Smart air filter columns connected to the Industrial IoT reduce health risks from fine dust and nitrogen oxides. The smart Filter Cubes from MANN+HUMMEL succeed in reducing the pollutant load in the outside air. An optiMEAS IoT device controls on-demand, energy-saving operation and ensures connection to the cloud.
The challenge: Low air quality on busy roads
Fine dust, allergens, ozone, nitrogen oxides – the air in large cities is often heavily polluted. Especially at busy roads, intersections and traffic lights, the air is thick and the health of residents, passers-by and other road users is at risk. Around the world, major cities in particular are struggling with these problems and have found various solutions to them – ranging from driving bans to attempts to reduce the concentration of hazardous substances.
Stuttgart, the capital of the German state of Baden-Württemberg, has launched a pilot project together with the state’s Ministry of Transport and the Ludwigsburg-based filtration specialist MANN+HUMMEL. The aim is to develop a stationary filter solution for outdoor air that removes the particularly critical pollutants nitrogen dioxide and fine dust from the air with the lowest possible energy consumption.
The solution: High-performance filters networked with the Industrial IoT
Within two years, MANN+HUMMEL developed the triple-stackable air filter system “Filter Cube”, which effectively removes both fine dust and nitrogen dioxide from the air. The Filter Cube is a cube with a side length of one meter, inside which there is an innovative filter system. It removes more than 80 percent of nitrogen dioxide and fine dust from the air with a fine dust filter and an activated carbon layer with an extra large surface area.
The partner for the development of the gateways for the Industrial IoT is optiMEAS GmbH. Their smartMINI IoT edge device is installed in the base of the filter column and serves as a gateway and control unit. The integrated software provides IoT functions for data acquisition and transmission, enabling bidirectional communication between the Filter Cubes and MANN+HUMMEL’s cloud server.
smartMINI records the operating variables of up to three Cubes, including GPS position, speed, power consumption and temperature of the fans, error messages and operating hours. Added to this is the data from a rain sensor. Via MQTT, the IoT device sends the live data to the cloud. In the opposite direction, smartMINI receives the control commands from the cloud dashboard and passes them on to the fans via a Modbus interface.
The dashboard analyzes all data and determines how the system should behave based on thresholds and defaults. For example, the fan automatically turns off when it rains, because then the air purification is not necessary. And near residential areas, it switches to a lower speed at night to reduce noise emissions.
The stationary air purifiers are designed for 24/7/365 operation and is fail-safe thanks to integrated watchdogs. Software updates are performed as over-the-air updates during operation and can be easily triggered from the dashboard
The result: Purified air in critical places in the city
More than 100 columns now provide better air – in Stuttgart and Heilbronn as well as in South Korea, China, India and Brazil. Per hour, a filter column consisting of three cubes cleans 14,500 m³ of air. It has been shown that the column is effective within a radius of 15 to 20 meters and significantly reduces pollution levels there.
Demand-based remote control via smartMINI ensures efficient operation with low energy consumption and ensures that noise protection requirements are reliably met around the clock.
Tracked diagnostic data not only creates the data basis for further analyses, but also provides detailed information about the current “health condition” of the plant. Problems can thus be identified at an early stage and service calls can be easily planned.