Sewage Treatment: Needs, Process, Methods & Types of Plants
Wastewater from households and industries along with the water runoff from urban areas is conveyed to sewage treatment plant through efficient sewerage system. This is done for safe and economic sewage treatment and disposal of the resulting sludge. Both solid and dissolved pollutants are found in domestic and industrial wastewater. This includes excreta, urine, paper, chemicals, sanitary items, food residues, metal particles and various other contaminants.
Wastewater from all these various resources travels through the sewerage system to a sewage treatment plant where it is treated before being discharged into any water resources. Collecting and wastewater treatment has been a boon to mankind and the environment as. It has helped reduce water pollution and spread of various water borne diseases like cholera and typhoid.
If you are looking for sewage treatment plants, systems and solutions then we at IDS Water have it all and much more. Our goal is to connect you to numerous suppliers and vendors who are reputed in distribution and consultation of all kinds of wastewater technology related testing and components. They are also dedicated in offering you with exceptional and professional solutions for all your sewage treatment problems, needs and requirements.
Before you go through our suppliers and vendors directory we are sure that you would want to know more about sewage treatment. Continue reading this article to know more about it.
Why is Sewage Treatment Needed?
Sewage treatment is ideally done to ensure that the receiving water resources into which the effluent is finally discharged is not contaminated or polluted significantly. However, the degree of sewage treatment required will differ according to the type of receiving water resources. Therefore, a very high degree of wastewater treatment will be required if the effluent is discharged into a fishery or an upstream which is used for water supply. Whereas, a lower level of wastewater treatment may be acceptable for discharge to coastal waters where there is rapid dilution and dispersion.
Sewage Treatment: Pollutants, Sedimentation & Sludge
Sewage treatment involves the following:
- The removal of solids by sedimentation or physical screening
- The removal of fine and soluble suspended organic pollutants by adsorption and biological oxidation processes.
The by-product of both forms of sewage treatment is sludge. This has to be treated and used or disposed of in an economical and environmentally acceptable way. However, in practice, there are numerous sewage treatment process variations employed according to locality and the standard of effluent required.
Sewage Treatment Process
Sewage treatment process is designed to improve the quality of wastewater. Widely used terminologies include the following sewage treatment process
- Preliminary Treatment: This is the first stage of sewage treatment process. Here screens are used to take out large solid inorganic matters like paper, metals and plastics. This is followed by elimination of finer particles like silt and grit. Preliminary treatment process involves screening, grit removal, flow equalization, and fat and grease removal.
- Primary Treatment: In this stage of sewage treatment, wastewater passes through a primary sedimentation tank. It is here that gravity settling is used to remove solid particles of organic material from the suspension. The sludge collected in the tank is concentrated and then pumped away for further treatment.
- Secondary Treatment: This is a biological process wherein microorganisms that occur naturally are used to breakdown suspended and dissolved organic solids. It is also called activated sludge process.
- Tertiary Treatment: Disinfection is used in tertiary treatment to reduce pathogens that pose a risk to human as well as environment health.
- Sludge Treatment: Sludge collected during the treatment process contains a large amount of biodegradable material, which requires treatment by a different set of microorganisms, called anaerobic bacteria, which do not need oxygen for growth.
- Integrated Fixed Film Activated Sludge(IFAS): This process is aimed at reducing the level of nitrogen in existing sewage treatment plants.
Sewage treatment technologies under this process depend on type of wastewater treatment. However, typically a combination is selected. For any type of wastewater treatment there is no unique sewage treatment solution. Also, it is difficult to standardize sewage treatment solution by categorizing wastewater from different resources.
Sewage Treatment Process
Wastewater from various resources is disposed off in a way where it does not come in contact with people, animals and flies. This is called sewage system treatment.
There are different types of sewage systems treatment methods. These can be described as one-site systems and sewage or effluent systems.
An on-site system undertakes sewage treatment in a septic tank so that most of the sewage becomes effluent and is disposed of in an area close to the house or buildings. An example of an on-site disposal system consists of a septic tank and leach drains. Usually a sewage or wastewater treatment system disposes of the effluent in a centrally located place. This place is called a sewage lagoon or effluent pond.
However, sewage treatment process include treating:
- in a septic tank at each building
- just before the lagoon in a large septic tank or macerator system, or
On-Site Disposal Sewage Treatment Systems
All liquid waste from toilets, bathrooms, sinks, kitchen and laundry goes into pipes that carry it to a septic tank. The effluents from the tank are then disposed of through effluent disposal drains commonly known as French drains or leach. Both of these methods of disposing of wastewater are on-site disposal systems. However, remember that both these sewage treatment process of on-site disposal systems are installed and maintained properly. In this sewage treatment method, the effluent is soaked into the surrounding soil. Some soils such as clay or similar types do not allow proper soakage of the effluent.
Further, on-site disposal systems can be installed only in certain situations. For example, they can be installed:
- in areas that do not flood regularly
- in areas that do not have a high water table i.e. where there is no underground water close to the surface
- where the amount of wastewater to be disposed of is small
- where there is no drinking water supplies nearby
Effluent or Sewage Disposal System
In this sewage treatment method, large pipes to the lagoon transport the domestic wastewater that is collected. These pipes serve all the houses and other buildings in the community. Sewage treatment in this method takes place either in the septic tanks at the houses, buildings or at the lagoon. Also there are no French drains or leach.
Full Sewage Treatment Plant & System
In this wastewater treatment method, sewage from all resources enters waste and sewer pipes directly and is pumped to a lagoon. Note that there are three types of full sewage treatment process and these include:
- Sewage enters the lagoon without any sewage treatment
- Sewage goes through a series of cutting blades that aid in breaking up of the solid matters before it enters the lagoon. These blades are called macerators.
- The sewage can be treated in a large septic tank just before it enters the lagoon.
Types of Sewage Treatment Plant
Sewage treatment plants are absolutely essentially for effective treatment of effluents. There are many types of sewage treatment plants that differ in process by which it treats wastewater. Ideally, it can be classifies into the following types of systems:
All the aforementioned sewage treatment plants operate in different ways and produce effluent of differing quality. Additionally they all also cope with different types of usage to varying degrees of success. For e.g. some sewage treatment plants can tolerate being under loaded whereas some do not function as effectively. Also some sewage treatment plants are most efficient with higher loadings where other is not able to effectively process high levels of sewage.
Based on the above, one can understand that sewage treatment is very important to treat effluents before releasing it into receiving waters. Therefore, effective sewage treatment has become the need of the hour. We at IDS Water have all the facilities and much more to connect you with right suppliers and vendors for sewage treatment plants and solutions. So what are you waiting for? Just browse through our directory as it will provide you with the details of numerous prospective vendors and suppliers. They will help to meet all your wastewater treatment and technology requirements and needs.
Tags: Sewage Treatment Plant, Plants, Sewage Treatment Process, Method, Sewerage System, Systems, Pollutants, Wastewater Treatment, Water Resources, Pollution, Effluent, Effluents, Pipes, Solutions, Suppliers, Vendors, Filter, Directory