Monday, July 13, 2009


A modern day kitchen is not complete unless there is a water purification system installed for continuous supply of safe water because people's trust and confidence on the ability of the civic authorities to supply safe water to their houses are at an all time low. As mentioned in an earlier post in this blog, unsafe water in India has spawned a whole gamut of business for the industry that makes bottled drinking water and an array of equipment for water clean up, the most preferred being the reverse osmosis system using selective membranes to remove minerals and microorganisms. Process water for commercial processing and bulk supply is made using large scale systems involving filtration, decolorization, deodorization, ion exchange treatment and disinfection. Current WHO guidelines for safe water lay down upper limits of many minerals, insecticide residues and other parameters.

With country's surface water sources not being able to supply adequate water to the burgeoning population in the urban settlements, ground water is being extracted in large scale all over the country by going down to as much as 500 ft below the surface of the earth. The chemical, physical and microbiological quality of water from underground vary enormously and they are often found to be high in hardness Hard water, though not unsafe by itself, is not liked because of its taste and the tendency to form hard scales inside the supply lines, corrode taps, reduce the cleaning capacity of detergents, take longer time for cooking and cause stains on utensils, containers, walls and flooring. In many towns and cities, houses in the main areas are supplied with 'treated' water while those in suburban and extensions get bore well water with varying degree of hardness.

It is beyond the capacity of an ordinary family to invest individually in large treatment systems that can ensure clean water for all the house hold activities though for drinking purpose small purification gadgets are installed. Are these citizens left with no choice but to depend on hard water for their sustenance? Probably there is some hope if the claims by two innovative technologies, using no power for water treatment, are true. Water can be categorized based on its hardness scale into very soft water (0-70 ppm hardness), soft water (70-140 ppm), slightly hard(140-210 ppm), moderately hard (210-320 ppm), hard (320-530 ppm) and very hard (>530 ppm). Hardness in water is due to presence of mineral salts, carbonates, sulfates and chlorides, especially that of calcium and magnesium which get precipitated inside the pipes and appliances like geysers, washing machines, dish washers etc reducing their life in the process.

In one of the technologies an alloy of about 12 noble and semi-noble metals is used in a housing over which water flows and according to the theory electrons are 'added' to the water, completing the missing electrons in the constituent elements of the minerals contained in the input water. The electro-physical changes in the minerals neutralize the scale producing properties of minerals such as silica, alumina and calcium sulfate and prevent their adhesion to pipes and equipment. The minerals, though still present in the out put water flow through without causing any scale build up. It is claimed that this technology is in use in over 30 countries across the world, working satisfactorily in house holds, hotels, factories, industries, farms, nurseries, municipalities etc. Weak electric fields through which water is passed, in conjunction with venturic effects stemming from unique configuration of the core alloy prevent adhesion and cohesion of the water borne mineral particles. The flow rate must be about 1-3 meter per second and the device has to be grounded. At Rs 15-20 thousand rupees for a 1 inch pipe unit, the system deserves consideration.

The second technology on spotlight is magnetic purifiers where water is passed through or over a magnet having high level of energy and a reduction in pH level increases the Carbonic acid formation through break down of calcium bi carbonate. The de-scaling is initiated and argonite, a soft hydrated version of calcite is formed which is in a fine colloidal form to be flushed along with the flow. There is electromagnetic or electronic variant of the system. The cost for a small scale unit is estimated at about Rs 18000, considered reasonable as a one time investment. Both the technologies claim absolute freedom from regular maintenance and replacement of parts for a period of 10-20 years.

While these technologies are not India-specific, reasonable confidence can be placed on their claims but the problem lies in the manufacturers of these systems whose credentials are yet to be established. There is some scope to bring down the cost to less than Rs 10000 if organized mass production materializes due to consumer confidence on the system. Probably a government agency like National Environmental Engineering Institute at Nagpur could give the potential users the required assurance regarding their feasibility under Indian conditions.


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