Exhaust Catalyst Partition Drying via Inverted Ventilation

Solution Overview

Problem

The formation of a segregated catalyst layer inside the partition of exhaust gas purification catalysts tends to block or narrow the pores, leading to increased pressure drop, which is undesirable for efficient exhaust gas purification.

Innovation Solution

A method for producing an exhaust gas purification catalyst with a highly uniform catalyst layer in the thickness direction of the partition, involving the application of a catalyst layer forming material to one end of the partition and drying it from the opposite end, ensuring even drying and reducing segregation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If the catalyst layer is formed in a segregated manner inside the partition, then the catalyst layer can be positioned at a predetermined cell side, but the pores of the partition are blocked or narrowed, leading to increased pressure drop

Engineering Contradiction:

Improvecatalyst layer positioning precisionVSAvoidpressure drop increase

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

Instead of introducing drying air from the catalyst coating side (conventional method), the patent introduces drying air from the opposite side (uncoated portion side). This inverted approach allows the drying air to flow through the catalyst layer from the uncoated side, achieving uniform drying without blocking pores or increasing pressure drop.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent applies catalyst layer only to a predetermined length from one end of the partition, leaving the other end uncoated. This local quality approach creates an uncoated portion that serves as a drying air introduction path, enabling uniform drying while maintaining low pressure drop.

Inventive Principle:

Principle #3Local quality

2Object-affected harmful factors

If the catalyst layer is formed uniformly inside the partition, then the pressure drop increase is reduced, but the catalyst layer formation process becomes more difficult to control

Engineering Contradiction:

Improvepressure drop increaseVSAvoidcatalyst layer formation ease

Core Design Contradiction:

Object-affected harmful factorsVSEase of manufacture

Solution Approach 1:

The patent applies catalyst layer only to a predetermined length from one end of the partition, leaving the other end uncoated. This local quality approach creates an uncoated portion that serves as a drying air introduction path, enabling uniform drying while maintaining low pressure drop.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The uncoated portion acts as an intermediary region that facilitates uniform drying of the catalyst layer. By introducing drying air through this uncoated portion, the patent achieves uniform catalyst layer formation without direct contact between drying air and catalyst-coated surfaces.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Device complexity

If drying is performed from the same end where catalyst layer forming material is applied, then the drying process is simplified, but segregation of the catalyst layer occurs in the thickness direction

Engineering Contradiction:

Improvedrying process complexityVSAvoidcatalyst layer uniformity

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

Instead of introducing drying air from the catalyst coating side (conventional method), the patent introduces drying air from the opposite side (uncoated portion side). This inverted approach allows the drying air to flow through the catalyst layer from the uncoated side, achieving uniform drying without blocking pores or increasing pressure drop.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the drying air introduction direction from the conventional approach (same end as coating) to the opposite end. This dimensional change in the drying process enables uniform catalyst layer formation in the thickness direction by allowing air to penetrate through the uncoated portion and dry the catalyst layer evenly.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

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 method results in a catalyst layer that is more uniform and less likely to cause pressure drop increases, enhancing the efficiency of exhaust gas purification while maintaining low pressure drop.

Implementation Method 1

ventilating from the other end at which the second cell of the base material is open and drying the applied catalyst layer forming material

Methodology Applied

Scientific EffectEvaporation: Evaporation

Data Source

PatentUS20250177921A1Method for Producing Exhaust Gas Purification Catalyst

Publication Date: 2025.06.05 CATALER CORP

AI summary

The method includes: preparing a base material having a wall flow structure, including a first cell with an opening only at an first end, a second cell with an opening only at a second end, and a porous partition partitioning the first cell and the second cell; supplying a catalyst layer forming material to the first end and applying the catalyst layer forming material to an inside of the partition from the first end up to a predetermined length along the extension direction of the partition such that an uncoated portion where the second end is not coated with the catalyst layer forming material in a range facing the first cell of the partition in the extension direction of the partition is formed, and ventilating from the second end and drying the applied catalyst layer forming material.