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Silica Scale Removal from Cooling Water System

Does anyone know commercially effective method of removing silica scale from cooling water lines and cooling equipments? The methods available should not include the use of hazardous materials such as hydrofluoric acid and/or fluoride compounds.I would appreciate if anyone give me any suggestions.

Hiromi Kawaguchi
- Tokyo, Japan
2000

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Hiromi,

Depending on the size of the scale and it's settling rate, a Hydro-cyclone may be the least expensive option, from an operations and capital cost standpoint, than either filtration or chemical precipitation, as a solution to the problem.

Neil E. Hatfield
- Franklin Park, Il. USA
2000

Silica removal from the source water is possible with an activated alumina system. Once its scaled onto the system piping and surfaces, its too late for anything but acid washes or replacement.

Kyle D. Carr
- Los Alamos, New Mexico, USA
2001

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Hi,

Possibly the unique form for to remove silica hard-deposit is by using appropriate inorganic acids. . . . but do not be frightened about it. Remember the "poison" is not in the poison itself, but the amount of it. I suggest that you contact a Professional Chemical-Cleaning Contractor. You can, then, be in good hands.

Mr. J. Barreda
- Nuevo Leon, Mexico
2002

Numerous acid descalers in liquid and powder form are available depending on the type of metal you are working with, some have internal pH indicators to determine when the solution is weak. Use of these will remove the binder attaching the silica to the substrate as a temporary fix, for a long term solution to redeposition use either mechanical filtration or a chemical dispersancy method available through most of the water treatment companies.

Randal Argabrite
- Fostoria, Ohio, USA
2003