ISH 2021

•••6••• Innovationen Virus-free air New type of ventilator for effectice air purification With the advent of winter, life has moved back indoors – and, with it, the danger of catching the coronavirus in schools, offi- ces and shopping malls. A venti- lator that reduces the danger of infection could play a significant role in combating the corona- virus. In a project known as Co- Clean-up, the Fraunhofer Institu- te for Ceramic Technologies and Systems IKTS in Dresden and the Fraunhofer Institute for Toxico- logy and Experimental Medicine ITEM in Hannover have now de- veloped such a solution. This new system filters pathogens from ambient air and destroys them, leaving behind nothing but the nontoxic gas CO 2 . While there are already filter systems that clean ambient air, these merely capture the virus rather than destroy it. Failure to exchange the filter may result in a perforation in the used filter, which in turn can lead to a major discharge of the virus into the room. Swapping filters can also pose problems. How best to re- move the spent filter and then safely dispose of it along with its virus load? UV filters are one alter- native. These do destroy most of the virus, yet the process involved can often create other harmful sub-stances. In other words, they offer a partial solution at best. At first glance, there is little to distinguish the Fraunhofer venti- lator from existing sys-tems. The process behind it, however, is completely new. “Our ventilator system fully destroys viruses and any other organic material,” says Hans-Jürgen Friedrich, group ma- nager at Fraunhofer IKTS. “The only thing left are small quanti- ties of CO 2 and hydrogen. In other words, our process really does knock out the coronavirus.” The virus is oxidized to CO 2 In place of the filter found in con- ventional ventilators, the new system uses a process of cold combustion to remove the vi- rus. Ambient air is fed through a saline solution, which filters out the virus and any other organic particles. The cleaned air is then released back into the room. In the saline solution are two elec- trodes, across which a voltage is applied. At one electrode, the organic substances in the saline solution – including any viruses – are fully oxidized to form CO 2 , in a process also known as cold com- bustion; at the other, small quan- tities of hydrogen are produced. In a room of normal size contai- ning a fair number of people, this would only produce a couple of hundred milliliters of CO 2 and hy- drogen over the course of several hours. These two gases then dis- perse throughout the entire air within the room. By way of com- parison, each liter of air exhaled by a person – the equivalent of one breath – contains around 40 milliliters of CO 2 . At present, research teams are carrying out tests with unharm- ful substances. “For safety rea- sons, we don’t use the actual co- ronavirus for the tests,” explains Dr. Katharina Schwarz, head of department at Fraunhofer ITEM. “Instead, we use surrogates with very similar properties.” In tests at Fraunhofer IKTS, these surro- gates were added directly to the saline solution. Researchers then analyzed the decomposition of this biological material at the elec- trodes and measured how much of it remained in the cleaned air discharged by the system. This demonstrated that the various electrolytic processes – i.e., the key part of the system – function as required. In subsequent tests, the resear- chers will create an aerosol laden with the virus and pump this into the saline solution. Here, too, they will use less harmful surrogates. “To the best of my knowledge, there is no standardized procedu- re anywhere in Europe for using an airborne aerosol of a dange- rous virus in order to test the ef- fectiveness of air purification and air disinfection systems,” Schwarz says. Looking at aerosols more closely In another project funded by the Fraunhofer-Gesellschaft, Schwarz is working with healthy test sub- jects to investigate how the ae- rosol composition of exhaled air changes according to whether the person breathes normally or speaks, coughs and sings. Equip- ped with this knowledge, she plans to produce different types of aerosols, which will then be loaded with the virus and fed into the electrolytic cell. “But we have to be careful that the artificially produced aerosols don’t damage or decompose the test viruses,” she explains. “The key is to find a good balance.” The ventilator developed for Co- Clean-up will be unveiled as a de- monstrator at the con-clusion of the project in April 2021. It should then take another 18 months or so before the system is ready for market launch and compliant with regulatory requirements. Be- sides the coronavirus, the ventila- tor might then also be used to fil- ter other airborne contaminants such as livestock viruses or swine and avian flu. Fraunhofer IKTS is currently investigating further options for the elimination of air- borne pollutants. “But there are not many other ways of dealing with this kind of problem that just leave you with CO 2 at the end,” Friedrich explains. “Our method has big potential – and not only for the coronavirus!” Gel electrophoresis to detect electrochemical protein degradation. Foto: Fraunhofer IKTS Technologie- und Energie-Forum: Deutsche Heizungsindustrie ist Green Deal ready Unter der Überschrift „Green Deal ready“ organisiert der Bundesver- band der Deutschen Heizungsin- dustrie (BDH) mit der Messe Frankfurt das digitale Technolo- gie- und Energie-Forum. Die Schirmherrschaft übernimmt Staatssekretär Andreas Feicht (BMWi). Hauptpartner ist die Bran- cheninitiative Zukunft Gas, Gold- Partner das Institut für Institut für Wärme und Mobilität (IWO). Dane- ben bringen sich 12 weitere Part- nerverbände aktiv in das Forum ein. Im Fokus der Sondershow steht der Green Deal der EU. Ziel des Green Deals ist ein klimaneut- rales Europa bis zum Jahr 2050. Bis zum Jahr 2030 soll der CO2-Austoß gegenüber 1990 um 55% reduziert werden. Die Heizungsindustrie zeigt gemeinsam mit Ihren Part- nern Lösungsstrategien zur Errei- chung dieser ambitionierten Kli- maziele bezogen au f den Gebäudesektor auf. Thematisiert werden heiztechnische Lösungen wie hybride Systeme, Wärmepum- pen, Brennstoffzellenheizungen, Holzzentralheizungen, wasser- stofffähige Brennwerttechnik, bis hin zu digitalen Energiemanage- mentsystemen. Außerdem spielen die für den Wärmemarkt relevan- ten Energieträger Gas, Öl, Strom und Biomasse eine zentrale Rolle. Hier geht es um zunehmend grüne Energieträger wie Biomethan, Wasserstoff, Green Fuels, grünen Strom oder Holzenergie. Der Besucher des Forums findet alles Wissenswerte rund um die Wärmewende kompakt und zu- sammenhängend aufbereitet. Neben Filmbeiträgen und Live- Streams bietet das Technologie- und Energie-Forum umfangrei- ches Hintergrundmaterial der Heizungsindustrie und der betei- ligten Verbände. Continued from Page 1