Applications of Compressed Air in Wastewater Treatment
June 27, 2024
Ensuring the correct treatment of industrial wastewater is a necessity for many industries, and it must be done correctly to eliminate hazardous compounds.
Many industries manufacture or use complex organic compounds—such as pesticides or petrochemicals—so their wastewater is contaminated. Ensuring the correct treatment of this industrial wastewater is a necessity for many of these industries. because by being able to reuse part of them, they not only save on costs for water consumption, but also reduce water pressure on the planet.
Content
We'll explain four of the main applications of compressed air in wastewater treatment:
1. Sand Removal by Air
Air sand removal is the first mechanical step of the wastewater treatment process, where sand and other particles are removed from the water.
In this process, compressed air is used to separate the dirt from the water. These sand removal chambers are usually limited to a depth of 6 to 16 feet (2 to 5 meters), so a lower pressure level is required. As the volume of the tanks is also quite small compared to other tanks in the plant, the required airflow is also quite limited. A reliable and simple solution is often a good choice for this first treatment step.
Mainly, we can find ZL three-lobe blowers in this application.
2. Aerobic Treatment
Aerated ponds, activated sludge, MBR, MBBR, SBR, .... There is a wide range of aerobic treatment processes present in a wastewater treatment plant, ranging from small capacities (<1 000 PE) to giant capacities (>1 000 000 PE), and from simple to complex processes. Everyone depends on the oxygen supply to survive, literally.
As the amount of wastewater that needs to be purified varies throughout the day, the amount of compressed air needed also varies. A variable speed drive helps control the amount of compressed air by matching airflow and energy consumption to flow demand. You can further optimize your diffuse oxygen control by adding a central controller that controls both pressure and flow for multiple blowers, such as our Optimizer 4.0.
Our certified oil-free air blowers (Class 0) help you protect the water quality, as no oil is added to the air during the compression process and therefore to the water.
Whether you're looking for a solution for a small or large capacity plant, we can always help you choose the right solution from our extensive portfolio.
Suitable blowers for this application can be ZLs, ZS screw blowers or ZB VSD+ magnetic levitation centrifuges.
Meet the ZS VSD+
Meet the ZB VSD+
3. Filter Backwash
Regular backwashing of filters is an effective technique used in many wastewater treatment plants to prevent filter clogging.
Using air during the filter backwashing process helps to return any accumulated sand or dirt.
The number of air wash cycles per day varies by plant. Some plants require several starts per hour, but the number of hours a blower runs is usually limited.
For this application, simple and reliable solutions with a fixed airflow (fixed motor speed) that require a minimum service level and a low initial capital investment are often the most interesting option.
The right blowers for this application are the ZL blowers.
4. Plant Air
Pneumatic valves are used throughout the water treatment plant to control variable water flows and modulate the treatment process to achieve the required effluent quality. The distribution of air flows to the different treatment tanks is also handled by pneumatic valves.
Medium pressure and low pressure air compressors are perfectly suited to this compressed air application.
Frequently Asked Questions
What equipment do I need for wastewater treatment?
Among the necessary machinery are medium and low pressure blowers. Atlas Copco offers these solutions with models such as the ZS (VSD+), ZB (VSD+) and ZL (VSD).
What applications does compressed air have in wastewater treatment?
Compressed air can help in processes such as backwashing, air sand removal, aerobic treatment, and plant air.
Why use blowers in wastewater treatment?
A Class 0 certified blower will ensure that wastewater treatment reaches its optimal operation, completely removing any contaminants that may be present in the water, such as chemical components.