Air Operated Diaphragm Pump Supplier in Bangladesh
Bianfeng AODD pumps for acids, solvents, chemicals and ETP sludge. No electric motor at the pump, supplied with installation and after-sales support by Techno Bangla Creation.
What Is an Air Operated Diaphragm Pump?
An air operated diaphragm pump (AODD pump) is a positive displacement pump driven by compressed air instead of an electric motor. Air pushes two flexible diaphragms back and forth on a shared shaft, drawing liquid in and forcing it out. It moves acids, solvents, sludge and other difficult liquids.
An AODD pump is a transfer pump, not a precise dosing pump. For accurate chemical feed rates, see our chemical dosing pump page. For drums and small containers, see our drum and container pump.
- Air-driven, so no electric motor sits at the pump
- Body options from plastic to aluminium and stainless steel
- Suited to chemical transfer, sludge and filter press feed
- Installation and after-sales support in Bangladesh
Air Operated Diaphragm Pump Specifications
- Type
- Air operated double diaphragm pump, positive displacement
- Power source
- Compressed air
- Materials
- PVDF, PTFE, PP, aluminium alloy, stainless steel, cast steel
- Application
- Chemical transfer, acids, solvents, corrosive liquids, sludge transfer for dewatering, food processing
- Typical AODD range
- 0.25 ~ 4 inch ports (about 6 ~ 100 mm), about 19 ~ 1,100 L/min (about 1 ~ 66 m³/hr)
- Brand
- Bianfeng
- Origin
- China
The "typical AODD range" is the general industry span, not a Bianfeng limit. Port size, flow, air pressure, air use, solids size and materials depend on the model. Send us your duty and our engineers will confirm the datasheet values of the exact model.
How Does an AODD Pump Work?
- Compressed Air EntersAir from your compressor passes through a regulator into the pump's air valve.
- Air Pushes One DiaphragmThe air pressure moves one diaphragm outward. A linked shaft pulls the other diaphragm inward.
- Liquid Is Drawn InThe pulled-in chamber grows, and liquid lifts the inlet check ball and fills it.
- Liquid Is Pushed OutThe pushed-out chamber shrinks, closes its inlet ball and sends liquid through the discharge.
- Air Valve Shifts, Cycle RepeatsThe air valve switches sides, so the two chambers swap roles. Speed follows air pressure and back pressure.
Which Body and Diaphragm Material Should You Choose?
Match the material to your liquid first. Wrong material is the main cause of early failure.
| Part and material | Suits | Watch out for |
|---|---|---|
| Body: Polypropylene (PP) | Acids, alkalis and salt solutions at low cost | Aromatic solvents and strong oxidising acids |
| Body: PVDF | Strong acids and a wider chemical range, with higher temperature tolerance | Special chemicals such as hydrofluoric acid need a compatibility chart |
| Body: Aluminium alloy | Neutral liquids, oils, paints and clean water | Acids, caustic and brine attack it |
| Body: Stainless steel 316 | Food service, mild chemicals, solvents and abrasive liquids | Hydrochloric acid and chloride-rich liquids |
| Body: Cast steel or cast iron | Wastewater and sludge transfer | Corrosive chemicals |
| Diaphragm: PTFE | Widest chemical range and hot liquids | Stiff, so often paired with a flexible backing diaphragm |
| Diaphragm: Santoprene or EPDM | Water, wastewater and mild chemicals | EPDM swells in oils and hydrocarbons |
Guide values come from pump makers' material guides. Always check your liquid and concentration on a chemical compatibility chart, and confirm which diaphragm, ball and seat options the exact Bianfeng model offers.
AODD Pump vs Centrifugal Pump
Both move liquid. They suit very different liquids and duties.
| Feature | AODD Pump | Centrifugal Pump |
|---|---|---|
| Working principle | Reciprocating diaphragms move a fixed volume each stroke | A spinning impeller adds speed and pressure |
| Power source | Compressed air, no electricity at the pump | Electric motor |
| Dry running | Tolerated for short periods, avoid long dry running | Seal and impeller damage quickly |
| Self-priming | Yes, can draw liquid from below the pump | Needs priming and has poor suction lift |
| Solids, slurry, viscous liquid | Handles them well within the solids size limit | Efficiency falls with viscosity, and abrasives wear it |
| Flow pattern | Pulsating, a dampener can smooth it | Smooth and continuous |
| Energy use | Higher, because compressed air is costly to make | Lower on clean, steady duty |
| Flow capacity | Low to medium | High |
| Best fit | Chemical transfer, sludge, filter press feed, sumps | High-volume clean or thin liquid |
Values are typical figures from pump-maker and engineering guides. For a motor-driven option that also self-primes, see our self-priming open impeller pump. Always confirm against the datasheet of the exact model.
Key Benefits
Built for liquids that damage or clog ordinary pumps.
- No electric motor at the pump, which helps in wet areas and where sparks must be avoided
- Handles corrosive, abrasive, viscous and solids-laden liquids with the right materials
- Self-priming, so it can sit above the tank and draw liquid up
- Can be deadheaded against a closed valve without damage, as reported by pump makers
- Flow adjusts by air pressure or a discharge valve, with no inverter needed
- Local engineering and after-sales support from Techno Bangla
Is an AODD Pump Right for Your Plant?
