Q&As about spiral heat exchangers
Q: What is a spiral heat exchanger?
A: A spiral heat exchanger is made up of two separate, fully welded, concentric channels for the hot and cold flows. A spiral heat exchanger is highly compact and the ideal choice for very fouling applications.
Q: What is the self-cleaning effect in a spiral heat exchanger?
A: The single-channel geometry of a spiral heat exchanger means the cross-section of a channel is reduced if fouling starts to build up in it. This causes the local pressure and flow velocity to increase since the entire flow must pass through a narrower channel, and eventually the force of the fluid flushes away the accumulated deposits. Alfa Laval refers to this as the SelfClean™ design.
Q: How to prevent fouling in a spiral heat exchanger?
A: The single-channel design gives a spiral heat exchanger a self-cleaning effect, which naturally prevents fouling and clogging, and makes it very suitable for sludges, emulsions, slurries, and fibre/particle-loaded liquids.
Q: How to clean a spiral heat exchanger?
A: A spiral heat exchanger can either be cleaned chemically or mechanically. By opening the covers of a spiral heat exchanger, the heat transfer surface is fully accessible for high-pressure waterjet cleaning.
Q: How much do spiral heat exchangers cost?
A: Spiral heat exchangers come in sizes from 1 m2 to 1,000 m2 and can be anything from off-the-shelf products to fully customized units in exotic materials, meaning prices vary largely. In any case, a spiral heat exchanger is a very competitive solution with a short payback time for fouling applications, considering the high uptime and low OPEX.
Q: What industries use spiral heat exchanger?
A: A spiral heat exchanger is suitable in all industries handling challenging fluids such as sludges, emulsions, slurries, fibre/particle-loaded liquids, viscous or very fouling fluids. Spiral heat exchangers are widely used in oil refining, minerals and mining, pulp and paper, petrochemicals and chemicals production, vegetable oil refining, and waste-water treatment.
Q: What are the different types of spiral heat exchanger?
A: Spiral heat exchangers are generally classified into four types depending on their designs (channels, position of nozzles, fluid distribution inside the unit, etc.). Type 1 and 3 are liquid/liquid heat exchangers suitable for fouling duties (Alfa Laval SpiralPro). Type 2 and 4 are mainly used in condensing applications (Alfa Laval SpiralCond).