Translating Customer Needs into Membrane Properties
A Focus on Dairy and Protein Ultrafiltration
Key takeaways from the webinar
How can membrane technology be optimized for dairy protein ultrafiltration? The answer lies in translating process requirements into the right combination of membrane properties, separation performance, and operating conditions.
In this webinar, MANN+HUMMEL Water & Membrane Solutions explored how membrane design can address key customer needs in dairy processing, including filtration capacity, protein retention, fouling, and cleaning efficiency.
The session covered the development of a new 10 kDa ultrafiltration membrane, the different performance characteristics of two 5 kDa membranes, and a new high-retention 3 kDa membrane.
Discover the main technical insights and test results from the session below.
1. Filtration and cleaning performance are closely connected
Filtration conditions influence both fouling and cleaning efficiency. Lower fouling during product filtration can shorten cleaning cycles, while excessively long filtration times can lead to stronger fouling.
Choosing suitable process conditions and ensuring sufficient flushing between cleaning steps are therefore important considerations when optimizing membrane operation.
2. A new 10 kDa membrane targets higher filtration capacity
For dairy ultrafiltration, 10 kDa membranes are commonly selected when capacity and throughput are key requirements.
The webinar presented the development of a new 10 kDa membrane designed to deliver higher flux at comparable retention. The membrane uses the same PES material as the existing design, while its reduced thickness increases the membrane area available within an element.
The membrane thickness was reduced from approximately 230 µm to 180 µm, a reduction of around 20%. The development also focused on maintaining mechanical strength and improving membrane morphology to support process stability and cleanability.
What did tests show?
Initial results from transferring the new membrane to a 6.4-inch spiral-wound element showed:
- 35–40% higher capacity compared with a competitor's reference element.
- 25% higher capacity compared with the previous element.
An estimated 13% capacity contribution from increased membrane area and a further 12% from the membrane properties, compared with the previous design.
*These results refer to the specific element configurations and test conditions presented during the webinar; they should not be interpreted as guaranteed improvements in every installation.
3. Two 5 kDa membranes address different customer priorities
A lower molecular weight cut-off does not automatically make one membrane the best choice for every application. The appropriate solution depends on whether the priority is protein retention or filtration capacity.
The webinar compared two 5 kDa membranes: UP005 and 5 kUF.
- UP005: Designed for high retention, including high retention of a 3 kDa test substance. It is particularly relevant when minimizing protein losses is a priority.
- 5kUF: Demonstrated higher flux in the presented field tests, making it relevant when filtration capacity is a key consideration.
In whey protein concentration field tests, UP005 showed approximately 50% lower whey protein transmission than 5kUF. Conversely, 5kUF achieved 20-30% higher flux than UP005 in the tests presented.
These results illustrate the trade-off between retention and throughput and why membrane selection should reflect the specific project objective.
4. A new 3kDa membrane with focus on high retention
For applications that require stronger retention, the webinar also presented a new 3kDa membrane.
In laboratory comparisons using a 3 kDa test substance, the new membrane showed approximately 40% lower permeability than UP005, together with six times lower transmission of the test substance.
This demonstrates the importance of evaluating permeability and retention together: a membrane offering higher retention may involve a trade-off in permeability, depending on the application and operating conditions.
5. Membrane element design can improve operational efficiency
Membrane performance also depends on the spiral-wound element that houses the membrane.
The webinar introduced TurboClean elements, designed to address operational challenges such as bypass flow, recirculation, cleaning time, and handling.
The presentation reported the following potential operational benefits:
- Up to 35% water savings.
- 6% lower electrical current draw.
- 30% lower recirculation rate.
- Higher productivity through shorter cleaning times and higher crossflow velocities.
*These figures are the benefits reported in the presentation and should be assessed in the context of the relevant system design and operating conditions.
6. Match membrane properties to the application
Dairy protein ultrafiltration involves different priorities depending on the process. For milk and whey protein concentration, 10 kDa membranes are generally associated with capacity and throughput requirements, while 5 kDa membranes are commonly used when protein rejection is a priority.
More demanding separation requirements may call for higher-retention membrane options, such as the 3 kDa membrane presented in the webinar.
By evaluating membrane properties alongside product characteristics, element design, and operating conditions, processors can make more informed decisions about filtration performance and process objectives.
Meet our experts
To explore how ultrafiltration can support your dairy processes or to discuss specific application challenges, get in touch with our experts to identify the most suitable approach for your needs.