
Wastewater Treatment Process
- Preliminary treatment: Preliminary wastewater treatment precedes primary treatment. Its main function is to minimize operational problems and to protect subsequent treatment units.
- Primary treatment: The primary wastewater treatment process is the physical or chemical treatment for the removal of materials that will either float or readily settle out by gravity.
- Secondary treatment: Secondary wastewater treatment uses biological and chemical means for the substantial elimination of dissolved organics and colloidal materials.
- Advanced treatment: Advanced wastewater treatment is used to remove pollutants by methods other than those used in conventional treatment methods mentioned above.
What are the steps in waste water treatment?
- Stage One — Bar Screening.
- Stage Two — Screening.
- Stage Three — Primary Clarifier.
- Stage Four — Aeration.
- Stage Five — Secondary Clarifier.
- Stage Six — Chlorination (Disinfection)
- Stage Seven — Water Analysis & Testing.
- Stage Eight — Effluent Disposal.
What is the best method for wastewater treatment?
What Treatment Processes Are Used?
- Preliminary/Primary. Preliminary treatment normally includes screening the water to remove large objects and debris. ...
- Secondary. This is where your treatment options begin to diverge. ...
- Disinfection. This is sometimes referred to as the tertiary treatment phase. ...
- Sludge Treatment. ...
What are the types of wastewater treatment processes?
Types of Effective processes to treat Wastewater:
- Biological water treatment: This method breaks down organic matter in the waste water by using decomposed biological methods carried out; microorganisms are also involved in metabolizing organic matter. ...
- Chemical Water Treatment: In this process chemicals are used to purify the water. ...
- Physical Water Treatment:
What are the biggest problems in wastewater treatment?
- Increasing/expanding regulations. Concerns over increasing regulations consistently ranked near the top of the list for every geographical region, pushing the topic into the No. ...
- Technology changes. Information technologies jumped to the No. ...
- Aging workforce. In the No. ...
- Water scarcity. ...

What is the process in wastewater treatment?
Treatment StepsStep 1: Screening and Pumping. ... Step 2: Grit Removal. ... Step 3: Primary Settling. ... Step 4: Aeration / Activated Sludge. ... Step 5: Secondary Settling. ... Step 6: Filtration. ... Step 7: Disinfection. ... Step 8: Oxygen Uptake.
What are the 3 stages of wastewater treatment?
There are three main stages of the wastewater treatment process, aptly known as primary, secondary and tertiary water treatment. In some applications, more advanced treatment is required, known as quaternary water treatment.
What are the four major processes in wastewater treatment?
Four common ways to treat wastewater include physical water treatment, biological water treatment, chemical treatment, and sludge treatment. Let us learn about these processes in detail. In this stage, physical methods are used for cleaning the wastewater.
What is wastewater treatment and why is it important?
The major aim of wastewater treatment is to remove as much of the suspended solids as possible before the remaining water, called effluent, is discharged back to the environment. As solid material decays, it uses up oxygen, which is needed by the plants and animals living in the water.
What are the three types of wastewater?
Types of sewage There are three types of wastewater, or sewage: domestic sewage, industrial sewage, and storm sewage. Domestic sewage carries used water from houses and apartments; it is also called sanitary sewage.
What are the benefits of waste treatment?
Here are the five major benefits of wastewater treatment.Provides clean, safe water processed. To many, it is unknown to them that wastewater can be turned into reusable water. ... Saving you money. ... Beneficial to the environment. ... Saving water. ... A way to minimise waste.
What are the 7 steps in wastewater treatment?
The Wastewater Treatment ProcessStage One — Bar Screening. ... Stage Two — Screening. ... Stage Three — Primary Clarifier. ... Stage Four — Aeration. ... Stage Five — Secondary Clarifier. ... Stage Six — Chlorination (Disinfection) ... Stage Seven — Water Analysis & Testing. ... Stage Eight — Effluent Disposal.
What is the difference between water treatment and wastewater treatment?
Water treatment is done to water before it is sent to a community, while wastewater treatment is done to water that has been used by the community. Water treatment has higher standards for pollution control because it is assumed that any drop of distributed water could be consumed by a person.
What is wastewater treatment PDF?
Wastewater treatment is the process. and technology that is used to remove most of the contaminants that are found in. wastewater to ensure a sound environment and good public health. Wastewater. Management therefore means handling wastewater to protect the environment to ensure.
What are the three main purposes of water treatment?
Water treatment is a process involving different types of operations (physical, chemical, physicochemical and biological), the aim of which is to eliminate and/or reduce contamination or non-desirable characteristics of water.
What is a product of wastewater treatment?
Sewage sludge is the solid, semisolid, or slurry residual material that is produced as a by-product of wastewater treatment processes. This residue is commonly classified as primary and secondary sludge.
What are sources of wastewater?
