Aimed at building a healthy living environment: An analysis of performance of Clean-Air Heat Pump system for ammonia removal

Clean-Air Heat Pump (CAHP) is an innovative system which combines a desiccant wheel with a heat pump which can improve indoor air quality during the process of hygro-thermal control without using additional energy. It is verified that organic gaseous pollutants in air can be effectively removed by the CAHP in our previous research papers but whether the air purification capability of the CAHP is equally effective for inorganic pollutants is unknown. Therefore, in this paper, the removal of ammonia (NH₃)-one typical inorganic pollutant by the CAHP was focused, and the effects of regeneration air temperature of the rotor and NH₃ concentration on NH₃ removal were elaborated analyzed. The results showed that NH₃ could not be continuously removed when the adsorbent-silica gel in the CAHP was regenerated by low-temperature thermal energy like 60 °C. A higher regeneration air temperature, possibly more than 90 °C, was required, in which case NH₃ removal and desorption efficiencies reached 86.5% and 93.8% when the NH₃ concentration was 2.5 ppm. Even if the NH₃ concentration in process air was increased to 7.1 ppm, the air cleaning efficiency was still maintained above 67%.