ED2000
THEORETICAL DISCUSSION

 

Heat Exchange Unit
with scale buildup
Problems With Scale
Scale remains a serious problem to all industries that heat water in their processes.  It is especially true in plate and frame heat exchangers.

Heat Exchange Unit
protected from scale
buildup by deposit control device

Scale can build up on heat exchange surfaces, valves and pipes.  The scale can significantly reduce the heat transfer efficiency, cause valves to stick, and clog pipes.  Problems caused by scale include:

  • Decreased energy efficiency
  • Decreased flow rate in pipes
  • Increased thermal resistance
  • Increased downtime for cleaning
  • Premature replacement of heat exchange plates
  • Oversized design to address scale resistance
Patented Technology
The ED2000 technology was developed and tested through a collaborative R&D effort with Drexel University in Philadelphia, PA.  The results of the R&D effort are:
  • Nine new patents filed
  • Perfected technology to assure consistency
  • Field tested with major manufacturers
  • Chemical-free, environmentally friendly technology

"Uncontrolled precipitation" as scale precipitates onto heat exchanger surfaces
How does ED2000 electronic deposit control technology work?
This electronic deposit control method is based on oscillating electrical field technology. The electronic deposit control technology uses a signal cable that is wrapped around a pipe. 
The cable is connected to an electronic unit that sends a complex, dynamic current with rapidly changing polarity to produce an extremely small time-varying magnetic field inside the pipe (the magnetic field is hundreds of times weaker than refrigerator magnets used in the kitchen).
 
The time-varying magnetic field produces an induced, oscillating electric field inside the pipe.  The phenomenon  is well-known as Faraday's law. The induced, oscillating electric field provides the necessary molecular agitation for scale prevention and removal.

"Controlled precipitation" converts dissolved mineral ions into insoluble crystals, thus preventing scale formation on heat exchanger surfaces
Controlled Precipitation
The key to the ED2000 technology and its success relates to understanding water chemistry and the dynamics of heat transfer equipment.  The ED2000 unit treats the water before it enters the heat transfer area.  The unit produces a solenoid-induced molecular agitation to precipitate dissolved mineral ions to large insoluble mineral crystals.  By this "controlled precipitation" the crystals suspend in the water and do not adhere to metal surfaces, inhibiting the formation of scale.
Scanning Electron Microscope Photographs taken with scale specimen from scaled tubes produced at a flow velocity of 0.78 m s-1 and a concentration of 10 mol m-3 (a) without electronic anti-fouling device and (b) with EAF device. Magnification = 1500.

Scale specimen for SEM was prepared with a utility knife by scraping small amounts of scales from the outlet region of each scaled tube. SEM photographs of scales produced without the EAF (electronic anti-fouling) device (a) revealed that CaCO3 scales were needle-shaped aragonite, whose dimensions were approximately 25 mm by 2 mm. Aragonite is a dangerous form of calcium carbonate scale, which is crystallized at a temperature above 308 K. It is sticky, dense, and difficult to remove. The long-needle shaped crystals confirm that the precipitation reaction occurred on the heat transfer surface without the EAF device.

n contrast, the scales produced with the EAF device (b) depicted a very different structure from the one produced without the EAF device. The scales produced with the EAF device were a cluster of small elliptic shape particles (e.g., 10 mm by 3 mm) with no particular orientation, suggesting that many fine particles were formed in bulk solution, attached to the heat transfer surface, and then grew in size through precipitation reaction. 


The SEM photographs support the hypothesis of the EAF technology, which is to convert dissolved mineral ions into crystals in a bulk solution, thus reducing both the diffusion of dissolved ions to the heat transfer surface and subsequent precipitation reaction on the heat transfer surface. As a result, the production of aragonite type calcium carbonate is prevented. Calcium carbonate crystals formed with the EAF device appeared to be loosely connected. In other words, the scales formed with the EAF device may be removed at a small flow velocity (e.g., 1 m s-1), whereas the scales formed without the EAF device may not be removed even at a large flow velocity (e.g., 5 m s-1).
When the ED2000 treats water or other fluids, several things happen.
  • The hydrogen bonds between water molecules are broken and more water molecules are freed to hydrate scale ions and colloidal particles.
  • The scale ions dissolved in the water are agitated, they collide, and form scale molecules that join together to form crystals.
  • The colloidal particles in the water receive an enhanced surface charge, possibly from the freed water molecules. The enhanced surface charge is great enough for the colloidal particles to repel each other and the sides of the equipment, and stay suspended in the fluid.

 ED2000 Features and Benefits