Wastewater is 'used water' from any combination of the sources listed below:Domestic.Industrial.Commercial.Agricultural activities.Surface runoff or storm water.Any sewer inflow or sewer infiltration.Horticultural.Aquaculture effluent.
Q. What are the three stages of wastewater treatment?
Ans: There are three main stages of the wastewater treatment process; they are primary, secondary and tertiary process.
Q. What is the process of a wastewater treatment plant?
Ans: The process of wastewater treatment plant is as follows: 1. Primary treatment: It is the initial stage. Waste water is passed through rotating...
Q. What are the four stages of wastewater treatment?
Ans: The four stages of wastewater treatment are: 1. Physical water treatment 2. Biological water treatment 3. Chemical treatment 4. Sludge treatment
Q. What are the two types of wastewater treatment?
Ans: There are two wastewater treatment plants, (i) chemical or physical treatment plants, (ii) biological wastewater treatment plants.
Q. What are the types of wastewater treatment?
Ans: Types of wastewater treatment system are; A. Effluent treatment plants B. Sewage treatment plants C. Common and combined effluent treatment pl...
Q. What are the main sources of wastewater?
Ans: The main sources of wastewater are Domestic wastewater, agricultural wastewater, industrial wastewater, petroleum.
What is wastewater treatment plant?
Wastewater treatment plant is the process of removing contaminants from wastewater and converting it into effluent that can be recycled into the water cycle. Once returned to the water cycle, the effluent has an acceptable environmental impact or is reused for a variety of purposes. A wastewater treatment plant is where the treatment ...
How does a sewage treatment plant filter wastewater?
The wastewater that enters the sewage treatment plant is first filtered through bar screens, a process known as screening. The bar screen separates large trash objects from the wastewater, such as rags, sticks, cans, plastic bags, napkins, sanitary towels, and so on. As a result, screening removes large pieces of trash from the wastewater.
What is the difference between biogas and sludge?
As a result, wastewater treatment (or sewage treatment) yields two useful products: (i) biogas and (ii) sludge. Biogas is used as a fuel, and sludge is used as manure (or fertiliser).
What is the solid component of sewage?
The majority of the solid organic matter (faeces, for example) settles as sludge on the sloping bottom of the sedimentation tank. As a result, the solid component of sewage is known as sludge .
Why is activated sludge returned to the aeration tank?
Some of the activated sludge is returned to the aeration tank to boost the population of aerobic bacteria and accelerate the cleaning of watery waste. The digester tank receives the remaining activated sludge. The water in the second sedimentation tank contains very little organic material and suspended matter.
What is WWTP in water treatment?
WWTP is an abbreviation for Waste-Water Treatment Plant. A wastewater treatment plant is also referred to as a sewage treatment plant. A modern wastewater treatment plant treats wastewater or sewage through a series of physical, chemical, and biological processes until it becomes fit to be discharged into the environment.
Where is sludge removed from sedimentation tanks?
The sludge is removed from the bottom of the first sedimentation tank and placed in a large, closed tank known as the digester tank. Many different types of anaerobic bacteria decompose the organic matter in sludge in the digester tank to produce biogas.
What is wastewater treatment?
Wastewater treatment is a process to treat sewage or wastewater to remove suspended solid contaminants and convert it into an effluent that can be discharged back to the environment with acceptable impact. The plants where the wastewater treatment process takes place are popularly known as Wastewater treatment plants, ...
Why is wastewater treatment important?
So, Wastewater treatment plants plays a major role in keeping environment clean and saving numerous lives.
What is a sewage treatment plant?
Sewage treatment plants eliminate contaminants from wastewater and household sewage. It uses physical, chemical, and biological processes to remove physical, chemical and biological contaminants to make the water and solid waste reusable. Combined Effluent Treatment Plants are established where a cluster of small scale industries are present.
How is suspended solid removed from wastewater?
Suspended solid materials from the wastewater are removed by the sedimentation primary treatment. Other floatable materials like oils, fats, etc are removed using dissolved air floatation treatment. Primary wastewater treatment, in general, removes about 60% of suspended solids from wastewater.
Why is industrial wastewater considered domestic wastewater?
Industrial wastewater results because of chemical and manufacturing industry discharges. So, wastewater is essentially the used water that has been affected by domestic, commercial, or industrial use. Domestic wastewater is relatively easy to treat as compared to industrial wastewater due to its high-strength nature.
Why is domestic wastewater generated?
Domestic wastewater is generated because of activities like bathing, washing, using the toilet, etc in residences, restaurants, and businesses. Surface rainwater runoff is generated due to the mixing of debris, grit, nutrients, and various chemicals. Industrial wastewater results because of chemical and manufacturing industry discharges.
What are the pollutants that are normally present in wastewater?
Typical pollutants that are normally present in wastewater are: Bacteria, viruses, and disease-causing pathogens. helminths (intestinal worms and worm-like parasites) Toxic Chlorine compounds and inorganic chloramines.
