Exhaust Treatment System for an Internal Combustion Engine to Display the Quality of a Diesel Exhaust Fluid ('DEF')

摘要

An exhaust treatment system (10) for an internal combustion engine (12), comprising: an exhaust conduit (14) in fluid communication with and adapted to receive an exhaust gas (15) from the internal combustion engine (12); a diesel exhaust fluid ("DEF"); Source in fluid communication with the exhaust conduit (14), the DEF source supplying a quality factor DEF (30); a selective catalytic reduction ("SCR") apparatus (20) communicating with the exhaust conduit (14 ) is in fluid communication and configured to receive the exhaust gas (15); an NO sensor (62) in fluid communication with the exhaust conduit (14), the NO sensor (62) downstream of the SCR device (20 ) and configured to detect an NO concentration value; anda control module (50) in communication with the DEF source and the NO sensor (62), the control module (50) storing a diagnostic adaptation factor (82) and an expected NOx value (84), wherein the diagnostic adaptation factor ( 82) is an indication of the quality factor for the DEF, the control module (50) comprising: a dosing adaptation module (72) for determining a control adaptation factor (94) that directly affects the amount of DEF (30) supplied based on a deviation between the NO concentration value and the expected NO value (84); and a reductant fluid quality test module (88) that initiates a reductant fluid quality test, wherein the reductant fluid quality test module (88) suspends the supply of the DEF (30) until the DEF (30) charged to the SCR device (20) is degraded and then the DEF supply and wherein the reductant fluid quality test module (88) further monitors the DEF source and determines the amount of DEF delivered from the DEF source during the reductant fluid quality test, the reductant fluid quality test module (88) communicating with an efficiency diagnostic module (76), determining an SCR efficiency value (104) when the amount of DEF delivered from the DEF source is within a specified range; characterized in thatthe diagnostic adaptation factor (82) is selectively updated with the control adaptation factor (94); the efficiency diagnostic module (76) determines the SCR efficiency value (104) based on an upstream NO value and the NO concentration value; andthe control module (50) comprises a judging module (78) for determining whether the SCR efficiency value (104) is greater than an SCR efficiency threshold and wherein the diagnostic adaptation factor (82) is set to the control adaptation factor (94) when the SCR Efficiency value (104) is greater than the SCR efficiency threshold (104).