configuration.

Another configuration to consider is "cone bottom, point up" (self explanatory)

With this kind of configuration, (with several drain nozzles around the tank shell) the foundation becomes easier

I do not believe that you need a 3% slope ...

MJCronin
Sr. Process Engineer

 

[drakkkko]

Thanks MJCronin !, in fact I was thinking in a single-slope bottom Tanks, with Slope of 1% , although in the picture you attached the Slope is 1/120...well I don't think I could have problem...I couldn't find in API 650 what is standard Slope for a single-slope bottom Tanks...

 

[IFRs]

Standard API 650 bottom slope is 1 inch in 120 inches. Besides cone-up, cone-down and flat bottoms, you can use a bottom that slopes uniformly from one side to the other - sometimes called a shovel slope.