24 automotive design


Hose lines cut pollution to meet emissions standards


Engine manufacturers are relying on heatable hose line module for selective catalytic reduction technology. Georg Franz reports.


C


ompliance with increasingly strict exhaust emissions standards is one of the biggest challenges facing diesel engine manufacturers.


In 2011 the Tier 4i regulations will go into effect in the US, and in Europe the fourth level of emissions legislation will take hold in 2013 – and in the meantime, an increasing environmental and climate awareness is becoming obvious in various regulations in Asia.


The resulting requirements can be satisfied only with an effective gas after-treatment, because the necessary exhaust values can no longer be achieve by optimisations to the engine.


A very promising


alternative is the selective catalytic reduction technology, which transforms noxious nitrogen oxide (Nox) into steam and nitrogen with the help of a carbamide solution (AdBlue).


EPDM


With a heatable EPDM-based hose line, which was developed especially for the SCR process, ContiTech is a pioneer in the introduction of this future- orientated technology. Selective catalytic


reduction (SCR) technology long ago established itself in commercial road vehicles,


Soot particulate emissions can also be cut by as much


as 40 per cent, making it possible to cut nitrogen oxide emissions to less than 3.5 g/kWh.


In the meantime, engine manufacturers such as Deutz and MTU make use of the technology as well, and manufacturers of farm implements such as ACGO-Fendt also rely on the eco-friendly process as does the construction machinery manufacturer Liebherr.


Heating filaments


For instance, engine manufacturer Deutz is now offering a modular system for its compact engines that reduces noise and pollutant emissions – the DVERT, for example, Deutz Variable Emission Reduction Technology. The components ensure optimal performance and efficiency as well as compliance with specified emission thresholds.


In order to reduce nitrogen oxide emissions, it also utilises the SCR process and the lines developed especially for the technology by ContiTech Fluid Technology.


The hose line module transports the AdBlue carbamide solution needed to convert the pollutants into harmless nitrogen and water vapour and prevents it from freezing.


Fig. 1 The heatable EPDM-based SCR hose line module was developed specifically for the transport of carbamide (AdBlue). Photo: ContiTech


which must already comply with strict limit values in Europe and the US.


In the final analysis, the new technology makes it possible to reduce nitrogen oxide and hydrocarbon emissions by up to 80 per cent.


To convert nitrogen oxide, the AdBlue liquid carbamide solution carried in a separate tank is metered into the catalyst’s injection system via a media-resistant hose line. The problem here is that carbamide freezes at about -11°C, depending on the concentration.


The special feature of the


ContiTech solution is that the heatable hose, which runs between the carbamide tank and the pump module, is jacketed in a coat of EPDM into which heating wires capable of carrying electric voltage are integrated. In this way, both the hose and the medium


www.engineerlive.com


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36