Packaged Units/skids - FRECO | ADCA

ADCA ADCATherm FRECO – Flash Steam Heat Recovery Unit

The FRECO is a skid-mounted unit designed for heat recovery from flash steam, hot condensate, or a combination of both. It is primarily used in steam boiler rooms for preheating continuous water flow, such as make-up water to the feedwater system.

Operating Principle

The returning condensate is expanded in a flash vessel. The generated flash steam and remaining hot condensate are directed to separate heat exchangers, where they preheat pressurized feedwater before the economizer or direct entry into the boiler.

The setup is installed downstream of feed pumps, allowing preheating under pressure. This enables water to be heated above 100 °C without boiling, avoiding cavitation that would occur in an atmospheric tank at temperatures above 90 °C.

Media and Configuration

Suitable media:

• flash steam,
• saturated auxiliary steam,
• hot condensate,
• feedwater,
• compatible industrial fluids, depending on construction materials.

The typical setup may include a flash vessel, heat exchangers, steam pressure reducing station, pressure/temperature instruments, isolation valves, steam traps, and a bypass from cold water to hot water.

Critical Design Points

For sizing, the following are required:

• condensate flow and temperature,
• make-up water flow and temperature,
• operating pressures,
• boiler capacity and operating pressure,
• available steam pressure,
• need for atmospheric venting to prevent backpressure increase in condensate return.

In non-continuous consumption scenarios, control for recirculation, relief valves, or additional protections is required due to the risk of overheating and overpressure in the heat exchangers.

FAQ

Does it replace a condensate return unit?
No. It recovers heat before or parallel to the final condensate return to the tank.

When is a pressure reducer required?
When steam pressure needs stabilization for controlled thermal operation of the unit.