Mass Transfer Of Contaminants In Rotary Enthalpy Exchangers

Publisher Website
Google Scholar
Abstract
The present work is a study of reentrainment of a tracer gas formaldehyde via six rotary air‐to‐air heat exchangers (all enthalpy exchangers) in the northern part of Sweden. Five exchangers installed in office buildings and one in a day‐care centre were included in the study. Formaldehyde in indoor was used as a monitor pollutant and was determined in air samples collected in the ducts at four positions around the rotor of the exchanger, in the supply‐air duct and in the exhaust‐air duct. Air sampling of homogeneous duct air was performed simultaneously at the four positions using 2, 4‐dinitrophenylhydrazine‐impregnated glass fibre filters. The sample analysis of formaldehyde was made by high‐performance liquid chromatography. The reentrainment of formaldehyde was calculated and found to be 1‐9%. These results show that a rotary heat exchanger can be used in buildings where activities produce low levels of air pollutants, provided that the exchanger is properly installed and maintained.