5 replies to this topic

[Erica789]

Hello, i am doing internship in company.
In plant theres one coal fired boiler which produces steam of 9 kg/cm2.and this is distributed in all plants
Theres only on plant which requires steam at about 9 kg/cm2 and other three plants require steam at 3.5 kg/cm2.
So pressure is reduced using control valve.
So my que is: Is this energy loss that i am producing at 9 and using at 3.5 kg/cm2.

[Erica789]

One plant**

[Kiran T]

Hi Erica,

 

Steam has two type of heat. Latent heat & sensible heat.

 

Steam at lower pressure will have higher latent heat.

 

Steam is generated at high pressure at boiler station to reduce capital cost due to low specific volume.  For better idea you can compare latent heat @ 3 kg/cm2 & 9 kg/cm2 in steam table.

 

By reducing the pressure from 9 kg/cm2 to 3 kg/cm2, the total energy loss is 39 kj/kg, while latent heat will increase by 119 kj/kg. 

[Bobby Strain]

Erica,

       You are not losing anything. And there is not really enough pressure differential to drive a generator to generate electricity. So, move on to your next learning experience.

 

Bobby

[Erica789]

Thanks Bobby and Kiran.

[riven]

As said the pressure are low so there will not be much energy saving unless the tons/hr were high. The calculation and explanation are explained at the website below and i would suggest making your own excel sheet to work through to understand.

 

https://www4.eere.en...amo_steam_tool/