Not all pumps are created equal. While pumps are found everywhere from swimming pools to chemical vats to fuel depots, each application can have its own unique challenges. When selecting a pump, here are a few factors you will want to consider, according to the U.S. Department of Energy:
- Fluid: Chemicals and fuels can destroy pumps that aren’t built for the task. Choose a pump that’s designed to handle the corrosiveness and consistency of the fluid so that it doesn’t get degraded or clogged from slurry or debris. Similarly, know the viscosity of the fluid to ensure the pump has enough power to draw the liquid through.
- Flow rate: Calculate your desired flow rate by multiplying the total volume by the time in which you want to move the liquid. For example, for a 500-gallon pond that needs full circulation once an hour, you would want to select a pump with a minimum rated flow rate of 500 GPH (gallon per hour).
- Operating temperature: While pumps can operate at a wide range of temperatures, if you are working with liquids that are hotter than 200°F, check that the pump is rated for the maximum temperature of the liquid you’ll be pumping.
- Vapor pressure: To minimize the risk of cavitation, ensure the pump is rated for your fluid's vapor pressure, which is the force per unit area that a fluid exerts when changing from a liquid to a vapor.
Choosing Between Different Types of Pumps
Once you know the material your pump will need to handle and the capabilities your pump requires, you can begin comparing your different pump options. Here are the common pump types and mechanisms you’ll see on the market:
- Centrifugal pumps: A centrifugal pump can provide the constant flow of a large quantity of fluid at high speed by using one or more impellers such as a paddle wheel or propeller to draw the fluid in. As one of the most common pump mechanisms, it can be used to pump all sorts of low viscosity liquids, including those containing solid elements such as wastewater. Centrifugal pumps are used across a wide variety of industries, including agriculture, water utilities, industrial, power generation, petroleum, mining and more.
- Diaphragm pumps: Also known as a membrane pump, a diaphragm pump is a mechanism that involves the reciprocating action of a set of diaphragms to move the fluid. As fluid enters one chamber, it forces out fluid from the other chamber in a cycle. Because there are no moving parts within the diaphragm chambers themselves, these pumps are useful for pumping liquids with high solid content or high viscosity, such as chemicals, paints or syrups.
- Circulating pumps: Rather than moving liquid from one place to another, a circulating pump is used to circulate fluids within a specific system. Circulating pumps are commonly used in water heating systems to ensure the hot water is equally distributed with incoming cold water to maintain a constant temperature. A circulating pump is also useful for moving water throughout a pond for oxygenating the water or for ensuring chemicals that are mixed into a container get evenly distributed.
- Fuel and oil transfer pumps: These pumps are designed for the unique challenges of moving oil, fuel and other substances from one container to another, such as transferring fuel from a tank into heavy equipment. Oil transfer pumps are designed for high viscosity fluids and are engineered for higher flow rates and rugged use.
- Chemical pumps: Chemical pumps are specifically designed to be used for the development, usage and disposal of chemicals. They are made out of materials that can stand up to corrosion, such as stainless steel, titanium, rubber, plastic and glass. Because different chemicals have different corrosive effects on materials, make sure you use a pump designed specifically for the chemical you wish to pump.
- Drum pumps: These pumps are built to help you suction out fluids from drums, barrels, pails and totes so that you can minimize the risk of spills from pouring the container or for drawing fluids out of a container that is too heavy to lift. Electric-powered pumps are useful for tasks that require high volume transfer, while hand-powered pumps are useful for low-volume or remote pumping applications where electricity isn’t available. If you need higher flow rates than a hand-powered pump, and more precise flow control than an electric drum pump, without electricity, then a pneumatic pump that uses a compressed air supply is a good option.
Now that you know more about which pump to choose for the job, you can pick the right one for your facility.