Absorbability of contaminants from room air by snow cooling system.

Snow has already been used effectively as a cold energy resource in some heavy snowfall areasin Japan. As the surface of snow is covered with cold melting water when snow is used as a coldenergy resource, we can expect gas absorption on the surface. By this mechanism of the gasabsorption, some airborne contaminants such as dust or harmful gases can be removed by themelting snow surface. In the snow cooling system, the air is cooled directly at the surface of avertical snow hole drilled through the snow block, some contaminants are removedautomatically and simultaneously with the heat transfer process. In this study, the authorsmeasured the absorbability of tobacco smoke, formaldehyde, ammonia gas and some indoor aircontaminants in a pilot plant of the snow cooling system. Experimental results showed that 40%formaldehyde and ammonia were removed when the inlet air temperature was cooled downfrom 30 degrees C to 13 degrees C. Also some contaminants included in tobacco smoke wereremoved by this system. This filter effect of the snow surface can be put to practical use incontamination control during air conditioning.