Air blower is the equipment that supplies air to the aerobic tank in wastewater treatment — pushing air through the diffuser system (disc/pipe) at the tank bottom so that aerobic microorganisms can break down organic matter. Choosing the right unit ensures adequate oxygen, stable microbial activity, and energy savings (the machine runs almost 24/7).
Step 1 — Calculate Pressure Based on Tank Depth
The required air blower pressure ≈ the water column height above the air diffuser head + pressure loss through the diffusers and piping. Rule of thumb: every 1 m of water column ≈ ~100 mbar. Example: a tank 5 m deep with diffusers placed 0.3 m from the bottom → water column ~4.7 m ≈ 470 mbar; adding diffuser + pipe losses ~150 mbar → the machine needs approximately 620 mbar (select with margin up to ~700 mbar).
Step 2 — Calculate Air Flow Rate Based on Oxygen Demand
Air flow rate depends on the tank’s oxygen demand (based on BOD/COD loading and water flow rate) divided by the oxygen transfer efficiency of the diffuser system (SOTE, %). Deeper tanks and fine-bubble diffusers yield higher SOTE → less air required. This is a design calculation — TKT engineers assist with sizing based on your actual tank data.
Step 3 — Choose the Technology: Roots or Screw
Shallow to medium tanks, modest budget → Roots air blower. Deep tanks, high capacity, continuous operation requiring energy savings → screw air blower (higher efficiency at elevated pressure). See the detailed comparison in the article how to choose the right-sized air blower.
Step 4 — Oil-Free Air & Control by Dissolved Oxygen
Air supplied to wastewater must be 100% oil-free to avoid oil films on the surface and disruption to microorganisms — Roots/screw air blowers meet this requirement. Installing a variable frequency drive (VFD) to control air flow rate based on a dissolved oxygen (DO) sensor keeps DO stable and reduces energy consumption during low-load conditions.
Step 5 — Redundancy & Operation
Aeration systems typically include a standby unit (N+1) with alternating operation to allow maintenance without interruption. Keep spare parts (drive belts, air filters, gearbox oil) on hand per manufacturer recommendations.
Thái Khương Pumps is an authorized distributor of Aerzen (Germany) and Robuschi (Italy) air blowers for wastewater treatment — with CO-CQ documentation and spare parts. Send your tank data (flow rate, depth, loading) to receive a sizing consultation.
Air Blower Models Available in Vietnam
Thái Khương Pumps is an authorized distributor of two complementary brands for wastewater treatment — Robuschi (Italy) for Roots/lobe blowers and Aerzen (Germany) for screw and turbo blowers:
Oil-free air for biological tanks — select size based on air flow rate and tank depth. View model specifications →
Oil-free air for biological tanks — select size based on air flow rate and tank depth. View model specifications →
Aerobic tanks rely entirely on this assembly — air filters, oil, and safety valves need checking before peak-load season: see air blower spare parts in stock.
See also aeration air blowers for wastewater treatment systems distributed by Thái Khương Pumps.
Frequently Asked Questions
Where are air blowers used outside of wastewater treatment?
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Pneumatic conveying of bulk materials (cement, plastic pellets), aquaculture, filter backwashing, and process air supply. Wastewater treatment remains the most common application with aerobic biological tanks.
What periodic maintenance does an air blower require?
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Inlet air filter (clogs quickly in humid seasons), lubricating oil of the correct type and change interval, drive belts on belt-driven machines, and safety valves. If the machine stops, aerobic tank microorganisms deteriorate quickly — an N+1 standby arrangement is recommended.
Are spare parts for Aerzen and Robuschi air blowers available?
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Thái Khương Pumps is an authorized distributor of Aerzen (Germany) and Robuschi (Italy), maintaining a warehouse of over 5,000 spare part numbers (SKUs) — see the full catalogue of air blower spare parts in stock by model.
Spare parts for air blowers: see the in-stock catalogue by model.
Send your air flow rate, pressure (or tank depth) and application — Thái Khương Pumps engineers will advise on technology + machine size and provide a quotation with CO-CQ documentation within 24 hours. Request a quotation →
