What is air scouring in water treatment?

Have you ever wondered about the processes that ensure the water flowing from your faucets is clean, clear, and safe? One crucial process in water treatment is ‘Air Scouring.’ This simple yet ingenious method removes sediment, biofilm, and mineral scale from your water systems. Our water workers use high-velocity, low-pressure air to clean water mains and membrane surfaces effectively, efficiently, and cost-effectively. This method surpasses traditional cleaning approaches. In this document, we will explore what is air scouring in water treatment and the purpose, process, and benefits of air scouring in our water treatment systems.

What is air scouring in water treatment?

Air scouring in water treatment is a process that involves the injection of high-velocity and low-pressure air into a water distribution system to remove sediment, biofilm, and soft mineral scale, thus improving water quality and flow capacity. This method is used to clean water mains and is considered an alternative to traditional cleaning methods such as unidirectional flushing or physical cleaning with a “pig” or “swab.” Air scouring is also used in membrane filtration systems to clean the membrane surface by rapidly abrading and scraping it with pressurized air bubbles. The process provides cleaner mains, better flow, and reduced pumping costs using less water than other cleaning methods.

What is the purpose of air scouring?

The purpose of air scouring in water treatment remove sediment, biofilm, and soft mineral scale from water distribution systems, thus improving water quality and flow capacity. When air scouring precedes the water wash, it is intended to break up and detach deposits ready to be flushed out. This process involves the injection of high-velocity and low-pressure air into the system, creating a vortex that travels through the isolated section, removing impurities. Air scouring cleans the membrane surface in membrane filtration systems by rapidly abrading and scraping it with pressurized air bubbles.

What is the process of air scouring?

Air scouring is a cleaning process for water mains and membrane surfaces in water treatment systems. The process involves several steps:

1. Isolation of the Section: A specific section of the water main or membrane system is isolated for cleaning.
2. Removal of Water: The existing water within the isolated section is removed using high-velocity and low-pressure air. This is achieved by injecting filtered ‘oil-free’ compressed air into the mains via a hydrant, which propels a small volume of water at high velocity.
3. Controlled Water Addition: A controlled amount of water is then introduced to create slugs of water. This is done by slightly opening a valve upstream of the entry point, allowing controlled amounts of water to mix with the compressed air.
4. Creation of a Vortex: The mixture of air and water creates a vortex or slug flow that travels through the isolated section. This vortex has enough force to remove sediment, biofilm, and soft mineral scale from the interior surfaces of the water main or membrane.
5. Expulsion of Sediment: The air, water, and any dislodged sediment and biofilm are ejected from the system through a hydrant or other outlet at the end of the section being cleaned.
6. Restoration of Service: Once the water exiting the line is clear, indicating that the cleaning process is complete, service is restored to the section.
7. Water Quality Testing: In some cases, water quality testing is conducted before and after the air scouring process to assess the effectiveness of the cleaning and ensure water safety.

What are the benefits of air scouring?

The primary benefits of air scouring include the removal of sediment, improved water quality, increased flow capacity, improved membrane cleaning, reduced pumping costs, and using less water compared to other cleaning methods.

Removal of Sediment: Air scouring helps remove sediment, biofilm, and silt from pipes, leading to a cleaner water system and reducing dirty water complaints.

Improved Water Quality: By dislodging biofilms and sediment, air scouring enhances water quality and reduces discolored water complaints.

Increased Flow: It can lead to better flow in water and sewer mains by removing buildup, thus improving the overall flow capacity.

Improved Membrane Cleaning: Air scouring cleans the membrane surface in membrane filtration systems, leading to improved system performance and reduced backwash duration and flux.

Cost Reduction: Air scouring can reduce costs by eliminating the need for temporary ground piping, reducing pumping costs, and using less water than other cleaning methods.

In conclusion

Air scouring is an innovative method for improving water quality and flow capacity. It is a testament to our commitment to ensuring public health and safety. Using air to remove sediment and biofilm has numerous benefits, including cleaner mains and reduced pumping costs.  As we examine water treatments and techniques, it’s important to remember that these seemingly technical steps are crucial to maintaining the health and well-being of our communities. So, the next time you turn on your faucet and enjoy the clear, flowing water, take a moment to appreciate the processes, such as air scouring, that work behind the scenes to provide you with safe and clean water.

If you are seeking top-quality water treatment solutions, we invite you to reach out and Contact Us. As a leading supplier in the industry with years of experience under our belt, we’re committed to delivering excellence for your specific water treatment needs. Harness the power of air scouring and elevate the quality of your water. After all, the clarity and quality of water should never be compromised. Contact us today to discuss how we can help make your water safer and cleaner.