Air Operated Double Diaphragm (AODD) pumps play an invaluable role in many stages of chemical production and processing. From the intake of chemical components from tanks through to transporting processed products to the point of distribution, fluid transfer is an essential part of everyday operations in the chemical industry. Whether transferring benign or hazardous material, diaphragm pumps move chemicals safely and efficiently to minimize production downtime.
A type of positive displacement pump, AODD pumps move fluid by trapping a fixed amount of that fluid and forcing or "displacing" it into the discharge pipe. Using diaphragms and check valves, the liquid chambers are filled and emptied by fluid that is drawn through a common inlet and discharged through a single outlet. Employing compressed air as its power source, an AODD pump shifts the air from one chamber to the other by a linked shaft. This motion forces liquid out of one chamber and into the discharge piping while the other chamber simultaneously fills with liquid. Here are four benefits of using AODD pumps in the chemical industry:
1. Versatility
AODD pumps are renowned for their versatility and are used widely within chemical industry operations. The composition and viscosity of fluids vary greatly and they display a range of different characteristics. AODD pumps can cope with even the most aggressive or abrasive fluids with ease.
Pumps are available in a wide range of different materials, allowing them to pump virtually any chemical on the market. The materials used to construct the pump are configured to accommodate a particular chemical’s properties.
Diaphragm pumps are also able to efficiently pump fluids with a high solid content, including those with solids up to 3 inches in diameter, such as sludge and slurry. As a rule of thumb, if it pours, it pumps!
2. Flow rate
The flow rate of an AODD pump can be easily adjusted by the diameter and stroke length of the diaphragms used. The desired flow rate and potential pressure conditions will determine the size of the pump required. Manufacturers offer a range of flexible sizes, enabling users to buy a pump that will provide the appropriate system. Another benefit of AODD pumps is that users are able to control the pump’s pressure discharge.
If a compressed air supply is available, an AODD pump can be installed wherever it is required and switched to other operations with ease. It is also possible for an AODD pump to run dry without damaging its internal mechanisms.
3. Safety
AODD pumps are seen by many as the safest design for pumping a range of liquids, including more aggressive chemicals. Fluids transferred by AODD pumps are often hazardous. It is, therefore, vital to choose the correct pump to maintain safety and environmental standards within an organization.
AODD pumps do not require electricity or any fuel other than compressed air. This intrinsically safe design means that no harmful fumes are exhausted, thus eliminating production line risks. Furthermore, they are fully sealed units, meaning they are leak proof, which makes them ideal for handling potentially hazardous fluids. Similarly, they can be partially or completely submerged in a liquid with minimal risk of contamination.
4. Simplicity
AODD pumps are constructed using a simple design, which employs minimal moving parts. Fewer parts ensure any maintenance requirements can be completed quickly. Similarly, a simple construction mitigates the risk of mechanical problems occurring in the first place. Easy to install, once connected to a compressed air line, AODD pumps are ready to use immediately.
AODD pumps do not use oil or other lubricants, which eliminates operational issues due to lack of lubrication. When compared with other, more complex types of pump, AODDs are easy to disassemble, repair, clean and maintain. This simplicity ensures the production line continues to run smoothly. Decreasing maintenance time by employing simple AODDs ensures that daily operations continue on schedule.
David Rozee is the managing director of Triark Pumps. Triark Pumps (formerly Tri-Ark Limited) is a leading distributor of diaphragm pumps, spares and accessories serving the U.K. and the rest of the world. Triark Pumps is also a member of the British Pump Manufacturers’ Association Limited
(BPMA).