Blog posts tagged with 'pump'

Air-operated double diaphragm (AODD) pumps are highly versatile, reliable devices widely used across various industries for handling viscous, abrasive, and shear-sensitive fluids. Powered by compressed air, these pumps use two diaphragms in a reciprocating motion to transfer liquid. With no need for electricity, these pumps offer a versatile option for hazardous and demanding environments.

AODDs: Basic Parts and Operation

1. Diaphragms: Located on either side of the pump, the diaphragms are flexible membranes typically made of materials like PTFE or rubber. 
2. Air Chamber: The air chamber (also known as the air valve chamber) is where compressed air is introduced to alternate between the two diaphragms. 
3. Inlet and Outlet Manifolds: The inlet manifold allows the fluid to enter the pump chamber, while the outlet manifold directs the fluid out of the pump after it has been moved by the diaphragms. 
4. Check Valves: Each diaphragm chamber has two check valves, one at the inlet and one at the outlet. These valves are responsible for directing fluid flow in a single direction. Typically a ball and seat style check valve.  
5. Valve Assembly (Air Valve): The air valve assembly, typically located in the center section of the pump, controls the distribution of compressed air to the diaphragms. 
6. Fluid Chambers: Fluid chambers are located on either side of the diaphragms. 
7. Exhaust Port: As compressed air pushes one diaphragm, the air on the opposite side is expelled through the exhaust port. This port vents the air used to move the diaphragms, and in some applications, exhaust air is collected or muffled to reduce noise.
8. Center Section: This is the core of the pump, housing the air valve and the air distribution system. 

 

 

How These Parts Work Together

When the pump starts, compressed air is directed into the air chamber behind one of the diaphragms, causing it to push outward and transfer fluid out through the outlet manifold. Simultaneously, the opposite diaphragm is pulled inward, creating suction in its fluid chamber, drawing in new fluid through the inlet manifold. The air valve then alternates the air supply to the other diaphragm, repeating the process. This alternating motion allows AODD pumps to handle viscous, abrasive, and shear-sensitive materials efficiently and reliably.

 

 

This design makes AODD pumps ideal for industries where the safe handling of various fluid types—especially in explosive or corrosive environments—is essential. 

 

Advantages of an AODD Pump

1. Corrosion Resistance

Advantage: Built with materials like PTFE, Viton, and Santoprene, AODD pumps can handle a wide variety of fluids, including those that are abrasive, viscous, corrosive, or contain solids.

Benefit: This versatility allows them to be used in many different industries and applications, from chemical processing to food and beverage production.

2. Self-Priming Capability

Advantage: AODD pumps are self-priming, meaning they can start pumping without needing to be filled with fluid first.

Benefit: This makes them ideal for applications where the fluid source is below the pump or where frequent starts and stops are required.

3. Ability to Run Dry

Advantage: AODD pumps can run dry without damage, unlike many other pump types. This means operating the pump without fluid moving through it.

Benefit: This is valuable in situations where the fluid supply may be inconsistent or may be interrupted. For example, you could use an AODD to pump out the contents of a barrel without needing to monitor the liquid level and shut off the pump immediately when the barrel is emptied to avoid damage to the pump. 

It should be noted that although an AODD pump can run dry, prolonged operation with no fluid can be hard on the diaphragms and other components. 

4. Safety 

Advantage: While not all AODD pumps are inherently explosion-proof, they are powered by compressed air and don’t require electricity, eliminating the risk of sparks.

Benefit: This generally makes them safe for use in hazardous environments where flammable or explosive materials are present, such as in the oil and gas industry. Always be sure to check that your pump and pump materials are compatible and designed for your application and environment.

5. Gentle Pumping Action

Advantage: The reciprocating diaphragm movement in AODD pumps produces a gentle, low-shear pumping action compared to other pump types. 

Benefit: This makes AODD pumps preferable for handling shear-sensitive fluids, such as emulsions, suspensions, and biological materials, without damaging them.

