Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Catalytic converter gets the pollution out of diesel engines

08.09.2004


In the near future the usual summer ozone peaks exceeding the allowed threshold may be a thing of the past: the Paul Scherrer Institute (PSI) in Switzerland has developed a new type of catalytic conversion system, which filters nearly all nitrogen oxides out of diesel exhaust gases using a refined control technology. This eliminates the main cause of summer ozone build-up. The process requires a non-toxic urea solution, which future diesel engine commercial vehicles can take with them in a separate refillable tank.



Diesel engines are looked upon as relatively economic and environment-friendly, because they have a better fuel efficiency than gasoline engines. But burning diesel also has a grave disadvantage: it produces nitrogen oxides, which enhance the build-up of hazardous ozone during periods of high solar radiation. “In the end, diesel engines today are the main cause for high ozone values during summer”, says Oliver Kroecher, Exhaust Gas Aftertreatment Group Manager at PSI. Already by 2005, exhaust gas standards for diesel engines are to be tightened massively throughout Europe. And further steps reducing the threshold are planned.

To comply with the new threshold values engine manufacturers are now focussing on the so-called SCR (Selective Catalytic Reduction) technology. Here nitrogen oxides are transformed into nitrogen and water vapour using a catalytic converter and by adding a harmless urea solution. This compelling principle could establish itself in the foreseeable future in all commercial diesel-powered commercial vehicles. In future drivers should get used to refilling an additional urea tank.


Zero emission for combustion engines is long term objective PSI scientists have now developed a practicable SCR catalytic converter that disposes over 90% of the nitrogen oxides in exhaust gases. Kroecher describes the PSI advantages over other SCR prototypes: “Our converter has minimal dimensions and can prevent the escape of ammonia generated during the reaction, thanks to an ingenious regulating system.” To optimise the nitrogen oxide dismantling, the amount of urea added adapts continuously to different drive phases. “Our regulator system all but anticipates the engine activity and can therefore react fast enough to changes”, says Kroecher.

With the nitrogen oxide output going down the problem with harmful soot particles from diesel engines will also be defused. While diesel engines could be tuned to a low soot production, this will however increase the nitrogen oxides. The new SCR catalytic converter strongly reduces this drawback. PSI researchers want to achieve even more. Kroecher: “In the long run, we’re working on zero-emission concepts, in order to develop combustion types creating no other pollutants than carbon dioxide.”

The work on the SCR catalytic converter was carried out together with industry partners and with the support of the Swiss Federal Office of Energy. The Measurement and Control Laboratory at the Swiss Federal Institute of Technology (ETH) in Zurich developed the advanced catalytic converter process strategy. Commercial products based on the PSI know-how will be introduced to the market in the near future.

Beat Gerber | alfa
Further information:
http://www.psi.ch

More articles from Ecology, The Environment and Conservation:

nachricht When corals eat plastics
24.05.2018 | Justus-Liebig-Universität Gießen

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>