In a combined cycle plant or waste-to-energy plant, upon turbine trip, the high pressure steam from the steam generator bypasses the steam turbine, is attemperated in a pressure reducing de-superheating valve and condensed in the main condenser. In certain instances, the bypass steam is required to be condensed in a separate bypass condenser.

Horizontal Bypass Condenser

Vertical Bypass Condenser

The performance requirements for the bypass condenser depends on the thermal-hydraulic architecture of the power plant. Certain bypass condensers require subcooling of shellside condensate in the manner of a feedwater heater. In another respect, circulating water flows through the tubeside of the bypass condenser emulates the flow arrangement in a surface condenser. The bypass condenser is thus a hybrid heat exchanger resembling both a steam surface condenser and feedwater heater in certain aspects. A proper bypass condenser design therefore requires a careful symbiosis of the condenser and heater design concepts.

The bypass condenser can be designed to operate under a variety of conditions such as high pressure, low pressure, condensing only, condensing and subcooling, horizontal, vertical, channel up, channel down, constant pressure, constant level and a of combinations thereof.

Holtec customized designs offer unique solutions to the thermal and flow transients encountered during the startup and operation of bypass condensers.