6. Easy Maintenance

Advantage: AODD pumps have relatively simple designs with few moving parts, making them easy to maintain and repair.

Benefit: Maintenance can typically be performed on-site without the need for specialized tools, reducing downtime.

7. Pumping of Solids and Slurries

Advantage: AODD pumps can easily handle fluids containing solids or slurries without clogging.

Benefit: This capability is crucial in industries like wastewater treatment, mining, and construction, where the fluid being pumped often contains particles or debris.

8. Simple Control

Advantage: The flow rate of AODD pumps can be easily adjusted by regulating the inlet air pressure without the need for complex controls.

Benefit: Common air regulators are all that is required to adjust the pump. A simple ball valve can be used to turn the pump on and off.

9. Suction Lift Capability

Advantage: AODD pumps can achieve significant suction lift (30 feet or more!), making them capable of drawing fluid from deep or difficult-to-access locations.

Benefit: This makes them useful in situations where the fluid source is located below the pump, such as in sump pits or underground storage tanks.

 

Specific AODD Pump Applications Across Industries

The unique design of AODD pumps allows them to fit into several different applications. Let’s examine some specific scenarios where an AODD pump can excel while other transfer pumps fall short.

Safe Transfer of Corrosive and Hazardous Fluids

In the chemical industry, AODD pumps are essential for safely transferring corrosive and hazardous substances. Their seal-less design significantly reduces the risk of leaks, enabling secure handling of acids, solvents, and aggressive chemicals.

Specific applications: AODD pumps with poly body and Teflon diaphragms can be used to pump high concentrations of phosphoric acid and Kynar body pumps with Teflon diaphragms can handle sulfuric acid. 

AODD Pumps in Food and Beverage Production

AODD pumps are widely utilized in the food and beverage sector to handle products like sauces, syrups, and beverages. Their mild pumping action preserves the quality and consistency of materials that can change in viscosity when agitated or stirred (creams, sauces, condiments, etc.).

Specific applications: There are also AODD pumps designed for handling large solids and slurries associated with the meat and poultry processing industries. These pumps are sanitary pumps designed for quick and easy cleaning. Typically featuring high-grade stainless-steel bodies.

Mining and Construction: Heavy-Duty AODD Pumps for Slurry and Dewatering

Mining and construction industries present unique and rugged applications. The need for dewatering dirty water and sludge where the contents and solids sizes are often varied and unpredictable. The right AODD pump can withstand tough environments. They are also portable and can run dry without damage, making them a reliable choice in these demanding fields.

Specific Application: Warren Rupp offers durable pumps with metal bodies (aluminum, cast iron, stainless). The Sandpiper Beast is a tough, clog-resistant pump designed to move fluids with debris up to 2 inches in diameter.

Petroleum Industry

In the oil and gas industry, AODD pumps move crude oil, gasoline, diesel, and other petroleum fluids. The pumps’ lack of electrical components provides explosion-proof safety, making them ideal for hazardous environments. 

AODDs are ideal for handling oils and hydraulic fluids of various weights making them a versatile option for fleet maintenance. 

Specific Applications: The Zeeline NS1040UL is a UL-rated AODD that will safely pump gasoline and diesel fuels up to 37 gallons per minute. 

AODD pumps also work excellent for handling waste oil. 

Car and Fleet Wash

Transferring different soaps, detergents, wax, and sealers requires a pump that can move the fluid without resulting in foaming. It also must handle a wide range of different chemical combinations and viscosities.  

Specific applications: This Yamada poly pump is versatile and has wide chemical compatibility for soaps, detergents, and other cleaning products. 

 

 

What Materials are AODD Pumps Made From?

AODD pumps are constructed from a variety of different materials. Different materials are used for the main components: the housing, check valve balls, seats, and diaphragms. 

