Dual Density Nanofiber Media for Air Filtration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing nanofiber-based filtration media lack durability and efficiency due to their light basis weight and single-layer structure, which limits their ability to effectively filter a wide range of particulate sizes and prolong filter life.
Innovation Solution
A gradient filtration media is developed using multiple layers of nanofibers with varying diameters, formed through an electrospinning process, where the layers are strategically applied to a cellulose or synthetic substrate to enhance filtration efficiency and dust holding capacity, allowing for selective filtration and prolonged filter life.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If a single nanofiber layer is used to reduce basis weight and maintain lightness, then the filtration media becomes lighter and more breathable, but the durability and integral strength deteriorate due to the light basis weight preventing self-support
Solution Approach 1:
The patent applies composite materials by combining nanofibers with a base substrate to create a hybrid structure. The base substrate provides the necessary mechanical strength and self-support, while the nanofiber layer contributes filtration efficiency. This composite approach resolves the contradiction by allowing the nanofiber layer to be lightweight yet supported by the stronger base material, achieving both lightness and durability simultaneously.
Solution Approach 2:
The patent segments the filtration media into two functional layers: a base substrate layer providing structural support and a nanofiber layer providing filtration. This segmentation allows each layer to optimize its specific function without compromising the other, enabling the nanofiber layer to remain lightweight while the base substrate ensures overall structural integrity and self-support.
2Device complexity
If a single nanofiber layer is used to simplify structure, then the manufacturing process becomes simpler, but the filtration efficiency across wide particulate sizes deteriorates due to limited depth filtration capability
Solution Approach 1:
The patent segments the filtration function into two distinct layers with different pore structures. The base substrate layer handles larger particulates through its macro-porous structure, while the nanofiber layer captures finer particles through its micro-porous structure. This segmentation enables effective filtration across a wide range of particulate sizes without significantly increasing manufacturing complexity, as both layers can be integrated using established composite material techniques.
Solution Approach 2:
The patent applies local quality by giving each layer different structural characteristics optimized for specific filtration needs. The base substrate has a coarser structure suited for pre-filtration of larger particles, while the nanofiber layer has a finer structure for capturing smaller particles. This localized optimization of structure throughout the media enables comprehensive filtration efficiency across different particle sizes.
3Device complexity
If nanofibers are applied directly to corrugated support to reduce layers, then the structure becomes simpler, but the dust holding capacity deteriorates due to limited depth for particle accumulation
Solution Approach 1:
The patent segments the dust holding function between two layers: the base substrate layer provides initial particle capture and structural support, while the nanofiber layer provides additional depth and surface area for particle accumulation. This segmentation increases the total dust holding capacity compared to a single layer, while maintaining relatively simple structure through the integration of these two functional layers.
Solution Approach 2:
The patent adds another dimension to the filtration structure by incorporating a nanofiber layer that extends the filtration depth into the third dimension. This multi-layered approach creates additional volume for particle accumulation and dust holding, transforming the structure from a single-plane filtration to a multi-dimensional depth filtration system, thereby increasing dust holding capacity without excessive complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The gradient filtration media achieves superior air filtration performance, with increased dust holding capacity and extended filter life, outperforming conventional media in terms of MERV ratings and pressure drop resistance, making it suitable for industrial and HVAC applications.
Implementation Method 1
a first electrospun nanofiber layer comprising a first nanofiber, wherein the electrospun first nanofiber layer comprises a second influent surface and a second effluent surface and the first electrospun nanofiber layer at least partially coats the first influent surface of the filtration media substrate
Data Source
AI summary
The present invention generally relates to a dual density air filtration media that comprises a plurality of nanofibers layers formed from nanofibers having different fiber diameters. Due to the presence of these multiple nanofiber layers with different nanofiber diameters, the resulting filtration media of the present invention comprises a gradient density. In particular, the present invention uses a novel combination of two or more layers of nanofibers made via an electrospinning process, wherein the nanofiber layers made up from different fiber sizes are strategically applied to a cellulose or synthetic base material or substrate, to thereby maximize the filtration efficiency and dust holding capacity of the resulting filtration media.