Why Treat Wastewater?
It's a matter of caring for our environment and for our own health. There are a lot of good reasons why keeping our water clean is an important priority:
Wastewater treatment
The major aim of wastewater treatment is to remove as much of the suspended solids as possible before the remaining water, called effluent, is discharged back to the environment. As solid material decays, it uses up oxygen, which is needed by the plants and animals living in the water.
What happens after a wastewater treatment plant meets all permit specifications?
After meeting all permit specifications, clean water is reintroduced into the environment. Although testing is continuous throughout the wastewater treatment process to ensure optimal water flow, clarification and aeration, final testing is done to make sure the effluent leaving the plant meets permit specifications.
What is the process of removing large items from the influent?
Removal of large items from the influent to prevent damage to the facility’s pumps, valves and other equipment .#N#The process of treating and reclaiming water from wastewater (any water that has been used in homes, such as flushing toilets, washing dishes, or bathing, and some water from industrial use and storm sewers) starts with the expectation that after it is treated it will be clean enough to reenter the environment.#N#The quality of the water is dictated by the Environmental Protection Agency (EPA) and the Clean Water Act, and wastewater facilities operate to specified permits by National Pollutant Discharge Elimination System (NPDES). According to the EPA, The Clean Water Act (CWA) establishes the basic structure for regulating discharges of pollutants into the waters of the United States and regulating quality standards for surface waters. Under the CWA, EPA sets wastewater standards for industry. The EPA has also developed national water quality criteria recommendations for pollutants in surface waters. EPA's National Pollutant Discharge Elimination System (NPDES) permit program controls discharges.#N#As an example of expected standards, the Biochemical Oxygen Demand (BOD) of average wastewater effluent is 200 mg/L and the effluent after treatment is expected to be >30 mg/L. It is crucial a wastewater facility meets these expectations or risk stiff penalty.#N#The physical process of wastewater treatment begins with screening out large items that have found their way into the sewer system, and if not removed, can damage pumps and impede water flow. A bar screen is usually used to remove large items from the influent and ultimately taken to a landfill.
Why is wastewater pumped into a secondary clarifier?
Treated wastewater is pumped into a secondary clarifier to allow any remaining organic sediment to settle out of treated water flow. As the influent exits the aeration process, it flows into a secondary clarifier where, like the primary clarifier, any very small solids (or fines) sink to the bottom of the tank.
What is activated sludge?
These small solids are called activated sludge and consist mostly of active bacteria. Part of this activated sludge is returned to the aeration tank to increase the bacterial concentration, help in propagation, and accelerate the breakdown of organic material. The excess is discarded.
What happens if water flows too slow?
If the water flow is too slow, it impacts the process up stream. The solids that fall to the bottom of the clarifier are know as sludge and pumped out regularly to ensure it doesn’t impact the process of separation. The sludge is then discarded after any water is removed and commonly used as fertilizer.
What is the function of an aeration tank?
The primary function of the aeration tank is to pump oxygen into the tank to encourage the breakdown of any organic material (and the growth of the bacteria), as well as ensure there is enough time for the organic material to be broken down.
What is a bar screen in wastewater treatment?
A bar screen is usually used to remove large items from ...
Importance of Wastewater Treatment Process
Wastewater contains a large number of toxins that might harm the environment; thus, treatment is essential.
Stages of Wastewater Treatment Process
Unit Operation: It is a process in which wastewater treated by Physical Method
Flow Diagram for Wastewater Treatment Process
Note: – All treatment plants have different equipment depending upon what they want to achieve or other several factors.

How Is Wastewater formed?
Wastewater Treatment Process
- The sequence of wastewater treatment processes are usually characterized as: 1. Preliminary treatment 2. Primary treatment 3. Secondary treatment 4. Tertiary treatment or Advanced treatment
Basic Design Considerations
- Wastewater Treatment Requirement:The requirement of wastewater treatment is dependent on the following parameters: 1. the influent characteristics, 2. the effluent quality requirements, and 3. the wastewater treatment processes that produce an acceptable effluent. Laboratory tests of wastewater samples are performed to find out influent characteristics. Effluent quality requirem…
Types of Wastewater Treatment Plants
- For the betterment of society, environment, and the future, wastewater treatment should be taken seriously. The outbreak of numerous waterborne diseases can be prevented by proper wastewater treatment. So, Wastewater treatment plants play a major role in keeping the environment clean and saving numerous lives. There are basically three types of Wastewater tre…
Top Online Courses on Wastewater Treatment
- Wish to know more about waste-water treatment! Then the following video courses are for you. Click on the subject below and review the details and then proceed to take the course. 1. Membrane Technology for Water and Wastewater Treatment 2. Water Treatment Process Design 3. Membrane Technologies Used in Water and Wastewater treatment 4. Basics of Water Desalin…