How are volatile organic compounds (VOC) removed?
Distillers can remove VOCs by three methods: 1) gas vents, 2) fractional columns and 3) activated carbon filters (ACF). Distillers that use a combination of VOC removal methods are more efficient than one single method. Gas vents are small holes drilled into the passage leading to the cooling coils. Gas vents allow VOCs to escape the distiller before they enter the cooling section coils. These holes (one or two) are usually from .045 inches to .065 inches in diameter. Fractional column distillers (Figure 5) use differential cooling to remove VOCs. VOCs are removed when they condense in a different section of the fractional column than where water does. Fractional distillers usually cost more than distillers with gas vents or ACF cartridges. Figure 5. An illustration of a reflux distiller. Activated carbon filters (ACF) trap VOCs (refer to Activated Carbon Filtration in the Treatment Systems for Household Water Supplies Series). The ACF units are normally located at the end of the cooli
