TY - JOUR
T1 - Analysis of lacquer deposits and plugging found in field-tested EGR coolers
AU - Lance, Michael J.
AU - Storey, John
AU - Lewis, Sam
AU - Sluder, C. Scott
PY - 2014
Y1 - 2014
N2 - All high-pressure exhaust gas recirculation (EGR) coolers become fouled during operation due to thermophoresis of particulate matter and condensation of hydrocarbons present in diesel exhaust. In some EGR coolers, fouling is so severe that deposits form plugs strong enough to occlude the gas passages thereby causing a complete failure of the EGR system. In order to better understand plugging and means of reducing its undesirable performance degradation, EGR coolers exhibiting plugging were requested from and provided by industry EGR engineers. Two of these coolers contained glassy, brittle, lacquer-like deposits which were analyzed using gas chromatography-mass spectrometry (GC-MS) which identified large amounts of oxygenated polycyclic aromatic hydrocarbons (PAHs). Another cooler exhibited similar species to the lacquer but at a lower concentration with more soot. The authors propose that lacquer deposits form when oxygenated PAHs present in the exhaust condense on the cooler walls subsequently experience nitric acid catalyzed polymerization in the presence of aldehydes. A fourth cooler contained large amounts of oil which likely originated from a failed lubricant seal. In light of these results, recommendations for preventing plugging of EGR coolers are suggested.
AB - All high-pressure exhaust gas recirculation (EGR) coolers become fouled during operation due to thermophoresis of particulate matter and condensation of hydrocarbons present in diesel exhaust. In some EGR coolers, fouling is so severe that deposits form plugs strong enough to occlude the gas passages thereby causing a complete failure of the EGR system. In order to better understand plugging and means of reducing its undesirable performance degradation, EGR coolers exhibiting plugging were requested from and provided by industry EGR engineers. Two of these coolers contained glassy, brittle, lacquer-like deposits which were analyzed using gas chromatography-mass spectrometry (GC-MS) which identified large amounts of oxygenated polycyclic aromatic hydrocarbons (PAHs). Another cooler exhibited similar species to the lacquer but at a lower concentration with more soot. The authors propose that lacquer deposits form when oxygenated PAHs present in the exhaust condense on the cooler walls subsequently experience nitric acid catalyzed polymerization in the presence of aldehydes. A fourth cooler contained large amounts of oil which likely originated from a failed lubricant seal. In light of these results, recommendations for preventing plugging of EGR coolers are suggested.
UR - http://www.scopus.com/inward/record.url?scp=84899511992&partnerID=8YFLogxK
U2 - 10.4271/2014-01-0629
DO - 10.4271/2014-01-0629
M3 - Conference article
AN - SCOPUS:84899511992
SN - 0148-7191
VL - 1
JO - SAE Technical Papers
JF - SAE Technical Papers
T2 - SAE 2014 World Congress and Exhibition
Y2 - 8 April 2014 through 10 April 2014
ER -