Honeycomb Filter Catalyst Loading Pattern
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional honeycomb filters used in diesel particulate filters face issues with soot clogging due to peeling off from the partition wall, leading to decreased purifying efficiency and increased pressure loss, especially when loaded with catalysts for continuous regeneration.
Innovation Solution
A honeycomb filter design with a polygonal sectional shape and specific catalyst loading patterns on the partition walls, where the first partition wall parts have a catalyst loading area ratio exceeding 10% and the second partition wall parts have a ratio of 10% or less, effectively reducing soot peeling off and maintaining regeneration efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the partition wall is loaded with exhaust-gas purifying catalyst for continuous regeneration, then the regeneration efficiency is improved, but soot peeling off from the partition wall increases causing cell clogging
Solution Approach 1:
The partition wall is divided into different regions with different catalyst loading characteristics. Specifically, the partition wall has a first region with a catalyst loading area ratio of 10% or less and a second region with a catalyst loading area ratio of more than 10%. This local differentiation allows the filter to maintain regeneration efficiency while reducing soot peeling by having areas with lower catalyst coverage where soot is less likely to peel off.
2Productivity
If soot accumulates on the partition wall surface, then the purifying efficiency is improved by trapping PM, but the pressure loss increases due to cell clogging from peeled soot
Solution Approach 1:
By creating regions with different catalyst loading ratios on the partition wall, the invention allows soot to accumulate in controlled patterns. The regions with lower catalyst loading (10% or less) reduce soot peeling and prevent cell clogging, thereby maintaining low pressure loss, while still allowing sufficient soot accumulation to maintain purifying efficiency.
3Productivity
If the catalyst loading area ratio is increased to improve continuous regeneration, then the regeneration capability is enhanced, but the soot peeling off and cell clogging worsen
Solution Approach 1:
The partition wall is designed with spatially varying catalyst loading ratios, creating a heterogeneous structure where different regions serve different functions. This avoids the need for uniform high catalyst loading that would cause excessive soot peeling, while still providing sufficient catalyst coverage in certain regions to maintain continuous regeneration capability.
Solution Approach 2:
The partition wall surface is segmented into multiple regions with different catalyst loading characteristics. This segmentation allows the system to balance regeneration needs with soot adhesion requirements, preventing cell clogging while maintaining regeneration functionality through the distributed catalyst regions.
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 design effectively suppresses soot peeling off from the partition wall, preventing clogging and maintaining the purifying efficiency and reducing pressure loss during continuous regeneration.
Implementation Method 1
continuous regeneration with the catalyst loaded at the partition wall burns the soot accumulated on the surface of the partition wall
Data Source
AI summary
A honeycomb filter includes a pillar-shaped honeycomb structure body having a porous partition wall disposed to surround a plurality of cells and a plugging portion, wherein the partition wall defining inflow cells includes partition wall parts making up sides of polygon that is sectional shape of each cell, the partition wall parts each having a surface that is a face defining the inflow cell, the partition wall part is either a first partition wall part loaded with the exhaust-gas purifying catalyst on the surface so that a percentage of the area loaded therewith exceeds 10%, or a second partition wall part loaded with the exhaust-gas purifying catalyst so that a percentage of the area loaded therewith is 10% or less, and the partition wall is configured to include one or more the first partition wall parts and one or more the second partition wall parts as the partition wall parts.