Unique Pollution Control

Flocculation

WE PROCESS THE CHEMICAL TREATMENT

Flocculation, in the field of chemistry, is a process wherein colloids come out of suspension in the form of floc or flake; either spontaneously or due to the addition of a clarifying agent. The action differs from precipitation in that, prior to flocculation, colloids are merely suspended in a liquid and not actually dissolved in a solution. In the flocculated system, there is no formation of a cake, since all the flocs are in the suspension.

During the flocculation stage, the heavy, dense floc settles to the bottom of the water in large tanks. As you can imagine, this can be a slow process! Once the floc settles, the water is ready for the next stage of treatment.

Clarification

Clarification occurs in a large basin where water is again allowed to flow very slowly. Sludge, a residue of solids and water, accumulates at the basin's bottom and is pumped or scraped out for eventual disposal. Clarification is also sometimes called sedimentation.

Softening and Stabilization

When water is too "hard" (i.e. contains too much calcium, magnesium or other minerals), it forms scale and causes a variety of problems in pipes. Hard water can also result in laundering and washing problems, because it reduces the effectiveness of soaps and detergents.

Conversely, when too many of these minerals are removed, water can become too "soft". Soft water can cause corrosion in pipes.

Drinking water plants attempt to maintain a desirable balance between hardness and softness. This is accomplished by adding minerals to soft water and removing them from hard water. (Measure hardness as CaCO3 with a Hach titration procedure based on the USEPA-approved method.)

Filtration

Filtration will play the major role in this process :

Turbidity is a physical characteristic that makes water appear cloudy when suspended matter is present. The filtration process removes suspended matter, which can consist of floc, microorganisms (including protozoan cysts such as Giardia and Cyrptosporidium), algae, silt, iron, and manganese precipitates from ground-water sources, as well as precipitants which remain after the softening process. 

These suspended materials are filtered out when water passes through beds of granular material, usually composed of layers of sand, gravel, coal, garnet, or related substances. (Measure turbidity with a Hach turbidimeter.)

Fluoridation & Disinfection

Fluoride (F-) is added to water to reduce tooth decay. Fluoridation is an effective, economical process endorsed by many public health groups worldwide. Fluoride is fed into the water system as either a dry powder or in solution. (A Hach fluoride test detects fluoride levels in the water.)

During disinfection, disease-causing organisms are destroyed or disabled. Chlorine (Cl2) is the most common disinfectant used in the United States because it is practical, effective and economical.

Because chlorine dissipates rapidly, it is important to add the right amount of chlorine at the water treatment plant to make sure disinfection continues while the water is flowing through the distribution system. (Use a USEPA-approved Hach method to measure chlorine in water.)

Holding Tanks

Finished water (the term water treatment professionals use) is stored in holding tanks. The tanks provide a water reserve to meet the changing water demands of the communities they serve.