How to Solve for Crystallization in a Pump

Under certain conditions, a liquid solution will begin to crystallize, or form solid crystals. This typically occurs under the right combination of environmental conditions and other factors, such as vibration. Users are running into crystallizing fluids more frequently in the lab environment, which makes it difficult to process via conventional equipment. That is why it’s important to have a pump that can handle these crystallizing fluids.

Why You Need a Pump to Handle Crystallizing Fluids

In addition to applications where crystallizing fluids are required, users have been increasingly challenged encountering fluids that crystalize. Today, users are largely using buffer solutions in their equipment to maintain a stable pH value of the fluid being mixed in with the buffer.

However, if crystallization were to occur within the pump, it could lead to the pump stalling, leaking or breaking. What is the solution to this problem? To solve this, we need to examine why fluids crystallize in a pump.

Why Do Fluids Crystallize?

While temperature and/or contact from another element can cause fluids to crystallize, pump material, pressure, and the reaction to variables including the air outside of the pump can all contribute to crystallization. Air specifically has a tendency to dry out fluids and help accelerate crystallization. As a result, crystals can stick to the ceramic piston.

Crystallizing fluids are particularly common in dialysis instruments that have to process heavily concentrated dialysate, which tends to crystallize very easily. Saline or salt solutions are also more prone to crystallizing.

In the event of a fluid crystallizing, the pump can seize. This can create a whole slew of issues with the pump, not to mention, lost productivity time while the pump is being serviced.

How Do You Solve for Crystalizing Fluids?

Fluid Metering has developed some effective solutions for resolving problems caused by crystallizing fluids. These include:

• A secondary set of pump ports: Users can flush a solid fluid through by either gravity feeding or pressure feeding it through the second set of ports. These ports create a liquid barrier between the crystal-forming chemical and air so that air exposure does not happen.
• Treating the surface of the piston with a special coating: This makes the surface of the piston hydrophobic, which doesn't allow crystals to stick to the surface of the piston. Adding this coating prevents the pump from stalling. Making the piston hydrophobic is a much simpler way for customers to solve the crystallization problem.
• Custom seal and ceramic configurations: The engineers at Fluid Metering have spent countless hours designing and testing pumps with specialized seals and ceramics. These customized configurations have a proven success rate for mitigating seepage and eliminating crystallization.

Fluid Metering has a number of products that can be equipped with flush ports to help reduce crystallization, including the following:

• Q1CKC Pump Head
• Q1CSC Pump Head
• Q1CTC Pump Head
• Q2CKC Pump Head
• Q2CSC Pump Head
• Q2CTC Pump Head
• Q3CKC Pump Head
• Q3CSC Pump Head
• Q3CTC Pump Head
• RH Motorless Miniature OEM Pump

If you’re regularly having this problem with your instruments, rather than performing your own trial and error, we suggest getting in touch with one of our experts at Fluid Metering. We can help troubleshoot issues you’re having and recommend any fixes (including but not limited to the ones we’ve noted above).

Keep in mind that while the solutions listed above are viable ones, we’re also working to improve the process and continue to develop methods to prevent crystallizing.

Questions to Ask When Searching Pumps for Crystallizing Fluids

Do you have a pump that handles air sensitive or crystal-forming fluids?

As we noted above, some of the simple fixes include installing a secondary set of pump ports, treating the surface of the piston with a special coating, and/or customizing a seal and ceramic configuration to dampen crystallization.

Can the pump handle my requirements?

For more information on some of the problems that crystallization may cause, how to resolve them, and how to acquire the pump that meets your specific fluid needs, contact the experts at Fluid Metering today.