PHOTOCATALYTIC APPLICATIONS IN BELGIUM, PURIFYING THE AIR THROUGH THE PAVEMENT

摘要

The use of materials can influence to a large extend the environmental impact of traffic andof road infrastructure. Especially at urban areas, where the risk of smog formation duringhot summer days is high, the use of photocatalytic pavements can reduce the air pollutionsignificantly.A first application on the side roads of the main entrance axis in Antwerp has been studiedby the Belgian Road Research Centre [1]. Although measurements on site did not give theexpected results due to the configuration of the road surface, the laboratory resultsindicated a good efficiency towards NO and NO_2 abatement as well as a good durability ofthis air cleaning characteristic.New applications in industrial zones (in the framework of an INTERREG project) as well asin the tunnels of Brussels (LIFE+ project) are put in place in order to measure the influenceon site.The photocatalytic material, titanium dioxide, is introduced in the top layer of the concretepavement. In contact with light, TiO_2 is activated and able to reduce different pollutants inthe air. Special attention is given to the NO and NO_2 content in the air, since they are forover 50% caused by the exhaust of traffic and are at the base of smog, secondary ozoneand acid rain formation.This paper first describes the principle of photocatalytic materials through the results of theresearch project(s). Subsequently, the different applications in Antwerp (2005) and at theindustrial zone in Wijnegem (2011) will be described. In the latter, a double layeredconcrete is used. By using this configuration, the TiO2 can be added to the top layer, whilethe bottom layer is made of recycled concrete aggregates in order to reduce the ecologicalimpact.