While some developed countries take the clean water for granted, the lack of it has become a serious problem in many parts of the world. A new method to sterilize water using hot bubbles of carbon dioxide discovered by researchers in Australia may help the developing countries to get the access to clean water more easily.
This new method consists of a process that bubbles heated and unpressurized CO2?through wastewater?tank. As the bubbles travel through the water tank, they transfer heat to the water around them, while effectively destroying ant pathogens encountered.
To evaluate the treatment approach, researchers heated gas to different temperatures and bubbled it up through a sodium chloride solution that had been laced with E. coli bacteria and MS2 viruses. The sterilization capacity of CO2?was compared with that of air at temperatures of 7° C to 205° C. Both CO2?and air proved more effective at higher heat regimes. However, CO2?consistently destroyed bacteria and viruses at a quicker pace and was most efficient at temperatures of 100° C to 205° C
The team says the method has several advantages over existing water purification technologies. Since it takes less energy to heat a gas than it does to boil a liquid, the method is more energy efficient. It is also less potentially harmful than chemical methods such as adding chlorine, and simpler than using ultraviolet radiation. It also provides scope for reusing waste gases captured from power pants, landfills and other facilities.