3 replies to this topic

[Sishyan]

I have a problem in sizing the cooling tower basin hold-up volume.

 

The cooling water circulation rate is 450 cu.mtr/hr.  For this flow rate, I would like to size a R.C.C. basin for hold-up of cooling water.  On what basis, I shall size the same.  Is there any thumb rule or formula to calculate the same.  

 

KRN

[breizh]

hi ,

You need to consider the volume of water to supply the different equipment ( headers and equipments) together with the NPSH of the pump(s) to prevent cavitation , the footprint of the basin being at minimum  the footprint of the towers .

Good to have some margin .

Good luck

Breizh 

Edited by breizh, 03 July 2020 - 11:55 PM.

[Sishyan]

Hi

 

Thanks for your response.  Still, my query remains unanswered. 

 

I want to go for RCC sump, on top of which, the cooling tower will be mounted.

 

The basin volume shall be sufficient enough to prevent starvation of pumps as well as overflow of return water from the system.  The foot print of the floor area depends upon the volume it shall hold and it cannot be smaller than the cooling tower area as given by vendor.  How to calculate the basin hold-up volume based on circulation rate or system volume.  

 

I need to know the sizing basis - "so many times of the system volume" or "so many minutes of the circulation rate"

 

Is there any guidelines by CTI or Good Engineering Practice

 

Thanks once again.

 

KRN

[breizh]

Hi,

Information from a reputable engineering company : 

 

"The volume in the cold water basin (including pump suction bay, if

needed) shall allow for a minimum holdup of 10 minutes based on

design circulating flow and normal operating water level. Typical

water depths in the basin are 3 - 4 feet." 

 

Good luck

Breizh