Waste water treatment is a necessary process to reduce contaminants in sewage or wastewater and then transform it into a liquid that can be discharged into the natural water cycle. It is important that wastewater is treated before it can enter the system, as untreated sewage can cause damage to pipes, septic tanks, and drinking wells. Water treatment plants process wastewater by removing all sediments, making it easier for water to flow through pipes and eventually water out into the natural water cycle.
Wastewater can contain many contaminants such as heavy metals, chemicals, bacteria, fungi, and parasites. The wastewater that is processed by water treatment plants is then stored in holding tanks until it can be discharged into the natural water cycle. During this time the water undergoes treatment, removing any unwanted organisms. This treatment process also kills viruses, bacteria, and protozoa, which are often present in human wastes and can cause serious health problems if ingested.
A sewage treatment plant is designed to treat wastewater for at least two to three years. If not treated properly, wastewater may become contaminated with bacteria and other microorganisms, causing illness and disease. These pathogens can then cause waterborne diseases such as cholera, typhoid fever, hepatitis, diarrhea, dysentery, and cholera.
Most of the wastewater that enters water treatment plants is treated with chlorine and other disinfectants. In order to make wastewater safe for use in water systems, it must be dechlorinated. Dechlorination is done using a process called deionization. The most common method used for deionization involves applying a chemical known as an activator. Activators are commonly found in various products such as detergents and cleaning agents.
When chlorine is added to the wastewater, it is typically combined with an activated carbon block or other media such as activated carbon, activated sludge, or carbon-based resins. The combination of these media works by binding the chlorine molecules to the larger molecules of the contaminants. The larger molecules of the contaminants then float to the bottom of the container, while the chlorine atoms stick to the smaller ones. This process makes it difficult for the small dissolved contaminants to interact with the large ions, which are responsible for breaking down the larger molecules.
In some cases, wastewater is treated with a combination of both chlorine and an activator. The combination of chemicals is called activated carbon granular carbon block technology. This technology is used in a few water treatment plants. Another common way to treat wastewater is through carbon filtration. Carbon filtration is also commonly used in desalination plants, but this method usually has a high cost associated with it.