The housing (or body) of an AODD pump consists of the fluid chambers and inlet/outlet manifolds. Common materials include:

• Aluminum: Lightweight and suitable for oils, coolants, and certain solvents but may corrode with acidic or abrasive fluids.
• Stainless Steel: Durable and resistant to corrosion, making it ideal for food, beverage, pharmaceutical, and certain chemical applications.
• Polypropylene: A cost-effective, lightweight plastic that resists a wide range of chemicals. 
• Kynar (PVDF): A chemically resistant plastic with excellent durability, often chosen for aggressive chemicals like acids and solvents.
• Cast Iron: Highly durable but susceptible to corrosion with certain chemicals. They are commonly used for demanding applications in construction and mining. 

The check valve balls are in direct contact with the fluid and must be resistant to the medium you are pumping. Common materials include:

• Santoprene: A thermoplastic elastomer with good chemical resistance, typically used for water-based fluids and certain chemicals.
• PTFE (Teflon): Highly resistant to chemicals, suitable for aggressive solvents, acids, and high-temperature applications.
• Nitrile (Buna-N): Good for petroleum and certain chemicals but less resistant to extreme temperatures.
• Viton: Excellent for high-temperature and a variety of chemical applications.

Seats create the sealing surface for the balls, and their material affects the pump’s fluid compatibility. Common seat materials:

• Polypropylene
• Stainless Steel
• Santoprene and Buna-N

Diaphragms are crucial in AODD pumps, as they directly handle fluid and pressure. The choice of diaphragm material influences chemical resistance, flexibility, and temperature tolerance.

• Santoprene: A flexible, durable option for a range of chemicals, commonly used in general applications.
• PTFE (Teflon): Excellent chemical resistance, suitable for aggressive fluids, and has a longer lifespan in abrasive applications. 
• Buna-N (Nitrile): Good for petroleum-based fluids and general applications but limited by lower chemical and temperature resistance.
• Hytrel: A thermoplastic polyester with good chemical resistance, flexibility, and durability for various industrial fluids.

 

AODD Pump Limitations

The AODD family is very versatile and offers unique benefits but there are some limitations:

Requires Continuous Air Supply

AODD pumps need a reliable, continuous supply of compressed air to function. In remote locations or applications where compressed air is not readily available, additional equipment (like air compressors) may be needed, adding to setup costs.

Efficiency and Air Consumption

AODD pumps rely on compressed air to operate, which can lead to high air consumption, especially when running at high flow rates or under heavy loads. This can increase operating costs.

Compared to other types of pumps (like centrifugal pumps), AODD pumps typically have lower energy efficiency. This can be a drawback in applications where energy efficiency is a primary concern.

If energy efficiency is a priority, Graco offers electric motor-driven double diaphragm pumps. This provides you with the benefits of an AODD with significantly lower (up to 80%) operating costs. 

Pulsing

The “back and forth” nature of the pumping operation can result in a pulsating flow. This can be mitigated with pulsation dampeners, but it may still not be ideal for applications requiring a steady, continuous flow.

Pressure

An Air-Operated Double Diaphragm (AODD) pump typically operates at a maximum pressure of around 100 psi, although certain specialty models can handle higher pressures. These pumps are generally not suitable for high-pressure applications that exceed their design limits. Most AODD pumps have a 1:1 pressure ratio, meaning the liquid discharge pressure matches the air inlet pressure. For example, if the air supply is set to 50 psi, the pump will produce a liquid discharge pressure of approximately 50 psi.

 

Ready to Choose the Right AODD Pump?

Explore our selection of Air-Operated Double Diaphragm (AODD) Pumps, tailored for a wide range of applications. Our team is ready to assist you in finding the perfect pump for your industry’s needs.

Choosing the right pump can make all the difference in how smoothly your system runs, whether moving fertilizer, de-icing fluid, or pumping out a pit. One of the big questions people often ask is: which type of pump gives you the highest flow rate?

The type of pump designed to produce the highest flow rate is a centrifugal pump. These pumps are intended to handle large volumes of liquid at relatively low pressures. They work by converting rotational kinetic energy, often from a motor, into energy in a moving fluid, which creates a flow rate that can be very high.

