Spiral heat exchangers | Sondex/Danfoss | Philippopoulos s.a.
Spiral heat exchangers | Sondex/Danfoss | Philippopoulos s.a.

Spiral heat exchangers | Sondex/Danfoss

SONDEX® / Danfoss Spiral Heat Exchangers

SONDEX® SonSPV spiral heat exchangers utilize two helical flow channels instead of a tube bundle. This configuration is suitable for fluids with viscosity, solids, fibers, or increased fouling tendency, such as sludges, slurries, wastewater, and process streams with particulates.

Operating Principle

The spiral path creates a single-channel flow with increased shear stresses. When deposits begin to form, the local reduction in cross-section increases velocity and helps limit accumulation. This does not eliminate the need for cleaning but affects maintenance intervals depending on the medium.

Applications

Typical uses:

  • wastewater, biogas, and sludges,
  • pulp and cellulose fibers,
  • chemical and petrochemical streams,
  • heavy industry,
  • molasses, vinasse, and viscous sugar streams.

Technical Selection Data

Key parameters:

  • exchange area: 1–500 m²,
  • connections: DN25–DN300,
  • operating pressure: up to 10 bar, with higher pressures upon design,
  • operating temperature: -20 °C to 200 °C,
  • media: liquids, steam, and gases.

Materials and Configurations

Spiral and shell materials include P355GH, AISI 304, AISI 316L, and AISI 904L. Gaskets are available in NBR, EPDM, PTFE, or graphite. Channels can be with spacers or Free Flow without spacers for media with solids and fibers. Construction can be openable for mechanical cleaning or welded for clean fluids.

Standards

Design covers EN 13445, PED 2014/68/EU, and ASME Section VIII Div. 1. Connections can be customized to known industrial standards per project.

FAQ

When is a spiral heat exchanger selected?
When the fluid easily clogs or fouls conventional exchangers.

When is an openable version needed?
When frequent inspection or mechanical cleaning is anticipated.

What data is required for sizing?
Flow rates, temperatures, pressure, viscosity, solids, allowable pressure drop, and cleaning schedule.

Description

Exceptionally well-suited for sludges, slurries, waste water, fouling, liquids with high viscosity, and liquids that contain fibers and solids, our SONDEX® spiral heat exchangers are the definitive solution for applications that require treatment of challenging fluids. The design allows for a countercurrent flow that makes it possible to achieve very close temperature approaches.

Since we use coiled metal sheets instead of tube bundles, we can achieve very high thermal performance without sacrificing the channel gap that lets the media flow unimpeded.

The spiral coil itself also contributes to the turbulent flow, and the single-channel design helps alleviate fouling with a “self-cleaning” effect. Accumulated deposits create local increases in velocity, creating a scrubbing effect that is enough to loosen the build-up in fouling in most cases. This allows our SONDEX® spiral heat exchangers to operate in very long sessions without maintenance or cleaning.

Some media, however, are so challenging that the heat exchanger requires more frequent maintenance and cleaning. With this in mind, we have designed hinged covers that are sealed with C-clamps, creating a swing door that is very easy to open and close without any special tools required, letting you access the entire coil for inspection and cleaning.

Features and benefits

  • Exceptionally well-suited for sludges, slurries, waste water, fouling, liquids with high viscosity, and liquids that contain fibers and solids, our SONDEX® spiral heat exchangers are the definitive solution for applications that require treatment of challenging fluids. The design allows for a countercurrent flow that makes it possible to achieve very close temperature approaches. Since we use coiled metal sheets instead of tube bundles, we can achieve very high thermal performance without sacrificing the channel gap that lets the media flow unimpeded. The spiral coil itself also contributes to the turbulent flow, and the single-channel design helps alleviate fouling with a “self-cleaning” effect. Accumulated deposits create local increases in velocity, creating a scrubbing effect that is enough to loosen the build-up in fouling in most cases. This allows our SONDEX® spiral heat exchangers to operate in very long sessions without maintenance or cleaning. Some media, however, are so challenging that the heat exchanger requires more frequent maintenance and cleaning. With this in mind, we have designed hinged covers that are sealed with C-clamps, creating a swing door that is very easy to open and close without any special tools required, letting you access the entire coil for inspection and cleaning.
  • The channel size is selected to fit the flow and qualities of the media. The many variations in diameters and widths of the spiral coil allow for many different combinations, which mean that we can create the optimal solution for every duty.
  • Designed to handle a very aggressive temperature program and with a wide range of materials and plate thicknesses available, we customize each spiral heat exchanger to match the requirements of any application.
  • Limited need for maintenance and cleaning ensures extended operational uptime. If the need for cleaning arises due to particularly difficult media, the hinged covers provide easy access to the entire heat transfer surface.
  • Very compact solutions, our spiral heat exchangers have minimal space requirements. Despite their small stature, the long, curved flow paths allow for very high heat transfer coefficients up to twice as high as their shell and tube counterparts.

Applications

  • Dairy/food/beverage industry
  • Biogas industry
  • Wastewater industry
  • Pulp and paper industry
  • Heavy industry
  • Petrochemical industry
  • Chemical industry

Technical specifications

  • Connections from DN32 to DN300 (1 1/4" to 12")
  • (Frames designed according to FEA and PED 2014/68/EU (EN13445) and ASME sec VIII, Div. 1 construction standards)
  • Shell materials: Carbon steel, stainless steel
  • Spiral materials: Carbon steel, stainless steel
  • Working pressure up to 16 bar (145 psi)*
  • Working temperatures from -20 °C to 200 °C (-4 °F to 392 °F)

*Higher pressure available upon request