2 replies to this topic

[Mahefalison]

Hi all,

 

I would like to know/calculate the minimum/maximum length of DN500 vent stack.

This is about a ferric sulphate process tank (atmospheric tank). We've got already all the input and design considerations about the whole process (nom pipe size, flow, out velocity, fluid, pressure...)

The only thing is how to determine the permissible height of the vent from the nozzle to the end. Or is there a

standard length corresponding to a specific nominal pipe size for venting systems.

 

Thank you for your help lovely people

 

[fallah]

Mahefalison,

 

For atmospheric tanks you can lengthen the vent line (with fixed size) up to a value wouldn't pressurize the tank due to wxcessive pressure drop...

Then, you should solve the compressible flow equation for pipe length with given pipe size, fluid type (almost air) and properties, fluid maximum flow rate, upstream pressure (tank design pressure) and downstream pressure (atmospheric pressure). To respect safety margin, you should consider lower length than calculated one almost equal to (or below) %95 of calculated length...

[Mahefalison]

Thanks for your guidance Fallah.

 

Mahefalison