Choose an AODD Pump When
- The liquid is corrosive, abrasive, viscous or carries solids
- You move acid, caustic, solvent or sludge between tanks
- The pump must self-prime or may run dry at times
- Flow is low to medium and a pulsating flow is acceptable
- Your plant already has a compressed air supply
Choose Another Pump When
- You need high, steady flow of clean liquid. Use a centrifugal pump
- You need accurate small feed rates. Use a metering dosing pump
- You have no compressor and air would be costly to add
- Noise is a problem and you cannot fit a muffler
- The pump can sit in the tank. See our submersible sewage pump
Where AODD Pumps Are Used
Any plant that moves aggressive or solids-laden liquid in batches.
- Acid and Caustic Transfer
- Solvent Transfer
- ETP Sludge Transfer
- Filter Press Feed
- Sump and Pit Emptying
- Textile and Dyeing Chemicals
- Food Processing
- Tank Clean-Out
How to Choose the Right AODD Pump
Share these details with our engineers and we will recommend a suitable model and size.
- Liquid and concentration. This decides body and diaphragm material. Never put acid or caustic through an aluminium body.
- Flow and discharge pressure. Discharge pressure cannot exceed air supply pressure. Pumps in this class often list about 7 bar (roughly 100 psi) maximum air.
- Solids size and abrasion. Check the maximum particle size on the datasheet. Sludge and filter press feed need wear-resistant parts.
- Compressed air supply. Catalogues of this class list maximum air use from about 0.3 to 1.5 m³/min by size. Size your compressor to match, and ask about air filter, regulator and drain for humid Bangladesh conditions.
- Suction lift, pulsation and noise. Catalogues list suction lift of roughly 5 to 7 m, and less with thick liquid. Add a pulsation dampener on long pipes and a muffler on the exhaust.
AODD Pumps for ETP Sludge and Filter Press Feed
Wastewater sludge can be thin or thick, often holds only a few percent solids by weight, and wears ordinary pumps. AODD pumps are widely used to transfer it and to feed filter presses, because they tolerate solids and variable flow.
A filter press needs rising pressure as the chambers fill, so confirm the discharge pressure with us first. See our filter press and screw press pages.
Installation and After-Sales Support
Techno Bangla Creation supplies treatment plant equipment together with installation, commissioning and after-sales support for factories, businesses and organizations across Bangladesh.
Textile dyeing is a red-category industry in Bangladesh and must run an ETP, so pumps that move its chemicals and sludge must keep working. See our ETP plant page, and send your liquid and flow for a recommendation.
Frequently Asked Questions
What is an air operated diaphragm pump?
An air operated diaphragm pump (AODD pump) is a positive displacement pump driven by compressed air instead of an electric motor. Air pushes two flexible diaphragms back and forth on a shared shaft, drawing liquid in and forcing it out. It moves acids, solvents, sludge and other difficult liquids.
What is the difference between an AODD pump and a centrifugal pump?
An AODD pump moves a fixed volume per stroke, self-primes, tolerates short dry running and handles solids, but gives pulsating flow and uses costly compressed air. A centrifugal pump gives smooth, high flow at lower energy cost on clean liquid, but needs priming and cannot run dry.
Is an AODD pump the same as a dosing pump?
No. An AODD pump is a general transfer pump for moving liquid between tanks, while motor-driven metering pumps are used for accurate dosing. Pulsating, air-driven flow makes an AODD pump a weak choice for precise feed rates. See our chemical dosing pump page for that duty.
Which material should I choose for an AODD pump?
Match material to your liquid. PP or PVDF bodies with a PTFE diaphragm suit acids and alkalis, stainless steel suits food and mild chemicals, and aluminium suits neutral liquids but not acids or caustic. Check your liquid and concentration on a compatibility chart before you order.
Can an AODD pump run dry?
Pump makers report that AODD pumps tolerate dry running better than centrifugal pumps, because the liquid does not cool or lubricate the air side. Long dry running still wears parts and wastes compressed air, so avoid it and confirm the limits on the datasheet of the exact model.
Is an AODD pump suitable for ETP sludge and filter press feed?
Yes, AODD pumps are widely used to transfer wastewater sludge and to feed filter presses, because they tolerate solids and variable flow. Check the maximum particle size, wear-resistant parts and the pressure your filter press needs at the end of each fill. Our engineers review this during selection.
How much does it cost to run an AODD pump?
An AODD pump uses no electricity but needs a steady compressed-air supply, and air is the main running cost. Making compressed air is generally less efficient than electric drive, so a centrifugal pump costs less on clean, high-volume duty. Check the air use on the datasheet and size your compressor to match.
How can I get a quotation for an air operated diaphragm pump?
Send your liquid, required flow, discharge pressure and available compressed air to our engineers by phone or email. We reply with a free quotation for your ETP, WTP, STP or water treatment equipment.
