We addressed "Purify The Air" initially by studying the resources provided by NASA and ESA, which gave us an overlook in subjects such as air pollution changes, air revitalization in ISS, pollutants dissociation reactions, life support systems in ISS, oxygen production alternatives (such as the Sabatier equation and water hydrolysis) and biological air filters.
We decided to stick to indoor environments in the earth such as houses, in which the biggest problem in maintaining the air quality normalized is controlling the CO2 and O2 concentrations, that we tackled by choosing to use colonies of lichens that are capable of making photosynthesis, which will actively receive light and continue working to normalize O2.
To solve the challenge of filtering the air from particles and eliminating viruses and bacteria we chose to use a dry heat sterilizer and HEPA graded filters.
First process:
The air is pulled from the indoors environment into the BOGAS by a fan which leads it to a HEPA graded micrometer filter and goes to the sterilizing chamber
Second process:
When entering the sterilizing chamber, the air will encounter a porous insulator with mass with Nichrome resistors wires through (chosen due to its high melting point), which will heat the air and kill the pathogens which reside in it. Subsequently, the air, now sterilized, goes to the lichens colonies, where during its way is cooled down.
Third process
Reaching the next chamber, the air encounters various colonies of lichens (which are in a modular and replaceable system), where the lichens being actively illuminated uses the carbon dioxide and produce oxygen, in photosynthesis. Thereafter, the air is pulled from the chamber through another HEPA micrometer filter and is released into the environment again, now pure and oxygenized.
We chose "Purify The Air" due to its broad capacity for innovation and room for ideas. Researching about pollution and air quality standards led us to various concepts on how to address the dissociation of pollutants and produce oxygen. However, after analyzing how the distribution of SO2 and NO2 lessened recently, as shown in satellite data provided by NASA, we concluded that we should stick to simpleness and focus on carbon dioxide reduction and oxygen production in an indoor environment. After searching through different methods of analyzing the air quality, such as a mass spectrometer (proved inviable due to its price and use), and chemical equations that produce oxygen, like the Sabatier equation and water electrolysis, we concluded that the most viable solution was using the photosynthesis reaction. After that, we had to think of something that would do the reaction determinating that plants are an inviable solution, the option of using algae appeared, but instead, we opted for lichens, which have a better adaptation and survivability in different environments, also having easy cultivation and can easily be replaced when needed. Then we tackled the challenge of preventing viruses and bacteria from staying in the air, in which we decided to use a dry heat sterilizer.
After seeing how the emition of nitrogen dioxide and sulfur dioxide were decreasing due to quarantine, we focused on carbon dioxide. We searched ways to eliminate it, like the sabatier reaction, but it was unviable and we viewed the slica gel NASA uses but decided to go with autotrophic species, like lichens.
We thought of ways of measuring the amount of carbon dioxide on the air, first we considered a mass spectometer, like the one used by ESA air revitalization system but it was too expensive, then we considered a carbon dioxide sensor, but they were either too expensive or interfered by other carbon fonts such as perfumes.
After that, we thought of how to eliminate microorganisms and decided on hot air sterilization.
We decided using lichens to eliminate carbon dioxide instead of just algae or other plants for their capacity of living in many environmental coinditions