Flowing Towards Purity: Mastering the Art of Water Treatment

How to properly treat water

Water is life; this truth is unanimously admitted. In order for it to perform this main function, it must be clean and healthy, in a clean environment. For this, it must follow a specific treatment process. Equipment may vary but the basic principles of water treatment are similar.

Pretreatment

This phase consists of eliminating as much waste as possible. It happens that the waters are very heavy. Specialized companies use ozone oxidation. This operation aims to:

• remove metals from water
• reduce tastes, odors and colors
• optimize future treatments
• coagulation / flocculation

During coagulation, liquid aluminum sulfate and/or a polymer are added to the water which is in its initial state. When mixed with water, small dirt particles in the water stick or coagulate and form larger, heavier particles called flocs. They are easier to eliminate by decantation or filtration. It should be noted that these particles influence the color of the water.

Sedimentation

As water and floc particles progress through the treatment process, they move into sedimentation basins. As water moves, it forms particles that collect at the bottom in the form of mud. This is transported to the dry lagoons. In direct filtration, the sedimentation step is not included and the floc is removed only by filtration. During sedimentation, waste management professionals exploit the law of gravity.

Filtration

The water passes through a filter designed to remove particles present in it. The filters are made of layers of sand and gravel and, in some cases, crushed anthracite. Filtration is a process which is based on collecting impurities and dirt suspended in water. It improves the effectiveness of disinfection. The filters are regularly cleaned by backwashing. The filters used are the brush filter or the membrane filtration technique.

Disinfection

Water is disinfected before entering the distribution system to ensure the destruction of disease-causing bacteria, viruses and parasites. Chlorine is generally used because it is a very effective disinfectant. Residual concentrations can be maintained to prevent possible biological contamination in the water distribution system.

Fluoridation

Water fluoridation involves treating water supplies in communities. This allows the concentration of free fluoride ion to be adjusted to the optimal level. Indeed, the presence of fluoride makes it possible, for example, to reduce dental caries. During this fluoridation process, care must be taken to maintain a perfect balance because excess fluoride leads to the destruction of the enamel which in turn causes dental malformations, digestive disorders, etc.

pH correction

To adjust pH levels, lime is combined with filtered water. This also stabilizes naturally soft water to minimize corrosion in the water distribution system and customer plumbing. In any case, after the water treatment process, it should not taste like baking soda

Refining

As its name suggests, this operation aims to improve water quality. For this certain processes are commonly used such as:

• absorption using activated carbon: it has the ability to fix organic components which could not be detected during previous operations
• stripping: it is a method of water treatment aimed at reducing as much as possible the quantity of gases dissolved in the water