No other sector of the processing industry has higher requirements on the components of its systems than pharma and food production. Here, the focus is uncompromisingly on the product, where hygiene and safe and reliable handling are crucial in the production of food, beverages, pharmaceuticals and active substances. Selecting the correct pump technology is therefore not an easy task. But these challenges can be overcome by knowing the key characteristics of the products and relying on experienced manufacturers who are open to new technologies.
In pharmaceuticals and food, the focus is not on systems and components, but on the products. Producing them safely, reliably and in accordance with all quality requirements is the top priority – the production system is nothing more than a means to an end.
This perspective is also crucial for the pump technology used: In the end, whether a pump has an excellent delivery rate or energy efficiency is not the only deciding factor. It is also crucial whether the pump technology is suitable for the application at hand.
Experience and technological variety win
Owners of production equipment consequently want their suppliers to have industry know-how and offer a variety of different technologies. NETZSCH offers both: The pump manufacturer has decades of experience in the pharmaceutical industry and food and beverage production. This allows the company to offer a large number of displacement pump technologies, each covering a wide range of applications while offering specific benefits for individual tasks:
- Progressing cavity pumps
- Multi screw pumps
- Rotary lobe pumps
- Peristaltic pumps
Progressing cavity pumps: experts for media with large solids
Progressing cavity pumps are often the first choice when it comes to difficult media, because they are exceedingly tolerant: They pump liquids with low or high viscosity at a delivery rate of up to 120 m³/h. Even lubricating media or a high content of gas and/ or solids are handled with ease. As substances pumped in food or pharma production often have exactly these characteristics, progressing cavity pumps are predestined for these industries.
The key to their flexibility lies in the function principle: The liquids are conveyed by a rotor which rotates and oscillates in a stator. The rotor is made of a hard material – usually stainless steel – while the stator is elastic. This means that even abrasive media cause only little wear on progressing cavity pumps. The screw geometry of the two components creates conveying chambers for transporting the medium. The delivery volume is determined only by the rotational speed, which is typical for displacement pumps, and can therefore be controlled with great precision. In contrast to other displacement pumps, however, progressing cavity pump technology also features continuous, lowpulsation pumping – an advantage for particularly sensitive liquids.
Multi screw pumps: specialists for high speeds
Progressing cavity pumps and multi screw pumps have some things in common: Both pump technologies continuously and evenly move the medium through conveying chambers for gentle transport from the intake side to the delivery side. The conveying chambers in multi screw pumps are usually a little smaller, though – a difference to be considered where media with sensitive solids have to be pumped.
Multi screw pumps are a type of gear pump with helical gears: During operation, the intermeshing of the two counter-rotating spindles in combination with the pump housing forms volumetric chambers. These fill up with the pumped medium, which moves axially in these conveying chambers from the intake side of the pump to the delivery side.
Cleaning is easy under CIP conditions. NOTOS multi screw pumps from NETZSCH even have SIP capability and can be cleaned with steam.
Rotary lobe pumps: perfect for tight spaces
Rotary lobe pumps are the reliable workhorses among the displacement pumps in hygiene design: They are robust, very powerful and offer impressive speeds while still being compact. TORNADO hygiene rotary lobe pumps from NETZSCH can easily handle flow rates of up to 150 m³/h.
The rotors have two or three lobe rotors and intermesh while rotating. This action takes in the medium and transports it to the outlet of the pump. The standard versions of the NETZSCH pumps are equipped with metal rotors that seal almost completely when not in motion.
While many properties of rotary lobe pumps are comparable to those of the technologies already presented, their compact size makes all the difference for some applications: In particular in brownfield environments, i.e. systems that are already in operation and are being expanded for modernization or to improve capacity, the available space plays a crucial role. This is where the compact rotary lobe pumps offer additional advantages in addition to their high power density and reliability.
Peristaltic pumps: gentle pumping and exact dosing
Peristaltic pumps – also known as peristaltic hose pumps – are the exotic version of a displacement pump, because their technology differs significantly from other types: A rotor with rollers compresses a hose running through the pump housing, moving the medium in the hose. This design has various benefits: As no valves or seals are required, the hose itself is the only wear part.
In the recently launched PERIPRO peristaltic pumps from NETZSCH, the hose can be cleaned easily in the hygiene version with CIP capability while the pump remains installed. The housing is fitted with a window that can be opened for accessing the pump chamber. The roller that compresses the hose can then simply be swiveled out, allowing the hose to decompress. The CIP cleaning solution can then flow through the hose unhindered and flush it. The peristaltic pump does not have to be running during the CIP procedure.
As peristaltic pumps can be run dry any number of times without sustaining damage, they are also suitable for applications where dry running cannot be prevented, for example when draining barrels. With their high intake power of up to 9 m, the PERIPRO from NETZSCH is in the same league as NEMO progressing cavity pumps – but it can pull ahead with its dry running capabilities for specific applications.
The right pump for any application
Excellent results can be ensured only if the application at hand can be combined with the right pump technology while taking all challenges and requests into account. Owners of production systems should therefore choose suppliers who offer a wide range of pump technologies and have accurate knowledge of which pump design is best for which application. Manufacturers of pharmaceutical products, food and beverages can rely on this extensive know-how and the variety of different technologies at NETZSCH and therefore always receive the right pump for their specific application.