Abstract: A method for testing a condition of a catalyst is provided. The method includes providing a gas source in communication with the catalyst. The method also includes passing compressed gas from the gas source over the catalyst at normal operating temperature. The method further includes invoking a reaction with the catalyst based on the passage of the compressed gas. The method includes measuring a performance of the catalyst based on the reaction.

Abstract: A system to protect an after treatment system from the effects of hydrocarbon accumulation on a catalyst. An engine system microprocessor using software estimates the amount of hydrocarbon accumulation on the after treatment system based on engine system parameters and other parameters. The accumulated hydrocarbons can cause an exothermic event if the catalyst temperature is allowed to ramp up too quickly. Similarly, accumulated hydrocarbon can temporarily reduce after treatment system performance. In the case of SCR, the microprocessor can control a reductant injector to modulate the amount of reductant being injected into the after treatment system to control the amount of ammonia slip. Alternatively or in addition to, the microprocessor can communicate with proper electronic control modules to modulate the engine system parameters such as engine speed, fuel, and back pressure to control engine exhaust flow temperature during operation of the engine system.

Abstract: An emissions control system includes a Selective Catalytic Reduction (SCR) device, one or more monitoring devices and one or more sensors. The system further includes a controller configured to determine an operating emissions gas conversion ratio of the SCR device. The controller is further configured to determine an injection amount of a reduction agent to maintain an operating emissions gas conversion ratio of the SCR device and to adjust the operating emissions gas conversion ratio to a target emissions gas conversion ratio by adjusting the injection amount of the reduction agent to the SCR device. The system utilizes a Time-Temperature model to determine the target emissions gas conversion ratio and/or reduction agent injection ratio. The system further includes a reduction agent injector configured to supply the adjusted injection amount of the reduction agent to the SCR device.