To get rid of most harmful bacteria, it takes a few seconds. And at an extremely low operational costs ultraviolet can handle thousands, tens and hundreds of thousands of gallons of water. By the way, thanks to this safe method of cleaning the inhabitants of St. Petersburg has been enjoying since 2007, unlike other Russians drinking water. But here, do not relax. Once the water enters the water supply network, there are big water adventure. Through the old, sometimes rotten to the water pipe will be exposed to hazardous substances bacteria and viruses. Suffice it to recall, when an accident occurs or replacement of water pipes – the water from the tap for an hour passes smoothly from dark brown or black to transparent.
And that got into the pipe at their welding – no one knows. So anyway, tap water can not drink. And then the question arises of its purification and drinking water quality is entirely dependent on our choice. And that today the market offers for domestic use? At present, widely used various filters – Membrane and a coal-based. As a rule, they only clean water from chemical and mechanical contaminants.
Membrane filters. Membrane processes can be classified by size of delayed particles into the following types: microfiltration (MF), ultrafiltration (UF), nanofiltration (NF), reverse osmosis (RO). In going from microfiltration to reverse osmosis membrane pore size decreases and, consequently, the minimum amount of delayed particles. In this case, the smaller the membrane pore size, the more resistance it provides to the flow and the greater the pressure required for the filtering process.