The quest to reduce diesel engine emissions has resulted in a progressive trend of emissions technology advancements. This technology not only has created more effective SCR NOX emission controls, it has done so with relatively little trade-offs in performance. Today, diesel engine emissions are similar to their non-diesel engine counterparts. Here are some new technologies that are changing the face of diesel emissions treatments and helping safeguard our environment.
Ammonia Creation and Conversion Technology (ACCT)
ACCT uses SCR engine control processes and technology to lower the temperatures of existing engine treatments. This, in turn, helps the treatments achieve greater SCR NOX reduction efficiency and avoiding degradation of the treatments due to exposure to extremely high temperatures.
Advancements in SCR systems have long helped in the fight against NOX via AdBlue fluid. AdBlue turns NOX exhaust gases into harmless nitrogen and water. Without ACCT, it works best when engines are running hot and much less effectively or not at all with colder or cold engines. With ACCT, treatments such as AdBlue are enabled to work at much cooler temperatures, which has produced significant gains in reductions in tailpipe emissions.
The cold start is something almost everyone who has ever been around a diesel engine is familiar with. That great plume of bluish-gray exhaust is a cold start signature and those plumes are filled with toxic emissions. That continues until the vehicle’s catalytic converter warms up and is able to work effectively.
The ACCT system helps the SCR system work at temperatures as low as 140 degrees Fahrenheit (60 degrees Celsius.) What that means practically is that the SCR system is able to start working earlier at cooler temperatures, which gives greater coverage for NOX emissions throughout the driving cycle. The ACCT system is being actively improved and is available for all diesel engine systems.
Other Technology Improvements and Breakthroughs
The SpeedStart 48-volt switched reluctance starter generator is reported to reduce NOX with little or no effect on fuel economy or CO2 emissions. This belt enabled generator provides braking and torque assistance, which helps reduce exhaust emissions by nine percent. This new type of starter is being fitted for everyday vehicles currently.
Technology is changing the effectiveness of SCR NOX emissions controls and as the quest to control NOX becomes more widespread, that trend is likely to continue. These two advancements are great steps, but they are also par for the course for an industry that is quickly adapting to emissions controls and awareness.