LP Heater in Condenser

Can you provide a drawing or sketch?

It seems odd to heat a condenser, which is meant for cooling. However, if the heater is intended to heat some external process, it may act to capture some heat from the steam entering the condenser. (Such a heater would also be a condenser in series or parallel with the main condenser.)

Dear Mr. RG2,

It is known that in the condenser the Latent Heat of Steam is removed by circulating /cooling water, and the steam is condensed to 1/1600 of its volume, and comes to water phase. Theoritically, the condensate temp. and the temp. of the steam entering the condenser is the same (minor difference of radiation, if any is ignored)

The same condensate is going back to the Boiler, When there is no Temp.Difference how the incoming steam in the condenser will heat the condensate which is at the same temp. If it is other water or fluid, other than the same condensate, it is OK.

Pl. clarify.

DHAYANANDHAN.S

Just above the condenser coils, there is another set of coils which is the "U Tube" section of a heat exchanger. It is located in the upper area of the condenser where the steam coming from the LP Turbine's blading exhaust can readily pass over and through these tubes to remove additional latent heat in an effort to "heat the condensate passing through these tubes" before it passes to its next low pressure heater in the condensate section of the heat cycle. Being above the condenser coils, it is effectively a heater much like the other LP heaters. It has associated structural steel for a frame and also has a shell around these coils. There are directing channels which direct the flow of steam across these heaters. At the power plant where I work, we have 2 units rated 700 and 790 MW. Each unit has 2 LP Turbines and 2 LP heaters which reside one in each side of the compartmented condensers. Where most HP & LP Heaters have an extraction valve for extracting steam from the turbine, these have no isolation from the extraction steam. The last stage of the turbine is the extraction point. There main function is to increase the efficiency of the cycle. I hope this clears up the issue for you.

OK. Without access to a piping and instrumentation drawing:

• The job of the <...condenser...> in a <...Thermal Power plant...> is to pull a vacuum on the back end of the turbine to increase the power obtained from the same throughput of steam, thereby increasing efficiency. In cooling below 100degC, a vacuum is created.
• Were the vacuum to persist then it would not be possible to open the <...condenser...> vessel for maintenance access unless the temperature were raised beforehand to about 100degC, thereby releasing the vacuum.