self-cleaning shell and tube heat exchangers
This technology applies the circulation of solid particles through the tubes to remove fouling deposits from the tube wall.
Advantages
1. Unique self-cleaning potential for extremely severe fouling applications.
2. Retrofit of existing conventional exchangers into a configuration, which applies the KLAREN self-cleaning technology on an intermittent or continuous basis.
3. New exchangers can be designed in such a way that the KLAREN self-cleaning technology can be added a later stage if fouling proves to be more severe than originally anticipated.
The Retrofitting of Fouling Heat Exchangers
Into a Self-Cleaning Configuration
Dr. Ir. Ing. D.G. Klaren M.Sc.
Premise
Many exchangers, evaporators, and reboilers that are in severe fouling services can now be retrofitted into a self-cleaning heat exchanger.
Principle
New self-cleaning heat exchange technology has been developed by KLAREN BV that can be applied in most vertically oriented shell and tube exchangers. The fouling prone fluid, stream one in figure 1, that flows upward inside the tubes, is charged with solid particles that are swept upward with the fluid producing a scouring action on the walls of the tubes as they travel. A unique distribution system in the inlet channel provides a uniform distribution of liquid and particles into all the tubes. From the outlet channel the particles are carried to the separator where they disengage from the liquid and are returned through the external down comer into the control channel and from there through the connecting line between control channel and inlet channel into the inlet channel. The flow of particles is activated by the control liquid flow, which is a fraction of the total liquid flow supplied to the exchanger. By changing the control liquid flow, the intensity of the cleaning action can be varied. If desired the cleaning can also be applied intermittently.
For more information please see:
www.KlarenBV.com
Fig 1: Principle of self-cleaning heat exchanger with KLAREN separator.
Applications
1. Forced circulation evaporators and reboilers.
2. Chemical processes were heating or cooling causes polymerization fouling, or resinous deposits.
3. Heat recovery from fouling wastewaters.
4. Process cooling with hard scaling and/or biologically fouled water
5. White water and black liquor heating in the pulp and paper industry.
6. Raw juice heating in the food processing industry.
7. Heating of geothermal brines.
8. Brackish and seawater desalination.
9. Temperature controlled cell disruption in the biotech industry.
Typical retrofit applications:
- Forced circulation reboilers (Thermosyphon reboilers would have to be converted to forced circulation type reboilers for retrofitting)
- Forced circulation evaporators
- Long tube vertical evaporators
- Short tube vertical evaporators
- Heating applications that foul
- Cooling applications that operate near the melting point of one of the chemical components in a mixture