Bio Tech Infrastructure / Clean Air

Increased European regulations limit the amount of particulate matter that is allowed in densely populated areas. This calls for innovations to keep our cities liveable and sustainable. A big challenge are highways and busy roads in the vicinity of city centres, specifically tunnel entries and exits. In these areas daily traffic causes a high concentration of NOx and CO2 gases, as well as particulate matter (PM2.5 and PM10). Depending on local weather conditions, this polluted air might easily reach the city. During the Bio Tech Infrastructure / Clean Air project, a natural, air-purifying technology was developed that can be integrated into the side of the road. It consists of panels of natural moss that filter the air and improve its quality. The polluted air is actively sucked in by fans installed in the panels and then blown through a layer of moss. The filtered air is then returned to the ambient atmosphere, minus the fine particles. In addition to the natural filtering of fine dust, the mosses also absorb sound. The modules are equipped with sensors that accurately measure the air quality. The need for irrigation and ventilation is automated and can be controlled from a distance via the internet. Furthermore a smart swivel system, suitable for one-side access, simplifies maintenance and prevents having to shut down the highway. To reach the most efficient positioning of the modules, several setups were tested and analysed, taking into consideration the air flow created by nature and traffic, and the subsequent concentration of polluted air. Currently a pilot project with 45 m² active surface is being tested along the future national road N434 (RijnlandRoute) in the Netherlands. Promising results have led to further development of the system for alternative contexts, like railroads.