Multizone Microporous Membrane for High-Throughput Filtration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing filtration technologies face challenges in achieving high throughput performance without increasing manufacturing costs or complexity, particularly in multilayer membranes, and existing asymmetric membranes are prone to non-uniformity and particle accumulation at interfaces.
Innovation Solution
A multizone, unsupported microporous filtration membrane with a specific three-zone structure, comprising a symmetric or asymmetric first and second zone, and an asymmetric third zone positioned between them, is fabricated through a triple slot casting process, ensuring integral zones without distinct interfaces, using polymers like PVDF and hydrophilic polymers, and optionally hydrophilic coatings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multiple layers of membranes are used to improve throughput, then fluid processing capacity is improved, but manufacturing cost increases
Solution Approach 1:
The single membrane is segmented into multiple functional zones (retentive zone with smaller pores and pre-filtration zones with larger pores) rather than using multiple separate membrane layers. This segmentation within a single layer reduces manufacturing complexity and cost while maintaining high throughput performance through optimized flow distribution across zones.
Solution Approach 2:
Different zones within the membrane have different pore sizes and structures optimized for specific functions: the retentive zone has smaller pores for fine filtration, while pre-filtration zones have larger pores for bulk flow and particle capture. This local quality variation allows each zone to perform its specific function efficiently, achieving high overall throughput without requiring multiple membrane layers.
2Productivity
If asymmetric membrane structure is used to improve throughput, then fluid processing capacity is improved, but membrane uniformity deteriorates
Solution Approach 1:
The asymmetric membrane is segmented into distinct functional zones with clearly defined boundaries. The retentive zone and pre-filtration zones are created as separate regions within the same membrane layer, each with uniform pore structures optimized for their specific functions. This segmentation maintains manufacturing precision within each zone while achieving overall asymmetric performance for high throughput.
3Manufacturing precision
If sequential casting process is used to create multizone membrane, then zone differentiation is achieved, but interface particle accumulation occurs
Solution Approach 1:
An intermediary transition zone is created between the retentive zone and pre-filtration zones. This transition zone has intermediate pore sizes that gradually bridge the gap between the two distinct zones, preventing sharp interfaces where particles would accumulate. The transition zone acts as a mediator that maintains smooth particle flow while preserving zone differentiation.
4Productivity
If tight surface modification is used to improve throughput, then fluid processing capacity is improved, but process complexity increases
Solution Approach 1:
The tight surface modification function is merged into the membrane formation process itself rather than being a separate post-processing step. The asymmetric structure with a dense retentive zone is created during the initial phase separation process, combining the benefits of tight surface filtration with high throughput in a single integrated manufacturing process, thereby reducing overall process complexity.
Data Source
AI summary
The present application relates to a multizone, unsupported, microporous, high throughput membrane. The membrane includes a first microporous zone, a second microporous zone, and a third microporous zone, where the third microporous zone is positioned between the first and second microporous zones, with the first, second, and third microporous zones being integral with one another. Further aspects of the present application include a process for making the membrane and a filtration cartridge with the membrane of the present application.