Magnetic water treatment

Magnetic water treatment (also known as anti-scale magnetic treatment or AMT) is a method of supposedly reducing the effects of hard water by passing it through a magnetic field as a non-chemical alternative to water softening. Magnetic water treatment is regarded as unproven and unscientific.

General arrangement of MWT apparatus

Effectiveness

Vendors of magnetic water treatment devices frequently use pictures and testimonials to support their claims, but omit quantitative detail and well-controlled studies.[1] Advertisements and promotions generally omit system variables, such as corrosion or system mass balance analyticals, as well as measurements of post-treatment water such as concentration of hardness ions or the distribution, structure, and morphology of suspended particles.[1][2][3][4][5]

Hypothesized mechanisms
Main articles: Water and Magnetohydrodynamics

Duration of exposure and field strength, gradient, rate of change, and orientation along or perpendicular to flow are variously cited as important to the results.[6] Magnetic water treatment proponent Klaus Kronenberg proposed that the shapes of solute lime molecules are modified by strong magnetic fields, leading them to precipitate as spherical or round crystals rather than deposit as sheets or platelets of hard crystals.[7] Simon Parsons of the School of Water Sciences at Cranfield University proposed that the magnetic field reduces the surface charge on small particles, increasing the tendency to coagulate as large particles that stay with the flow rather than depositing as scale. However, an internal study in 1996 at Lawrence Livermore National Laboratory found no difference in preferred crystal structure of scale deposited in magnetic water treatment systems.[8]

Liu et al.[9] and Coey and Cass published research in 2010 and 2000 reporting that magnetic treatment causes water containing minerals to favor formation of a more soluble form of calcium carbonate (aragonite rather than calcite).[10]

Pipe material

The effect of magnetic treatment depends on properties of the pipe. The magnititude of the effect depends on pipe conductivity and surface roughness.[11]

There are related non-chemical devices based on a variety of physical phenomena which have been marketed for over 50 years with similar claims of scale inhibition.[12] Whilst some are effective, such as electrolytic devices,[13][14][15][16] most do not work.[1]

Other uses of magnetic devices:

See also

References
  1. Keister, T (2008). "Non Chemical Devices: Thirty Years of Myth Busting" (PDF). Water Conditioning & Purification. Archived from the original (PDF) on 17 April 2012. Retrieved 11 December 2009.
  2. Powell, MR (1998). "Magnetic Water and Fuel Treatment: Myth, Magic, or Mainstream Science?". Skeptical Inquirer. 22 (1). Archived from the original on 27 July 2009. Retrieved 26 October 2007.
  3. Lower, S. "Magnetic water treatment and pseudoscience". Chem1Ware Systems Limited. Archived from the original on 1 May 2008. Retrieved 25 October 2009.
  4. Limpert, GJC; Raber, JL (1985). "Tests of nonchemical scale control devices in a once-through system". Materials Performance. 24 (10): 40–45. OSTI 6089699.
  5. Smothers, KW; Curtiss, CD; Gard, BT; Strauss, RH; Hock, VF (15 June 2001). "Magnetic Water Treatment" (PDF). Public Works Technical Bulletin 420-49-34. U.S. Army Corps of Engineers. Archived from the original (PDF) on 15 December 2011.
  6. Chaplin, M. (26 July 2011). "Descaling of Water". Water Structure and Science. London South Bank University. Archived from the original on 27 May 2012. Retrieved 26 March 2012.
  7. "Interview of Klaus Kronenberg, Ph. D". GMX International. Archived from the original on 22 February 2012. Retrieved 26 March 2012.
  8. Krauter, PW; Harrar, JE; Orloff, SP; Bahowick, SM (1996). "Test of a Magnetic Device for Amelioration of Scale Formation at Treatment Facility D" (PDF). Internal Report. Lawrence Livermore National Laboratory. doi:10.2172/567404. OSTI 567404. Retrieved 11 December 2009.
  9. Liu, C. Z.; Lin, C. H.; Yeh, M. S.; Chao, Y. M.; Shen, P (2010). "Surface Modification and Planar Defects of Calcium Carbonates by Magnetic Water Treatment". Nanoscale Research Letters. 5 (12): 1982–1991. Bibcode:2010NRL.....5.1982L. doi:10.1007/s11671-010-9736-5. PMC 2991221. PMID 21170405.
  10. Coey, JMD; Cass, S (2000). "Magnetic water treatment" (PDF). Journal of Magnetism and Magnetic Materials. 209 (1–3): 71–74. Bibcode:2000JMMM..209...71C. doi:10.1016/S0304-8853(99)00648-4.
  11. Alimi, F.; Tlili, M. M.; Amor, M. B.; Maurin, G.; Gabrielli, C. (2009). "Effect of magnetic water treatment on calcium carbonate precipitation: Influence of the pipe material". Chemical Engineering and Processing: Process Intensification. 48 (8): 1327. doi:10.1016/j.cep.2009.06.008.
  12. "Chlorine Dioxide Water Treatment & Water Disinfection". Watertreatmentservices.co.uk. Retrieved 13 November 2016.
  13. Coetzee PP, Yacoby M and Howall S (1996) The role of zinc in magnetic and other physical water treatment methods for the prevention of scale. Water SA, 22(4): 319-326.
  14. López-Sandoval E, Vázquez- López C, Zendejas- Leal BE, Ramos G, San Martín-Martínez E, Muñoz Aguirre N, Reguera E (2007) Calcium carbonate scale inhibition using the "allotropic cell" device. Desalination 217:85-92.
  15. Pernot B, Euvrard H, Remy F and Simon, P (1999) Influence of Zn(II) on the crystallisation of calcium carbonate application to scaling mechanisms. Journal of Water SRT-Aqua, 48(1): 16-23.
  16. MacAdam J PhD Thesis Cranfield University UK. Dept of Water Science and various studies
  17. Whitaker, S (5 August 2011). "Guardian launches electrolytic scale inhibitor". Industry Today. Retrieved 24 February 2012.
  18. Watt, DL; Rosenfelder, C; Sutton, CD (1993). "The effect of oral irrigation with a magnetic water treatment device on plaque and calculus". Journal of Clinical Periodontology. 20 (5): 314–7. doi:10.1111/j.1600-051X.1993.tb00366.x. PMID 8501270.
  19. Johnson, KE; Sanders, JJ; Gellin, RG; Palesch, YY (1998). "The effectiveness of a magnetized water oral irrigator (Hydro Floss) on plaque, calculus and gingival health". Journal of Clinical Periodontology. 25 (4): 316–21. doi:10.1111/j.1600-051X.1998.tb02447.x. PMID 9565283.
  20. Allen, M (25 August 2010). "Looking For A Miracle: We Test Automotive 'Fuel Savers'". Popular Mechanics. Retrieved 26 March 2012.

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