If your falling film evaporator experiences regular tube fouling to the point where manual cleaning is necessary, the cause can be identified and eliminated.
What’s Behind Tube Fouling?
The main reason for tube fouling is poor liquid wetting, which results in dry spots. The product then cooks onto the surface and the blockage grows as more product tries to flow through the tube.
Common causes for poor liquid wetting include:
- Flawed liquid distribution design
- The distribution pan is not installed correctly
- Plugging of the holes in the distribution pan
- Spray balls are notorious for uneven liquid distribution
To determine which cause(s) are behind your evaporator tube fouling, Caloris recommends performing an evaporator assessment. This will detect the underlying issues and provide a path to correct the problems. Watch our archived webinar on Improving Evaporator Efficiency.
Specialty Testing for Precise Diagnosis
Caloris offers a specialty eddy current test (ECT) for determining the mechanical integrity of tubes after they have been cleaned of product deposits. Eddy current testing provides an analysis down the entire length of the tube, reaching places you can’t visually inspect.
The ECT measures the thickness of the metal. Where the metal is too thin, cracks and leaking can occur. The non-destructive technology uses electromagnetic induction to detect and characterize surface and sub-surface flaws in conductive metals. It is sensitive enough to detect the size of pits in the metal.
Caloris uses the ECT results to pinpoint problem areas in existing evaporators. Targeted fixes can then be applied, potentially saving operators expensive replacement costs.