Efficient exhaust gas aftertreatment
Liebherr meets the increasingly stricter emissions standards with systems expertise. We developed our own exhaust gas aftertreatment systems, which are optimally combined with our diesel engines. These systems reliably reduce exhaust gas emissions and harmful particles.
D9508 diesel engine: Nitrogen oxide and particle emissions are measured at the test bench.
Vertical integration has a long tradition at Liebherr. We manufacture key components and systems ourselves. In view of the stricter emissions standards, we decided on our own injection system including engine control. Liebherr offers a standard basic engine. This engine can be flexibly adapted in accordance with the modular principle with small modifications or by exhaust gas aftertreatment systems. In this way we are able to meet the different emission regulations of different countries and regions with one engine architecture.
Modular system for every emission standard
D946 A7 diesel engine from Liebherr for emissions stage IV
SCRonly technology for stage IV/tier 4 final
For exhaust gas aftertreatment, Liebherr uses SCRonly technology for both stage IV and tier 4 final. The optimised system allows us to observe limit values without the need for a diesel oxidation catalyst (DOC), particulate filter (DPF) and exhaust gas recycling (EGR). The continuous and precise control of emissions by means of on-board diagnostics contributes to the high level of efficiency. At the same time, the efficiency of the SCR catalytic converter was improved. For improved and more accurate metering, Liebherr now injects the AdBlue urea solution with injectors, which permit better atomisation and thus an even more efficient reduction of the nitrogen oxide.
Overview of advantages
The SCRonly-technology from Liebherr without an oxidation catalyst and particulate filter stands out in the industry. The innovative system offers numerous advantages:
- Saves space during installation
- Less weight
- No need to regularly clean a particulate filter
- Longer oil change intervals
- Lower procurement and maintenance costs
- Lower cooling requirement thanks to omission of exhaust gas recycling
Flow analysis of SCR system
Strategy for emissions stage V
Liebherr is already preparing for stage V of the European emissions limit values from 2019 and has developed the innovative SCRFilter system. This system is already used in machines for tunnelling and is certified for stage IV, as well as the Swiss market. The Liebherr solution comprises a DOC catalytic converter, a SCR catalytic converter and a SCR-coated particulate filter. The maintenance-friendly technology permits easy access to the new SCRFilter. The filter needs to be cleaned after 4,500 working hours at the earliest and this can be done in Liebherr's own Reman centres.
