Particulate Filter With Surface Catalytic Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated DeNOx catalysts within diesel particulate filters (DPFs) increase soot-loaded backpressure, leading to fuel consumption penalties and regeneration challenges, due to the complexity and space requirements of multiple components in exhaust systems.
Innovation Solution
A ceramic particulate filter with a porous catalytic coating deposited on its outer surface, allowing gases to pass through while trapping particulate matter, reducing backpressure by preventing catalytic material interaction with soot and ash, and maintaining permeability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If DeNOx catalyst is integrated within the DPF wall porosity, then NOx conversion is achieved, but soot-loaded backpressure increases
Solution Approach 1:
The catalyst is segmented from the filter wall structure by placing it in a separate channel rather than embedding it within the wall porosity. This segmentation prevents the catalyst from directly interacting with and blocking the filter walls, thereby maintaining lower backpressure while still achieving NOx conversion in the dedicated catalyst channel.
Solution Approach 2:
The catalyst is moved from a two-dimensional wall surface to a one-dimensional channel space. By placing the catalyst in a separate channel rather than on the wall surface, the invention creates a dedicated pathway for catalytic reactions that does not interfere with the filtration function, thus reducing backpressure penalties.
2Reliability
If multiple components (DPF and DeNOx catalyst) are used, then PM and NOx emissions are controlled, but exhaust system complexity and space increase
Solution Approach 1:
The DPF and DeNOx catalyst functions are merged into a single integrated filter unit. The filter walls perform particulate matter filtration while a dedicated channel within the same structure houses the DeNOx catalyst, eliminating the need for separate components and reducing exhaust system complexity.
Solution Approach 2:
The integrated filter structure performs multiple functions simultaneously: the porous walls trap particulate matter while the dedicated catalyst channel converts NOx. This multi-functionality allows a single component to replace what would traditionally require separate DPF and DeNOx catalyst systems.
3Stress or pressure
If high porosity filter walls are used, then backpressure is reduced, but manufacturing difficulty increases
Solution Approach 1:
The invention changes the porosity parameter of the filter walls to optimize the balance between backpressure and manufacturability. By selecting a moderate porosity range (30-65%) rather than extremely high porosity, the walls maintain sufficient permeability to reduce backpressure while remaining easier to manufacture with consistent structural integrity.
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 solution decreases backpressure penalties, improves fuel efficiency, and simplifies regeneration by depositing catalytic material on the surface rather than within the filter's porosity, enhancing NOx conversion efficiency and reducing the risk of catalytic deactivation during regeneration.
Implementation Method 1
a porous catalytic coating deposited on an outer surface of the porous walls, wherein each of the inlet channels is in fluid communication with at least one of the outlet channels through the catalytic coating and the porous wall
Implementation Method 2
the catalytic material removes gases, such as nitrogen oxides (NOx), from gases passing through the filter
Implementation Method 3
each of the porous walls has a continuous porous structure capable of trapping particulate matter
Data Source
Figure 1(a)~1(b)
Figure 2(a)~2(b)
Figure 3(a)~3(c)
AI summary
A ceramic particulate filter having a porous catalytic material deposited on walls within the filter. Particulate matter is trapped in the walls of the filter and the catalytic material removes gases, such as nitrogen oxides (NOx), from gases passing through the filter. The filter, in one embodiment, is adaptable for use with internal combustion (gas and diesel) engines. A method of making the filter is also described.