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How to select Heating and cooling utilities used in Chemical Industries ?- A comparison study.



as we all know that without utilities plants can not run..

so it is very important to study the utilities used in the chemical plants, mostly in the heat exchanger or any heating and cooling equipment selection of utilities plays important role...

So firstly what is Utilities??

Utility is inseparable part of process plant

It is not counted directly as a product, which leaves company premises. But ignoring them may have significant effect on overall profit

Input and Output from Process Plant


Hear some of the utilities are listed ..
  • Steam 
  • Cooling water 
  • Air 
  • Refrigerant 
  • Brine  
  • Hot oil  
  • Hydrogen  
  • Inert gas (Nitrogen, Helium, Argon) 
  • Electricity

etc... 

Now commonly as a cooling utility we have 2 option available 
1. Cooling Water
2. Cooling Air..

So now thing is how to select from this two?

so for that comparison is given below..

Cooling Water 
  • Higher Heat Transfer co-efficient compared air.
  • Highest temperature of cooling water is fixed by process requirement.
  • Smaller size of heat transfer equipment. 
  • Higher operating cost
  • Relatively lower temperature can be achieved
Air

  • Lower Heat Transfer co-efficient compared water. 
  • There is no upper limit for highest temperature, as water has it's limitation.
  • Larger size of heat transfer equipment
  • Lower operating cost
  • Freely available
and for heating utilities generally we are using Steam or Hot oil..

so hear also how to select from this two??

so for that comparison is given below..

Steam 

  • Saturated steam has higher heat transfer coefficient compared to hot oil. 
  • No pumping required for transportation
  • Smaller size of heat transfer equipment
  • Not recommended for application having temperature above 180°C

Hot Oil

  • Lower heat transfer coefficient compared to saturated steam
  • High pumping cost
  • Large size of heat transfer equipment
  • Recommended for application having temperature between 180 - 400°C

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Comments

  1. Victoria Martinez31 July 2019 at 05:04

    This guide is helpful. And it persuade me to maintain my HVAC unit. And take good care of this. Heating and Cooling Keswick

    ReplyDelete
  2. michaelbelow22 July 2022 at 08:04

    VERY INFORMATIVE ARTICLE. Thanks
    www.cosmopolitanmechanical.ca

    ReplyDelete

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