Dirty muddy water is caused by dirt and mud in suspension in the water. To remove these suspended solids in water like dirt, fine sand, etc; we use sediment filters. Most of the domestic water filters to remove cloudiness from water are made of plastic and inside these plastic filter housing is the actual filter element, called a filter cartridge which removes the turbidity or cloudiness from water. Cartridges over the period gets clogged when it captures the dirt from the water and so water filter cartridges must be replaced at regular intervals, otherwise the flow through the water filter gets blocked.

In Pre Filter most common cartridge size is 2.5 inches in diameter and 10 inches in length with 5 microns porosity. PP (Spun Polypropylene) cartridges are the preferred cartridges since they last longer and also because they are more reliable in filtering to the desired sizes. Other cartridge filters like the Yarn cartridges cannot guarantee filtration to a particular particle size but it's service life is more. Within the Purifier Cabinet, Inline Sediment Filter used consists of 1.75 inches Diameter & 8 inches length.

Passing water through an activated carbon water filter purifier improves the taste of drinking water and also makes water safe to drink by removing Odour, Colour, Chlorine, Organic Impurities & Few Pesticides. So activated carbon is a very efficient purifier of water and is widely used in water filter purifiers.

Activated carbon is an extremely porous material that attracts and holds on its surface harmful chemicals by a process known as adsorption.

Activated carbon in water filter purifiers has a limited ability to adsorb contaminants from water, and so the activated carbon in water filters should be changed when it has been depleted and cannot purify water anymore. The pore structure of the activated carbon gets filled or saturated with the adsorbed pollutants and it cannot adsorb any more. At this stage the activated carbon will start rejecting some of the previously adsorbed pollutants back into the water flowing over it. This is called 'breakthrough'. When this happens, the concentration of pollutants in the treated water will be higher than in the raw water being treated. The activated carbon filter cartridge must be replaced well before this happens.

Activated Carbon water filter purifier does not remove microbes and dissolved inorganic chemicals like Nitrates, Fluorides and hardness in water. One of the big disadvantage of activated carbon water filter is that it can be a breeding ground for micro-organisms on the surface of the activated carbon filter media, especially when there is no running water over the activated carbon in the water filter, like when it is not being used for a long time, some of the organic chemicals adsorbed by the activated carbon becomes the meal for these bacteria.

The surface area within the pores of Activated carbon is huge, one gram of activated carbon can have surface areas of 500 to 1500 meter square depending on the Classification of the Activated Carbon. The quality of Carbon is decided by its Iodine Value. We use 1000 to 1100 IV Silver Activated Carbon in our Purifiers.

We counter the bacterial growth on the surface of activated carbon by impregnating the activated carbon with nano-silver particles. Silver ion is a bactericide and will be helpful in preventing these bacterial growth. Ultra Violet (UV) after activated carbon filter is another way of preventing the germs growing on the activated carbon to pass through your drinking water.

Membranes are very thin sheets of a synthetic plastic material which have very fine holes or pores. The size of pores are different in different types of water purification membranes. The types of membranes used to purify water are classified according to the pore size of membranes as Micro-filtration membranes (MF), Ultra-filtration membranes (UF), Nano-filtration membranes (NF) and Reverse Osmosis (RO) membranes.

Microfiltration Membrane has average pore size of 0.1 microns. Microfiltration is good for removing water borne parasites like protozoa, Cryptosporidium and Giardia, but is not good for removal of bacteria and viruses. Microfiltration is mostly used in the food industry for processing fruit juices and milk products. Even it has great benefit to use as Pre filtration in high Turbidity River water or to protect NF or RO Membrane from turbidity in ground water.

The next higher pore size membrane is Ultrafiltration membrane which has a pore size average of 0.01 micron. UF membranes will not allow any bacteria, viruses, parasites or any microbe to pass through. Thus an ultra-filter membrane water purifier is very useful in situations where you have good water but have to guard yourself against germs. An ultra-filter water purifier is better than an UV water filter because an ultra-filter UF water purifier actually removes all germs and microbes from the drinking water using only normal tap water pressure.

Next is the Nanofiltration Membrane with a pore size at an average of 0.001 micron. Being only slightly larger than the RO pore (0.0001 microns) and also only very slightly larger than the size of the common salt (NaCl) molecule. So it allows monovalent common salt Sodium Chloride to pass through but will not allow divalent Calcium salts like Calcium Carbonate of diameter 0.0009 microns to pass through. Since Nanofiltration membrane removes hardness from water one of its most important applications is in water softening. Nanofiltration membranes are also very efficient to purify water of heavy metal salts like Arsenic, Lead, Cadmium and Mercury and at the same time it removes all germs and viruses from water.

Reverse Osmosis membranes have the smallest pore size of about 0.0001 microns. This is just slightly larger than the size of a water molecule but smaller than the size of a Sodium Chloride Molecule at 0.0007 micron. So Sodium Chloride and all salts are blocked and only pure water flows through the RO membrane. Thus one of the main applications of RO membranes is in seawater desalination, by which sea water is purified to get fresh drinking water. In domestic Water Purifiers RO technology is recommended at least above TDS level of 800 ppm.

A UV Sterilizer uses ultraviolet radiation from a UV lamp placed inside the water to irradiate the water around it and thus kills all germs in the water around the UV lamp. UV water purifier works by having Ultraviolet rays penetrate the cells of bacteria and viruses destroying their ability to reproduce. Without this ability, these organisms cannot multiply and eventually die. UV water purifiers have a simple but very effective process, with the UV water purifier light killing upto 99.99% of germs in water.

Following things are very important to understand before having UV Sterilization in our Purifier:-

- UV Chamber make should be of SS 304 or 316 grade i.e. in Stainless Steel only.

- Horizontal position increases its effect by 10% to 20% due to water passes through churning motion.

- Intensity of any tube light available in Market will reduce after certain period, hence it is recommended to replace UV lamp after every 3 to 4 years.

- To protect the UV lamp from direct contact with the water there is a quartz glass sleeve around the UV tube-light which protects it against water entry and consequent electric shorting. The quartz sleeve should be of the correct quality of glass to allow the glass to be transparent to short wave UVC light of 254 nanometres, the most effective UV light wavelength to kill germs in the water. The quartz glass sleeve protecting the UV lamp can get dirty and scaled up, and this will make the UV water purifier ineffective by blocking the UV rays. Hence it is crucial to clean Quartz Glass periodically.