Solid ammonia SCR – a tool for meeting future Ultra-low NOx standards

13-12-2018

In presentations made at the 4th Automotive Exhaust Systems Summit in Düsseldorf as well as at the Integer Emissions Summit in Indianapolis, Amminex has demonstrated how current retrofit applications confirm the potential for using ASDS™ in future Ultra-low NOx exhaust system configurations.

In the presentations CTO and co-founder of Amminex Tue Johannessen presented the latest ASDS™ progress while linking it to current and future applications.

“Direct ammonia gas dosing from ASDS™ is an important tool for OEMs to reach future ultra-low NOx emission targets while maintaining the fuel economy advantage of diesels,” Tue Johannesen stated as the key message of the presentation.

The ability to reach the targeted ultra-low NOx level will require engine and combustion development as well as more sophisticated exhaust system configurations. If the thermal boundaries for dosing reductant to the catalyst are expanded, i.e. enabled well below 200°C, the required extra work of the engine for thermal management is reduced which again leads to reduced fuel economy impact. 

Tackling NOx emissions at low engine load
Referring to data from the world’s first RCV fleet retrofit project, Dr. Johannessen demonstrated how the ASDS technology can solve the critical issue of NOx emissions at low engine load without thermal management.

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“With average speed well below 5 km/h, the Refuse Collection Vehicles in London can operate month after month in a fully passive DPF mode because the engine does not require EGR to support low tailpipe level at low engine load. As a nice domino effect of the ammonia dosing system, the good SCR function triggers reliable filter operation. Avoiding EGR at low load reduces engine-out PM and eliminated field issues with incomplete active DPF regeneration,” Tue Johannessen said.

Another key point in the presentation was how Tue Johannessen envisions ASDS as a key component in future exhaust aftertreatment system configurations, enabling the expected NOx reduction targets in Euro VII/Ultra-low NOx standards. Benefits and drawbacks of various exhaust configurations were discussed, including how using ASDS can provide a 30-40% lower backpressure of compact mixer zones due to the higher degree of freedom provided by gaseous dosing.

“To sum it all up: No deposit risk and more flexibility. For future dual-dosing configurations, this impact on back-pressure reduction is even more important and one of the activities ongoing at Faurecia,” Dr. Johannessen concluded.

If you you would like a copy of the presentation(s), please send an e-mail to Communications Manager Morten K. Thomsen where you explain why you are interested.