Water treatment plant is a site where water treatment process is conducted. The water treatment itself is a process to return water to its natural state or to make it suitable for applications. Therefore, it is required both before and after the application. The type of treatment is varying depending on the application and the condition of the water. For instance, treatment of black water is different to treatment of grey water.
The process of water treatment in a water treatment plant involves business, engineering, art and science at once. It includes various methods including physical, chemical, biological and mechanical methods. Just like in any kinds of technology, this treatment has science as the foundation. Meanwhile, the engineering is necessary to make sure the technology for treatment works as designed. And the art is responsible to design the appearance of application.
In business terms, there are various companies throughout the world offering various water treatment processes. For instance, there is a leading company that offers various products include product to produce the ultrapure water. This particular product uses combination of reverse osmosis filter and active charcoal membranes.
Among various processes of water treatment performed in a drinking water treatment process, the general wastewater treatment is the most common one. It is inherently a process that converts used water or wastewater into environmental acceptable water that can even be used to drink. Just like any treatments, this process involves the removal of bacteria, plants, solids, algae, organic compounds and inorganic compounds. Sediment and filtration are common methods used to remove solids. Meanwhile, in order to remove any harmful pollutants, bacteria digestion has to be performed.
Process at Water Treatment Plant
Despite of various treatment methods, the process to treat water is basically the same. It is started by withdrawing untreated water from underground aquifer or surface water supply. The water then flows or is being pumped to the central plant facility. Usually, larger municipalities utilize several sources and have several water treatment plants facilities.
- Water Pumping
The next phase is pumping the water under pressure and channeling it to distribution system that usually consists of pipes network that is interconnected with elevated storage or ground level. When the water is withdrawn from its source, steel bars are required to screen through it. It is important so any large objects can be prevented from entering the water treatment plant facility. Other screeners are also used like finer screens to remove any leaves. In the case of muddy or cloudy water, large basin is used for pre-sedimentation basin to any large silt particles and sands can settle out.
- Water Disinfecting
Since all surface waters may carry pathogenic microorganism, it has to be disinfected before being consumed by human. The sequence of the treatment process in a water treatment plant includes sedimentation, flocculation, filtration and coagulation. Coagulation for instance aims to eliminate any repulsive forces that are found between the particles and finally enable them to aggregate. During this process, there are chemical coagulants being added such as iron salts or aluminum which is necessary in neutralizing negative charge found on the surface of any particles. With rapid mixing, the added coagulants will be dispersed.
- Water Oxidizing
At the same time, there may be some chemicals that include powdered activated carbon. These chemicals work to absorb chemicals that cause odor and taste. They are also necessary to help oxidizing any inorganic contaminants.
After the coagulation process is completed, the next phase involves introducing the water into sedimentation basin. Usually, within 2 to 4 hours, all the floc particles will settle out.
This next phase in water treatment plant involves water being filtered using anthracite or sand with 0.02 inch of diameter.
- Lime Softening
As the name suggest, it is a process of adding lime during the rapid mixing process in order to precipitate the magnesium ions and also calcium.
This is a necessary process that aims to prevent any scale and corrosion formation. It is usually performed by adjusting the alkalinity or pH of the water through adding of scale inhibitors.
- Activated Carbon Absorption
Here is a particular process to remove any chemicals that can cause both odor and taste to the water. It also removes the synthetic organic contaminants.
This last process in water treatment plant involves the increase of concentration of fluoride until it reaches optimum level. It is important to prevent any dental cavities.
Until today, the number of water treatment plant has kept on growing. There are hundreds of plants across the world. Of hundreds of them, there are 11 biggest plants. The first biggest plant is Jean-R-Marcotte WWTP in Montreal, USA. The 2nd is Detroit Waste Water Treatment Plant in Detroit. The 3rd is Stickney Water Reclamation Plant in Chicago. The 4th is Dear Island WWTP in Boston. China with Stonecutters Island Sewage Treatment is Hong Kong is the 5th biggest plant. The 6th biggest plant is Autotonilco de Tula Plant in Mexico City. Seine Aval WWTP in Paris makes the 7th biggest plant while Gabal el Asfar WWTP in Cairo is the 9th biggest plant facility. The number 9, 10 and 11 are Hyperion Sewage Treatment Plant in Los Angeles, Northeast Ohio Regional Sewer in Northeast Ohio and Beckton Sewage Treatment Works in London.
Once being viewed as something that needs to be disposed of, wastewater is now seen as potential resources. It doesn’t only make usable water through water treatment process but there are also other potential materials inside the wastewater such as methane and phosphorus gas.
Currently, only big countries that have been professional operating big water treatment plant. But in the near future, developing countries are predicted to be the building and operating the same plant. In fact, some countries have been started to build water treatment plant that will be soon started to operate in a few years later. In countries with a lot of annual rain, this plant is a very useful and potential facility to make use of the used and surface water.