Nanotechnology in purifying drinking water in the developing world

YOUNGWOOD, Pa. - Oct. 6, 2014 - PRLog -- .
Background
Currently, WHO/UNICEF estimates [1] almost 1 billion people in the developing world do not have access to safe drinking water. Moreover, about 2 million childhood deaths have been attributed to water-borne diseases. Conventional water treatment is unfeasible because of costs. Lacking municipal water supplies, the water is collected from rivers or lakes and stored in containers for later use which may also be contaminated. The most direct way of purification  is by boiling small quantities of water, but this requires a source of heat which, except for fire, is usually not available. Because it is not always convenient to build a fire, it is highly desirable to consider alternative low-cost methods for purifying water.
Unfortunately, there are no known low-cost alternatives to purifying water other than by boiling. However boiling has disadvantages because a source of heat is needed. One could envision focusing sunlight to boil small volumes of drinking water, but the purified water would only be available during daylight hours. If, however, portable electrical power is available, the water could be pumped through ceramic or resin filters [2] coated with silver NPs. NP stands for nanoparticle. Silver NPs are widely known to provide antimicrobial action by damaging the DNA of bacteria, but NPs that come off the filter and enter drinking water also damage human DNA, that if not repaired, may lead to cancer. Regardless, NP coated filters are unfeasible because electrical pumping power is usually not available. In contrast, UV disinfection [3] of drinking water occurs outside the body and avoids the danger of cancer posed by silver NPs, but is unfeasible as electrical power is generally not available and costly even if available.

The developing world needs an inexpensive way of purifying drinking water.

Proposal
QED induced UV radiation using nano-coated drinking bowls is proposed as the mechanism by which drinking water is purified inexpensively without electrical power. QED stands for quantum electrodynamics. QED induced purification is a consequence of QM that forbids the atoms in nano-coatings under TIR confinement to have the heat capacity to increase in temperature. QM stands for quantum mechanics and TIR for total internal reflection. See www.nanoqed.org, 2014

Discussion
Disinfection occurs as the body heat from the hands of the person holding the drinking bowl is transferred to the coating as shown in the thumbnail. Because of QM, the body heat cannot increase the temperature of the coating as its heat capacity vanishes under TIR. Instead, conservation proceeds by QED inducing the heat to be converted to EM radiation. EM stands for electromagnetic. The TIR confinement only occurs as heat flows into the coating, i.e., absent body heat there is no TIR confinement and UV radiation is not produced. The TIR wavelength λ of the EM radiation is,

λ = 2 n d

where, n and d are the refractive index and thickness of the coating.Since the optimum UV wavelength range [3] to destroy bacteria is between 250 and 270 nm, a zinc oxide coating having n = 2 requires d = 65 nm.

Guidelines for the UV intensity suggest the minimum dose at all points throughout the water in the drinking bowl water require 16 to 38 mW / cm2. For the 20 cm drinking bowl, the body heat is required to be about 5 to 10 W. This amount of heat is consistent with the sudden application of body temperature 37 C to the coating at 20 C having a time constant τ,

τ = ρ Cp / H A

where, ρ is the density, Cp the heat capacity, and A the area of the coating. H is the heat transfer coefficient between the hand and bowl. Unlike classical physics, QM requires Cp to vanish, and therefore the response of the coating to  hand temperature is instantaneous. Since QM further requires no temperature change in the coating, the body heat into the coating that tends to increase its temperature is spontaneously converted to UV radiation that disinfects the drinking water/..

Conclusion
The QM requirement of vanishing heat capacity in the nano-coating of drinking bowls allows body heat in the hands holding the bowl to be induced by QED to produce UV radiation therby offering an inexpensive solution to purifying drinking water in the developing world .

References
[1] WHO/UNICEF, Progress on Drinking Water and Sanitation: 2012 Update.2012.
[2] L. Mpenyana, et al., “Cost-Effective Filter Materials Coated with Silver Nanoparticles for the Removal of Pathogenic Bacteria in Groundwater,” Int J Environ Res Public Health. Jan 2012; 9(1): 244–271.
[3] Ultraviolet Disinfection, National drinking water clearinghouse fact sheet, Tech Brief