The 8.5 km west ring road A 26 in Linz, Upper Austria includes a fourth bridge on the Danube and two twin bored tunnels on each side of it, a 2.8 km north tunnel from the Danube to Heilham interchange and a 3.2 km south tunnel from the Danube to the railway station. The environmental impact study of the south section should be completed in end 2008 or early 2009 and construction is expected to start in July 2009. The north tunnel would be built from 2013. Read E-News Weekly 20/2006 & 30/2004. Click at/31.
The issue of the exhaust fumes and polluting particles in the tunnels has been delicate and has already met protests from local residents. Motor vehicles produce pollutant emissions from combustion engines, braking systems and tyres. The emissions have adverse effects on human health and the environment. Of the many thousands of tunnels around the world, only a small proportion estimated at less than 1% has vertical air dispersion (stacks) and only less that 0.01% (as estimated) has contaminant removal technologies to extract pollution from the ventilated tunnel air.
Once contaminants are generated a range of measures including portal dispersion, stacks and even pollution removal technology are available to manage the effect of tunnel contaminants upon the environment.
Upper Austria’s officials want the west ring road tunnels to be equipped with Aigner’s exhaust filters. A cleaning rate of 85% can technically be achieved and financially this is an extra cost of just EUR3 million out of a total investment of around EUR400 million for the southern tunnel. These filtering systems eliminate the need for exhaust towers. In Austria, ASFINAG is also considering to equip the Roppen tunnel on the Inn valley motorway with these filters. To know more about Aigner’s ECCO® filter systems, visit www.aigner.at and to know more about air cleaning technologies, click here.
In 2006, Aigner equipped the Le Vigne tunnel in Cesena, Italy with its air purification filters in partnership with Flakt Woods. Visit www.flaktwoods.it/ventilia/gal_stradali.pdf
The technology has also been installed in the M-30 tunnels in Madrid, where 29 air cleaning stations unique in Europe (14 supplied by Zitron) remove the pollutants from the air and avoid the emission of polluting and greenhouse gases to the atmosphere. In addition to supplying all the fans (an impressive 909 units totalling 60 MW), Zitron also installed half of the air purification systems. The M-30 tunnels are the first in Europe to be fitted with filters The tunnels are the first in Europe that include filters that eliminate carbon dioxide and nitrogen oxides, two of the main contaminants. Zitron installed 12 of the 25 carbon dioxide filters and all the four nitrogen oxide filters. To install these purification stations, Zitron teamed up with Aigner. Visit www.zitron.com 42/07.
