Handling corrosive fluids is a common but critical challenge in the chemical processing industry. Whether it's acids, solvents, or aggressive cleaning agents, the materials used in fluid transfer systems must be durable, resistant to chemical damage, and safe for long-term use. One of the most trusted solutions in such environments is the pneumatic diaphragm pump.
These pumps are widely used in chemical plants due to their simplicity, reliability, and ability to handle fluids that might destroy or clog other types of pumps. In this article, we'll look at how these pumps help manage hazardous and corrosive liquids in a safe and effective way.
Chemical plants deal with a wide variety of aggressive fluids daily. These can include sulphuric acid, hydrochloric acid, sodium hydroxide, and other harsh substances. Transporting such fluids requires equipment that resists corrosion and can operate safely even under difficult conditions.
Failures in fluid handling systems can lead to:
• Equipment damage
• Downtime and lost production
• Safety risks to workers
• Costly environmental spills
This is why choosing the right type of pump — and material — matters so much in this sector.
A diaphragm pump is a type of positive displacement pump that moves fluid by using a flexible diaphragm. It works by creating a vacuum that draws fluid in, then pushes it out through the outlet valve as the diaphragm moves back and forth.
Among the various options, AODD pumps stand out for their ability to run without electricity and their compatibility with many chemical types. This makes them especially useful in hazardous areas where electrical equipment may be unsuitable.
In an air operated diaphragm pump, compressed air drives the movement of two diaphragms back and forth. This motion creates suction and discharge actions that move the liquid through the pump.
Because the moving parts do not come into direct contact with the fluid — and because the pump chamber can be made from chemically resistant materials like polypropylene — the system handles aggressive chemicals well.
This design also means fewer seals and moving components are exposed to wear, reducing the risk of leaks or failures.
There are several reasons why chemical processors and plant managers choose these pumps:
1. Chemical Compatibility
These pumps can be made from materials that resist a wide range of chemicals, including highly acidic or caustic fluids.
2. No Electricity Needed
Being air-powered, they can be used safely in explosive or flammable environments, reducing electrical hazards.
3. Dry Running Tolerance
Air diaphragm pumps can run dry without damage — a useful feature when dealing with inconsistent fluid supply or during line cleaning.
4. Self-Priming Capability
They are capable of lifting fluids from a lower level, even when the inlet is dry.
5. Controlled Flow Rates
By adjusting air pressure, operators can fine-tune the output flow to match process needs.
When unsuitable equipment is used in chemical environments, several problems can arise:
• Corrosion of metal parts, leading to leaks
• Blocked or clogged pump mechanisms
• Poor flow control and inconsistent dosing
• Frequent maintenance and unexpected downtime
Working with reliable diaphragm pump manufacturers can help avoid these issues by offering pump models tailored for specific chemical types and plant layouts.
While both electric diaphragm pumps and air operated models are used in chemical settings, the choice depends on:
• The nature of the chemical
• The operating environment (hazardous or not)
• Power supply availability
• Desired control over flow and pressure
Electric versions may be better suited for steady, low-maintenance indoor operations. Air-powered pumps, on the other hand, are ideal for flexible, mobile, or hazardous environments.
Although diaphragm pumps are generally low-maintenance, there are a few best practices to keep them running safely:
• Choose the right material for the pump diaphragm based on the chemicals used
• Regularly inspect for signs of wear, especially in the diaphragm and valves
• Monitor for leaks or pressure changes that could indicate a developing fault
• Use proper air pressure to avoid overworking the pump
As always, refer to your manufacturer’s guidance for compatibility and maintenance intervals — especially if you're handling particularly aggressive fluids.
Chemical plants require durable, safe, and efficient solutions for moving corrosive liquids. The air operated diaphragm pump provides a versatile and reliable option for fluid transfer, especially in harsh or explosive environments. Its ability to work without electricity, handle a wide range of chemicals, and operate with minimal wear makes it a preferred choice across the industry.
While there’s no one-size-fits-all solution, understanding how these pumps work and where they shine can help you make informed decisions when dealing with fluid handling challenges in chemical processing environments.
Can a diaphragm pump handle strong acids or caustic liquids?
Yes, but it depends on the materials used in the pump. Many models are designed with chemical-resistant diaphragms and bodies specifically for these applications.
Do air operated diaphragm pumps need electricity?
No, they are powered by compressed air, making them suitable for use in hazardous or flammable environments.
How long does a diaphragm last in chemical applications?
It varies depending on the fluid type, pressure, and usage frequency. Regular inspection helps extend lifespan and prevent downtime.
What is the difference between a pump diaphragm and a valve?
The diaphragm moves to create suction and pressure, while valves control the direction of fluid flow through the pump.
Are diaphragm pumps hard to maintain in a chemical plant?
Not particularly. They have fewer moving parts and are often easier to clean or service compared to more complex pump systems.