A high-pressure SCR system with venting and pressure-stabilizing for marine diesel engine, comprising an SCR reactor (10), a gas intake pipeline (20), an exhaust pipeline (30), a bypass pipeline (40), a pneumatic pipeline (50), a first auxiliary pipeline (70), and a second auxiliary pipeline (80). When the exhaust gas of the diesel engine needs to undergo denitrification treatment, the exhaust gas of the diesel engine can enter from a flue gas inlet, sequentially pass through the gas intake pipeline (20), the SCR reactor (10), and the exhaust pipeline (30), and be discharged from a flue gas outlet, the exhaust gas undergoing denitrification treatment in the SCR reactor (10). When the exhaust gas of the diesel engine does not need to undergo denitrification treatment, the exhaust gas can enter the bypass pipeline (40) from the flue gas inlet and be discharged from the flue gas outlet, the exhaust gas in the SCR reactor (10) and exhaust pipeline being pushed by compressed air entering from the first auxiliary pipeline (70) and the second auxiliary pipeline (80) to be discharged from the flue gas outlet. The present system eliminates the original inlet air pipeline, simplifying the structure of the entire system so that the entire system is more compact, ensuring thorough ventilation and reducing the amount of air consumption. Also provided is a ship.

A system includes a controller configured to perform an enable operation responsive to receiving information indicative of an enable parameter, the enable operation includes: determining a predicted downstream NOx value of an exhaust gas stream exiting a NOx storage catalyst; determining a downstream NOx value of the exhaust gas stream exiting the NOx storage catalyst; determining an error between the predicted downstream NOx value and the determined downstream NOx value; comparing the error to an error threshold; and determining that the NOx storage catalyst is in good health responsive to determining that the error does not exceed the error threshold. The controller is further configured to perform a disable operation responsive to receiving information indicative of a disable parameter, the disable operation causing a deactivation of at least a portion of the controller.

Disclosed is a method for use in a process of selective catalytic reduction (SCR) after-treatment of an exhaust gas of an exhaust gas stream, where the process comprises the reduction of nitrogen oxides of the exhaust gas stream through the use of a reducing agent derived from an additive. The disclosed method comprises: defining an integrand to be the difference between the rate of injection of the additive and the rate of evaporation of the additive to the reducing agent multiplied by a coefficient (s), wherein the value of the coefficient (s) is between zero and one; producing an integral controller output proportional to the integral of the integrand with time; requesting a countermeasure based on the integral controller output to counteract solid deposits derived from the additive.

Method and system for the removal of nitrogen oxides, volatile organic compounds and particulate matter from engine exhaust gas at cold start conditions.

An exhaust treatment system includes an exhaust line, a series of emission treatment units, and an electronic control unit. The series of emission treatment units includes a catalytic unit, a particulate filter unit, an oxidation catalytic unit, a hydrogen injection unit, and a Lean NOx Trap (LNT) for trapping select emissions. A method of operating an exhaust treatment system includes introducing a fuel to a combustion engine of a motor vehicle, directing emissions from the combustion engine to an exhaust line, and passing the emissions in the exhaust line through a series of emission treatment units on the exhaust line. The method further includes injecting hydrogen into the exhaust line via a hydrogen injection unit, where an amount of hydrogen gas injected from a hydrogen inlet line reduces the trapped emissions in the LNT to an inert gas.

An aftertreatment system (100) includes a decomposition chamber (108), a reductant pump (120), a first dosing module (110), a second dosing module (112), and a controller (133). The first dosing module (110) is coupled to the decomposition chamber (108) and configured to receive reductant from the reductant pump (120). The second dosing module (112) is coupled to the decomposition chamber (108) and configured to receive reductant from the reductant pump (120) independent of the first dosing module (110). The controller (133) is communicatively coupled to the first dosing module (110) and the second dosing module (112). The controller (133) is configured to independently control a first volumetric flow rate of reductant provided from the first dosing module (110) into the decomposition chamber (108) and a second volumetric flow rate of reductant provided from the second dosing module (112) into the decomposition chamber (108).

The present disclosure describes methods for evaluating NOx conversion efficiency of a close coupled SCR unit of an EAS including the close coupled SCR unit and a downstream SCR unit. The determined NOx conversion efficiency of the close coupled SCR unit is used to diagnose the close coupled SCR unit and or EAS and to control operation parameters of the EAS and/or internal combustion engine operably connected to the EAS.

A heavy duty truck includes a diesel engine that generates an exhaust gas flow and an exhaust after-treatment system for treatment of the exhaust gas flow. The exhaust after-treatment system includes at least one temperature sensor at an underbody SCR system within the exhaust after-treatment system and a DEF injector upstream of a close-coupled SCR system within the exhaust after-treatment system. The DEF injector is operated to inject DEF into the exhaust gas flow at a rate that varies as a function of a temperature measured by the temperature sensor.

A heavy duty truck includes a diesel engine that generates an exhaust gas flow and an exhaust after-treatment system for treatment of the exhaust gas flow. The exhaust after-treatment system includes at least one heater and at least one selective catalytic reduction system downstream of the heater. The heater is operated to inject supplemental heat energy into the exhaust gas flow at a rate based on a difference between a target rate of heat energy in the exhaust gas flow at an inlet to the selective catalytic reduction system and a rate of heat energy supplied to the exhaust gas flow from the diesel engine.

A method for operating an internal combustion engine includes combusting a fuel and air mixture within a combustion chamber of an internal combustion engine, thereby forming an exhaust gas, passing the exhaust gas out of the combustion chamber, performing a startup procedure, the startup procedure including passing the exhaust gas from the combustion chamber to a storage unit, capturing criteria pollutants of the exhaust gas with the storage unit, passing the exhaust gas from the storage unit to an aftertreatment system, heating the aftertreatment system to an activation temperature with the exhaust gas from the storage unit, and subsequent to heating the aftertreatment system to the activation temperature, performing a secondary procedure, the secondary procedure including passing the exhaust gas from the combustion chamber to the aftertreatment system thereby forming a treated exhaust gas, and passing the treated exhaust gas to the storage unit.