A controller for controlling operation of an aftertreatment system that is configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to: generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter; generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter; generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate of the SCR catalyst.

A controller for controlling operation of an aftertreatment system that is configured to treat constituents of an exhaust gas produced by an engine, the aftertreatment system including a selective catalytic reduction (SCR) catalyst, the controller configured to: generate a short-term cumulative degradation estimate of the SCR catalyst corresponding to reversible degradation of the SCR catalyst due to sulfur and/or hydrocarbons based on a SCR catalyst temperature parameter; generate a long-term cumulative degradation estimate of the SCR catalyst corresponding to thermal aging of the SCR catalyst based on the SCR catalyst temperature parameter; generate a combined degradation estimate of the SCR catalyst based on the short-term cumulative degradation estimate and the long-term cumulative degradation estimate; and adjust an amount of reductant and/or an amount of hydrocarbons inserted into the aftertreatment system based on the combined degradation estimate of the SCR catalyst.

A method of calculating a nitrogen oxide (NOx) mass reduced from a lean NOx trap (LNT) during regeneration includes calculating a C3H6 mass flow used to reduce the NOx among a C3H6 mass flow flowing into the LNT of an exhaust purification device, calculating a NH3 mass flow used to reduce the NOx among a NH3 mass flow generated in the LNT, calculating a reduced NOx mass flow based on the C3H6 mass flow used to reduce the NOx and the NH3 mass flow used to reduce the NOx, and calculating the reduced NOx mass by integrating the reduced NOx mass flow over a regeneration period.

During execution of a first purification process of fluctuating a hydrocarbon concentration in exhaust gas flowing into a first catalyst with an amplitude within a prescribed range at a time interval within a prescribed range, when a switch request to a second purification process of purifying NOx in a second catalyst by adding urea water into the exhaust gas is generated, the switch to the second purification process is prohibited on the condition that a current NOx purification rate (a first purification rate R1) is higher than a purification rate (a second purification rate R2) on the assumption that the second purification process is executed, and an HC poisoning recovery stand-by process of reducing an additive amount of hydrocarbon per once in the first purification process is executed so as to reduce a slip amount of hydrocarbon into the downstream of the first catalyst.

The present invention provides a fuel supply system, for an eco-friendly ship, which selectively uses an existing fuel and an ammonia fuel or uses a mixture thereof as a fuel for a propulsion engine and a power generation engine of a ship so as to follow ship greenhouse gas regulations to be reinforced in phases at major points until 2050.

The present invention provides a fuel supply system, for an eco-friendly ship, which selectively uses an existing fuel and an ammonia fuel or uses a mixture thereof as a fuel for a propulsion engine and a power generation engine of a ship so as to follow ship greenhouse gas regulations to be reinforced in phases at major points until 2050.

A work vehicle may include an internal combustion engine, aftertreatment system, and at least one controller. The controller is configured to use a temperature of the aftertreatment system to determine a hydrocarbon level of the aftertreatment system, and set an idle speed of the engine to high idle if the hydrocarbon level is above a hydrocarbon ceiling, to ultra-low idle if the hydrocarbon level is below a hydrocarbon floor, and to low idle if the hydrocarbon level is between the hydrocarbon floor and the hydrocarbon ceiling.

A work vehicle may include an internal combustion engine, aftertreatment system, and at least one controller. The controller is configured to use a temperature of the aftertreatment system to determine a hydrocarbon level of the aftertreatment system, and set an idle speed of the engine to high idle if the hydrocarbon level is above a hydrocarbon ceiling, to ultra-low idle if the hydrocarbon level is below a hydrocarbon floor, and to low idle if the hydrocarbon level is between the hydrocarbon floor and the hydrocarbon ceiling.

A method for determining the hydrocarbon (HC) oxidation performance of an oxidation catalyst device (OC) includes communicating gas to the OC inlet over a time frame, measuring the NOx content of the OC outlet gas using a NOx sensor over the time frame, wherein the temperature of the OC increases over the time frame, and correlating an increased NOx measurement over the time frame to an increased OC HC oxidation performance. The NOx sensor can be operated in a low temperature mode during the time frame. The method can further include determining the temperature of the OC over the time frame and correlating the HC oxidation performance to the OC temperature, and/or correlating a maximum NOx concentration measured during the time frame to the OC temperature measured at the same time. HC slip through the OC can be identified when the measured NOx content of the OC outlet gas decreases.

A method for determining the hydrocarbon (HC) oxidation performance of an oxidation catalyst device (OC) includes communicating gas to the OC inlet over a time frame, measuring the NOx content of the OC outlet gas using a NOx sensor over the time frame, wherein the temperature of the OC increases over the time frame, and correlating an increased NOx measurement over the time frame to an increased OC HC oxidation performance. The NOx sensor can be operated in a low temperature mode during the time frame. The method can further comprise determining the temperature of the OC over the time frame and correlating the HC oxidation performance to the OC temperature, and/or correlating a maximum NOx concentration measured during the time frame to the OC temperature measured at the same time. HC slip through the OC can be identified when the measured NOx content of the OC outlet gas decreases.