2 replies to this topic

[ger_jacko]

Recently as i was reading the P&ID for my project, i came across two types of condensers namely, the trim condenser and the surface condenser.

I am aware that the surface condenser is usually installed after a turbine whereby the steam outlet from the turbine is condensed under a vacuum condition. This will help to improve the efficiency of the turbine. This can be done so because condensate has a lower enthalpy and thus the work done (=enthalpy difference between the inlet and outlet of turbine) will be greater. (please correct me if i'm wrong)

At the same time, i came across the word "Trim condenser". So my question is, what exactly does trim condenser do? Does it have the same function as the surface condenser?

[Chris Haslego]

In the context that you've used, the trim condenser is probably installed on the vent of the "main" or surface condenser. The vent coming from the surface condenser will have water vapor and air in it. The air is from minor leakages into the system under vacuum.

Commonly, a secondary or "trim" condenser is installed to remove additional water from the surface condenser vent and to further cool the vapor being sent to the vacuum system. The cooler the vapors that the vacuum system is pulling, the smaller it can be.

Essentially, this trim condenser is probably part of the vacuum system optimization.

[smalawi]

hi,

the term trim cooler is widley used in the refinning busniess to indicate a cooler designed to remove a small heat duty to satisfy a temperature spec from rundown or practical requirement.

for example out of the distillaiton column you will have your prodcut stream exchanging heat with the feed for heat intergration. then you will have a small duty left to cool the steam to proctical limits of the tank or to a safe temerature below its flash point. this is typically done by a "trim" cooler. most of these coolers uses water as a cooling medum and operatre in sensible heat/ sub colling the process fluid.

cheers,