VOC Generator

The CH Technologies VOC Generator is a counter current device used to generate volatile organic compound vapors from liquid and solid test articles. For a liquid test article, the sample is vaporized in a vertical column filled with glass beads to increase surface area for greater vaporization.

Liquid flows into the top of the column while warm air enters at the bottom of the column. A thermocouple, which measures the temperature of the air exiting the top of the column, feeds back to the air heater temperature controller to maintain a constant temperature of the exiting vapor. To prevent condensation of the vapor in the distribution tubing leading from the vaporizer column to the exposure chamber, dilution air is added immediately downstream from the top of the column. Excess liquid that is not evaporated is collected in a flask at the bottom of the vaporizer tube and eventually discarded.

To sublimate a solid test article, the glass beads in the vertical column are replaced with a course-granulated solid test article. Small mesh stainless steel screens are installed at the top and bottom of the column to prevent dispersion of granules into the air lines.

A stainless steel version of the VOC Generator is available for applications that require higher safety standards, e.g. generation of highly toxic or carcinogeneous vapors.