What are the 5 stages of water treatment?
They typically consist of several steps in the treatment process. These include: (1) Collection ; (2) Screening and Straining ; (3) Chemical Addition ; (4) Coagulation and Flocculation ; (5) Sedimentation and Clarification ; (6) Filtration ; (7) Disinfection ; (8) Storage ; (9) and finally Distribution.
What is coagulation flocculation and sedimentation?
Coagulation-flocculation: The use of chemical reagents to destabilise and increase the size of the particles; mixing; increasing of flog size, A physical separation of the solids from the liquid phase. This separation is usually achieved by sedimentation (decantation), flotation or filtration.
What is coagulation sedimentation filtration and disinfection?
Coagulation – Chemicals with a positive charge are added to water. Dirt and other dissolved particles bind to the chemicals to form larger particles called floc. 2. Sedimentation – Floc settles to the bottom of the water supply due to its weight. The clear water on top is moved to the next stage.
What is disinfection in water treatment?
Disinfection. Disinfection is a physical or chemical process in which pathogenic microorganisms are deactivated or killed. Examples of chemical disinfectants are chlorine, chlorine dioxide, and ozone. Examples of physical disinfectants include ultraviolet light, electronic radiation, and heat.
What chemicals are used to disinfect the water supply?
Chlorine and chloramine are the major disinfectants used in public water systems.
What kind of process is coagulation filtration?
precipitative process
Coagulation/filtration is a precipitative process. The most widely used coagulants for water treatment are aluminum and ferric salts, which hydrolyze to form aluminum and iron hydroxide particulates, respectively.
What is the difference between filtration and disinfection?
Once the water passes through the filter, a large percentage of the original particles have been removed, but there is still a potential that microorganisms remain in the water. The process of disinfection is to treat the water in a way that kills or inactivates the remaining microorganisms in the water.
What are three types of disinfection?
Disinfection
- Chemical Disinfectants. Alcohol. Chlorine and chlorine compounds. Formaldehyde. Glutaraldehyde. Hydrogen peroxide.
- Miscellaneous Inactivating Agents. Other germicides. Metals as microbicides. Ultraviolet radiation. Pasteurization. Flushing- and washer-disinfectors.
- Regulatory Framework for Disinfectants and Sterilants.
What is disinfection and its types?
Disinfectants can be split into two broad groups, oxidizing and nonoxidizing. Oxidizing disinfectants include the halogens, chlorine, iodine, bromine, and chlorine dioxide, and oxygen-releasing materials such as peracetic acid and hydrogen peroxide.
How does chlorine work as a disinfectant?
Chlorine kills pathogens such as bacteria and viruses by breaking the chemical bonds in their molecules. Disinfectants that are used for this purpose consist of chlorine compounds which can exchange atoms with other compounds, such as enzymes in bacteria and other cells.