Tighter emission levels challenge construction machinery industry

02/18/2014 16:32

 A major theme on the list of innovations expected at bauma 2010 on April 19-25 in Munich, Germany, are going to be cross-sector approaches to reducing emissions.

The international trade fair for construction machinery, building material machines, mining machines, construction vehicles and construction tools are happening only a few months before new emissions directives be given force: from 2011, while using the Stage III B Directive 97/68/EC and Tier 4 U.S. emissions legislation, new interim limits will sign up for emissions from non-road vehicles, such as diggers, road rollers and cutters. E.g., particulate levels are to be reduced by as much as 94 percent in comparison to the actual Stage III A.

The new directives is likely to make exhaust after-treatment systems for equipment over 50 hp absolutely imperative,a�? said Gunnar Stein, off-road line manager for AVL GmbH in Graz. AVL is regarded as among the worlda�?s leading companies inside growth of drive systems. It advises and supports many famous engine and construction machinery manufacturers, which will convene at bauma.

Exhaust after-treatment imperative
To have this ambitious target, the measures that were worn-out up to now for internal engines, like mechanical and electronic control units, common rail systems, electric charging and exhaust gas recirculation, won’t be adequate.

Variant 1: Exhaust gas recirculation and particulate filters
Based on the experts, there’s 2 main technological routes to having this necessary reduction in emissions. A proven way is always to lessen the a higher level nitrogen oxide by recirculating the exhaust gas in the engine. The resultant increased particulate emissions must then be collected in a very particulate filter. One problem with it is that the exhaust gas has to be cooled before recirculation.

a�?Expect as much as 25 % greater heat input in to the engine cooling system when compared with Stage III A engines,a�? Stein said. a�?This will likely require larger cooling surfaces and maybe higher fan performance. The former means the engine and vehicle manufacturers will face a problem with space from the engine compartment, plus the latter means an extra energy user will be required.a�?

Variant 2: Combating nitrogen oxides with SCR systems
Within the second technological route, the engine is adjusted to low particulate levels. However, therefore accepting increased levels of nitrogen oxide from the exhaust gas flow. These can then be dealt with using systems involving urea injection (SCR).

Unwanted side effects allow it to be complicated
a�?Happens III B and IV exhaust gas regulations are a challenge for both engine manufacturers and machine manufacturers, because of these exhaust gas stages not just the engine, but also different components inside exhaust after-treatment and installation conditions play a major part in complying while using the levels,a�? said Frank Diedrich, exhaust gas expert for VDMA, Germanya�?s engineering federation, as well as the Committee for European Construction Equipment. a�?The excess exhaust gas after-treatment features a�?side effects,a�? which will strongly influence the creation of mobile machines in the future a��� one example is, increased noise emission, rising temperatures as well as the desire for extra installation space. In addition, it will have increased technological complexity keep fuel consumption low and adapting the exhaust gas systems in sometimes less-than-ideal deployment conditions in the construction industry.

Low fuel consumption certainly makes it attractive, but a different operating material really needs to be combined with the urea, which further cuts down on the cost benefits,a�? Stein said. From todaya�?s perspective, both systems has to be combined so as to conform to the demands of Stage IV, which has a further lowering of nitrogen oxide levels by nearly 88 percent from 2014.

Bauma fuses industry expertise
The revolutionary emission directives might be a central theme for both the international exhibitors plus the trade public at bauma. In accordance with show organizers, there will be the ability to have an overview of the innovations and solutions state within this topic by engine developers, component manufacturers and construction machinery producers.

Price increases seem inevitable
Whichever route the makers choose to take, one thing seems certain: prices will rise. Based on Stein, doing the measures known will spot costs for Stage IV engine and exhaust gas treatment almost doubling.

a�?All sorts of things that manufacturers must consider the pros and cons of the numerous technical solutions, in order that they develop certainly not the lowest priced solution, but instead the concept that are going to be most cost-effective on the whole lifecycle,a�? he was quoted saying.