Electro-Flocculation Mechanism of Physical Water Treatment for the Mitigation of Mineral Fouling in Heat Exchangers

• Published in: Experimental heat transfer 2007-10, Vol.20 (4), p.323-335
• Main Authors: Cho, Y. I., Kim, W. T., Cho, D. J.
• Format: Article
• Language: English
• Subjects: Applied sciences; bulk precipitation; Devices using thermal energy; Energy; Energy. Thermal use of fuels; Exact sciences and technology; fouling mitigation; Heat exchangers (included heat transformers, condensers, cooling towers); particle count; PWT
• ISSN: 0891-6152; 1521-0480
• DOI: 10.1080/08916150701418302

The objective of the present study was to investigate the mechanism of a physical water treatment (PWT) technology used to mitigate mineral fouling in a heat exchanger. The PWT method tested utilized a solenoid coil to produce induced electric fields in a feed pipe prior to the heat exchanger. Fouling experiments were conducted using well water circulated through a laboratory cooling tower over 270 h with no blowdown, and fouling resistances were determined over time. Compared with the fouling resistance for the baseline case, those obtained with the PWT technology showed high efficacy for maintaining a low fouling resistance value. Samples of circulating well water were collected and analyzed using a laser particle counter over time. After 4 days of operation, the total number of particles was approximately 1 million per cc for the untreated case, whereas the case with PWT produced 3.5 million per cc. The present data on the particle counting provide empirical support for the bulk-precipitation hypothesis for the mechanism of PWT generally and electro-flocculation mechanism for solenoid coil techniques in particular.