1990-02-01

Trapping Performance of Diesel Particulate Filters 900107

Exhaust particulates from diesel engines have become one of the most severe air pollution problems. The filter trap method is used to control diesel exhaust particulates. Hence, we have conducted an evaluation study of filter traps. In order to clarify the trapping performance such as filtration efficiency and pressure drops of the filter, four kinds of cordierite honeycomb type, two kinds of cordierite foam type and a mullite corrugation type filter were tested.
For the honeycomb type filters, it is clear that the micro-pore size mainly affects the filtration efficiency and both the micro-pore size and the cell wall thickness mutually affect pressure drop. Furthermore, it was revealed that the pore size affects the filtration efficiency and pressure drop for the foam type filters. The Mullite corrugation type filter showed the highest filtration efficiency.
From the experimental results, it was concluded that the mullite corrugation type and the honeycomb type filter of small micro-pore size and thin cell wall thickness are desirable as diesel particulate filters.
AS A MEANS FOR the reduction of diesel exhaust particulates, improvement in combustion through engine modification has been studied mainly so far. In the case of more strict requirements such as the 1987 regulation in the United States, it was considered difficult to satisfy the requirements by engine modifications only. At that time studies of reduction processes by the after treatment system began.
* Numbers in Parentheses designate References at end of paper.
The filter trap method is considered the most promising method for the reduction of exhaust particulates in the exhaust system. This method entails a ceramic filter being set into the exhaust system to temporarily trap exhaust particulates. The trapped particulates are then burnt again when the temperature of the exhaust and the oxygen level reach the point where combustion is possible, after which the particulates are exhausted as gas. The filter remains attached to the engine and is used continuously, repeating the sequence of collection and recombustion of exhaust particulates.
The authors are presently carrying out research with the aim of developing a practical filter trap system and method of usage. This report covers the results of examining the collecting ability of three types and seven kinds of filters, as well as a proposal regarding the more efficient filters.
No Caption Available
No Caption Available

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Nano Particulate Matter Evolution in a CFR1065 Dilution Tunnel

2009-01-2672

View Details

TECHNICAL PAPER

Fresh and Aged SCRT Systems Retrofitted on a MY 1998 Class-8 Tractor: Investigation on In-use Emissions

2011-24-0175

View Details

JOURNAL ARTICLE

Diesel Exhaust Aerosol Measurements Using Air-Ejector and Porous Wall Dilution Techniques

2011-01-0637

View Details

X