How to select the proper blower for your wastewater treatment?


1. How does the air compressor work for the sewage treatment plant?

The Air Compressor plays a key role in wastewater treatment. In the sewage industry, the compressed air is mainly used for the following applications:

Sewage Treatment Process

① Wastewater disposal—The compressed air is used in a central vacuum system to drive the disposal of the water. At the same time, the wastewater is collected, drained, and eliminated.

② Digestion tank cleaning and maintenance—In the digestion tank, oxygen plays an important role in sludge digestion. The air compressor for the sewage treatment plant offers pressurized air that mixes the sludge with oxygen to boost gas yield and retention time. The warm compressed air usually improves the decomposition process.

③ Backwashing sand filtration—In the filtration process, there might be sand agglomeration in the filter bed. The blowers for the sewage treatment plant are necessary to pump in the backwash water for the cleaning.

④ Desalination—The blower for the sewage treatment plants is also needed to remove the dissolved salts from water enabling freshwater production from seawater or brackish water.


In summary, the air compressor for sewage treatment plants is needed in almost every process of wastewater treatment.


2. What are the main types of blowers?

Mainly there are three types of blowers for sewage treatment plants: the positive displacement type, the centrifugal-type and the high-efficiency type

Positive displacementIn this type of blower, the air or gas enters through an expanding section on one side and exits through a decreasing section on the other side; by decreasing the volume, the air is compressed.

Rotary Screw Blower

Lobe Air Blowervvv

More specifically, there are two types of positive displacement blower: the rotary screw blower and the roots blower. The roots blower (rotary lobe blower) acts as a pump for the air as it goes into the motor, whereas the rotary screw blower is more like a screw air compressor. 

Centrifugal blowerThe centrifugal blower is also known as a turbo blower. This kind of centrifugal blower is equipped with rotating impellers and when the air passes through the vanes, it increases in both speed and volume.


High-efficiency blowerIt’s the only kind of blower that uses magnetic bearings, which makes the air compression extremely efficient.


3. How to choose the right blower technology?

In the effluent treatment plant or wastewater treatment plant, the running cost of the blower for the sewage treatment plant constitutes approximately 60% of the energy cost of the entire plant. This is mainly that the air compressor for the sewage plant has to run 24×7 to support the biological process in the digestion tank.

Therefore, it’s crucial to choose the right blower technology to gain the best energy efficiency:

Centrifugal Blower

Centrifugal blower—The centrifugal blower is an ideal tool to maintain a continual gas transfer: when the gas passes through a centrifugal blower, it increases in kinetic energy; thus when the gas exits the turbo blower, the new gas enters automatically to normalize the gas pressure.


Positive displacement blower In terms of this type of blower for the sewage treatment plants, the rotary screw blower is an average of 30% better in energy efficiency compared to the traditional rotary lobe technology, which is also known as roots blowers. The rotary screw blower helps to save money by energy savings and also reduces the environmental impact.


4. Why choose Sollant blowers for sewage treatment plants?

The Air Compressors for Sewage Treatment Plant are the main products of Sollant. Our star products are Air Suspension Single Stage Centrifugal Blower and Oil-Free Screw Compressor.

Both the Air Suspension Blower and the Rotary Screw Blower are designed with cutting-edge technology: equipped with the PM VSD motor, both of these two products are oil-free, environment-friendly and highly efficient. And both of them can be adjusted in terms of frequency conversion: more specifically, the adjustment range of the Oil-free screw Compressor & Screw Blower is wider than that of the Air Suspension Centrifugal Blower.

Air suspension single stage centrifugal blowerThis Air Suspension Blower adopts the air bearing, which is the most advanced technology reducing the mechanical friction in the operation. Besides, unlike the positive displacement blower that is limited in the air volume, this centrifugal blower can be used in applications requiring large air volume.

Air suspension single stage centrifugal blower

For more detail, please click: Sollant Air Suspension Centrifugal Blower

Oil-Free Screw Blower—Compared with the Air Suspension Centrifugal Blower with a complex and delicate structure , this rotary screw blower is simpler and requires less in the environmental condition. Besides, the oil-free technology improves the efficiency of operation.

Oil-free screw compressor and screw blower

For more details, please click: Sollant Oil-free Screw Blower