Wall Flow Particulate Filter Ash Removal via Solid Acid Catalyst
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Ash accumulation on particulate filters in internal combustion engines leads to increased pressure loss and reduced engine output, as existing technologies do not effectively address the removal of non-combustible ash during particulate matter removal processing.
Innovation Solution
A method involving a wall flow type particulate filter with a solid acid catalyst that lowers oxygen concentration and raises temperature to atomize ash, then releases it in an oxidizing atmosphere with SOx, using a solid acid with acid strength between sulfurous and sulfuric acid, to remove the ash from the filter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If PM removal processing is performed to remove particulate matter, then particulate matter is removed from the filter, but ash accumulates on the filter and pressure loss increases
Solution Approach 1:
The patent extracts and removes ash from the particulate filter by utilizing the difference in volatility between ash and particulate matter. Through controlled temperature rise and oxygen concentration adjustment, ash is volatilized and removed from the filter, while particulate matter is oxidized and removed separately. This extraction principle allows selective removal of ash without compromising the filter's particulate matter removal capability.
Solution Approach 2:
The patent changes physical and chemical parameters (temperature and oxygen concentration) to achieve ash removal. By controlling the temperature to a specific range and adjusting oxygen concentration, the patent creates conditions where ash becomes volatile and can be removed. This parameter change approach enables the filter to remove ash while maintaining its primary function of trapping particulate matter.
2Ease of manufacture
If the filter volume is reduced to lower manufacturing costs, then manufacturing costs decrease, but ash accumulation more rapidly increases pressure loss
Solution Approach 1:
The patent implements continuous ash removal through regular PM removal processing cycles. By continuously or periodically performing ash removal operations, the filter maintains its performance over time without requiring excessive volume. This continuous action allows smaller filters to maintain effectiveness, reducing manufacturing costs while preventing pressure loss.
Solution Approach 2:
The filter system performs self-maintenance by utilizing the PM removal processing to also remove ash. The same process that removes particulate matter also volatilizes and removes ash, eliminating the need for separate ash removal systems. This self-service capability allows cost-effective filter design without requiring additional components or excessive volume.
3Productivity
If PM removal processing is performed repeatedly, then particulate matter is continuously removed, but engine output gradually drops due to ash accumulation
Solution Approach 1:
The patent converts the harmful effect of ash accumulation into a beneficial process by utilizing ash volatilization during PM removal processing. The same high-temperature, high-oxygen conditions that oxidize particulate matter also volatilize ash, transforming ash from a harmful residue into a removable substance. This converts the harmful accumulation effect into a beneficial removal mechanism.
Solution Approach 2:
The patent uses oxygen as an intermediary substance to facilitate ash removal. By controlling oxygen concentration during PM removal processing, oxygen acts as a mediator that promotes ash volatilization. The oxygen enables the transformation of ash into volatile species without requiring direct contact or separate processing mechanisms, thus maintaining engine output while removing ash.
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
This method effectively reduces pressure loss and maintains engine output by efficiently removing ash from the particulate filter, allowing for smaller filter volumes and reduced manufacturing costs.
Implementation Method 1
the method renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter is lowered in concentration of oxygen and the particulate filter is raised in temperature to thereby atomize the ash
Implementation Method 2
hold the atomized ash in the solid acid in a dispersed state
Implementation Method 3
renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter in an oxidizing atmosphere contains SOx to thereby release the atomized ash which is held at the solid acid from the solid acid
Data Source
AI summary
A method of removing ash from a wall flow type particulate filter which is arranged in an exhaust passage of an internal combustion engine in which combustion is performed in an excess of oxygen for trapping particulate matter in exhaust gas, using a solid acid which is carried on the particulate filter, renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter is lowered in concentration of oxygen and the particulate filter is raised in temperature, and then renders the state of the particulate filter a state where the exhaust gas which flows into the particulate filter in an oxidizing atmosphere contains SOx.