What Is the Best Method for Wastewater Treatment?

Written by AOS Treatment Solutions on November 10, 2017
wastewater treatment methods

Wastewater is generally defined as water that has already been used in some capacity. Water from homes, businesses or industry is considered wastewater. Melted snow and runoff water from outdoor activities is also wastewater. There are several important reasons why you need to pay careful attention to how wastewater is processed and the different methods by which to treat it.

Why Treat Wastewater?

Wastewater can contain chemical, biological or physical pollutants. This can make it unsafe for human uses. It can potentially cause severe illness if untreated wastewater gets into the public drinking supply. Most wastewater is usually released back into the environment after treatment.

What Treatment Processes Are Used?

There are several steps you would normally take when treating wastewater in a municipal facility. According to NYC Environmental Protection, wastewater from New York City goes through five distinct processes that include preliminary, primary and secondary treatments, as well as disinfection and sludge treatment. Most treatment facilities employ similar steps or combine steps when treating wastewater.

1. Preliminary/Primary

Preliminary treatment normally includes screening the water to remove large objects and debris. Wastewater pretreatment can include everything from twigs and rocks to bottles and diapers. For industrial users, nation pollutant discharge elimination system (NPDES) sets wastewater pretreatment standards that are more strict.

2. Secondary

This is where your treatment options begin to diverge. Coagulation, along with flocculation, are methods that require a combination of chemicals. These processes cause particles to stick together so at a later point they can be more easily filtered out. Aluminum sulfate is a chemical often used in this process. After these insoluble fragments settle at the bottom through sedimentation, the purified water is filtered out. Filtration involves using a variety of filters to catch particles as the water flows through.

More about the primary and secondary treatment of wastewater here.

3. Disinfection

This is sometimes referred to as the tertiary treatment phase. Chlorine and chloramines are chemicals often used during the water treatment disinfection process. UV radiation is also sometimes used to disinfect water.

4. Sludge Treatment

The final stage of treating water will often include removing a sludge that is sometimes referred to as biosolids. According to Water Use it Wisely, the byproduct of sludge dewatering systems is sometimes used for agricultural purposes.

methods of wastewater treatment

What Treatment Methods Are Best?

The previous section details the processes involved in treating wastewater. Biotech articles states that the specific methods used generally fall into three categories.


Biological methods are normally put in place when the water will be used for drinking purposes. Aerobic treatment and fermentation are both biological methods.


Physical methods include sedimentation, aeration and filtration. Sand filters are sometimes used in the oil water separation process to remove oil and grease particles.


Chlorine is the chemical most often used in treating sewage and other types of wastewater. The process is called chlorination. This is the most effective means of destroying a variety of viruses and bacteria. A method known as neutralization is effective when treating industrial wastewater. Lime is sometimes used when treating acidic water.

What treatment solutions you’ll need will likely be determined by the type of wastewater, what contaminants are in the water and what the water will be used for after it’s treated. The best methods for treating wastewater should always coincide with regulations required in the state and locality where your facility is located. The methods used should also be as environmentally safe as possible.

Future Water Treatment Methods to Look For

Water treatment is a critical foundation of society. By expanding access to clean drinking water, safe water for home use and recycled water for agricultural purposes, water treatment improves the quality of life and security of millions of Americans each year. As technology has become more advanced, several unique and promising water treatment methods have begun to emerge, from systems for drought conditions to devices for hiking.

1. Desalinization

Right now, desalination plants produce more than 3.5 billion gallons of fresh water each year. As states like California, Texas and Colorado face record-breaking drought conditions, desalinization becomes increasingly important, and it is currently regarded as one of the potential primary methods for delivering fresh water to drought-ridden communities.

To turn salinated ocean water into fresh water, these plants use the processes of reverse osmosis and multi-stage flash distillation. These processes remove the salt from the water and make it safe for human consumption and use.

2. Sono Arsenic Filtering

The winner of the 2007 Grainger Challenge Prize was a George Mason University Professor named Abul Hussam. Hussam won the prize because he developed a life-saving water filtration technology known as the Sono Arsenic Filter.

Designed to take in groundwater and make it safe for human consumption by filtering arsenic out, the Sono filter is currently being used in places like Bangladesh and other Indian communities where safe drinking water is difficult or impossible to come by.

3. LifeStraw

LifeStraw is a portable, easy-to-use personal water filter developed in Switzerland. Designed for use by explorers and mountaineers, LifeStraw is small enough to be worn on a cable around a person’s neck. LifeStraw allows an individual to bend down and drink from any creek, lake or water source, exactly as one would drink through a standard straw.

As the water is pulled into the individual’s mouth, it passes through a series of filters that remove toxins and contaminants and make the water safe for consumption. While the LifeStraw is still working toward widespread distribution, it stands out as a potential water filtration and treatment solution for communities with contaminated water around the world.

4. Membrane Filtration Technology

Unlike LifeStraw and the Sono filter, both of which are handheld technologies, membrane filtration technology uses a membrane system (either low pressure or high pressure) to remove toxins and contaminants from water through the processes of ultrafiltration, microfiltration, nanofiltration and reverse osmosis.

Ideal for use in the food processing and other commercial industries, this is a technology that has existed since the 1980s, but stands to become much more popular in the coming years.

5. Ultraviolet Irradiation Technology

Made popular by the waste water treatment industry, UV irradiation technology uses UV light to remove germs and other contaminants from water supplies. Since the early 1950s, this technology has been used at hundreds of water treatment plants across the country and thousands of water treatment plants around the world. As safe drinking water becomes harder to access, UV irradiation technology will become more widespread.

Water treatment is a complex and critical service that has historically been expensive and time-consuming. Luckily, these five promising technologies have the potential to make clean drinking water much more accessible to communities around the world in the coming years.

Why Choose AOS for Your Water Treatment Needs?

You need a company that has extensive experience and a proven track record in treating public water systems. AOS has been providing consultation services, technical support and customized wastewater treatment solutions since 1999. AOS offers cost-effective groundwater treatment solutions for municipal water supplies.

It’s critical to effectively treat wastewater so it can be reused or safely put back into the environment. AOS can provide standard as well as customized solutions that can meet all your wastewater needs.

Contact AOS today for more information on our water treatment consulting services.


Posted Under: Wastewater Treatment Solutions