Personalized ventilation with embedded air treatment system for simultaneous cooling and sorption-based carbon and humidity capture

Abstract

This study presents a novel approach to address thermal comfort and air quality challenges in built environments using personalized ventilation (PV). Conventional techniques rely on delivering clean, cool and dehumidified outdoor air occupant microclimate. In contrast, this research extends the use of these conventional PV systems to deliver decarbonized and dehumidified air using a localized indoor air treatment system. The system meets air quality requirements of the occupant while minimizing its size and energy consumption through the innovative PV airflow supply from co-flow air terminal. Hence, a compact multi-functional personalized ventilation (MFPV) device, employing an adsorbent system for simultaneous CO2 and H2O capture from indoor air, is developed and its feasibility is tested. The device utilizes thermoelectric cooling (TEC) to cool the supply air and regenerate the adsorbent. Mathematical models are developed for the system to predict performance an appropriate control strategy. The models are verified experimentally using a constructed prototype of the device and used to optimize the design and operation via a four-way valve and switching the TEC current polarity such that the flow was periodically guided to cooling and regeneration TEC sides. The optimal operation was achieved with a purge-to-supply flowrate of 40 %, adsorbent mass of 125.3 g of Lewatit® VP OC 1065, along with two TEC modules with a power of 7.2.8 Wh and a cycle time of 7.5 min. The MFPV resulted in 22 % and 58 % energy savings compared to conventional co-flow and single flow PV system using treated outdoor air, respectively.