using exhaust steam

[Anatol]

In some sectors, the opinion its that compounding is a waste of time with high speed high pressure (steam) engines. But the exhaust steam, say from a uniflow, still has a lot of energy in it. Does anyone know cases where that energy has been used to drive feedwater and/or oil pumps? Or would this get in the way of creation of the necessary condensation vacuum?

 

[john_reese]

Exhaust steam was often used in feedwater heaters.

 

[deverett]

On some of the ships I sailed in, the main engine was a triple expansion steamer and the exhaust from the LP cylinder was fed into a low pressure turbine to extract the maximum energy from the steam.

Dave
The Emerald Isle

 

[Charles Lamont]

In some sectors, the opinion its that compounding is a waste of time with high speed high pressure (steam) engines. But the exhaust steam, say from a uniflow, still has a lot of energy in it. Does anyone know cases where that energy has been used to drive feedwater and/or oil pumps? Or would this get in the way of creation of the necessary condensation vacuum?

Driving the auxilliaries with exhaust steam would mean (a) the low pressure would necessitate excessively large cylinders to work the auxilliaries (b) increased back-pressure (or less vacuum) on the main engine, reducing its efficiency.

 

[Anatol]

Driving the auxilliaries with exhaust steam would mean (a) the low pressure would necessitate excessively large cylinders to work the auxilliaries (b) increased back-pressure (or less vacuum) on the main engine, reducing its efficiency.

makes sense. So, aside from heating feed water, how do you scavenge energy from exhaust steam?

 

[Anatol]

the exhaust from the LP cylinder was fed into a low pressure turbine to extract the maximum energy from the steam.

wow, I'm surprised the turbine lasted on low pressure wet steam

 

[Mechanicboy]

makes sense. So, aside from heating feed water, how do you scavenge energy from exhaust steam?

Here is my Stuart D10 with preheater for feeding water.

[ame="https://m.youtube.com/watch?v=qCdJjcHjVNQ"]https://m.youtube.com/watch?v=qCdJjcHjVNQ[/ame]

 

[Anatol]

sweet!
so the exhaust steam is in a heat exchanger/jacket, it doesn't actually mix with the feed water? Why not? that would see much simpler.
BTW - that's the thickest cocacola I'v ever seen. Special Norwegian formulation for low temps?

 

[Mechanicboy]

sweet!
so the exhaust steam is in a heat exchanger/jacket, it doesn't actually mix with the feed water? Why not? that would see much simpler.
BTW - that's the thickest cocacola I'v ever seen. Special Norwegian formulation for low temps?

Inside the heater is a lot of thin copper tube where the feeding water is entering into and heat up by steam exhaust then come out as hot water to pump into the boiler.

The oil in Coca cola bottle ---> https://www.mobil.com/english-us/industrial/pds/glxxmobil-cylinder-oils

 

[Anatol]

"Mobil 600W Super Cylinder Oil is recommended for saturated and superheated steam up to a temperature of 260ºC. Mobil Extra Hecla Super Cylinder Oil and Mobil Extra Hecla Super Cylinder Oil Mineral may be used with superheated steam above 260ºC."
duly noted, thanks for the tip.

BTW, 'thickest cocacola' was joke.