Pumps in the food and beverage industry must comply with strict standards to ensure the integrity of the product being pumped. To ensure you select the ideal food-grade pump, it is critical you consider the following: flow rate, product characteristics, construction materials and any approval requirements.
Flow rate
Flow rate is defined as the volume of liquid that travels through the pump in a given time, commonly litres per minute or per hour. Selecting the correct pump involves matching the flow and pressure rating of a pump with the flow rate and pressure required for your process. Therefore, understanding your site’s requirements are critical.
Characteristics of the product:
Viscosity
Viscosity is how thick or runny your product is. This characteristic must be considered when selecting your pump and determining the process system’s friction loss. We describe the importance of viscosity in another blog by our team.
If your product is highly viscous, Global Pumps recommend a positive displacement umps. These are specifically designed to handle viscous fluids, operate at low speeds and transfer lower amounts of shear energy to the fluid in comparison to other forms of pump technology.
Alternatively, if your product has low viscous characteristics, centrifugal pumps are suitable. Centrifugal pumps generate high liquid shear, and therefore should only be used with low viscous liquids.
Abrasion
An abrasive liquid is one that can cause increased wear to your pump either by eroding surfaces through physical force. The viscosity of this abrasive fluid can play a role in determining the degree of the wear on the pump. Therefore, it’s important you consider both abrasive and the viscous characteristics of your fluid in tandem.
Although abrasive fluids are not as common in food and beverage applications, it should still be discussed. Therefore, consider the nature of your product and discuss the possibility of wear within the pump you select.
Material shear
Shear sensitive products are those materials that alter their properties when ‘worked’. These are also referred to as non-Newtonian liquids, and change in viscosity depending on the shear rate applied. An example of these liquids would be tomato sauce or mayonnaise. Newtonian liquids are the opposite and hold their viscosity regardless of the shear rate.
If you are pumping these shear sensitive products, it is critical that you select a pump that offers gentle pumping action. Diaphragm and peristaltic hose pumps are a popular choice for shear-sensitive products. Centrifugal pumps are not suitable and will shear the product, ruining its integrity.
Construction materials
One of the most critical pump characteristics to consider is the pump materials. If these are not compatible with the ingredients being pumped, you may experience pump failure, downtime and/or expensive repairs. Sanitary pumps are normally construction in stainless steel and offer operators safe and hygienic transferring.
An important thing that is often overlooked are the chemicals being used for cleaning. Besides the product itself, the pump’s construction and elastomers need to be compatible with the facility’s cleaning solutions and clean-in-place (CIP) requirements. Faults can occur when the pump elastomer or seal, and pump itself, is compatible with the food ingredient but cannot cope with the caustics used to clean the pumping system. If the facility does not use caustics and instead uses steam-in-place cleaning methods, then the pump must be able to handle the extreme temperatures that run through.
Kecol Pumping Systems Ltd is the UK leader in the design & manufacture of stainless steel & hygienic piston pumps and pumping systems. Our food transfer pumps and paste transfer pumps are designed for high viscosity products for use with 200 litre drums, IBC’s, process vessels, planetary mixing vessels and similar containers.
As an ISO9001 certified company, our aim is to consistently provide the very highest standard of products, service, advice and support to every customer, every time. https://www.kecol.co.uk/
