Technical information - Compabloc heat exchanger

How does Compabloc work

Sitting at the core of every Compabloc is a stack of corrugated heat-transfer plates made of stainless steel or other corrosion-resistant materials, laser welded alternately to form channels.

The hot and the cold streams flow through alternate channels. Corrugated plates cause high turbulence, resulting in substantially higher heat transfer efficiency with a 50–80% smaller heat transfer area than comparable shell-and-tubes. Flow turbulence also reduces the build-up of fouling. The Compabloc’s unique plate design eliminates dead zones in the heat exchanger.

The two flows in a Compabloc can be configured as single pass, or as multiple pass by using baffles. The number of passes on the hot and cold side can be chosen independently, making it possible to optimize heat transfer even if flow rates on the different sides differ greatly. This unique flexibility means the Compabloc is always optimized for exactly the required duty. The baffles are made to withstand full vacuum, and can be rearranged if design conditions are changed in the future.

Compabloc units have a counter-current flow and can operate with a crossing temperature program (in a single unit), where the temperature approach is as close as 3°C (5.4°F), maximizing energy recovery. The small size and light weight makes it possible to install Compablocs anywhere, for instance at the top of distillation columns or suspended from support structures.

Compabloc unique features

Superior cleaning and extended performance 

Alfa Laval manufactures the Compabloc plate pack using advanced laser welding with a butt-to-butt weld joint technique known as C-Weld. This eliminates crevices or “dead zones” common in other bloc-type heat exchangers, where fouling can build up, leading to corrosion and failure.

The use of laser welding and the C-Weld joint design further ensure higher reliability than conventional weld techniques, such as lap weld joints or TIG welding, which are far more susceptible to mechanical stress and failure. The end result is increased reliability and serviceability for maximum uptime.

Fast and efficient flushing of fouling material 

Alfa Laval’s C-Weld manufacturing method creates open channels around all the edges of plates in the Compabloc plate pack. During mechanical or chemical cleaning, as well as in the course of regular operation, any fouling that occurs will move along the heat transfer surface and flow freely out of these channels at the plate boundary. This SmartClean design makes it possible to fully clean every plate in the unit, returning the Compabloc to like-new performance after maintenance.

The SmartClean channels, impossible on bloc-type heat exchangers manufactured with edge welding, makes regular cleaning of the Compabloc both simple and quick.

Confident, long-term performance under pressure 

Unlike traditional flat gasket designs, +Seal introduces the first fully confined graphite gasket in a bloc-type heat exchanger. This prevents the risk of media leaks at pressures as high as 60 bar, simplifies maintenance, and protects against overtightening and creeping.

This is part of our revolutionary new Compabloc+ and is the secret to reaching higher design pressures without compromising on safety.

Advanced design for higher pressures 

Compabloc plates feature a one-of-a-kind pattern with “half-pyramids” equally distributed across the plate in an X-shaped pattern. This adds rigidity that increases mechanical strength for superior resistance to elongation forces common in high-pressure applications. With this cleanable XCore pattern, certain Compabloc models can handle pressures up to 42 barg without compromising thermal performance.

6 considerations for your selection process

Discover the plate heat exchanger benefits of Alfa Laval Compabloc