If you're looking to move a lot of liquid quickly, the centrifugal pump is usually your best bet. Let's take a closer look at why these pumps are so good at handling large volumes with ease.

 

 

Why Centrifugal Pumps Excel in High-Flow Rate Applications

Centrifugal pumps are engineered to move as much liquid as possible in an efficient manner, making them the go-to choice when high flow rates are needed. Other pump types are designed to handle thicker liquids or to generate higher pressures, but a centrifugal pump's primary purpose is to transfer fluids that are relatively less viscous. Think water, fuels, fertilizers, and other flowable liquids.

How Centrifugal Pumps Work

Centrifugal pumps function by converting rotational energy into fluid flow, making them exceptionally efficient for high-volume transfer. You can read more on the specifics in our centrifugal pump guide. The short explanation is the heart of a centrifugal pump is the impeller. As the impeller spins, it imparts velocity to the fluid, pushing it outward from the center where the fluid enters, to the edges where it exits. This process creates a continuous, smooth flow of liquid.

High Speed Equals High Flow

The faster the impeller spins, the more kinetic energy is transferred to the fluid, resulting in a higher flow rate. This ability to maintain a steady, high-speed transfer of liquid makes centrifugal pumps ideal for applications that demand high flow rates.

Continuous Flow for High Efficiency

Unlike positive displacement pumps-such as gear pumps or piston pumps-that move liquid in cycles, centrifugal pumps deliver a continuous, non-pulsating flow. This is a significant advantage in applications where moving large volumes of liquid is essential, as it reduces turbulence and inefficiencies that can arise from intermittent flow. Because centrifugal pumps don't need to pause between cycles, they're more efficient for handling large volumes.

Scalability

One of the key benefits of centrifugal pumps is their scalability. These pumps can easily be adjusted to handle higher flow rates by increasing the impeller size or the speed at which the pump operates. This scalability is more straightforward compared to other types of pumps, where increasing the flow rate might involve more complex changes.

High Flow at Lower Pressure

Centrifugal pumps shine in applications where high flow rates are needed at relatively low pressures. While they might not be the best choice for high-pressure needs, their design is optimized to move large amounts of liquid with minimal energy input.

 

Flow Rate Capabilities of Centrifugal Pumps

The flow rate of a centrifugal pump can vary widely depending on the size of the pump, the speed of the impeller, and the specific design of the system. These pumps can achieve flow rates ranging from a few gallons per minute (GPM) to several thousand GPM. For instance, centrifugal pumps used in large-scale agriculture can easily move hundreds of gallons in a minute. 

Common High-Flow Centrifugal Pump Applications

Railcar Unloading

Centrifugal pumps are ideal for transferring liquid fertilizer from railcars to storage tanks. In many scenarios flow rates of over 1000 gallons per minute are possible.

• View more high-flow transfer pump options

Dewatering

Centrifugal and submersible (a type of centrifugal pump) are ideal for moving water from construction sites, drainage pits, or any location where excess water accumulation could interfere with operations.

• View high-volume submersible pump options here.

Industrial Cooling

In cooling towers, the volume of water that needs to be circulated is immense. Centrifugal pumps are ideal for this purpose due to their ability to handle high flow rates. These pumps ensure a continuous and reliable flow of water through the cooling tower.

Industrial and Manufacturing Processes

Centrifugal pumps are essential for the precise and reliable transfer of raw materials, intermediates, and finished products. Additionally, when precise flow control is needed, these pumps can be paired with variable frequency drives (VFDs) to adjust the flow rate accurately.

• View industrial pump solutions

You can read this beginner guide to sizing a centrifugal pump. Also, Dultmeier engineers have several combined years of experience sizing pumps according to the specific needs of several high-volume applications. Be sure to contact us if you have any questions.

