Drinking Water Treatment for Homes and commercial use./معالجة مياه الشرب للاستعمال المنزلى والتجارى

Drinking Water Treatment for Homes and commercial use.
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The goal of water treatment is to reduce or remove all contaminants that are present in the water. No water, irrespective of the original source, should be assumed to be completely free of contaminants.

The most common process used for treatment of surface water and ground water consists of sedimentation, coagulation, filtration, disinfection, conditioning, softening, fluoridation, removal of tastes and odors, corrosion control, algae control, and aeration.

Sedimentation allows any coarse particles to settle out. Coagulation consists of forming flocculent particles in a liquid by adding a chemical such as alum; these particles then settle to the bottom. Filtration, as the name implies, is the passing of the water through a porous media; the amount of removal is a function of the filtering media.

Disinfection kills most harmful organisms and pathogenic bacteria—chlorine is the most commonly used disinfecting agent. Softening means removal of materials that cause "hardness," such as calcium and magnesium. Corrosion is an electrochemical reaction in which metal deteriorates when it comes in contact with air, water, or soil.

Drinking Water Treatment for Homes and commercial use.

In a typical municipal water treatment process, water flows through pumps to a rapid mix basin, then to a flocculation basin, to a settling basin, through filters to a clear well, then after disinfection, to storage tanks, and finally to the end users.
In areas that derive their water from rivers, pumps must be used since rivers are usually in low areas.

Water enters the treatment plant at what is called the rapid-mix basin, where aluminum sulfate, polyelectrolytes, polymers, or lime and furic chloride are added as coagulants. The water flows next to the flocculation basins, where the coagulant mixes with the suspended solids.

The coagulant is used to form suspended solids into clumps, or floc, which then settle out of the water. Floc forms when the particles from small solids gather to form larger particles. The water then slowly flows through settling basins where the floc settles from the water

. Activated carbon is then added to the water to remove color, radioactivity, taste, and odor. Filtration then removes bacteria and turbidity from the water as it removes any remaining suspended solids and the activated carbon.

The water then enters a clear well, where additional chlorine is added to kill any pathogens which may be present. A minimum free-chlorine residual of at least 0.2 ppm is recommended in plants requiring sanitary protection through the whole water distribution system. In water supplies that are fluoridated, 1 milligram per liter of fluoride is added.

At this stage in the process, the water is potable, palatable, and ready for consumption. The water is moved into elevated tanks for storage through pumps. The water flows down from these tanks into the community.

Raw water and post-treatment water are tested for bacterial, physical, and chemical standards, particularly pH, color, and turbidity. The Safe Drinking Water Act of 1974 established maximum contaminant levels, which are the national drinking water standards. These apply to any water distribution system that serves at least twenty-five units daily. Standards may vary from state to state, but they cannot be lower than those prescribed by the federal government.

Many water quality problems can now be treated in the home with water filters, distillers, softeners, reverse osmosis units, and chemical units. Being an educated consumer will help you choose a home treatment system for your specific water quality problems and allow you to interact knowledgeably with salespeople and water treatment specialists.

If more than one water quality problem exists, choosing a treatment device can be especially confusing and complicated. Many times you cannot treat one problem without treating another first. Sometimes, two problems can be eliminated with one treatment. And, occasionally the treatment itself causes other problems.

For example, it is impractical to install a distiller to remove lead from your drinking water if your water is corrosive and continues to remove lead from the housepiping system. Similarly, a reverse osmosis unit installed to remove a pesticide contaminant will not work efficiency if the water also contains particles of insoluble minerals which can clog the membrane filter.

Depending on your source of water, you may have to correct minor problems before you can address your concern. The following guidelines for water treatment are based on the fact that it is practical and efficient to treat some water quality problems before others. For instance, only after turbidity, acidity, hardness and iron have been controlled will activated carbon filters, reverse osmosis units, or distillers operate efficiency.

Remember, these steps are a simplification of water treatment. When considering home water treatment, consult with water treatment professionals at a reputable and certified dealership to determine the best treatment approach for your particular problem.
Drinking Water Treatment for Homes and commercial use.

Water Treatment Steps
1. Have water tested for contaminants.
2. Remove fine sand, silt, clay and other particles, using a mechanical filter or sedimentation.
3. Treat bacterial contamination, using chlorination or other forms of disinfection.
4. Remove hydrogen sulfide gas and other odor-causing substances, using chlorination, an oxidizing filter, or activated carbon.
5. Remove insoluble iron and manganese particles using:
o a mechanical filter
o a water softener, for small amounts of dissolved iron and manganese
o an oxidizing filter for higher amounts of dissolved iron and manganese
o a chlorinator followed by a mechanical filter or an activated carbon filter for very high amounts of dissolved iron and manganese.
6. Treat for hardness using a water softener.
7. Neutralize acidity using a neutralizing filter.
8. Remove volatile organic chemicals, trihalomethanes, certain pesticides and radon, using an activated carbon filter.
9. Remove heavy metals, such as lead, mercury, arsenic, or cadmium, with reverse osmosis units or a distiller.