Caravan Water Filters

\'Water, water everywhere, but none to drink\' was the war cry in a local ecologists\' demonstration in my city a week ago. Truly, three fourths of earth is water, but this water is containing too much dissolved sodium chloride to be worth drinking directly. Even with the fresh, sodium chloride free water that is available to us, the contaminant content in them is quite high. The degree of chemical and physical treatments that it takes to produce potable water makes it an expensive commodity.

One of the most commonly used methods for the same is filtration. Water filters in one or the other design can be seen everywhere – in homes, in offices, in shopping malls, even in mobile caravans and with campers seen lying in nature\'s lap.

Most of the water filters have a charcoal or activated carbon filtration unit – it is prepared from coconut husk or lignite or peat deposits. Activated carbon is made porous by special treatment in the lab – this increases its absorption powers manifold. The water to be purified is allowed to trickle down the carbon filtration unit. Being of a porous nature, activated carbon traps the visible dust particles and the substances causing water to be coloured and malodorous thereby making water free of the bulk of its impurities.

These filters, however, are incapable of ridding water of its germ load. Nano silver comes to the aid here – it is capable of bactericidal action, and hence aids charcoal filters in reducing the microbial content of the water. Another method is the use of ultraviolet rays – they are also capable of killing microbes and hence, UV treated water is considered safe from pathogens.

Now, even this is not enough. Water can contain suspended as well as dissolved impurities and charcoal takes care only of suspended ones. For the removal of dissolved impurities, another sophisticated method called reverse osmosis is used. Reverse osmosis water filters utilise high pressure – in the range of 400-650 psi in order to force dissolved impurities out of it.

Simple household water filters may or may not utilise ultraviolet and reverse osmosis – the cost of the filtration unit may shoot up owing to it. Hence, it is the usual carbon or charcoal filters that come to their aid. Household water filters are mostly tabletop appliances but they may also come as kitchen tap attachments or wall-hanging apparatuses.

One variation of the usual water filter is the very-popular-in-America model of fridge water filters. These contain a filtration unit attached externally or internally to the refrigerator. The external attachment has enjoyed greater popularity owing the ease of replacement of its cartridges – internal attachment filters are dogged by the hassle of cartridge replacement. Major companies that have a hand in the manufacture of fridge water filters are Amana, Samsung, Beko, LG, GE, Siemens, Atag, Kenmore, Maytag Culligan and Whirlpool.

Also popular are portable water filters, known better as the caravan water filters. They are ideal for caravan owners and frequent campers for whom the source of water they use is almost never the municipality cleaned water used by the city dwellers. These caravan water filters have flexible pipe fittings so that they may purify water from the sources like springs, mountain lakes, wells, hand pumps or sundry faucets. They deodorize and decolourize water and thus increase water drinkability.

Usually, filter cartridges need to be replaced or cleaned after regular intervals – since they are involved in filtration, it is likely their pores can get clogged by the dirt they trap. This is especially true of the charcoal filters – they require replacement or cleaning after every six to nine months. If their clogged pores are left untreated, the organic waste trapped there tends to rot and emit foul smells.

Replacement cartridges are also easily available in the markets today. Most of the standard manufacturing companies that produce the filters also make the replacement cartridges suitable for their individual models.

One more thing to be kept in mind is the size of the filter pore. The size is measured in microns – this is called as micron size rating. The smaller the size, the smaller sized suspended particle it can remove. For instance, 0.01 micron sized pore can help trap bacteria. Hence, it is required of the buyer to select a suitably sized filter.