 

Factors Affecting Flow Rate

Several factors affect the flow rate of a centrifugal pump, including:

1. Pump Size: Larger pumps with bigger impellers can move more liquid per rotation, increasing the overall flow rate.
2. Impeller Design: The shape and size of the impeller blades, along with the speed at which the impeller rotates, play a crucial role in determining the pump's efficiency and flow rate.
3. System Head: The height and resistance the liquid must overcome (referred to as 'head') can impact the pump's performance. Centrifugal pumps are more efficient at lower heads, making them ideal for applications requiring high flow but not high pressure.

If you would like a more detailed explanation of system head and flow rates, be sure to read our guide on centrifugal pumps written by in-house engineer Tom Hansen.

 

Selecting the Right High-Flow Pump for Specific Applications

Although a centrifugal pump is the best pump type for high-volume transfer of several fluids, in some scenarios a centrifugal pump may not be the best option. Thicker fluids may require a gear or diaphragm pump. Applications that require high-flow and higher pressures such as hydro excavating or sewer jetting, will need a different type of pump.

Here are some common applications where a centrifugal pump may not be the best option and which pump types can offer the highest flow rate in each scenario:

Tree Spraying: While a centrifugal pump offers enough volume, spraying tall trees requires more pressure than they can deliver. This is where high-flow diaphragm pumps come into play. They can deliver flow rates ranging from a few gallons per minute to over 100 while producing pressures from 250 psi and more.

Liquid Feed Transfer: The combined viscosities and occasional cold temperatures of many liquid applications require a gear pump for high-volume transfer. Centrifugal pumps work in some scenarios but are limited when handling thicker, more viscous liquids like molasses.

Learn more in our guide on how a gear pump works.

NH3: Vane pumps are used for high-volume transfer of anhydrous ammonia. Centrifugal pumps can struggle with the low viscosity and high vapor pressure of NH3, leading to issues like cavitation, reduced efficiency, and potential pump damage.

High-Pressure: Applications requiring higher pressures (think 1000 PSI+), and large volumes of fluid typically require plunger pumps or piston pumps. Pumps producing high-pressure and high flow rates do have significant horsepower requirements.

12-Volt Power: 12-volt motor pumps are available for applications where only 12-volt power is available. The flow rates that can be achieved by these pumps are limited to a maximum of about 20-25 gallons per minute. This is only achieved at very low pressures, about 5 PSI. There are 12-volt pumps that produce 1-5 GPM at much higher pressures, typically 40-60 PSI, making them much more versatile for low-volume applications.

 

Final Thought

Centrifugal pumps are the top choice for high-flow applications, efficiently moving large volumes of low-viscosity fluids at lower pressures. Their scalability and continuous, smooth flow make them ideal for industries requiring reliable, high-volume liquid transfer.

If you need help selecting and sizing a centrifugal pump you can reach out to our team. Our engineering department can provide flow analysis and expert guidance!

Resourceful folks are always looking for ways to get the most out of their equipment. One way to do this is to repurpose tools whenever possible. One such tool is the trash pump. If you already have one and need to move fertilizer, it only makes sense to wonder, "Can I use my trash pump for fertilizer?".

The short answer is yes, in many cases, a trash pump can handle fertilizer. However, this is not always the case. Several factors affect a pump's ability to handle fertilizer, including the type of fertilizer, pump materials, horsepower, and more-all of which might impact the overall effectiveness and longevity of your trash pump.

Do not worry. In this article, we will explore not only whether repurposing a trash pump for fertilizer is a feasible option but also which situations make the most sense. We'll cover the basics of trash pumps, the properties of fertilizers, and how to know if your specific pump can handle the job.

 

What is a Trash Pump?

A trash pump is a type of centrifugal pump that is designed to move water that contains large pieces of debris, such as sand, gravel, sticks, etc. Generally, they are self-priming pumps that are constructed out of. Some are made from more durable metals like cast iron or ductile iron, while less expensive models are aluminum or other alloys.

Compared to other centrifugal pump types they are generally less efficient. This is because they are designed for versatility and not for efficiency. Most centrifugal pumps used for clear or "clean" fluids are more efficient because they have a smaller clearance between the impeller and the volute inside the pump housing.

