5 replies to this topic

[MohammadHelmy]

Dear all,\

Happy to be a new member in this beloved website, and to be a friend of all of you.

I am working in an Egyptian refinery. The plant is located near a domestic water source, that is why we use the once-through cooling mechanism to cool our petroleum products.

To save resources, i have thought about converting our cooling mechanism to the "closed-loop" one, where an amount of water will be used in the plant to extract heat from products, and consequently this amount of heat (duty rejected) can be removed from water and so it can be reused in the plant.

Two ways can be used to achieve that target:

1- Construction of a cooling tower facility, whilst the plant has no sufficient area for the facility.

2- Using a refrigeration cycle using propane or Ethylene or a Mixed refrigerant.

 

I hesitate about the idea. Is it applicable?

Can Propane be used to remove heat from water to vaporize, and then Propane is to be condensed by water in the condenser?

I started to collect the required data.

 

Please, reply with any advices>>>>>>

[PingPong]

Quote

Can Propane be used to remove heat from water to vaporize, and then Propane is to be condensed by water in the condenser?

That would not solve much. If you really intend to use a refrigerant to cool water then the refrigerant should be condensed by air, otherwise you would only transfer the problem from one water source to another. And it would make more sense to use butane or pentane or ..., instead of propane.

 

However: using refrig to cool cooling water is very expensive, so in my opinion not realistic.

Chilled water is usually made by a Lithium Bromide system, but to to that for a complete refinery is not economical either.

 

Adding a cooling tower only makes sense if the cold water from the cooling tower is not warmer than the supply temperature of the cooling water you are presently using. Cooling tower water will typically be about 3 ^oC warmer than the wet bulb temperature of the air, so you can easily compare.

 

You should make a cooling water balance of the complex, indicating for all CW exchangers the duties, and inlet- and outlet-temperatures of the process streams as well as the cooling water streams.

[curious_cat]

Quote

 

 

To save resources, i have thought about converting our cooling mechanism to the "closed-loop" one

 

Which resources would you be saving? 

[MohammadHelmy]

curious_cat, on 25 Nov 2013 - 3:55 PM, said:

 

Quote

 

 

To save resources, i have thought about converting our cooling mechanism to the "closed-loop" one

 

Which resources would you be saving? 

 

By logic, i have talked about water which is used for cooling in a once through mechanism, so the resources to be saved in -by logic- "WATER". 

Thanks for your comment.

[MohammadHelmy]

PingPong, on 25 Nov 2013 - 3:33 PM, said:

 

Quote

Can Propane be used to remove heat from water to vaporize, and then Propane is to be condensed by water in the condenser?

That would not solve much. If you really intend to use a refrigerant to cool water then the refrigerant should be condensed by air, otherwise you would only transfer the problem from one water source to another. And it would make more sense to use butane or pentane or ..., instead of propane.

 

However: using refrig to cool cooling water is very expensive, so in my opinion not realistic.

Chilled water is usually made by a Lithium Bromide system, but to to that for a complete refinery is not economical either.

 

Adding a cooling tower only makes sense if the cold water from the cooling tower is not warmer than the supply temperature of the cooling water you are presently using. Cooling tower water will typically be about 3 ^oC warmer than the wet bulb temperature of the air, so you can easily compare.

 

You should make a cooling water balance of the complex, indicating for all CW exchangers the duties, and inlet- and outlet-temperatures of the process streams as well as the cooling water streams.

 

Thanks for your reply

[Profe]

Hi Mohammad

Some tips for your question.

If you already have a heat exchange system that uses water, why not use a cooling tower high efficiency and compact?, If the problem is the plot area, it may be possible to optimize the required area. The use of the cooling tower requires the use of makeup water, approximately 5-6% of the total inventory of cooling water. If you change the cooling system. What be done with the existing exchangers?
You have consulted with a cooling tower supplier for evaluation of the existing system? Or you make a pinch analysis with your utilities?

I think that will be useful.

Fausto

Edited by Profe, 02 December 2013 - 09:48 AM.