Mann+Hummel has now installed more than 400 of its Filter Cubes worldwide, spread across 140 columns and cleaning almost two billion litres of air per hour – roughly equivalent to the air demand of of 4.1 million people.

“Many people think intensively about the one kilo of food and the three litres of liquid they consume every day, but we very rarely think about the quality of the approximately 12,000 litres of air that each of us breathes every day,” said Jan-Eric Raschke, director air solution systems for the company, which is headquartered in Ludwigsburg, Germany. “We all agree it would be best if our air was so clean that it didn’t need to be cleaned at all, but unfortunately it is not. Cities and metropolitan areas in particular face enormous challenges.”

Binding NO2

Mann+Hummel has developed the Filter Cube technology for particularly polluted roads and junctions. The Cubes draw in the polluted air and bind over 80% of the nitrogen dioxide (NO2) and particulate matter (PM10). The heart of the technology is a combination filter which comprises a highly effective nonwoven particle filtration layer and activated carbon layers that adsorb nitrogen dioxide. The activated carbon media absorb NO2 very effectively due to their large surface area. The technology is characterised by a particularly low pressure drop. As a result, it effectively cleans the air with very little use of energy. Thanks to their modular design, the Filter Cubes can be assembled to form adaptable filter columns.

We very rarely think about the quality of the approximately 12,000 litres of air that each of us breathes every day

In addition to various locations in Germany, Mann+Hummel Filter Cubes are now used in Brazil, China, India and South Korea and further projects are currently being planned in Hong Kong, Mexico, Colombia, Singapore, Taiwan and Thailand.

Effectiveness

The first systems were installed in December 2018 in Stuttgart, the capital of the German state of Baden-Württemberg. In 2020, a scientific report that examined the effectiveness of the installations along the street “Am Neckartor” concluded that, on average, a reduction of 9% in nitrogen dioxide pollution was achieved, and in the area of the sidewalk and close to the buildings even a decrease of ten to 19%. The studies focusing on particulate matter PM10 showed a reduction of more than 10% on average. Ozone concentrations were reduced by more than 11%.

Along Landshuter Allee in Munich, Germany, nine more columns with a total of 27 Cubes will ensure better air in Munich from this month.

Scientific support for the project in Munich is being provided by researchers from the Universities of Bayreuth and Augsburg, the East Bavarian Technical University of Regensburg and the Technical University of Munich.

“Based on the different expertise of the four project partners, we can get a very comprehensive picture of the real effect of the air filter systems along the road,” said Professor Anke Nölscher, who is coordinating the project at the University of Bayreuth. “We will take a close look at the filter material, test the use of the filters in the field, and measure air quality, air transport and traffic patterns in the process.”

www.mann-hummel.com