MASS TRANSFER COEFFICIENT FOR HYDROGEN SULFIDE EMISSION FROM AQUEOUS SOLUTIONS AND LIQUID SWINE MANURE

Abstract

Mass transfer coefficient for hydrogen sulfide emission from an aqueous solution and liquid manure into theair was determined using a convective emission chamber where air temperature, velocity, turbulence, and relativehumidity were precisely controlled. The mass transfer coefficient was determined from experimental data and correlatedto liquid temperature, air temperature, and air velocity using a dimensional analysis method. Typical values of airtemperature (15-35C), air velocity (0.1-0.5 m/s), and liquid manure temperature (15-35C) found in under-floor manurestorage pits were used. The mass transfer coefficient increased as liquid temperature increased and decreased as the airvelocity and air temperature increased. When the liquid temperature was higher than the air temperature, the masstransfer coefficient increased as the difference between the two temperatures increased. This result implies that higheremission rate of H2S is likely to occur in a situation where the liquid temperature is higher than the air temperature.Sensitivity analysis showed that the mass transfer coefficient is more sensitive to changes in liquid and air temperaturethan to air velocity above the liquid.