Trash pumps have a smaller impeller diameter in relation to the volute size, which allows them to pass rocks or other debris more easily without scoring the internals of the pump. This capability makes them particularly useful in construction, agricultural, and dewatering/drainage scenarios.

 

Can Trash Pumps Handle Fertilizer?

Fertilizers come in various forms: liquid, granular, and soluble powder. Each type has different handling and application requirements. Liquid fertilizers are often preferred for their ease of application and rapid absorption by plants. However, they can be corrosive or abrasive, depending on their chemical composition, which can include nitrogen, phosphorus, potassium, and various micronutrients in different chemical forms.

The concept of using a trash pump for moving liquid fertilizer might seem viable. Trash pumps can handle slurries and fluids with solid particles, which theoretically could include liquid fertilizers. However, there are some things you need to consider, like material compatibility, efficiency, and reliability, before actually using your trash pump to transfer fertilizer.

Trash Pump Chemical Compatibility

Many trash pumps are designed to handle water and may not be compatible with the aggressive chemical nature of some fertilizers. Corrosion of the internal components, such as the impeller and the housing, can occur if the materials are not resistant to fertilizer chemicals.

Materials Typically Not Suited for Common Liquid Fertilizers:

• Aluminum
• Brass
• Polycarbonate
• PVC

Materials Recommended for Use with Liquid Fertilizer:

• Cast Iron
• Stainless Steel
• Viton
• Carbon Steel
• Polypropylene

In addition to pitting, rust, and corrosion of the housing and impeller, the pump seal can suffer damage from an aggressive fertilizer. Trash pumps typically have a mechanical shaft seal that keeps liquid from leaking out during operation. This seal consists of two faces and an elastomer that rub together to form a barrier.

If the seal faces or elastomers are made from a material not compatible with the type of fertilizer you want to pump, the seal will fail. Abrasive fertilizers cause damage to the seal faces and the pump will leak around the shaft. This can happen gradually or quite quickly if the fertilizer and materials are not compatible.

A fertilizer's with your pump materials might be the most crucial deciding factor for whether you can utilize a trash pump over another type of pump . If you are new to fertilizer transfer pumps, this guide explains in detail the different options for high-volume fertilizer transfer pumps.

Trash Pump Efficiency

Let's say your trash pump is constructed of materials that will stand up relatively well to whatever type of fertilizer you need to pump. Good, you can check off that consideration. However, there is still the matter of efficiency to consider. Trash pumps are by nature less efficient than other centrifugal pumps typically used for fertilizer transfer. You'll therefore want to ensure that your trash pump will actually perform as you need or you'll have to start at square one finding another solution.

As mentioned earlier, trash pumps generally have more clearance inside them to pass solid material. This makes them less efficient. (If you want to fully understand centrifugal pump efficiency, then check our  You may be able to live with this lower efficiency, especially if it means not having to spend the extra money buying another more expensive pump.

Even so, just because a trash pump may work, doesn't mean it will move the liquid at the same volume as other pumps designed specifically for the transfer of fertilizers. It's crucial then, that the prospective costs of that lower efficiency be weighed out for both the short-term and long-term benefits of your operation.

 

Conclusion: Should You Use a Trash Pump for Fertilizer?

While trash pumps are a versatile option in a pinch, there are better pumps available for the efficient transfer of fertilizer. Over a season the additional amount of time it takes you to move fertilizer could impact your bottom line. Not to mention trash pump built with metals not suited for your specific fertilizer could fail prematurely, costing you additional time and money than if you had opted for another pumping solution in the first place.

Dultmeier carries several different pump lines that are well-equipped for fertilizer transfer:

• Engine-Driven Fertilizer Pumps
• Electric Motor Driven Fertilizer Pumps
• Stainless Steel Pumps

For more details on which fertilizer pump will work best for you, check out our guide on the best fertilizer pump options