Steam Generation Calculation

[FAIZANYOUSUF]

Dear Experts,

I would like to ask you to correct my calculation and my interpretation if I am wrong. The question basically pertains to the increase in steam generation via increase in feed water temperature.

Currently, the feed water temperature is 85 C. I am thinking to increase it up to 95 C so that steam generation could be increased. The boiler is Waste Heat Recovery Boiler extracting energy from engine exhaust. The feed tank capacity is 2.7 MT. Calculation is as follows,

Energy saved there by increase feed water temperature by 10 C.

Q = 10 * 2700 * 4.186

Q = 113022 KJ

Now the steam pressure normally is 6.5 BAR. At this pressure, the specific ethalpy of steam is 2758.87 KJ/KG. Considering this, I would generate more steam of,

113022 / 2758.87 = 40 KG (approx.)

Which is very less as compare to my expectation. Please suggest am I correct?

Thanks.

 

[LittleInch]

Sounds about right to me.

The energy in 1kg of steam at 6.5 bar is HUGE compared to 1kg of water with a temp rise of 1 C - 2758 vs 4.1 using your figures.
Heating water is relatively easy compared to making steam

So yes it will help, but by an incredibly small amount.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[FAIZANYOUSUF]

Thanks