8 replies to this topic

[shawkat06]

Dear All,

 

I am involved in one of the project as attached.

 

what will be the consequences if i routed back the return line (32") directly to cooling tower basin instead of return header.

sketch is attached for more detail.

 

Kindly advise me your expert opinions 

 

Thanks in advance

 

Shawkat

Process Engineer

Attached Files

•  Project Summary.pdf   2.69MB   37 downloads

[Pilesar]

One consequence of routing the return line to the cooling tower basin would be proportionally warmer cooling water supplied from the cooling tower to all users. This has a cost for the cooling water users which may be substantial, but difficult to calculate. With less back pressure for the return line, the flow to Aminat would increase and the flow to the other destinations may decrease slightly but probably not much because of the shape of the pump curves. Have you considered flowing the Aminat return into its own distribution header on to the top deck of the tower? That way the tower fill would not be bypassed.

[Saml]

There is something that I don't understand in the justification of the project. What do you mean by "one more cooling tower cell is put into operation which cost more than return back from Aminat".

 

I cannot imagine how a fan electricity consumption can justify a new piping. Lets say that an additional fan uses 50 kW . As far as I understand the cost of electricity in Saudi Arabia is around 30-35 USD/MWh,what means 14000 USD dollars per year if you run it 24/7/365. Anything you do with 32 inches pipe will cost several times that.

[shawkat06]

Dear Saml,

 

Thanks for you feedback.

 

This condition not only forced us to put one more cell into operation but also putting load on CTS pumps and need one extra pump to run.

 

Regards

Shawkat 

[shawkat06]

Dear Pilesar,

 

Thanks for your valuable inputs.

 

Actually i studied the consequences of proportional warming of cooling tower basin water, this will be slightly problematic during high humidity. But in case of high humidity we are running all cells and all pumps which will overcome this problem.

 

I will also look into your option "Have you considered flowing the Aminat return into its own distribution header on to the top deck of the tower? That way the tower fill would not be bypassed."

 

  Regards  

Shawkat

[breizh]

Hi ,

Just curious how do you manage the blow down on your system ?

Can it be on the return line from Aminat , to reduce the quantity of hot water you want to add to the basin or to install a smaller separate return line to the cooling towers header ?

hope this is helping you.

Breizh

[shawkat06]

Hi Breizh,

 

Blow down is managed by analyzer controller (conductivity and micros) on CT-Supply Header.

 

Would you please discuss in detail "Can it be on the return line from Aminat"

 

Thanks

 

Shawkat

[breizh]

hi ,

The blow down should be on the return line of your process where the temperature is high , before adding fresh chemicals to protect your system and make up water . If on supply header , you are loosing cold water and chemicals ,

Having said that , you may consider the point above to modify the  location of the continuous blow down ( if this is not the case) which will lead to a smaller line back to cooling towers .

In other words I'm proposing you to install the blow down on the Aminat return line .

 

Hope this is helping you .

 

Breizh

Edited by breizh, 05 March 2018 - 03:41 AM.

[shawkat06]

Hi Breizh,

 

We have both option for blow down but currently we are using supply header due to certain limitation.

 

I will do complete study for your option. thanks for your feedback.

 

Regards

 

Shawkat